diff --git a/src/card_table.h b/src/card_table.h
index a6284e3..9dc7201 100644
--- a/src/card_table.h
+++ b/src/card_table.h
@@ -76,8 +76,8 @@
   template <typename Visitor, typename FingerVisitor>
   void Scan(SpaceBitmap* bitmap, byte* scan_begin, byte* scan_end,
             const Visitor& visitor, const FingerVisitor& finger_visitor) const
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(bitmap->HasAddress(scan_begin));
     DCHECK(bitmap->HasAddress(scan_end - 1));  // scan_end is the byte after the last byte we scan.
     byte* card_cur = CardFromAddr(scan_begin);
diff --git a/src/check_jni.cc b/src/check_jni.cc
index 0e521af..c53a1e3 100644
--- a/src/check_jni.cc
+++ b/src/check_jni.cc
@@ -124,7 +124,7 @@
 };
 
 static bool ShouldTrace(JavaVMExt* vm, const Method* method)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // If both "-Xcheck:jni" and "-Xjnitrace:" are enabled, we print trace messages
   // when a native method that matches the -Xjnitrace argument calls a JNI function
   // such as NewByteArray.
@@ -151,7 +151,7 @@
  public:
   // For JNIEnv* functions.
   explicit ScopedCheck(JNIEnv* env, int flags, const char* functionName)
-      SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCK_FUNCTION(Locks::mutator_lock_)
       : soa_(env) {
     Init(flags, functionName, true);
     CheckThread(flags);
@@ -160,12 +160,12 @@
   // For JavaVM* functions.
   // TODO: it's not correct that this is a lock function, but making it so aids annotalysis.
   explicit ScopedCheck(JavaVM* vm, bool has_method, const char* functionName)
-      SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCK_FUNCTION(Locks::mutator_lock_)
       : soa_(vm) {
     Init(kFlag_Invocation, functionName, has_method);
   }
 
-  ~ScopedCheck() UNLOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {}
+  ~ScopedCheck() UNLOCK_FUNCTION(Locks::mutator_lock_) {}
 
   const ScopedObjectAccess& soa() {
     return soa_;
@@ -195,7 +195,7 @@
    * Works for both static and instance fields.
    */
   void CheckFieldType(jobject java_object, jfieldID fid, char prim, bool isStatic)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Field* f = CheckFieldID(fid);
     if (f == NULL) {
       return;
@@ -241,7 +241,7 @@
    * Assumes "jobj" has already been validated.
    */
   void CheckInstanceFieldID(jobject java_object, jfieldID fid)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Object* o = soa_.Decode<Object*>(java_object);
     if (o == NULL || !Runtime::Current()->GetHeap()->IsHeapAddress(o)) {
       JniAbortF(function_name_, "field operation on invalid %s: %p",
@@ -275,7 +275,7 @@
    * 'expectedType' will be "L" for all objects, including arrays.
    */
   void CheckSig(jmethodID mid, const char* expectedType, bool isStatic)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* m = CheckMethodID(mid);
     if (m == NULL) {
       return;
@@ -301,7 +301,7 @@
    * Assumes "java_class" has already been validated.
    */
   void CheckStaticFieldID(jclass java_class, jfieldID fid)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Class* c = soa_.Decode<Class*>(java_class);
     const Field* f = CheckFieldID(fid);
     if (f == NULL) {
@@ -323,7 +323,7 @@
    * Instances of "java_class" must be instances of the method's declaring class.
    */
   void CheckStaticMethod(jclass java_class, jmethodID mid)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const Method* m = CheckMethodID(mid);
     if (m == NULL) {
       return;
@@ -343,7 +343,7 @@
    * will be handled automatically by the instanceof check.)
    */
   void CheckVirtualMethod(jobject java_object, jmethodID mid)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const Method* m = CheckMethodID(mid);
     if (m == NULL) {
       return;
@@ -392,7 +392,7 @@
    * Use the kFlag_NullableUtf flag where 'u' field(s) are nullable.
    */
   void Check(bool entry, const char* fmt0, ...)
-      SHARED_LOCKS_REQUIRED (GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED (Locks::mutator_lock_) {
     va_list ap;
 
     const Method* traceMethod = NULL;
@@ -594,7 +594,7 @@
    * to "running" mode before doing the checks.
    */
   bool CheckInstance(InstanceKind kind, jobject java_object)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const char* what = NULL;
     switch (kind) {
     case kClass:
@@ -668,7 +668,7 @@
    *
    * Since we're dealing with objects, switch to "running" mode.
    */
-  void CheckArray(jarray java_array) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void CheckArray(jarray java_array) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (java_array == NULL) {
       JniAbortF(function_name_, "jarray was NULL");
       return;
@@ -689,7 +689,7 @@
     }
   }
 
-  Field* CheckFieldID(jfieldID fid) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  Field* CheckFieldID(jfieldID fid) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (fid == NULL) {
       JniAbortF(function_name_, "jfieldID was NULL");
       return NULL;
@@ -702,7 +702,7 @@
     return f;
   }
 
-  Method* CheckMethodID(jmethodID mid) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  Method* CheckMethodID(jmethodID mid) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (mid == NULL) {
       JniAbortF(function_name_, "jmethodID was NULL");
       return NULL;
@@ -722,7 +722,7 @@
    * Switches to "running" mode before performing checks.
    */
   void CheckObject(jobject java_object)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (java_object == NULL) {
       return;
     }
@@ -745,7 +745,7 @@
     }
   }
 
-  void CheckThread(int flags) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void CheckThread(int flags) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Thread* self = Thread::Current();
     if (self == NULL) {
       JniAbortF(function_name_, "a thread (tid %d) is making JNI calls without being attached", GetTid());
diff --git a/src/class_linker.cc b/src/class_linker.cc
index f6fb470..3c52370 100644
--- a/src/class_linker.cc
+++ b/src/class_linker.cc
@@ -60,7 +60,7 @@
 
 static void ThrowNoClassDefFoundError(const char* fmt, ...)
     __attribute__((__format__(__printf__, 1, 2)))
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 static void ThrowNoClassDefFoundError(const char* fmt, ...) {
   va_list args;
   va_start(args, fmt);
@@ -70,7 +70,7 @@
 
 static void ThrowClassFormatError(const char* fmt, ...)
     __attribute__((__format__(__printf__, 1, 2)))
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 static void ThrowClassFormatError(const char* fmt, ...) {
   va_list args;
   va_start(args, fmt);
@@ -80,7 +80,7 @@
 
 static void ThrowLinkageError(const char* fmt, ...)
     __attribute__((__format__(__printf__, 1, 2)))
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 static void ThrowLinkageError(const char* fmt, ...) {
   va_list args;
   va_start(args, fmt);
@@ -90,7 +90,7 @@
 
 static void ThrowNoSuchFieldError(const StringPiece& scope, Class* c, const StringPiece& type,
                                   const StringPiece& name)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ClassHelper kh(c);
   std::ostringstream msg;
   msg << "No " << scope << "field " << name << " of type " << type
@@ -104,7 +104,7 @@
 
 static void ThrowNullPointerException(const char* fmt, ...)
     __attribute__((__format__(__printf__, 1, 2)))
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 static void ThrowNullPointerException(const char* fmt, ...) {
   va_list args;
   va_start(args, fmt);
@@ -113,7 +113,7 @@
 }
 
 static void ThrowEarlierClassFailure(Class* c)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // The class failed to initialize on a previous attempt, so we want to throw
   // a NoClassDefFoundError (v2 2.17.5).  The exception to this rule is if we
   // failed in verification, in which case v2 5.4.1 says we need to re-throw
@@ -134,7 +134,7 @@
 }
 
 static void WrapExceptionInInitializer()
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Thread* self = Thread::Current();
   JNIEnv* env = self->GetJniEnv();
 
@@ -916,7 +916,7 @@
 
   // reinit clases_ table
   {
-    ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+    ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
     heap->FlushAllocStack();
     const Spaces& vec = heap->GetSpaces();
     // TODO: C++0x auto
@@ -985,7 +985,7 @@
   }
 
   {
-    MutexLock mu(*GlobalSynchronization::classlinker_classes_lock_);
+    MutexLock mu(*Locks::classlinker_classes_lock_);
     typedef Table::const_iterator It;  // TODO: C++0x auto
     for (It it = classes_.begin(), end = classes_.end(); it != end; ++it) {
       visitor(it->second, arg);
@@ -999,7 +999,7 @@
 }
 
 void ClassLinker::VisitClasses(ClassVisitor* visitor, void* arg) const {
-  MutexLock mu(*GlobalSynchronization::classlinker_classes_lock_);
+  MutexLock mu(*Locks::classlinker_classes_lock_);
   typedef Table::const_iterator It;  // TODO: C++0x auto
   for (It it = classes_.begin(), end = classes_.end(); it != end; ++it) {
     if (!visitor(it->second, arg)) {
@@ -1124,7 +1124,7 @@
 }
 
 static Class* EnsureResolved(Class* klass)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DCHECK(klass != NULL);
   // Wait for the class if it has not already been linked.
   Thread* self = Thread::Current();
@@ -1456,7 +1456,7 @@
 
 static void LinkCode(SirtRef<Method>& method, const OatFile::OatClass* oat_class,
                      uint32_t method_index)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Every kind of method should at least get an invoke stub from the oat_method.
   // non-abstract methods also get their code pointers.
   const OatFile::OatMethod oat_method = oat_class->GetOatMethod(method_index);
@@ -1891,7 +1891,7 @@
     LOG(INFO) << "Loaded class " << descriptor << source;
   }
   size_t hash = StringPieceHash()(descriptor);
-  MutexLock mu(*GlobalSynchronization::classlinker_classes_lock_);
+  MutexLock mu(*Locks::classlinker_classes_lock_);
   Table& classes = image_class ? image_classes_ : classes_;
   Class* existing = LookupClassLocked(descriptor.data(), klass->GetClassLoader(), hash, classes);
 #ifndef NDEBUG
@@ -1908,7 +1908,7 @@
 
 bool ClassLinker::RemoveClass(const char* descriptor, const ClassLoader* class_loader) {
   size_t hash = Hash(descriptor);
-  MutexLock mu(*GlobalSynchronization::classlinker_classes_lock_);
+  MutexLock mu(*Locks::classlinker_classes_lock_);
   typedef Table::iterator It;  // TODO: C++0x auto
   // TODO: determine if its better to search classes_ or image_classes_ first
   ClassHelper kh;
@@ -1933,7 +1933,7 @@
 
 Class* ClassLinker::LookupClass(const char* descriptor, const ClassLoader* class_loader) {
   size_t hash = Hash(descriptor);
-  MutexLock mu(*GlobalSynchronization::classlinker_classes_lock_);
+  MutexLock mu(*Locks::classlinker_classes_lock_);
   // TODO: determine if its better to search classes_ or image_classes_ first
   Class* klass = LookupClassLocked(descriptor, class_loader, hash, classes_);
   if (klass != NULL) {
@@ -1968,7 +1968,7 @@
 void ClassLinker::LookupClasses(const char* descriptor, std::vector<Class*>& classes) {
   classes.clear();
   size_t hash = Hash(descriptor);
-  MutexLock mu(*GlobalSynchronization::classlinker_classes_lock_);
+  MutexLock mu(*Locks::classlinker_classes_lock_);
   typedef Table::const_iterator It;  // TODO: C++0x auto
   // TODO: determine if its better to search classes_ or image_classes_ first
   ClassHelper kh(NULL, this);
@@ -1990,7 +1990,7 @@
 
 #if !defined(NDEBUG) && !defined(ART_USE_LLVM_COMPILER)
 static void CheckMethodsHaveGcMaps(Class* klass)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (!Runtime::Current()->IsStarted()) {
     return;
   }
@@ -2339,7 +2339,7 @@
 }
 
 static void CheckProxyConstructor(Method* constructor)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   CHECK(constructor->IsConstructor());
   MethodHelper mh(constructor);
   CHECK_STREQ(mh.GetName(), "<init>");
@@ -2378,7 +2378,7 @@
 }
 
 static void CheckProxyMethod(Method* method, SirtRef<Method>& prototype)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Basic sanity
   CHECK(!prototype->IsFinal());
   CHECK(method->IsFinal());
@@ -2526,7 +2526,7 @@
 }
 
 bool ClassLinker::WaitForInitializeClass(Class* klass, Thread* self, ObjectLock& lock)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   while (true) {
     self->AssertNoPendingException();
     lock.Wait();
@@ -3138,7 +3138,7 @@
 
 struct LinkFieldsComparator {
   explicit LinkFieldsComparator(FieldHelper* fh)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : fh_(fh) {}
   // No thread safety analysis as will be called from STL. Checked lock held in constructor.
   bool operator()(const Field* field1, const Field* field2) NO_THREAD_SAFETY_ANALYSIS {
@@ -3636,7 +3636,7 @@
   // lock held, because it might need to resolve a field's type, which would try to take the lock.
   std::vector<Class*> all_classes;
   {
-    MutexLock mu(*GlobalSynchronization::classlinker_classes_lock_);
+    MutexLock mu(*Locks::classlinker_classes_lock_);
     typedef Table::const_iterator It;  // TODO: C++0x auto
     for (It it = classes_.begin(), end = classes_.end(); it != end; ++it) {
       all_classes.push_back(it->second);
@@ -3652,18 +3652,18 @@
 }
 
 void ClassLinker::DumpForSigQuit(std::ostream& os) const {
-  MutexLock mu(*GlobalSynchronization::classlinker_classes_lock_);
+  MutexLock mu(*Locks::classlinker_classes_lock_);
   os << "Loaded classes: " << image_classes_.size() << " image classes; "
      << classes_.size() << " allocated classes\n";
 }
 
 size_t ClassLinker::NumLoadedClasses() const {
-  MutexLock mu(*GlobalSynchronization::classlinker_classes_lock_);
+  MutexLock mu(*Locks::classlinker_classes_lock_);
   return classes_.size() + image_classes_.size();
 }
 
 pid_t ClassLinker::GetClassesLockOwner() {
-  return GlobalSynchronization::classlinker_classes_lock_->GetExclusiveOwnerTid();
+  return Locks::classlinker_classes_lock_->GetExclusiveOwnerTid();
 }
 
 pid_t ClassLinker::GetDexLockOwner() {
diff --git a/src/class_linker.h b/src/class_linker.h
index eed9f6a..c21ff71 100644
--- a/src/class_linker.h
+++ b/src/class_linker.h
@@ -46,60 +46,60 @@
   // Creates the class linker by boot strapping from dex files.
   static ClassLinker* CreateFromCompiler(const std::vector<const DexFile*>& boot_class_path,
                                          InternTable* intern_table)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Creates the class linker from an image.
   static ClassLinker* CreateFromImage(InternTable* intern_table)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   ~ClassLinker();
 
   // Finds a class by its descriptor, loading it if necessary.
   // If class_loader is null, searches boot_class_path_.
   Class* FindClass(const char* descriptor, ClassLoader* class_loader)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Class* FindSystemClass(const char* descriptor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Define a new a class based on a ClassDef from a DexFile
   Class* DefineClass(const StringPiece& descriptor, ClassLoader* class_loader,
                      const DexFile& dex_file, const DexFile::ClassDef& dex_class_def)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Finds a class by its descriptor, returning NULL if it isn't wasn't loaded
   // by the given 'class_loader'.
   Class* LookupClass(const char* descriptor, const ClassLoader* class_loader)
-      LOCKS_EXCLUDED(GlobalSynchronization::classlinker_classes_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::classlinker_classes_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Finds all the classes with the given descriptor, regardless of ClassLoader.
   void LookupClasses(const char* descriptor, std::vector<Class*>& classes)
-      LOCKS_EXCLUDED(GlobalSynchronization::classlinker_classes_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::classlinker_classes_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  Class* FindPrimitiveClass(char type) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  Class* FindPrimitiveClass(char type) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // General class unloading is not supported, this is used to prune
   // unwanted classes during image writing.
   bool RemoveClass(const char* descriptor, const ClassLoader* class_loader)
-      LOCKS_EXCLUDED(GlobalSynchronization::classlinker_classes_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::classlinker_classes_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void DumpAllClasses(int flags) const
-      LOCKS_EXCLUDED(GlobalSynchronization::classlinker_classes_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::classlinker_classes_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void DumpForSigQuit(std::ostream& os) const
-      LOCKS_EXCLUDED(GlobalSynchronization::classlinker_classes_lock_);
+      LOCKS_EXCLUDED(Locks::classlinker_classes_lock_);
 
-  size_t NumLoadedClasses() const LOCKS_EXCLUDED(GlobalSynchronization::classlinker_classes_lock_);
+  size_t NumLoadedClasses() const LOCKS_EXCLUDED(Locks::classlinker_classes_lock_);
 
   // Resolve a String with the given index from the DexFile, storing the
   // result in the DexCache. The referrer is used to identify the
   // target DexCache and ClassLoader to use for resolution.
   String* ResolveString(uint32_t string_idx, const Method* referrer)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     String* resolved_string = referrer->GetDexCacheStrings()->Get(string_idx);
     if (UNLIKELY(resolved_string == NULL)) {
       Class* declaring_class = referrer->GetDeclaringClass();
@@ -113,13 +113,13 @@
   // Resolve a String with the given index from the DexFile, storing the
   // result in the DexCache.
   String* ResolveString(const DexFile& dex_file, uint32_t string_idx, DexCache* dex_cache)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Resolve a Type with the given index from the DexFile, storing the
   // result in the DexCache. The referrer is used to identity the
   // target DexCache and ClassLoader to use for resolution.
   Class* ResolveType(const DexFile& dex_file, uint16_t type_idx, const Class* referrer)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return ResolveType(dex_file,
                        type_idx,
                        referrer->GetDexCache(),
@@ -130,7 +130,7 @@
   // result in the DexCache. The referrer is used to identify the
   // target DexCache and ClassLoader to use for resolution.
   Class* ResolveType(uint16_t type_idx, const Method* referrer)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Class* resolved_type = referrer->GetDexCacheResolvedTypes()->Get(type_idx);
     if (UNLIKELY(resolved_type == NULL)) {
       Class* declaring_class = referrer->GetDeclaringClass();
@@ -143,7 +143,7 @@
   }
 
   Class* ResolveType(uint16_t type_idx, const Field* referrer)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Class* declaring_class = referrer->GetDeclaringClass();
     DexCache* dex_cache = declaring_class->GetDexCache();
     Class* resolved_type = dex_cache->GetResolvedType(type_idx);
@@ -163,7 +163,7 @@
                      uint16_t type_idx,
                      DexCache* dex_cache,
                      ClassLoader* class_loader)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Resolve a method with a given ID from the DexFile, storing the
   // result in DexCache. The ClassLinker and ClassLoader are used as
@@ -176,10 +176,10 @@
                         ClassLoader* class_loader,
                         const Method* referrer,
                         InvokeType type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* ResolveMethod(uint32_t method_idx, const Method* referrer, InvokeType type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* resolved_method = referrer->GetDexCacheResolvedMethods()->Get(method_idx);
     if (UNLIKELY(resolved_method == NULL || resolved_method->IsRuntimeMethod())) {
       Class* declaring_class = referrer->GetDeclaringClass();
@@ -192,7 +192,7 @@
   }
 
   Field* ResolveField(uint32_t field_idx, const Method* referrer, bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Field* resolved_field =
         referrer->GetDeclaringClass()->GetDexCache()->GetResolvedField(field_idx);
     if (UNLIKELY(resolved_field == NULL)) {
@@ -215,7 +215,7 @@
                       DexCache* dex_cache,
                       ClassLoader* class_loader,
                       bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Resolve a field with a given ID from the DexFile, storing the
   // result in DexCache. The ClassLinker and ClassLoader are used as
@@ -225,28 +225,28 @@
                          uint32_t field_idx,
                          DexCache* dex_cache,
                          ClassLoader* class_loader)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Get shorty from method index without resolution. Used to do handlerization.
   const char* MethodShorty(uint32_t method_idx, Method* referrer, uint32_t* length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Returns true on success, false if there's an exception pending.
   // can_run_clinit=false allows the compiler to attempt to init a class,
   // given the restriction that no <clinit> execution is possible.
   bool EnsureInitialized(Class* c, bool can_run_clinit, bool can_init_fields)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Initializes classes that have instances in the image but that have
   // <clinit> methods so they could not be initialized by the compiler.
-  void RunRootClinits() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void RunRootClinits() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void RegisterDexFile(const DexFile& dex_file)
       LOCKS_EXCLUDED(dex_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void RegisterDexFile(const DexFile& dex_file, SirtRef<DexCache>& dex_cache)
       LOCKS_EXCLUDED(dex_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void RegisterOatFile(const OatFile& oat_file)
       LOCKS_EXCLUDED(dex_lock_);
@@ -256,26 +256,26 @@
   }
 
   void VisitClasses(ClassVisitor* visitor, void* arg) const
-      LOCKS_EXCLUDED(GlobalSynchronization::classlinker_classes_lock_);
+      LOCKS_EXCLUDED(Locks::classlinker_classes_lock_);
   // Less efficient variant of VisitClasses that doesn't hold the classlinker_classes_lock_
   // when calling the visitor.
   void VisitClassesWithoutClassesLock(ClassVisitor* visitor, void* arg) const
-      LOCKS_EXCLUDED(GlobalSynchronization::classlinker_classes_lock_);
+      LOCKS_EXCLUDED(Locks::classlinker_classes_lock_);
 
   void VisitRoots(Heap::RootVisitor* visitor, void* arg) const
-      LOCKS_EXCLUDED(GlobalSynchronization::classlinker_classes_lock_, dex_lock_);
+      LOCKS_EXCLUDED(Locks::classlinker_classes_lock_, dex_lock_);
 
   const DexFile& FindDexFile(const DexCache* dex_cache) const
       LOCKS_EXCLUDED(dex_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   DexCache* FindDexCache(const DexFile& dex_file) const
       LOCKS_EXCLUDED(dex_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   bool IsDexFileRegistered(const DexFile& dex_file) const
       LOCKS_EXCLUDED(dex_lock_);
   void FixupDexCaches(Method* resolution_method) const
       LOCKS_EXCLUDED(dex_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Generate an oat file from a dex file
   bool GenerateOatFile(const std::string& dex_filename,
@@ -302,51 +302,51 @@
   // does not match the OatFile.
   const DexFile* FindDexFileInOatFileFromDexLocation(const std::string& location)
       LOCKS_EXCLUDED(dex_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 
   // Returns true if oat file contains the dex file with the given location and checksum
   static bool VerifyOatFileChecksums(const OatFile* oat_file,
                                      const std::string& dex_location,
                                      uint32_t dex_location_checksum)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // TODO: replace this with multiple methods that allocate the correct managed type.
   template <class T>
   ObjectArray<T>* AllocObjectArray(size_t length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return ObjectArray<T>::Alloc(GetClassRoot(kObjectArrayClass), length);
   }
 
   ObjectArray<Class>* AllocClassArray(size_t length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return ObjectArray<Class>::Alloc(GetClassRoot(kClassArrayClass), length);
   }
 
   ObjectArray<StackTraceElement>* AllocStackTraceElementArray(size_t length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void VerifyClass(Class* klass) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void VerifyClass(Class* klass) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   bool VerifyClassUsingOatFile(const DexFile& dex_file, Class* klass,
                                Class::Status& oat_file_class_status)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void ResolveClassExceptionHandlerTypes(const DexFile& dex_file, Class* klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void ResolveMethodExceptionHandlerTypes(const DexFile& dex_file, Method* klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Class* CreateProxyClass(String* name, ObjectArray<Class>* interfaces, ClassLoader* loader,
                           ObjectArray<Method>* methods, ObjectArray<ObjectArray<Class> >* throws)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   std::string GetDescriptorForProxy(const Class* proxy_class)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   Method* FindMethodForProxy(const Class* proxy_class, const Method* proxy_method)
       LOCKS_EXCLUDED(dex_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Get the oat code for a method when its class isn't yet initialized
   const void* GetOatCodeFor(const Method* method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Relocate the OatFiles (ELF images)
   void RelocateExecutable() LOCKS_EXCLUDED(dex_lock_);
@@ -358,59 +358,59 @@
   explicit ClassLinker(InternTable*);
 
   const OatFile::OatMethod GetOatMethodFor(const Method* method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Initialize class linker by bootstraping from dex files
   void InitFromCompiler(const std::vector<const DexFile*>& boot_class_path)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Initialize class linker from one or more images.
-  void InitFromImage() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void InitFromImage() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   OatFile* OpenOat(const ImageSpace* space)
       LOCKS_EXCLUDED(dex_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void InitFromImageCallback(Object* obj, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void FinishInit() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void FinishInit() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // For early bootstrapping by Init
   Class* AllocClass(Class* java_lang_Class, size_t class_size)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Alloc* convenience functions to avoid needing to pass in Class*
   // values that are known to the ClassLinker such as
   // kObjectArrayClass and kJavaLangString etc.
-  Class* AllocClass(size_t class_size) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  Class* AllocClass(size_t class_size) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   DexCache* AllocDexCache(const DexFile& dex_file)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
-  Field* AllocField() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
-  Method* AllocMethod() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+  Field* AllocField() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+  Method* AllocMethod() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   InterfaceEntry* AllocInterfaceEntry(Class* interface)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Class* CreatePrimitiveClass(const char* descriptor, Primitive::Type type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return InitializePrimitiveClass(AllocClass(sizeof(Class)), descriptor, type);
   }
   Class* InitializePrimitiveClass(Class* primitive_class,
                                   const char* descriptor,
                                   Primitive::Type type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 
   Class* CreateArrayClass(const std::string& descriptor, ClassLoader* class_loader)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void AppendToBootClassPath(const DexFile& dex_file)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void AppendToBootClassPath(const DexFile& dex_file, SirtRef<DexCache>& dex_cache)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void ConstructFieldMap(const DexFile& dex_file, const DexFile::ClassDef& dex_class_def,
                          Class* c, SafeMap<uint32_t, Field*>& field_map)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   size_t SizeOfClass(const DexFile& dex_file,
                      const DexFile::ClassDef& dex_class_def);
@@ -419,17 +419,17 @@
                  const DexFile::ClassDef& dex_class_def,
                  SirtRef<Class>& klass,
                  ClassLoader* class_loader)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void LoadField(const DexFile& dex_file, const ClassDataItemIterator& it, SirtRef<Class>& klass,
                  SirtRef<Field>& dst);
 
   void LoadMethod(const DexFile& dex_file, const ClassDataItemIterator& dex_method,
                   SirtRef<Class>& klass, SirtRef<Method>& dst)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void FixupStaticTrampolines(Class* klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Finds the associated oat class for a dex_file and descriptor
   const OatFile::OatClass* GetOatClass(const DexFile& dex_file, const char* descriptor);
@@ -438,70 +438,70 @@
   // the class was inserted, otherwise returns an existing class with
   // the same descriptor and ClassLoader.
   Class* InsertClass(const StringPiece& descriptor, Class* klass, bool image_class)
-      LOCKS_EXCLUDED(GlobalSynchronization::classlinker_classes_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::classlinker_classes_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void RegisterDexFileLocked(const DexFile& dex_file, SirtRef<DexCache>& dex_cache)
       EXCLUSIVE_LOCKS_REQUIRED(dex_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   bool IsDexFileRegisteredLocked(const DexFile& dex_file) const EXCLUSIVE_LOCKS_REQUIRED(dex_lock_);
   void RegisterOatFileLocked(const OatFile& oat_file) EXCLUSIVE_LOCKS_REQUIRED(dex_lock_)
       EXCLUSIVE_LOCKS_REQUIRED(dex_lock_);
 
   bool InitializeClass(Class* klass, bool can_run_clinit, bool can_init_statics)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   bool WaitForInitializeClass(Class* klass, Thread* self, ObjectLock& lock);
   bool ValidateSuperClassDescriptors(const Class* klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   bool InitializeSuperClass(Class* klass, bool can_run_clinit, bool can_init_fields)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   // Initialize static fields, returns true if fields were initialized.
   bool InitializeStaticFields(Class* klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool IsSameDescriptorInDifferentClassContexts(const char* descriptor,
                                                 const Class* klass1,
                                                 const Class* klass2)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool IsSameMethodSignatureInDifferentClassContexts(const Method* descriptor,
                                                      const Class* klass1,
                                                      const Class* klass2)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool LinkClass(SirtRef<Class>& klass, ObjectArray<Class>* interfaces)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool LinkSuperClass(SirtRef<Class>& klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool LoadSuperAndInterfaces(SirtRef<Class>& klass, const DexFile& dex_file)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool LinkMethods(SirtRef<Class>& klass, ObjectArray<Class>* interfaces)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool LinkVirtualMethods(SirtRef<Class>& klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool LinkInterfaceMethods(SirtRef<Class>& klass, ObjectArray<Class>* interfaces)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool LinkStaticFields(SirtRef<Class>& klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   bool LinkInstanceFields(SirtRef<Class>& klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   bool LinkFields(SirtRef<Class>& klass, bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 
   void CreateReferenceInstanceOffsets(SirtRef<Class>& klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void CreateReferenceStaticOffsets(SirtRef<Class>& klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void CreateReferenceOffsets(SirtRef<Class>& klass, bool is_static,
                               uint32_t reference_offsets)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // For use by ImageWriter to find DexCaches for its roots
   const std::vector<DexCache*>& GetDexCaches() {
@@ -518,12 +518,12 @@
                                                  const std::string& dex_location,
                                                  uint32_t dex_location_checksum)
       EXCLUSIVE_LOCKS_REQUIRED(dex_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* CreateProxyConstructor(SirtRef<Class>& klass, Class* proxy_class)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   Method* CreateProxyMethod(SirtRef<Class>& klass, SirtRef<Method>& prototype)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   std::vector<const DexFile*> boot_class_path_;
 
@@ -537,13 +537,13 @@
   // Class* instances. Results should be compared for a matching
   // Class::descriptor_ and Class::class_loader_.
   typedef std::multimap<size_t, Class*> Table;
-  Table image_classes_  GUARDED_BY(GlobalSynchronization::classlinker_classes_lock_);
-  Table classes_ GUARDED_BY(GlobalSynchronization::classlinker_classes_lock_);
+  Table image_classes_  GUARDED_BY(Locks::classlinker_classes_lock_);
+  Table classes_ GUARDED_BY(Locks::classlinker_classes_lock_);
 
   Class* LookupClassLocked(const char* descriptor, const ClassLoader* class_loader,
                            size_t hash, const Table& classes)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::classlinker_classes_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::classlinker_classes_lock_);
 
   // indexes into class_roots_.
   // needs to be kept in sync with class_roots_descriptors_.
@@ -585,7 +585,7 @@
   ObjectArray<Class>* class_roots_;
 
   Class* GetClassRoot(ClassRoot class_root)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(class_roots_ != NULL);
     Class* klass = class_roots_->Get(class_root);
     DCHECK(klass != NULL);
@@ -593,7 +593,7 @@
   }
 
   void SetClassRoot(ClassRoot class_root, Class* klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   ObjectArray<Class>* GetClassRoots() {
     DCHECK(class_roots_ != NULL);
diff --git a/src/class_linker_test.cc b/src/class_linker_test.cc
index 1eb5e0d..f249c6a 100644
--- a/src/class_linker_test.cc
+++ b/src/class_linker_test.cc
@@ -30,7 +30,7 @@
 class ClassLinkerTest : public CommonTest {
  protected:
   void AssertNonExistentClass(const std::string& descriptor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     EXPECT_TRUE(class_linker_->FindSystemClass(descriptor.c_str()) == NULL);
     Thread* self = Thread::Current();
     EXPECT_TRUE(self->IsExceptionPending());
@@ -41,12 +41,12 @@
   }
 
   void AssertPrimitiveClass(const std::string& descriptor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     AssertPrimitiveClass(descriptor, class_linker_->FindSystemClass(descriptor.c_str()));
   }
 
   void AssertPrimitiveClass(const std::string& descriptor, const Class* primitive)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ClassHelper primitive_ch(primitive);
     ASSERT_TRUE(primitive != NULL);
     ASSERT_TRUE(primitive->GetClass() != NULL);
@@ -83,7 +83,7 @@
   void AssertArrayClass(const std::string& array_descriptor,
                         const std::string& component_type,
                         ClassLoader* class_loader)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Class* array = class_linker_->FindClass(array_descriptor.c_str(), class_loader);
     ClassHelper array_component_ch(array->GetComponentType());
     EXPECT_STREQ(component_type.c_str(), array_component_ch.GetDescriptor());
@@ -92,7 +92,7 @@
   }
 
   void AssertArrayClass(const std::string& array_descriptor, Class* array)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ClassHelper kh(array);
     ASSERT_TRUE(array != NULL);
     ASSERT_TRUE(array->GetClass() != NULL);
@@ -135,7 +135,7 @@
     EXPECT_STREQ(kh.GetDescriptor(), "Ljava/io/Serializable;");
   }
 
-  void AssertMethod(Method* method) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void AssertMethod(Method* method) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     MethodHelper mh(method);
     EXPECT_TRUE(method != NULL);
     EXPECT_TRUE(method->GetClass() != NULL);
@@ -157,7 +157,7 @@
   }
 
   void AssertField(Class* klass, Field* field)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     FieldHelper fh(field);
     EXPECT_TRUE(field != NULL);
     EXPECT_TRUE(field->GetClass() != NULL);
@@ -167,7 +167,7 @@
   }
 
   void AssertClass(const std::string& descriptor, Class* klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ClassHelper kh(klass);
     EXPECT_STREQ(descriptor.c_str(), kh.GetDescriptor());
     if (descriptor == "Ljava/lang/Object;") {
@@ -291,7 +291,7 @@
   }
 
   void AssertDexFileClass(ClassLoader* class_loader, const std::string& descriptor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ASSERT_TRUE(descriptor != NULL);
     Class* klass = class_linker_->FindSystemClass(descriptor.c_str());
     ASSERT_TRUE(klass != NULL);
@@ -307,7 +307,7 @@
   }
 
   void AssertDexFile(const DexFile* dex, ClassLoader* class_loader)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ASSERT_TRUE(dex != NULL);
 
     // Verify all the classes defined in this file
@@ -350,7 +350,7 @@
   std::string class_descriptor;
   std::vector<CheckOffset> offsets;
 
-  bool Check() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool Check() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Class* klass = Runtime::Current()->GetClassLinker()->FindSystemClass(class_descriptor.c_str());
     CHECK(klass != NULL) << class_descriptor;
 
diff --git a/src/common_test.h b/src/common_test.h
index 4424d91..dee40e3 100644
--- a/src/common_test.h
+++ b/src/common_test.h
@@ -209,7 +209,7 @@
                                 );
   }
 
-  void MakeExecutable(Method* method) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void MakeExecutable(Method* method) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK(method != NULL);
 
     MethodHelper mh(method);
@@ -452,7 +452,7 @@
   }
 
   jobject LoadDex(const char* dex_name)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile* dex_file = OpenTestDexFile(dex_name);
     CHECK(dex_file != NULL);
     class_linker_->RegisterDexFile(*dex_file);
@@ -479,7 +479,7 @@
     }
   }
 
-  void CompileMethod(Method* method) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void CompileMethod(Method* method) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK(method != NULL);
     compiler_->CompileOne(method);
     MakeExecutable(method);
@@ -491,7 +491,7 @@
                            const char* class_name,
                            const char* method_name,
                            const char* signature)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     std::string class_descriptor(DotToDescriptor(class_name));
     Class* klass = class_linker_->FindClass(class_descriptor.c_str(), class_loader);
     CHECK(klass != NULL) << "Class not found " << class_name;
@@ -505,7 +505,7 @@
                             const char* class_name,
                             const char* method_name,
                             const char* signature)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     std::string class_descriptor(DotToDescriptor(class_name));
     Class* klass = class_linker_->FindClass(class_descriptor.c_str(), class_loader);
     CHECK(klass != NULL) << "Class not found " << class_name;
diff --git a/src/common_throws.cc b/src/common_throws.cc
index 5bd30b4..758e03b 100644
--- a/src/common_throws.cc
+++ b/src/common_throws.cc
@@ -27,7 +27,7 @@
 namespace art {
 
 static void AddReferrerLocation(std::ostream& os, const Method* referrer)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (referrer != NULL) {
     ClassHelper kh(referrer->GetDeclaringClass());
     std::string location(kh.GetLocation());
@@ -38,7 +38,7 @@
 }
 
 static void AddReferrerLocationFromClass(std::ostream& os, Class* referrer)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (referrer != NULL) {
     ClassHelper kh(referrer);
     std::string location(kh.GetLocation());
@@ -63,7 +63,7 @@
   DexCache* dex_cache = caller->GetDeclaringClass()->GetDexCache();
   const DexFile& dex_file = Runtime::Current()->GetClassLinker()->FindDexFile(dex_cache);
   std::ostringstream msg;
-  msg << "Attempt to invoke " << ToStr<InvokeType>(type).str() << " method '"
+  msg << "Attempt to invoke " << type << " method '"
       << PrettyMethod(method_idx, dex_file, true) << "' on a null object reference";
   Thread::Current()->ThrowNewException("Ljava/lang/NullPointerException;", msg.str().c_str());
 }
@@ -131,6 +131,8 @@
                                            "Attempt to get length of null array");
       break;
     default: {
+      // TODO: We should have covered all the cases where we expect a NPE above, this
+      //       message/logging is so we can improve any cases we've missed in the future.
       const DexFile& dex_file = Runtime::Current()->GetClassLinker()
           ->FindDexFile(throw_method->GetDeclaringClass()->GetDexCache());
       std::string message("Null pointer exception during instruction '");
@@ -146,7 +148,7 @@
 
 void ThrowIllegalAccessErrorClass(Class* referrer, Class* accessed) {
   std::ostringstream msg;
-  msg << "Illegal class access: '" << PrettyDescriptor(referrer) << "' -> '"
+  msg << "Illegal class access: '" << PrettyDescriptor(referrer) << "' attempting to access '"
       << PrettyDescriptor(accessed) << "'";
   AddReferrerLocationFromClass(msg, referrer);
   Thread::Current()->ThrowNewException("Ljava/lang/IllegalAccessError;", msg.str().c_str());
@@ -157,8 +159,8 @@
                                                    const Method* called,
                                                    InvokeType type) {
   std::ostringstream msg;
-  msg << "Illegal class access ('" << PrettyDescriptor(referrer) << "' -> '"
-      << PrettyDescriptor(accessed) << "') in attempt to invoke " << ToStr<InvokeType>(type).str()
+  msg << "Illegal class access ('" << PrettyDescriptor(referrer) << "' attempting to access '"
+      << PrettyDescriptor(accessed) << "') in attempt to invoke " << type
       << " method " << PrettyMethod(called).c_str();
   AddReferrerLocation(msg, caller);
   Thread::Current()->ThrowNewException("Ljava/lang/IllegalAccessError;", msg.str().c_str());
@@ -220,7 +222,8 @@
                                             const Method* referrer) {
   std::ostringstream msg;
   msg << "Expected '" << PrettyField(resolved_field) << "' to be a "
-      << (is_static ? "static" : "instance") << " field";
+      << (is_static ? "static" : "instance") << " field" << " rather than a "
+      << (is_static ? "instance" : "static") << " field";
   AddReferrerLocation(msg, referrer);
   Thread::Current()->ThrowNewException("Ljava/lang/IncompatibleClassChangeError;",
                                        msg.str().c_str());
diff --git a/src/common_throws.h b/src/common_throws.h
index 47186b0..ca2211f 100644
--- a/src/common_throws.h
+++ b/src/common_throws.h
@@ -25,56 +25,56 @@
 // NullPointerException
 
 void ThrowNullPointerExceptionForFieldAccess(Field* field, bool is_read)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 void ThrowNullPointerExceptionForMethodAccess(Method* caller, uint32_t method_idx, InvokeType type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 void ThrowNullPointerExceptionFromDexPC(Method* throw_method, uint32_t dex_pc)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 // IllegalAccessError
 
 void ThrowIllegalAccessErrorClass(Class* referrer, Class* accessed)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 void ThrowIllegalAccessErrorClassForMethodDispatch(Class* referrer, Class* accessed,
                                                    const Method* caller, const Method* called,
                                                    InvokeType type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 void ThrowIllegalAccessErrorMethod(Class* referrer, Method* accessed)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 void ThrowIllegalAccessErrorField(Class* referrer, Field* accessed)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 void ThrowIllegalAccessErrorFinalField(const Method* referrer, Field* accessed)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 // IncompatibleClassChangeError
 
 void ThrowIncompatibleClassChangeError(InvokeType expected_type, InvokeType found_type,
                                        Method* method, const Method* referrer)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 void ThrowIncompatibleClassChangeErrorClassForInterfaceDispatch(const Method* interface_method,
                                                                 Object* this_object,
                                                                 const Method* referrer)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 void ThrowIncompatibleClassChangeErrorField(const Field* resolved_field, bool is_static,
                                             const Method* referrer)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 // NoSuchMethodError
 
 void ThrowNoSuchMethodError(InvokeType type, Class* c, const StringPiece& name,
                             const StringPiece& signature, const Method* referrer)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 void ThrowNoSuchMethodError(uint32_t method_idx, const Method* referrer)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 }  // namespace art
 
diff --git a/src/compiler.cc b/src/compiler.cc
index b05e688..69de8ca 100644
--- a/src/compiler.cc
+++ b/src/compiler.cc
@@ -669,7 +669,7 @@
 
 static Class* ComputeCompilingMethodsClass(ScopedObjectAccess& soa,
                                            OatCompilationUnit* mUnit)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DexCache* dex_cache = mUnit->class_linker_->FindDexCache(*mUnit->dex_file_);
   ClassLoader* class_loader = soa.Decode<ClassLoader*>(mUnit->class_loader_);
   const DexFile::MethodId& referrer_method_id = mUnit->dex_file_->GetMethodId(mUnit->method_idx_);
@@ -680,7 +680,7 @@
 static Field* ComputeFieldReferencedFromCompilingMethod(ScopedObjectAccess& soa,
                                                         OatCompilationUnit* mUnit,
                                                         uint32_t field_idx)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DexCache* dex_cache = mUnit->class_linker_->FindDexCache(*mUnit->dex_file_);
   ClassLoader* class_loader = soa.Decode<ClassLoader*>(mUnit->class_loader_);
   return mUnit->class_linker_->ResolveField(*mUnit->dex_file_, field_idx, dex_cache,
@@ -691,7 +691,7 @@
                                                           OatCompilationUnit* mUnit,
                                                           uint32_t method_idx,
                                                           InvokeType type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DexCache* dex_cache = mUnit->class_linker_->FindDexCache(*mUnit->dex_file_);
   ClassLoader* class_loader = soa.Decode<ClassLoader*>(mUnit->class_loader_);
   return mUnit->class_linker_->ResolveMethod(*mUnit->dex_file_, method_idx, dex_cache,
@@ -1026,7 +1026,7 @@
   }
 
  private:
-  static void* Go(void* arg) LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+  static void* Go(void* arg) LOCKS_EXCLUDED(Locks::mutator_lock_) {
     WorkerThread* worker = reinterpret_cast<WorkerThread*>(arg);
     Runtime* runtime = Runtime::Current();
     if (worker->spawn_) {
@@ -1039,11 +1039,11 @@
     return NULL;
   }
 
-  void Go() LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+  void Go() LOCKS_EXCLUDED(Locks::mutator_lock_) {
     Go(this);
   }
 
-  void Run() LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+  void Run() LOCKS_EXCLUDED(Locks::mutator_lock_) {
     Thread* self = Thread::Current();
     for (size_t i = begin_; i < end_; i += stripe_) {
       callback_(context_, i);
@@ -1066,7 +1066,7 @@
 
 static void ForAll(CompilationContext* context, size_t begin, size_t end, Callback callback,
                    size_t thread_count)
-    LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+    LOCKS_EXCLUDED(Locks::mutator_lock_) {
   Thread* self = Thread::Current();
   self->AssertNoPendingException();
   CHECK_GT(thread_count, 0U);
@@ -1080,7 +1080,7 @@
   // Ensure we're suspended while we're blocked waiting for the other threads to finish (worker
   // thread destructor's called below perform join).
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_NE(self->GetState(), kRunnable);
   }
   STLDeleteElements(&threads);
@@ -1096,7 +1096,7 @@
 static bool SkipClass(ClassLoader* class_loader,
                       const DexFile& dex_file,
                       const DexFile::ClassDef& class_def)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (class_loader == NULL) {
     return false;
   }
@@ -1113,7 +1113,7 @@
 }
 
 static void ResolveClassFieldsAndMethods(const CompilationContext* context, size_t class_def_index)
-    LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+    LOCKS_EXCLUDED(Locks::mutator_lock_) {
   ScopedObjectAccess soa(Thread::Current());
   ClassLoader* class_loader = soa.Decode<ClassLoader*>(context->GetClassLoader());
   const DexFile& dex_file = *context->GetDexFile();
@@ -1182,7 +1182,7 @@
 }
 
 static void ResolveType(const CompilationContext* context, size_t type_idx)
-    LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+    LOCKS_EXCLUDED(Locks::mutator_lock_) {
   // Class derived values are more complicated, they require the linker and loader.
   ScopedObjectAccess soa(Thread::Current());
   ClassLinker* class_linker = context->GetClassLinker();
@@ -1221,7 +1221,7 @@
 }
 
 static void VerifyClass(const CompilationContext* context, size_t class_def_index)
-    LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+    LOCKS_EXCLUDED(Locks::mutator_lock_) {
   ScopedObjectAccess soa(Thread::Current());
   const DexFile::ClassDef& class_def = context->GetDexFile()->GetClassDef(class_def_index);
   const char* descriptor = context->GetDexFile()->GetClassDescriptor(class_def);
@@ -1474,7 +1474,7 @@
   // Ensure we're suspended while we're blocked waiting for the other threads to finish (worker
   // thread destructor's called below perform join).
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_NE(self->GetState(), kRunnable);
   }
   STLDeleteElements(&threads);
diff --git a/src/compiler.h b/src/compiler.h
index 4a7fc2a..c27bf95 100644
--- a/src/compiler.h
+++ b/src/compiler.h
@@ -53,11 +53,11 @@
   ~Compiler();
 
   void CompileAll(jobject class_loader, const std::vector<const DexFile*>& dex_files)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   // Compile a single Method
   void CompileOne(const Method* method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool IsDebuggingSupported() {
     return support_debugging_;
@@ -73,16 +73,16 @@
 
   // Stub to throw AbstractMethodError
   static ByteArray* CreateAbstractMethodErrorStub(InstructionSet instruction_set)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 
   // Generate the trampoline that's invoked by unresolved direct methods
   static ByteArray* CreateResolutionStub(InstructionSet instruction_set,
                                          Runtime::TrampolineType type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static ByteArray* CreateJniDlsymLookupStub(InstructionSet instruction_set)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // A class is uniquely located by its DexFile and the class_defs_ table index into that DexFile
   typedef std::pair<const DexFile*, uint32_t> ClassReference;
@@ -107,38 +107,38 @@
   // Callbacks from compiler to see what runtime checks must be generated.
 
   bool CanAssumeTypeIsPresentInDexCache(const DexFile& dex_file, uint32_t type_idx)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   bool CanAssumeStringIsPresentInDexCache(const DexFile& dex_file, uint32_t string_idx)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   // Are runtime access checks necessary in the compiled code?
   bool CanAccessTypeWithoutChecks(uint32_t referrer_idx, const DexFile& dex_file,
                                   uint32_t type_idx)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   // Are runtime access and instantiable checks necessary in the code?
   bool CanAccessInstantiableTypeWithoutChecks(uint32_t referrer_idx, const DexFile& dex_file,
                                               uint32_t type_idx)
-     LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+     LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   // Can we fast path instance field access? Computes field's offset and volatility.
   bool ComputeInstanceFieldInfo(uint32_t field_idx, OatCompilationUnit* mUnit,
                                 int& field_offset, bool& is_volatile, bool is_put)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   // Can we fastpath static field access? Computes field's offset, volatility and whether the
   // field is within the referrer (which can avoid checking class initialization).
   bool ComputeStaticFieldInfo(uint32_t field_idx, OatCompilationUnit* mUnit,
                               int& field_offset, int& ssb_index,
                               bool& is_referrers_class, bool& is_volatile, bool is_put)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   // Can we fastpath a interface, super class or virtual method call? Computes method's vtable
   // index.
   bool ComputeInvokeInfo(uint32_t method_idx, OatCompilationUnit* mUnit, InvokeType& type,
                          int& vtable_idx, uintptr_t& direct_code, uintptr_t& direct_method)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   // Record patch information for later fix up.
   void AddCodePatch(const DexFile* dex_file,
@@ -231,14 +231,14 @@
   // Compute constant code and method pointers when possible
   void GetCodeAndMethodForDirectCall(InvokeType type, InvokeType sharp_type, Method* method,
                                      uintptr_t& direct_code, uintptr_t& direct_method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Checks if class specified by type_idx is one of the image_classes_
   bool IsImageClass(const std::string& descriptor) const;
 
   void PreCompile(jobject class_loader, const std::vector<const DexFile*>& dex_files,
                   TimingLogger& timings)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
   void PostCompile(jobject class_loader, const std::vector<const DexFile*>& dex_files);
 
   // Attempt to resolve all type, methods, fields, and strings
@@ -246,37 +246,37 @@
   // ordering semantics.
   void Resolve(jobject class_loader, const std::vector<const DexFile*>& dex_files,
                TimingLogger& timings)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
   void ResolveDexFile(jobject class_loader, const DexFile& dex_file, TimingLogger& timings)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   void Verify(jobject class_loader, const std::vector<const DexFile*>& dex_files);
   void VerifyDexFile(jobject class_loader, const DexFile& dex_file)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   void InitializeClassesWithoutClinit(jobject class_loader,
                                       const std::vector<const DexFile*>& dex_files)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
   void InitializeClassesWithoutClinit(jobject class_loader, const DexFile& dex_file)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_, compiled_classes_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_, compiled_classes_lock_);
 
   void Compile(jobject class_loader, const std::vector<const DexFile*>& dex_files);
   void CompileDexFile(jobject class_loader, const DexFile& dex_file)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
   void CompileMethod(const DexFile::CodeItem* code_item, uint32_t access_flags,
                      InvokeType invoke_type, uint32_t method_idx,
                      jobject class_loader, const DexFile& dex_file)
       LOCKS_EXCLUDED(compiled_methods_lock_);
 
   static void CompileClass(const CompilationContext* context, size_t class_def_index)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   void SetGcMaps(jobject class_loader, const std::vector<const DexFile*>& dex_files)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
   void SetGcMapsDexFile(jobject class_loader, const DexFile& dex_file)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
   void SetGcMapsMethod(const DexFile& dex_file, Method* method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void InsertInvokeStub(const std::string& key, const CompiledInvokeStub* compiled_invoke_stub)
       LOCKS_EXCLUDED(compiled_invoke_stubs_lock_);
diff --git a/src/compiler_llvm/runtime_support_llvm.cc b/src/compiler_llvm/runtime_support_llvm.cc
index dd56ac8..4384e87 100644
--- a/src/compiler_llvm/runtime_support_llvm.cc
+++ b/src/compiler_llvm/runtime_support_llvm.cc
@@ -85,7 +85,7 @@
 }
 
 void art_test_suspend_from_code(Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   thread->FullSuspendCheck();
 }
 
@@ -115,21 +115,21 @@
 }
 
 void art_throw_div_zero_from_code()
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Thread* thread = art_get_current_thread_from_code();
   thread->ThrowNewException("Ljava/lang/ArithmeticException;",
                             "divide by zero");
 }
 
 void art_throw_array_bounds_from_code(int32_t index, int32_t length)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Thread* thread = art_get_current_thread_from_code();
   thread->ThrowNewExceptionF("Ljava/lang/ArrayIndexOutOfBoundsException;",
                              "length=%d; index=%d", length, index);
 }
 
 void art_throw_no_such_method_from_code(int32_t method_idx)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Thread* thread = art_get_current_thread_from_code();
   // We need the calling method as context for the method_idx
   Method* method = thread->GetCurrentMethod();
@@ -137,7 +137,7 @@
 }
 
 void art_throw_null_pointer_exception_from_code(uint32_t dex_pc)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Thread* thread = art_get_current_thread_from_code();
   NthCallerVisitor visitor(thread->GetManagedStack(), thread->GetTraceStack(), 0);
   visitor.WalkStack();
@@ -146,7 +146,7 @@
 }
 
 void art_throw_stack_overflow_from_code()
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Thread* thread = art_get_current_thread_from_code();
   if (Runtime::Current()->IsMethodTracingActive()) {
     TraceMethodUnwindFromCode(thread);
@@ -158,7 +158,7 @@
 }
 
 void art_throw_exception_from_code(Object* exception)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Thread* thread = art_get_current_thread_from_code();
   if (exception == NULL) {
     thread->ThrowNewException("Ljava/lang/NullPointerException;", "throw with null exception");
@@ -169,7 +169,7 @@
 
 int32_t art_find_catch_block_from_code(Method* current_method,
                                        uint32_t ti_offset)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Thread* thread = art_get_current_thread_from_code();
   Class* exception_type = thread->GetException()->GetClass();
   MethodHelper mh(current_method);
@@ -208,14 +208,14 @@
 Object* art_alloc_object_from_code(uint32_t type_idx,
                                    Method* referrer,
                                    Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return AllocObjectFromCode(type_idx, referrer, thread, false);
 }
 
 Object* art_alloc_object_from_code_with_access_check(uint32_t type_idx,
                                                      Method* referrer,
                                                      Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return AllocObjectFromCode(type_idx, referrer, thread, true);
 }
 
@@ -223,7 +223,7 @@
                                   Method* referrer,
                                   uint32_t length,
                                   Thread* /*thread*/)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return AllocArrayFromCode(type_idx, referrer, length, false);
 }
 
@@ -231,7 +231,7 @@
                                                     Method* referrer,
                                                     uint32_t length,
                                                     Thread* /*thread*/)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return AllocArrayFromCode(type_idx, referrer, length, true);
 }
 
@@ -239,7 +239,7 @@
                                             Method* referrer,
                                             uint32_t length,
                                             Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return CheckAndAllocArrayFromCode(type_idx, referrer, length, thread, false);
 }
 
@@ -247,13 +247,13 @@
                                                               Method* referrer,
                                                               uint32_t length,
                                                               Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return CheckAndAllocArrayFromCode(type_idx, referrer, length, thread, true);
 }
 
 static Method* FindMethodHelper(uint32_t method_idx, Object* this_object, Method* caller_method,
                                 bool access_check, InvokeType type, Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Method* method = FindMethodFast(method_idx, this_object, caller_method, access_check, type);
   if (UNLIKELY(method == NULL)) {
     method = FindMethodFromCode(method_idx, this_object, caller_method,
@@ -279,7 +279,7 @@
                                                            Object* this_object,
                                                            Method* referrer,
                                                            Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return FindMethodHelper(method_idx, this_object, referrer, true, kStatic, thread);
 }
 
@@ -287,7 +287,7 @@
                                                            Object* this_object,
                                                            Method* referrer,
                                                            Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return FindMethodHelper(method_idx, this_object, referrer, true, kDirect, thread);
 }
 
@@ -295,7 +295,7 @@
                                                             Object* this_object,
                                                             Method* referrer,
                                                             Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return FindMethodHelper(method_idx, this_object, referrer, true, kVirtual, thread);
 }
 
@@ -303,7 +303,7 @@
                                                           Object* this_object,
                                                           Method* referrer,
                                                           Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return FindMethodHelper(method_idx, this_object, referrer, true, kSuper, thread);
 }
 
@@ -312,7 +312,7 @@
                                                       Object* this_object,
                                                       Method* referrer,
                                                       Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return FindMethodHelper(method_idx, this_object, referrer, true, kInterface, thread);
 }
 
@@ -320,40 +320,40 @@
                                             Object* this_object,
                                             Method* referrer,
                                             Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return FindMethodHelper(method_idx, this_object, referrer, false, kInterface, thread);
 }
 
 Object* art_initialize_static_storage_from_code(uint32_t type_idx,
                                                 Method* referrer,
                                                 Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return ResolveVerifyAndClinit(type_idx, referrer, thread, true, false);
 }
 
 Object* art_initialize_type_from_code(uint32_t type_idx,
                                       Method* referrer,
                                       Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return ResolveVerifyAndClinit(type_idx, referrer, thread, false, false);
 }
 
 Object* art_initialize_type_and_verify_access_from_code(uint32_t type_idx,
                                                         Method* referrer,
                                                         Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Called when caller isn't guaranteed to have access to a type and the dex cache may be
   // unpopulated
   return ResolveVerifyAndClinit(type_idx, referrer, thread, false, true);
 }
 
 Object* art_resolve_string_from_code(Method* referrer, uint32_t string_idx)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return ResolveStringFromCode(referrer, string_idx);
 }
 
 int32_t art_set32_static_from_code(uint32_t field_idx, Method* referrer, int32_t new_value)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticPrimitiveWrite, sizeof(uint32_t));
   if (LIKELY(field != NULL)) {
     field->Set32(NULL, new_value);
@@ -369,7 +369,7 @@
 }
 
 int32_t art_set64_static_from_code(uint32_t field_idx, Method* referrer, int64_t new_value)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticPrimitiveWrite, sizeof(uint64_t));
   if (LIKELY(field != NULL)) {
     field->Set64(NULL, new_value);
@@ -385,7 +385,7 @@
 }
 
 int32_t art_set_obj_static_from_code(uint32_t field_idx, Method* referrer, Object* new_value)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticObjectWrite, sizeof(Object*));
   if (LIKELY(field != NULL)) {
     field->SetObj(NULL, new_value);
@@ -401,7 +401,7 @@
 }
 
 int32_t art_get32_static_from_code(uint32_t field_idx, Method* referrer)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticPrimitiveRead, sizeof(uint32_t));
   if (LIKELY(field != NULL)) {
     return field->Get32(NULL);
@@ -415,7 +415,7 @@
 }
 
 int64_t art_get64_static_from_code(uint32_t field_idx, Method* referrer)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticPrimitiveRead, sizeof(uint64_t));
   if (LIKELY(field != NULL)) {
     return field->Get64(NULL);
@@ -429,7 +429,7 @@
 }
 
 Object* art_get_obj_static_from_code(uint32_t field_idx, Method* referrer)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticObjectRead, sizeof(Object*));
   if (LIKELY(field != NULL)) {
     return field->GetObj(NULL);
@@ -444,7 +444,7 @@
 
 int32_t art_set32_instance_from_code(uint32_t field_idx, Method* referrer,
                                      Object* obj, uint32_t new_value)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstancePrimitiveWrite, sizeof(uint32_t));
   if (LIKELY(field != NULL)) {
     field->Set32(obj, new_value);
@@ -461,7 +461,7 @@
 
 int32_t art_set64_instance_from_code(uint32_t field_idx, Method* referrer,
                                      Object* obj, int64_t new_value)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstancePrimitiveWrite, sizeof(uint64_t));
   if (LIKELY(field != NULL)) {
     field->Set64(obj, new_value);
@@ -478,7 +478,7 @@
 
 int32_t art_set_obj_instance_from_code(uint32_t field_idx, Method* referrer,
                                        Object* obj, Object* new_value)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstanceObjectWrite, sizeof(Object*));
   if (LIKELY(field != NULL)) {
     field->SetObj(obj, new_value);
@@ -494,7 +494,7 @@
 }
 
 int32_t art_get32_instance_from_code(uint32_t field_idx, Method* referrer, Object* obj)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstancePrimitiveRead, sizeof(uint32_t));
   if (LIKELY(field != NULL)) {
     return field->Get32(obj);
@@ -508,7 +508,7 @@
 }
 
 int64_t art_get64_instance_from_code(uint32_t field_idx, Method* referrer, Object* obj)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstancePrimitiveRead, sizeof(uint64_t));
   if (LIKELY(field != NULL)) {
     return field->Get64(obj);
@@ -522,7 +522,7 @@
 }
 
 Object* art_get_obj_instance_from_code(uint32_t field_idx, Method* referrer, Object* obj)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstanceObjectRead, sizeof(Object*));
   if (LIKELY(field != NULL)) {
     return field->GetObj(obj);
@@ -537,7 +537,7 @@
 
 void art_fill_array_data_from_code(Method* method, uint32_t dex_pc,
                                    Array* array, uint32_t payload_offset)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Test: Is array equal to null? (Guard NullPointerException)
   if (UNLIKELY(array == NULL)) {
     art_throw_null_pointer_exception_from_code(dex_pc);
@@ -577,14 +577,14 @@
 //----------------------------------------------------------------------------
 
 int32_t art_is_assignable_from_code(const Class* dest_type, const Class* src_type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DCHECK(dest_type != NULL);
   DCHECK(src_type != NULL);
   return dest_type->IsAssignableFrom(src_type) ? 1 : 0;
 }
 
 void art_check_cast_from_code(const Class* dest_type, const Class* src_type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DCHECK(dest_type->IsClass()) << PrettyClass(dest_type);
   DCHECK(src_type->IsClass()) << PrettyClass(src_type);
   if (UNLIKELY(!dest_type->IsAssignableFrom(src_type))) {
@@ -597,7 +597,7 @@
 }
 
 void art_check_put_array_element_from_code(const Object* element, const Object* array)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (element == NULL) {
     return;
   }
@@ -631,7 +631,7 @@
 }
 
 uint32_t art_jni_method_start_synchronized(jobject to_lock, Thread* self)
-    UNLOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+    UNLOCK_FUNCTION(Locks::mutator_lock_) {
   self->DecodeJObject(to_lock)->MonitorEnter(self);
   return art_jni_method_start(self);
 }
@@ -643,7 +643,7 @@
 }
 
 void art_jni_method_end(uint32_t saved_local_ref_cookie, Thread* self)
-    SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCK_FUNCTION(Locks::mutator_lock_) {
   self->TransitionFromSuspendedToRunnable();
   PopLocalReferences(saved_local_ref_cookie, self);
 }
@@ -651,7 +651,7 @@
 
 void art_jni_method_end_synchronized(uint32_t saved_local_ref_cookie, jobject locked,
                                      Thread* self)
-    SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCK_FUNCTION(Locks::mutator_lock_) {
   self->TransitionFromSuspendedToRunnable();
   UnlockJniSynchronizedMethod(locked, self);  // Must decode before pop.
   PopLocalReferences(saved_local_ref_cookie, self);
@@ -659,7 +659,7 @@
 
 Object* art_jni_method_end_with_reference(jobject result, uint32_t saved_local_ref_cookie,
                                           Thread* self)
-    SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCK_FUNCTION(Locks::mutator_lock_) {
   self->TransitionFromSuspendedToRunnable();
   Object* o = self->DecodeJObject(result);  // Must decode before pop.
   PopLocalReferences(saved_local_ref_cookie, self);
@@ -676,7 +676,7 @@
 Object* art_jni_method_end_with_reference_synchronized(jobject result,
                                                        uint32_t saved_local_ref_cookie,
                                                        jobject locked, Thread* self)
-    SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCK_FUNCTION(Locks::mutator_lock_) {
   self->TransitionFromSuspendedToRunnable();
   UnlockJniSynchronizedMethod(locked, self);  // Must decode before pop.
   Object* o = self->DecodeJObject(result);
@@ -734,7 +734,7 @@
 // Handler for invocation on proxy methods. We create a boxed argument array. And we invoke
 // the invocation handler which is a field within the proxy object receiver.
 void art_proxy_invoke_handler_from_code(Method* proxy_method, ...)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   va_list ap;
   va_start(ap, proxy_method);
 
diff --git a/src/compiler_test.cc b/src/compiler_test.cc
index 0c53bb9..98b2142 100644
--- a/src/compiler_test.cc
+++ b/src/compiler_test.cc
@@ -31,14 +31,14 @@
 
 class CompilerTest : public CommonTest {
  protected:
-  void CompileAll(jobject class_loader) LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+  void CompileAll(jobject class_loader) LOCKS_EXCLUDED(Locks::mutator_lock_) {
     compiler_->CompileAll(class_loader, Runtime::Current()->GetCompileTimeClassPath(class_loader));
     MakeAllExecutable(class_loader);
   }
 
   void EnsureCompiled(jobject class_loader, const char* class_name, const char* method,
                       const char* signature, bool is_virtual)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+      LOCKS_EXCLUDED(Locks::mutator_lock_) {
     CompileAll(class_loader);
     Thread::Current()->TransitionFromSuspendedToRunnable();
     runtime_->Start();
diff --git a/src/debugger.cc b/src/debugger.cc
index b47377e..87ad446 100644
--- a/src/debugger.cc
+++ b/src/debugger.cc
@@ -98,7 +98,7 @@
   Method* method;
   uint32_t dex_pc;
 
-  int32_t LineNumber() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  int32_t LineNumber() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return MethodHelper(method).GetLineNumFromDexPC(dex_pc);
   }
 };
@@ -125,7 +125,7 @@
 };
 
 static std::ostream& operator<<(std::ostream& os, const Breakpoint& rhs)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   os << StringPrintf("Breakpoint[%s @%#x]", PrettyMethod(rhs.method).c_str(), rhs.dex_pc);
   return os;
 }
@@ -182,7 +182,7 @@
 static SingleStepControl gSingleStepControl GUARDED_BY(gBreakpointsLock);
 
 static bool IsBreakpoint(Method* m, uint32_t dex_pc)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   MutexLock mu(gBreakpointsLock);
   for (size_t i = 0; i < gBreakpoints.size(); ++i) {
     if (gBreakpoints[i].method == m && gBreakpoints[i].dex_pc == dex_pc) {
@@ -194,7 +194,7 @@
 }
 
 static Array* DecodeArray(JDWP::RefTypeId id, JDWP::JdwpError& status)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Object* o = gRegistry->Get<Object*>(id);
   if (o == NULL || o == kInvalidObject) {
     status = JDWP::ERR_INVALID_OBJECT;
@@ -209,7 +209,7 @@
 }
 
 static Class* DecodeClass(JDWP::RefTypeId id, JDWP::JdwpError& status)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Object* o = gRegistry->Get<Object*>(id);
   if (o == NULL || o == kInvalidObject) {
     status = JDWP::ERR_INVALID_OBJECT;
@@ -224,8 +224,8 @@
 }
 
 static Thread* DecodeThread(ScopedObjectAccessUnchecked& soa, JDWP::ObjectId threadId)
-    LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Object* thread_peer = gRegistry->Get<Object*>(threadId);
   if (thread_peer == NULL || thread_peer == kInvalidObject) {
     return NULL;
@@ -241,7 +241,7 @@
 }
 
 static JDWP::JdwpTag TagFromClass(Class* c)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   CHECK(c != NULL);
   if (c->IsArrayClass()) {
     return JDWP::JT_ARRAY;
@@ -272,7 +272,7 @@
  * Null objects are tagged JT_OBJECT.
  */
 static JDWP::JdwpTag TagFromObject(const Object* o)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return (o == NULL) ? JDWP::JT_OBJECT : TagFromClass(o->GetClass());
 }
 
@@ -491,7 +491,7 @@
 }
 
 static void SetDebuggerUpdatesEnabled(bool enabled) {
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Runtime::Current()->GetThreadList()->ForEach(SetDebuggerUpdatesEnabledCallback, &enabled);
 }
 
@@ -830,7 +830,7 @@
 
 JDWP::JdwpError Dbg::SetArrayElements(JDWP::ObjectId arrayId, int offset, int count,
                                       const uint8_t* src)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   JDWP::JdwpError status;
   Array* a = DecodeArray(arrayId, status);
   if (a == NULL) {
@@ -920,7 +920,7 @@
 }
 
 static JDWP::FieldId ToFieldId(const Field* f)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
 #ifdef MOVING_GARBAGE_COLLECTOR
   UNIMPLEMENTED(FATAL);
 #else
@@ -929,7 +929,7 @@
 }
 
 static JDWP::MethodId ToMethodId(const Method* m)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
 #ifdef MOVING_GARBAGE_COLLECTOR
   UNIMPLEMENTED(FATAL);
 #else
@@ -938,7 +938,7 @@
 }
 
 static Field* FromFieldId(JDWP::FieldId fid)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
 #ifdef MOVING_GARBAGE_COLLECTOR
   UNIMPLEMENTED(FATAL);
 #else
@@ -947,7 +947,7 @@
 }
 
 static Method* FromMethodId(JDWP::MethodId mid)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
 #ifdef MOVING_GARBAGE_COLLECTOR
   UNIMPLEMENTED(FATAL);
 #else
@@ -956,7 +956,7 @@
 }
 
 static void SetLocation(JDWP::JdwpLocation& location, Method* m, uint32_t dex_pc)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (m == NULL) {
     memset(&location, 0, sizeof(location));
   } else {
@@ -969,7 +969,7 @@
 }
 
 std::string Dbg::GetMethodName(JDWP::RefTypeId, JDWP::MethodId methodId)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Method* m = FromMethodId(methodId);
   return MethodHelper(m).GetName();
 }
@@ -1013,7 +1013,7 @@
 }
 
 static uint16_t DemangleSlot(uint16_t slot, Method* m)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (slot == kEclipseWorkaroundSlot) {
     return 0;
   } else if (slot == 0) {
@@ -1096,7 +1096,7 @@
 }
 
 void Dbg::OutputLineTable(JDWP::RefTypeId, JDWP::MethodId methodId, JDWP::ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   struct DebugCallbackContext {
     int numItems;
     JDWP::ExpandBuf* pReply;
@@ -1198,7 +1198,7 @@
 static JDWP::JdwpError GetFieldValueImpl(JDWP::RefTypeId refTypeId, JDWP::ObjectId objectId,
                                          JDWP::FieldId fieldId, JDWP::ExpandBuf* pReply,
                                          bool is_static)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   JDWP::JdwpError status;
   Class* c = DecodeClass(refTypeId, status);
   if (refTypeId != 0 && c == NULL) {
@@ -1268,7 +1268,7 @@
 
 static JDWP::JdwpError SetFieldValueImpl(JDWP::ObjectId objectId, JDWP::FieldId fieldId,
                                          uint64_t value, int width, bool is_static)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Object* o = gRegistry->Get<Object*>(objectId);
   if ((!is_static && o == NULL) || o == kInvalidObject) {
     return JDWP::ERR_INVALID_OBJECT;
@@ -1330,7 +1330,7 @@
 }
 
 bool Dbg::GetThreadName(JDWP::ObjectId threadId, std::string& name) {
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   ScopedObjectAccessUnchecked soa(Thread::Current());
   Thread* thread = DecodeThread(soa, threadId);
   if (thread == NULL) {
@@ -1348,7 +1348,7 @@
   }
 
   // Okay, so it's an object, but is it actually a thread?
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   if (DecodeThread(soa, threadId) == NULL) {
     return JDWP::ERR_INVALID_THREAD;
   }
@@ -1407,13 +1407,13 @@
 bool Dbg::GetThreadStatus(JDWP::ObjectId threadId, JDWP::JdwpThreadStatus* pThreadStatus, JDWP::JdwpSuspendStatus* pSuspendStatus) {
   ScopedObjectAccess soa(Thread::Current());
 
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Thread* thread = DecodeThread(soa, threadId);
   if (thread == NULL) {
     return false;
   }
 
-  MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+  MutexLock mu2(*Locks::thread_suspend_count_lock_);
 
   // TODO: if we're in Thread.sleep(long), we should return TS_SLEEPING,
   // even if it's implemented using Object.wait(long).
@@ -1447,28 +1447,28 @@
 JDWP::JdwpError Dbg::GetThreadDebugSuspendCount(JDWP::ObjectId threadId, JDWP::ExpandBuf* pReply) {
   ScopedObjectAccess soa(Thread::Current());
 
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Thread* thread = DecodeThread(soa, threadId);
   if (thread == NULL) {
     return JDWP::ERR_INVALID_THREAD;
   }
-  MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+  MutexLock mu2(*Locks::thread_suspend_count_lock_);
   expandBufAdd4BE(pReply, thread->GetDebugSuspendCount());
   return JDWP::ERR_NONE;
 }
 
 bool Dbg::ThreadExists(JDWP::ObjectId threadId) {
   ScopedObjectAccess soa(Thread::Current());
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   return DecodeThread(soa, threadId) != NULL;
 }
 
 bool Dbg::IsSuspended(JDWP::ObjectId threadId) {
   ScopedObjectAccess soa(Thread::Current());
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Thread* thread = DecodeThread(soa, threadId);
   CHECK(thread != NULL);
-  MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+  MutexLock mu2(*Locks::thread_suspend_count_lock_);
   return thread->IsSuspended();
 }
 
@@ -1477,7 +1477,7 @@
    public:
     ThreadListVisitor(const ScopedObjectAccessUnchecked& ts, Object* thread_group,
                       std::vector<JDWP::ObjectId>& thread_ids)
-        SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
         : ts_(ts), thread_group_(thread_group), thread_ids_(thread_ids) {}
 
     static void Visit(Thread* t, void* arg) {
@@ -1506,7 +1506,7 @@
   ScopedObjectAccessUnchecked soa(Thread::Current());
   Object* thread_group = gRegistry->Get<Object*>(thread_group_id);
   ThreadListVisitor tlv(soa, thread_group, thread_ids);
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Runtime::Current()->GetThreadList()->ForEach(ThreadListVisitor::Visit, &tlv);
 }
 
@@ -1531,7 +1531,7 @@
 }
 
 static int GetStackDepth(Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   struct CountStackDepthVisitor : public StackVisitor {
     CountStackDepthVisitor(const ManagedStack* stack,
                            const std::vector<TraceStackFrame>* trace_stack)
@@ -1547,7 +1547,7 @@
   };
 
   if (kIsDebugBuild) {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK(thread->IsSuspended());
   }
   CountStackDepthVisitor visitor(thread->GetManagedStack(), thread->GetTraceStack());
@@ -1565,7 +1565,7 @@
    public:
     GetFrameVisitor(const ManagedStack* stack, const std::vector<TraceStackFrame>* trace_stack,
                     size_t start_frame, size_t frame_count, JDWP::ExpandBuf* buf)
-        SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
         : StackVisitor(stack, trace_stack, NULL), depth_(0),
           start_frame_(start_frame), frame_count_(frame_count), buf_(buf) {
       expandBufAdd4BE(buf_, frame_count_);
@@ -1644,7 +1644,7 @@
 void Dbg::ResumeThread(JDWP::ObjectId threadId) {
   ScopedObjectAccessUnchecked soa(Thread::Current());
   Object* peer = gRegistry->Get<Object*>(threadId);
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Thread* thread = Thread::FromManagedThread(soa, peer);
   if (thread == NULL) {
     LOG(WARNING) << "No such thread for resume: " << peer;
@@ -1652,7 +1652,7 @@
   }
   bool needs_resume;
   {
-    MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu2(*Locks::thread_suspend_count_lock_);
     needs_resume = thread->GetSuspendCount() > 0;
   }
   if (needs_resume) {
@@ -1667,7 +1667,7 @@
 struct GetThisVisitor : public StackVisitor {
   GetThisVisitor(const ManagedStack* stack, const std::vector<TraceStackFrame>* trace_stack,
                  Context* context, JDWP::FrameId frameId)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : StackVisitor(stack, trace_stack, context), this_object(NULL), frame_id(frameId) {}
 
   // TODO: Enable annotalysis. We know lock is held in constructor, but abstraction confuses
@@ -1691,7 +1691,7 @@
 };
 
 static Object* GetThis(Thread* self, Method* m, size_t frame_id)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // TODO: should we return the 'this' we passed through to non-static native methods?
   if (m->IsNative() || m->IsStatic()) {
     return NULL;
@@ -1708,12 +1708,12 @@
   ScopedObjectAccessUnchecked soa(Thread::Current());
   Thread* thread;
   {
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
     thread = DecodeThread(soa, thread_id);
     if (thread == NULL) {
       return JDWP::ERR_INVALID_THREAD;
     }
-    MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu2(*Locks::thread_suspend_count_lock_);
     if (!thread->IsSuspended()) {
       return JDWP::ERR_THREAD_NOT_SUSPENDED;
     }
@@ -1731,7 +1731,7 @@
     GetLocalVisitor(const ManagedStack* stack, const std::vector<TraceStackFrame>* trace_stack,
                     Context* context, JDWP::FrameId frameId, int slot, JDWP::JdwpTag tag,
                     uint8_t* buf, size_t width)
-        SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
         : StackVisitor(stack, trace_stack, context), frame_id_(frameId), slot_(slot), tag_(tag),
           buf_(buf), width_(width) {}
 
@@ -1850,7 +1850,7 @@
     SetLocalVisitor(const ManagedStack* stack, const std::vector<TraceStackFrame>* trace_stack, Context* context,
                     JDWP::FrameId frame_id, int slot, JDWP::JdwpTag tag, uint64_t value,
                     size_t width)
-        SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
         : StackVisitor(stack, trace_stack, context),
           frame_id_(frame_id), slot_(slot), tag_(tag), value_(value), width_(width) {}
 
@@ -2139,7 +2139,7 @@
     SingleStepStackVisitor(const ManagedStack* stack,
                            const std::vector<TraceStackFrame>* trace_stack)
         EXCLUSIVE_LOCKS_REQUIRED(gBreakpointsLock)
-        SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
         : StackVisitor(stack, trace_stack, NULL) {
       gBreakpointsLock.AssertHeld();
       gSingleStepControl.method = NULL;
@@ -2299,7 +2299,7 @@
   Thread* self = Thread::Current();
   {
     ScopedObjectAccessUnchecked soa(self);
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
     targetThread = DecodeThread(soa, threadId);
     if (targetThread == NULL) {
       LOG(ERROR) << "InvokeMethod request for non-existent thread " << threadId;
@@ -2327,7 +2327,7 @@
      */
     int suspend_count;
     {
-      MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+      MutexLock mu2(*Locks::thread_suspend_count_lock_);
       suspend_count = targetThread->GetSuspendCount();
     }
     if (suspend_count > 1) {
@@ -2624,7 +2624,7 @@
 
   Thread* self = Thread::Current();
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     if (self->GetState() != kRunnable) {
       LOG(ERROR) << "DDM broadcast in thread state " << self->GetState();
       /* try anyway? */
@@ -2692,7 +2692,7 @@
     SuspendVM();
     std::list<Thread*> threads;
     {
-      MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+      MutexLock mu(*Locks::thread_list_lock_);
       threads = Runtime::Current()->GetThreadList()->GetList();
     }
     {
@@ -2885,7 +2885,7 @@
     needHeader_ = false;
   }
 
-  void Flush() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void Flush() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     // Patch the "length of piece" field.
     CHECK_LE(&buf_[0], pieceLenField_);
     CHECK_LE(pieceLenField_, p_);
@@ -2896,8 +2896,8 @@
   }
 
   static void HeapChunkCallback(void* start, void* end, size_t used_bytes, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_,
+                            Locks::mutator_lock_) {
     reinterpret_cast<HeapChunkContext*>(arg)->HeapChunkCallback(start, end, used_bytes);
   }
 
@@ -2913,8 +2913,8 @@
   }
 
   void HeapChunkCallback(void* start, void* /*end*/, size_t used_bytes)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_,
+                            Locks::mutator_lock_) {
     // Note: heap call backs cannot manipulate the heap upon which they are crawling, care is taken
     // in the following code not to allocate memory, by ensuring buf_ is of the correct size
     if (used_bytes == 0) {
@@ -2967,7 +2967,7 @@
   }
 
   void AppendChunk(uint8_t state, void* ptr, size_t length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     // Make sure there's enough room left in the buffer.
     // We need to use two bytes for every fractional 256 allocation units used by the chunk plus
     // 17 bytes for any header.
@@ -2997,7 +2997,7 @@
   }
 
   uint8_t ExamineObject(const Object* o, bool is_native_heap)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
     if (o == NULL) {
       return HPSG_STATE(SOLIDITY_FREE, 0);
     }
@@ -3089,7 +3089,7 @@
     const Spaces& spaces = heap->GetSpaces();
     for (Spaces::const_iterator cur = spaces.begin(); cur != spaces.end(); ++cur) {
       if ((*cur)->IsAllocSpace()) {
-        ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+        ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
         (*cur)->AsAllocSpace()->Walk(HeapChunkContext::HeapChunkCallback, &context);
       }
     }
@@ -3119,7 +3119,7 @@
 struct AllocRecordStackVisitor : public StackVisitor {
   AllocRecordStackVisitor(const ManagedStack* stack,
                           const std::vector<TraceStackFrame>* trace_stack, AllocRecord* record)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : StackVisitor(stack, trace_stack, NULL), record(record), depth(0) {}
 
   // TODO: Enable annotalysis. We know lock is held in constructor, but abstraction confuses
diff --git a/src/debugger.h b/src/debugger.h
index 6e82001..43590f8 100644
--- a/src/debugger.h
+++ b/src/debugger.h
@@ -81,7 +81,7 @@
   static void StopJdwp();
 
   // Invoked by the GC in case we need to keep DDMS informed.
-  static void GcDidFinish() LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+  static void GcDidFinish() LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   // Return the DebugInvokeReq for the current thread.
   static DebugInvokeReq* GetInvokeReq();
@@ -124,105 +124,105 @@
    * Class, Object, Array
    */
   static std::string GetClassName(JDWP::RefTypeId id)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError GetClassObject(JDWP::RefTypeId id, JDWP::ObjectId& classObjectId)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError GetSuperclass(JDWP::RefTypeId id, JDWP::RefTypeId& superclassId)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError GetClassLoader(JDWP::RefTypeId id, JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError GetModifiers(JDWP::RefTypeId id, JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError GetReflectedType(JDWP::RefTypeId classId, JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void GetClassList(std::vector<JDWP::RefTypeId>& classes)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError GetClassInfo(JDWP::RefTypeId classId, JDWP::JdwpTypeTag* pTypeTag,
                                       uint32_t* pStatus, std::string* pDescriptor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void FindLoadedClassBySignature(const char* descriptor, std::vector<JDWP::RefTypeId>& ids)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError GetReferenceType(JDWP::ObjectId objectId, JDWP::ExpandBuf* pReply);
   static JDWP::JdwpError GetSignature(JDWP::RefTypeId refTypeId, std::string& signature)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError GetSourceFile(JDWP::RefTypeId refTypeId, std::string& source_file)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError GetObjectTag(JDWP::ObjectId objectId, uint8_t& tag)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static size_t GetTagWidth(JDWP::JdwpTag tag);
 
   static JDWP::JdwpError GetArrayLength(JDWP::ObjectId arrayId, int& length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError OutputArray(JDWP::ObjectId arrayId, int firstIndex, int count,
                                      JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError SetArrayElements(JDWP::ObjectId arrayId, int firstIndex, int count,
                                           const uint8_t* buf)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static JDWP::ObjectId CreateString(const std::string& str)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError CreateObject(JDWP::RefTypeId classId, JDWP::ObjectId& new_object)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError CreateArrayObject(JDWP::RefTypeId arrayTypeId, uint32_t length,
                                            JDWP::ObjectId& new_array)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static bool MatchType(JDWP::RefTypeId instClassId, JDWP::RefTypeId classId)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Method and Field
    */
   static std::string GetMethodName(JDWP::RefTypeId refTypeId, JDWP::MethodId id)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError OutputDeclaredFields(JDWP::RefTypeId refTypeId, bool withGeneric,
                                               JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError OutputDeclaredMethods(JDWP::RefTypeId refTypeId, bool withGeneric,
                                                JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError OutputDeclaredInterfaces(JDWP::RefTypeId refTypeId,
                                                   JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void OutputLineTable(JDWP::RefTypeId refTypeId, JDWP::MethodId methodId,
                               JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void OutputVariableTable(JDWP::RefTypeId refTypeId, JDWP::MethodId id, bool withGeneric,
                                   JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static JDWP::JdwpTag GetFieldBasicTag(JDWP::FieldId fieldId)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpTag GetStaticFieldBasicTag(JDWP::FieldId fieldId)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);;
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);;
   static JDWP::JdwpError GetFieldValue(JDWP::ObjectId objectId, JDWP::FieldId fieldId,
                                        JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError SetFieldValue(JDWP::ObjectId objectId, JDWP::FieldId fieldId,
                                        uint64_t value, int width)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError GetStaticFieldValue(JDWP::RefTypeId refTypeId, JDWP::FieldId fieldId,
                                              JDWP::ExpandBuf* pReply)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError SetStaticFieldValue(JDWP::FieldId fieldId, uint64_t value, int width)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static std::string StringToUtf8(JDWP::ObjectId strId)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Thread, ThreadGroup, Frame
    */
   static bool GetThreadName(JDWP::ObjectId threadId, std::string& name)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
+      LOCKS_EXCLUDED(Locks::thread_list_lock_);
   static JDWP::JdwpError GetThreadGroup(JDWP::ObjectId threadId, JDWP::ExpandBuf* pReply);
   static std::string GetThreadGroupName(JDWP::ObjectId threadGroupId);
   static JDWP::ObjectId GetThreadGroupParent(JDWP::ObjectId threadGroupId)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::ObjectId GetSystemThreadGroupId()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::ObjectId GetMainThreadGroupId();
 
   static bool GetThreadStatus(JDWP::ObjectId threadId, JDWP::JdwpThreadStatus* pThreadStatus, JDWP::JdwpSuspendStatus* pSuspendStatus);
@@ -234,43 +234,43 @@
   // Fills 'thread_ids' with the threads in the given thread group. If thread_group_id == 0,
   // returns all threads.
   static void GetThreads(JDWP::ObjectId thread_group_id, std::vector<JDWP::ObjectId>& thread_ids)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void GetChildThreadGroups(JDWP::ObjectId thread_group_id, std::vector<JDWP::ObjectId>& child_thread_group_ids);
 
   static int GetThreadFrameCount(JDWP::ObjectId threadId);
   static JDWP::JdwpError GetThreadFrames(JDWP::ObjectId thread_id, size_t start_frame,
                                          size_t frame_count, JDWP::ExpandBuf* buf)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static JDWP::ObjectId GetThreadSelfId()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void SuspendVM()
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_);
   static void ResumeVM();
   static JDWP::JdwpError SuspendThread(JDWP::ObjectId threadId, bool request_suspension = true)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_,
-                     GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_,
+                     Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_);
 
   static void ResumeThread(JDWP::ObjectId threadId)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void SuspendSelf();
 
   static JDWP::JdwpError GetThisObject(JDWP::ObjectId thread_id, JDWP::FrameId frame_id,
                                        JDWP::ObjectId* result)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void GetLocalValue(JDWP::ObjectId threadId, JDWP::FrameId frameId, int slot,
                             JDWP::JdwpTag tag, uint8_t* buf, size_t expectedLen)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void SetLocalValue(JDWP::ObjectId threadId, JDWP::FrameId frameId, int slot,
                             JDWP::JdwpTag tag, uint64_t value, size_t width)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Debugger notification
@@ -282,29 +282,29 @@
     kMethodExit     = 0x08,
   };
   static void PostLocationEvent(const Method* method, int pcOffset, Object* thisPtr, int eventFlags)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void PostException(Thread* thread, JDWP::FrameId throw_frame_id, Method* throw_method,
                             uint32_t throw_dex_pc, Method* catch_method, uint32_t catch_dex_pc,
                             Throwable* exception)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void PostThreadStart(Thread* t)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void PostThreadDeath(Thread* t)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void PostClassPrepare(Class* c)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void UpdateDebugger(int32_t dex_pc, Thread* self)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void WatchLocation(const JDWP::JdwpLocation* pLoc)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void UnwatchLocation(const JDWP::JdwpLocation* pLoc)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static JDWP::JdwpError ConfigureStep(JDWP::ObjectId threadId, JDWP::JdwpStepSize size,
                                        JDWP::JdwpStepDepth depth)
       LOCKS_EXCLUDED(gBreakpointsLock)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void UnconfigureStep(JDWP::ObjectId threadId);
 
   static JDWP::JdwpError InvokeMethod(JDWP::ObjectId threadId, JDWP::ObjectId objectId,
@@ -313,9 +313,9 @@
                                       JDWP::JdwpTag* arg_types, uint32_t options,
                                       JDWP::JdwpTag* pResultTag, uint64_t* pResultValue,
                                       JDWP::ObjectId* pExceptObj)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void ExecuteMethod(DebugInvokeReq* pReq);
 
   /* perform "late registration" of an object ID */
@@ -325,27 +325,27 @@
    * DDM support.
    */
   static void DdmSendThreadNotification(Thread* t, uint32_t type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void DdmSetThreadNotification(bool enable);
   static bool DdmHandlePacket(const uint8_t* buf, int dataLen, uint8_t** pReplyBuf, int* pReplyLen);
-  static void DdmConnected() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
-  static void DdmDisconnected() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  static void DdmConnected() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+  static void DdmDisconnected() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void DdmSendChunk(uint32_t type, const std::vector<uint8_t>& bytes)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void DdmSendChunk(uint32_t type, size_t len, const uint8_t* buf)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void DdmSendChunkV(uint32_t type, const iovec* iov, int iov_count)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Recent allocation tracking support.
    */
   static void RecordAllocation(Class* type, size_t byte_count)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void SetAllocTrackingEnabled(bool enabled);
   static inline bool IsAllocTrackingEnabled() { return recent_allocation_records_ != NULL; }
   static jbyteArray GetRecentAllocations()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void DumpRecentAllocations();
 
   enum HpifWhen {
@@ -355,7 +355,7 @@
     HPIF_WHEN_EVERY_GC = 3
   };
   static int DdmHandleHpifChunk(HpifWhen when)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   enum HpsgWhen {
     HPSG_WHEN_NEVER = 0,
@@ -368,14 +368,14 @@
   static bool DdmHandleHpsgNhsgChunk(HpsgWhen when, HpsgWhat what, bool native);
 
   static void DdmSendHeapInfo(HpifWhen reason)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void DdmSendHeapSegments(bool native)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
  private:
-  static void DdmBroadcast(bool) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  static void DdmBroadcast(bool) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void PostThreadStartOrStop(Thread*, uint32_t)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static AllocRecord* recent_allocation_records_;
 };
diff --git a/src/dex2oat.cc b/src/dex2oat.cc
index b68a75b..2a6a220 100644
--- a/src/dex2oat.cc
+++ b/src/dex2oat.cc
@@ -123,7 +123,7 @@
  public:
   static bool Create(Dex2Oat** p_dex2oat, Runtime::Options& options, InstructionSet instruction_set,
                          size_t thread_count, bool support_debugging)
-      SHARED_TRYLOCK_FUNCTION(true, GlobalSynchronization::mutator_lock_) {
+      SHARED_TRYLOCK_FUNCTION(true, Locks::mutator_lock_) {
     if (!CreateRuntime(options, instruction_set)) {
       *p_dex2oat = NULL;
       return false;
@@ -139,7 +139,7 @@
 
   // Make a list of descriptors for classes to include in the image
   const std::set<std::string>* GetImageClassDescriptors(const char* image_classes_filename)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     UniquePtr<std::ifstream> image_classes_file(new std::ifstream(image_classes_filename, std::ifstream::in));
     if (image_classes_file.get() == NULL) {
       LOG(ERROR) << "Failed to open image classes file " << image_classes_filename;
@@ -213,7 +213,7 @@
                                 const std::set<std::string>* image_classes,
                                 bool dump_stats,
                                 bool dump_timings)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     // SirtRef and ClassLoader creation needs to come after Runtime::Create
     jobject class_loader = NULL;
     if (!boot_image_option.empty()) {
@@ -279,7 +279,7 @@
                        const std::string& oat_filename,
                        const std::string& oat_location,
                        const Compiler& compiler)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+      LOCKS_EXCLUDED(Locks::mutator_lock_) {
     ImageWriter image_writer(image_classes);
     if (!image_writer.Write(image_filename, image_base, oat_filename, oat_location, compiler)) {
       LOG(ERROR) << "Failed to create image file " << image_filename;
@@ -299,7 +299,7 @@
   }
 
   static bool CreateRuntime(Runtime::Options& options, InstructionSet instruction_set)
-      SHARED_TRYLOCK_FUNCTION(true, GlobalSynchronization::mutator_lock_) {
+      SHARED_TRYLOCK_FUNCTION(true, Locks::mutator_lock_) {
     if (!Runtime::Create(options, false)) {
       LOG(ERROR) << "Failed to create runtime";
       return false;
@@ -333,7 +333,7 @@
 
   static void ResolveExceptionsForMethod(MethodHelper* mh,
                            std::set<std::pair<uint16_t, const DexFile*> >& exceptions_to_resolve)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile::CodeItem* code_item = mh->GetCodeItem();
     if (code_item == NULL) {
       return;  // native or abstract method
@@ -370,7 +370,7 @@
   }
 
   static bool ResolveCatchBlockExceptionsClassVisitor(Class* c, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     std::set<std::pair<uint16_t, const DexFile*> >* exceptions_to_resolve =
         reinterpret_cast<std::set<std::pair<uint16_t, const DexFile*> >*>(arg);
     MethodHelper mh;
@@ -388,7 +388,7 @@
   }
 
   static bool RecordImageClassesVisitor(Class* klass, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     std::set<std::string>* image_classes = reinterpret_cast<std::set<std::string>*>(arg);
     if (klass->IsArrayClass() || klass->IsPrimitive()) {
       return true;
diff --git a/src/dex_cache.h b/src/dex_cache.h
index b3c5ce6..a08c644 100644
--- a/src/dex_cache.h
+++ b/src/dex_cache.h
@@ -39,11 +39,11 @@
             ObjectArray<Method>* methods,
             ObjectArray<Field>* fields,
             ObjectArray<StaticStorageBase>* initialized_static_storage)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void Fixup(Method* trampoline) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void Fixup(Method* trampoline) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  String* GetLocation() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  String* GetLocation() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return Get(kLocation)->AsString();
   }
 
@@ -62,49 +62,49 @@
                         kResolvedMethods * sizeof(Object*));
   }
 
-  size_t NumStrings() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t NumStrings() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetStrings()->GetLength();
   }
 
-  size_t NumResolvedTypes() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t NumResolvedTypes() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetResolvedTypes()->GetLength();
   }
 
-  size_t NumResolvedMethods() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t NumResolvedMethods() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetResolvedMethods()->GetLength();
   }
 
-  size_t NumResolvedFields() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t NumResolvedFields() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetResolvedFields()->GetLength();
   }
 
   size_t NumInitializedStaticStorage() const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetInitializedStaticStorage()->GetLength();
   }
 
   String* GetResolvedString(uint32_t string_idx) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetStrings()->Get(string_idx);
   }
 
   void SetResolvedString(uint32_t string_idx, String* resolved)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     GetStrings()->Set(string_idx, resolved);
   }
 
   Class* GetResolvedType(uint32_t type_idx) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetResolvedTypes()->Get(type_idx);
   }
 
   void SetResolvedType(uint32_t type_idx, Class* resolved)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     GetResolvedTypes()->Set(type_idx, resolved);
   }
 
   Method* GetResolvedMethod(uint32_t method_idx) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method = GetResolvedMethods()->Get(method_idx);
     // Hide resolution trampoline methods from the caller
     if (method != NULL && method->GetDexMethodIndex() == DexFile::kDexNoIndex16) {
@@ -116,38 +116,38 @@
   }
 
   void SetResolvedMethod(uint32_t method_idx, Method* resolved)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     GetResolvedMethods()->Set(method_idx, resolved);
   }
 
   Field* GetResolvedField(uint32_t field_idx) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetResolvedFields()->Get(field_idx);
   }
 
   void SetResolvedField(uint32_t field_idx, Field* resolved)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     GetResolvedFields()->Set(field_idx, resolved);
   }
 
   ObjectArray<String>* GetStrings() const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return static_cast<ObjectArray<String>*>(GetNonNull(kStrings));
   }
   ObjectArray<Class>* GetResolvedTypes() const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return static_cast<ObjectArray<Class>*>(GetNonNull(kResolvedTypes));
   }
   ObjectArray<Method>* GetResolvedMethods() const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return static_cast<ObjectArray<Method>*>(GetNonNull(kResolvedMethods));
   }
   ObjectArray<Field>* GetResolvedFields() const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return static_cast<ObjectArray<Field>*>(GetNonNull(kResolvedFields));
   }
   ObjectArray<StaticStorageBase>* GetInitializedStaticStorage() const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return static_cast<ObjectArray<StaticStorageBase>*>(GetNonNull(kInitializedStaticStorage));
   }
 
@@ -167,7 +167,7 @@
   };
 
   Object* GetNonNull(ArrayIndex array_index) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Object* obj = Get(array_index);
     DCHECK(obj != NULL);
     return obj;
diff --git a/src/dex_file.h b/src/dex_file.h
index 99a748d..7d39945 100644
--- a/src/dex_file.h
+++ b/src/dex_file.h
@@ -776,7 +776,7 @@
   //
   // This is used by runtime; therefore use art::Method not art::DexFile::Method.
   int32_t GetLineNumFromPC(const Method* method, uint32_t rel_pc) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void DecodeDebugInfo(const CodeItem* code_item, bool is_static, uint32_t method_idx,
                        DexDebugNewPositionCb position_cb, DexDebugNewLocalCb local_cb,
@@ -1125,10 +1125,10 @@
  public:
   EncodedStaticFieldValueIterator(const DexFile& dex_file, DexCache* dex_cache,
                                   ClassLinker* linker, const DexFile::ClassDef& class_def)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void ReadValueToField(Field* field) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool HasNext() { return pos_ < array_size_; }
 
diff --git a/src/heap.cc b/src/heap.cc
index 47473e3..d8f55ab 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -273,7 +273,7 @@
 };
 
 void Heap::AddSpace(Space* space) {
-  WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+  WriterMutexLock mu(*Locks::heap_bitmap_lock_);
   DCHECK(space != NULL);
   DCHECK(space->GetLiveBitmap() != NULL);
   live_bitmap_->AddSpaceBitmap(space->GetLiveBitmap());
@@ -366,7 +366,7 @@
   Object* obj = Allocate(alloc_space_, byte_count);
   if (LIKELY(obj != NULL)) {
 #if VERIFY_OBJECT_ENABLED
-    WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+    WriterMutexLock mu(*Locks::heap_bitmap_lock_);
     // Verify objects doesn't like objects in allocation stack not being marked as live.
     live_bitmap_->Set(obj);
 #endif
@@ -426,7 +426,7 @@
 }
 
 bool Heap::IsLiveObjectLocked(const Object* obj) {
-  GlobalSynchronization::heap_bitmap_lock_->AssertReaderHeld();
+  Locks::heap_bitmap_lock_->AssertReaderHeld();
   return IsHeapAddress(obj) && GetLiveBitmap()->Test(obj);
 }
 
@@ -489,7 +489,7 @@
 }
 
 void Heap::VerifyHeap() {
-  ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+  ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
   GetLiveBitmap()->Walk(Heap::VerificationCallback, this);
 }
 
@@ -546,7 +546,7 @@
   // done in the runnable state where suspension is expected.
 #ifndef NDEBUG
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_EQ(self->GetState(), kRunnable);
   }
   self->AssertThreadSuspensionIsAllowable();
@@ -660,7 +660,7 @@
 class InstanceCounter {
  public:
   InstanceCounter(Class* c, bool count_assignable)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : class_(c), count_assignable_(count_assignable), count_(0) {
 
   }
@@ -670,12 +670,12 @@
   }
 
   static void Callback(Object* o, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     reinterpret_cast<InstanceCounter*>(arg)->VisitInstance(o);
   }
 
  private:
-  void VisitInstance(Object* o) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void VisitInstance(Object* o) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Class* instance_class = o->GetClass();
     if (count_assignable_) {
       if (instance_class == class_) {
@@ -694,7 +694,7 @@
 };
 
 int64_t Heap::CountInstances(Class* c, bool count_assignable) {
-  ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+  ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
   InstanceCounter counter(c, count_assignable);
   GetLiveBitmap()->Walk(InstanceCounter::Callback, &counter);
   return counter.GetCount();
@@ -722,7 +722,7 @@
 
   {
     // Flush the alloc stack.
-    WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+    WriterMutexLock mu(*Locks::heap_bitmap_lock_);
     FlushAllocStack();
   }
 
@@ -806,10 +806,10 @@
 }
 
 void Heap::CollectGarbageInternal(GcType gc_type, bool clear_soft_references) {
-  GlobalSynchronization::mutator_lock_->AssertNotHeld();
+  Locks::mutator_lock_->AssertNotHeld();
 #ifndef NDEBUG
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_EQ(Thread::Current()->GetState(), kWaitingPerformingGc);
   }
 #endif
@@ -868,7 +868,7 @@
   ThreadList* thread_list = Runtime::Current()->GetThreadList();
   thread_list->SuspendAll();
   timings.AddSplit("SuspendAll");
-  GlobalSynchronization::mutator_lock_->AssertExclusiveHeld();
+  Locks::mutator_lock_->AssertExclusiveHeld();
 
   size_t bytes_freed = 0;
   Object* cleared_references = NULL;
@@ -880,7 +880,7 @@
 
     // Pre verify the heap
     if (pre_gc_verify_heap_) {
-      WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      WriterMutexLock mu(*Locks::heap_bitmap_lock_);
       VerifyHeapReferences(std::string("Pre ") + gc_type_str.str() + "Gc");
       timings.AddSplit("VerifyHeapReferencesPreGC");
     }
@@ -918,7 +918,7 @@
       }
     }
 
-    WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+    WriterMutexLock mu(*Locks::heap_bitmap_lock_);
     if (gc_type == GC_PARTIAL) {
       // Copy the mark bits over from the live bits, do this as early as possible or else we can
       // accidentally un-mark roots.
@@ -1007,7 +1007,7 @@
 
   // Post gc verify the heap
   if (post_gc_verify_heap_) {
-    WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+    WriterMutexLock mu(*Locks::heap_bitmap_lock_);
     VerifyHeapReferences(std::string("Post ") + gc_type_str.str() + "Gc");
     timings.AddSplit("VerifyHeapReferencesPostGC");
   }
@@ -1081,8 +1081,8 @@
 class VerifyReferenceVisitor {
  public:
   VerifyReferenceVisitor(Heap* heap, bool* failed)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_,
-                            GlobalSynchronization::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_,
+                            Locks::heap_bitmap_lock_)
       : heap_(heap),
         failed_(failed) {
   }
@@ -1183,8 +1183,7 @@
   }
 
   void operator ()(const Object* obj) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_,
-          GlobalSynchronization::heap_bitmap_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) {
     VerifyReferenceVisitor visitor(heap_, const_cast<bool*>(&failed_));
     MarkSweep::VisitObjectReferences(obj, visitor);
   }
@@ -1200,7 +1199,7 @@
 
 // Must do this with mutators suspended since we are directly accessing the allocation stacks.
 void Heap::VerifyHeapReferences(const std::string& phase) {
-  GlobalSynchronization::mutator_lock_->AssertExclusiveHeld();
+  Locks::mutator_lock_->AssertExclusiveHeld();
   // Lets sort our allocation stacks so that we can efficiently binary search them.
   std::sort(allocation_stack_->Begin(), allocation_stack_->End());
   std::sort(live_stack_->Begin(), live_stack_->End());
@@ -1220,7 +1219,7 @@
   // these bitmaps. Doing this enables us to sweep with the heap unlocked since new allocations
   // set the live bit, but since we have the bitmaps reversed at this point, this sets the mark bit
   // instead, resulting in no new allocated objects being incorrectly freed by sweep.
-  WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+  WriterMutexLock mu(*Locks::heap_bitmap_lock_);
   for (Spaces::iterator it = spaces_.begin(); it != spaces_.end(); ++it) {
     Space* space = *it;
     // We never allocate into zygote spaces.
@@ -1242,7 +1241,7 @@
   ThreadList* thread_list = Runtime::Current()->GetThreadList();
   thread_list->SuspendAll();
   timings.AddSplit("SuspendAll");
-  GlobalSynchronization::mutator_lock_->AssertExclusiveHeld();
+  Locks::mutator_lock_->AssertExclusiveHeld();
 
   size_t bytes_freed = 0;
   Object* cleared_references = NULL;
@@ -1255,7 +1254,7 @@
 
     // Pre verify the heap
     if (pre_gc_verify_heap_) {
-      WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      WriterMutexLock mu(*Locks::heap_bitmap_lock_);
       VerifyHeapReferences(std::string("Pre ") + gc_type_str.str() + "Gc");
       timings.AddSplit("VerifyHeapReferencesPreGC");
     }
@@ -1294,7 +1293,7 @@
     }
 
     {
-      WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      WriterMutexLock mu(*Locks::heap_bitmap_lock_);
 
       if (gc_type == GC_PARTIAL) {
         // Copy the mark bits over from the live bits, do this as early as possible or else we can
@@ -1343,11 +1342,11 @@
     // Allow mutators to go again, acquire share on mutator_lock_ to continue.
     thread_list->ResumeAll();
     {
-      ReaderMutexLock reader_lock(*GlobalSynchronization::mutator_lock_);
+      ReaderMutexLock reader_lock(*Locks::mutator_lock_);
       root_end = NanoTime();
       timings.AddSplit("RootEnd");
 
-      WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      WriterMutexLock mu(*Locks::heap_bitmap_lock_);
       UpdateAndMarkModUnion(timings, gc_type);
       if (gc_type != GC_STICKY) {
         // Recursively mark all the non-image bits set in the mark bitmap.
@@ -1361,10 +1360,10 @@
     dirty_begin = NanoTime();
     thread_list->SuspendAll();
     timings.AddSplit("ReSuspend");
-    GlobalSynchronization::mutator_lock_->AssertExclusiveHeld();
+    Locks::mutator_lock_->AssertExclusiveHeld();
 
     {
-      WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      WriterMutexLock mu(*Locks::heap_bitmap_lock_);
 
       // Re-mark root set.
       mark_sweep.ReMarkRoots();
@@ -1376,7 +1375,7 @@
     }
 
     {
-      ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
       mark_sweep.ProcessReferences(clear_soft_references);
       timings.AddSplit("ProcessReferences");
 
@@ -1395,7 +1394,7 @@
 
     if (kIsDebugBuild) {
       // Verify that we only reach marked objects from the image space.
-      ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
       mark_sweep.VerifyImageRoots();
       timings.AddSplit("VerifyImageRoots");
     }
@@ -1411,18 +1410,18 @@
     // If we are going to do post Gc verification, lets keep the mutators paused since we don't
     // want them to touch dead objects before we find these in verification.
     if (post_gc_verify_heap_) {
-      WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      WriterMutexLock mu(*Locks::heap_bitmap_lock_);
       VerifyHeapReferences(std::string("Post ") + gc_type_str.str() + "Gc");
       timings.AddSplit("VerifyHeapReferencesPostGC");
     }
 
     thread_list->ResumeAll();
     dirty_end = NanoTime();
-    GlobalSynchronization::mutator_lock_->AssertNotHeld();
+    Locks::mutator_lock_->AssertNotHeld();
 
     {
       // TODO: this lock shouldn't be necessary (it's why we did the bitmap flip above).
-      WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      WriterMutexLock mu(*Locks::heap_bitmap_lock_);
       if (gc_type != GC_STICKY) {
         mark_sweep.Sweep(gc_type == GC_PARTIAL, swap);
       } else {
diff --git a/src/heap.h b/src/heap.h
index 23f2ac3..104cbdf 100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -90,7 +90,7 @@
 
   // Allocates and initializes storage for an object instance.
   Object* AllocObject(Class* klass, size_t num_bytes)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Check sanity of given reference. Requires the heap lock.
 #if VERIFY_OBJECT_ENABLED
@@ -103,8 +103,8 @@
   void VerifyHeap();
   static void RootMatchesObjectVisitor(const Object* root, void* arg);
   void VerifyHeapReferences(const std::string& phase)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // A weaker test than IsLiveObject or VerifyObject that doesn't require the heap lock,
   // and doesn't abort on error, allowing the caller to report more
@@ -114,11 +114,11 @@
   // Returns true if 'obj' is a live heap object, false otherwise (including for invalid addresses).
   // Requires the heap lock to be held.
   bool IsLiveObjectLocked(const Object* obj)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Initiates an explicit garbage collection.
   void CollectGarbage(bool clear_soft_references)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   // Does a concurrent GC, should only be called by the GC daemon thread
   // through runtime.
@@ -133,8 +133,8 @@
 
   // Implements VMDebug.countInstancesOfClass.
   int64_t CountInstances(Class* c, bool count_assignable)
-      LOCKS_EXCLUDED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Removes the growth limit on the alloc space so it may grow to its maximum capacity. Used to
   // implement dalvik.system.VMRuntime.clearGrowthLimit.
@@ -244,11 +244,11 @@
 
   void Trim();
 
-  HeapBitmap* GetLiveBitmap() SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) {
+  HeapBitmap* GetLiveBitmap() SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
     return live_bitmap_.get();
   }
 
-  HeapBitmap* GetMarkBitmap() SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) {
+  HeapBitmap* GetMarkBitmap() SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
     return mark_bitmap_.get();
   }
 
@@ -256,7 +256,7 @@
 
   // Mark and empty stack.
   void FlushAllocStack()
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Mark all the objects in the allocation stack as live.
   void MarkStackAsLive(MarkStack* alloc_stack);
@@ -269,7 +269,7 @@
 
   // Update and mark mod union table based on gc type.
   void UpdateAndMarkModUnion(TimingLogger& timings, GcType gc_type)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // DEPRECATED: Should remove in "near" future when support for multiple image spaces is added.
   // Assumes there is only one image space.
@@ -280,8 +280,8 @@
  private:
   // Allocates uninitialized storage.
   Object* Allocate(AllocSpace* space, size_t num_bytes)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Pushes a list of cleared references out to the managed heap.
   void EnqueueClearedReferences(Object** cleared_references);
@@ -290,19 +290,19 @@
   void RequestConcurrentGC();
 
   void RecordAllocation(AllocSpace* space, const Object* object)
-      LOCKS_EXCLUDED(GlobalSynchronization::heap_bitmap_lock_);
+      LOCKS_EXCLUDED(Locks::heap_bitmap_lock_);
 
   void CollectGarbageInternal(GcType gc_plan, bool clear_soft_references)
       LOCKS_EXCLUDED(gc_complete_lock_,
-                     GlobalSynchronization::heap_bitmap_lock_,
-                     GlobalSynchronization::mutator_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+                     Locks::heap_bitmap_lock_,
+                     Locks::mutator_lock_,
+                     Locks::thread_suspend_count_lock_);
   void CollectGarbageMarkSweepPlan(GcType gc_plan, bool clear_soft_references)
-      LOCKS_EXCLUDED(GlobalSynchronization::heap_bitmap_lock_,
-                     GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::heap_bitmap_lock_,
+                     Locks::mutator_lock_);
   void CollectGarbageConcurrentMarkSweepPlan(GcType gc_plan, bool clear_soft_references)
-      LOCKS_EXCLUDED(GlobalSynchronization::heap_bitmap_lock_,
-                     GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::heap_bitmap_lock_,
+                     Locks::mutator_lock_);
 
   // Given the current contents of the alloc space, increase the allowed heap footprint to match
   // the target utilization ratio.  This should only be called immediately after a full garbage
@@ -311,7 +311,7 @@
 
   size_t GetPercentFree();
 
-  void AddSpace(Space* space) LOCKS_EXCLUDED(GlobalSynchronization::heap_bitmap_lock_);
+  void AddSpace(Space* space) LOCKS_EXCLUDED(Locks::heap_bitmap_lock_);
 
   // No thread saftey analysis since we call this everywhere and it is impossible to find a proper
   // lock ordering for it.
@@ -376,8 +376,8 @@
   // Last trim time
   uint64_t last_trim_time_;
 
-  UniquePtr<HeapBitmap> live_bitmap_ GUARDED_BY(GlobalSynchronization::heap_bitmap_lock_);
-  UniquePtr<HeapBitmap> mark_bitmap_ GUARDED_BY(GlobalSynchronization::heap_bitmap_lock_);
+  UniquePtr<HeapBitmap> live_bitmap_ GUARDED_BY(Locks::heap_bitmap_lock_);
+  UniquePtr<HeapBitmap> mark_bitmap_ GUARDED_BY(Locks::heap_bitmap_lock_);
 
   // True while the garbage collector is trying to signal the GC daemon thread.
   // This flag is needed to prevent recursion from occurring when the JNI calls
diff --git a/src/heap_bitmap.h b/src/heap_bitmap.h
index d202ae3..50ecc7a 100644
--- a/src/heap_bitmap.h
+++ b/src/heap_bitmap.h
@@ -26,14 +26,14 @@
   class HeapBitmap {
    public:
     bool Test(const Object* obj)
-        SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) {
+        SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
       SpaceBitmap* bitmap = GetSpaceBitmap(obj);
       DCHECK(bitmap != NULL);
       return bitmap->Test(obj);
     }
 
     void Clear(const Object* obj)
-        EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) {
+        EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
       SpaceBitmap* bitmap = GetSpaceBitmap(obj);
       DCHECK(bitmap != NULL)
         << "tried to clear object "
@@ -43,7 +43,7 @@
     }
 
     void Set(const Object* obj)
-        EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) {
+        EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
       SpaceBitmap* bitmap = GetSpaceBitmap(obj);
       DCHECK(bitmap != NULL)
         << "tried to mark object "
@@ -63,7 +63,7 @@
     }
 
     void Walk(SpaceBitmap::Callback* callback, void* arg)
-        SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) {
+        SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
       // TODO: C++0x auto
       for (Bitmaps::iterator it = bitmaps_.begin(); it!= bitmaps_.end(); ++it) {
         (*it)->Walk(callback, arg);
@@ -72,7 +72,7 @@
 
     template <typename Visitor>
     void Visit(const Visitor& visitor)
-        EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) {
+        EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
       // TODO: C++0x auto
       for (Bitmaps::iterator it = bitmaps_.begin(); it != bitmaps_.end(); ++it) {
         SpaceBitmap* bitmap = *it;
@@ -83,7 +83,7 @@
 
     // Find and replace a bitmap pointer, this is used by for the bitmap swapping in the GC.
     void ReplaceBitmap(SpaceBitmap* old_bitmap, SpaceBitmap* new_bitmap)
-        EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+        EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
     HeapBitmap(Heap* heap) : heap_(heap) {
 
diff --git a/src/hprof/hprof.cc b/src/hprof/hprof.cc
index 356c1fb..0cad709 100644
--- a/src/hprof/hprof.cc
+++ b/src/hprof/hprof.cc
@@ -402,17 +402,17 @@
   }
 
   void Dump()
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
-      LOCKS_EXCLUDED(GlobalSynchronization::heap_bitmap_lock_) {
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_)
+      LOCKS_EXCLUDED(Locks::heap_bitmap_lock_) {
     // Walk the roots and the heap.
     current_record_.StartNewRecord(body_fp_, HPROF_TAG_HEAP_DUMP_SEGMENT, HPROF_TIME);
     Runtime::Current()->VisitRoots(RootVisitor, this);
     {
-      WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      WriterMutexLock mu(*Locks::heap_bitmap_lock_);
       Runtime::Current()->GetHeap()->FlushAllocStack();
     }
     {
-      ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
       Runtime::Current()->GetHeap()->GetLiveBitmap()->Walk(HeapBitmapCallback, this);
     }
     current_record_.StartNewRecord(body_fp_, HPROF_TAG_HEAP_DUMP_END, HPROF_TIME);
@@ -474,28 +474,28 @@
 
  private:
   static void RootVisitor(const Object* obj, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK(arg != NULL);
     Hprof* hprof = reinterpret_cast<Hprof*>(arg);
     hprof->VisitRoot(obj);
   }
 
   static void HeapBitmapCallback(Object* obj, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK(obj != NULL);
     CHECK(arg != NULL);
     Hprof* hprof = reinterpret_cast<Hprof*>(arg);
     hprof->DumpHeapObject(obj);
   }
 
-  void VisitRoot(const Object* obj) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void VisitRoot(const Object* obj) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  int DumpHeapObject(Object* obj) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  int DumpHeapObject(Object* obj) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void Finish() {
   }
 
-  int WriteClassTable() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  int WriteClassTable() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     HprofRecord* rec = &current_record_;
     uint32_t nextSerialNumber = 1;
 
@@ -563,7 +563,7 @@
   int MarkRootObject(const Object* obj, jobject jniObj);
 
   HprofClassObjectId LookupClassId(Class* c)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (c == NULL) {
       // c is the superclass of java.lang.Object or a primitive
       return (HprofClassObjectId)0;
@@ -598,7 +598,7 @@
   }
 
   HprofStringId LookupClassNameId(const Class* c)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return LookupStringId(PrettyDescriptor(c));
   }
 
diff --git a/src/image.h b/src/image.h
index 253b762..399b143 100644
--- a/src/image.h
+++ b/src/image.h
@@ -95,7 +95,7 @@
   };
 
   Object* GetImageRoot(ImageRoot image_root) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetImageRoots()->Get(image_root);
   }
 
diff --git a/src/image_writer.cc b/src/image_writer.cc
index 0932c30..d91fc59 100644
--- a/src/image_writer.cc
+++ b/src/image_writer.cc
@@ -189,10 +189,10 @@
 }
 
 void ImageWriter::ComputeEagerResolvedStrings()
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // TODO: Check image spaces only?
   Heap* heap = Runtime::Current()->GetHeap();
-  ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+  ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
   heap->FlushAllocStack();
   heap->GetLiveBitmap()->Walk(ComputeEagerResolvedStringsCallback, this);
 }
@@ -270,18 +270,18 @@
 }
 
 void ImageWriter::CheckNonImageClassesRemoved()
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (image_classes_ == NULL) {
     return;
   }
 
   Heap* heap = Runtime::Current()->GetHeap();
   {
-    WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+    WriterMutexLock mu(*Locks::heap_bitmap_lock_);
     heap->FlushAllocStack();
   }
 
-  ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+  ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
   heap->GetLiveBitmap()->Walk(CheckNonImageClassesRemovedCallback, this);
 }
 
@@ -394,7 +394,7 @@
 
   {
     Heap* heap = Runtime::Current()->GetHeap();
-    ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+    ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
     heap->FlushAllocStack();
   }
 
@@ -420,12 +420,12 @@
 }
 
 void ImageWriter::CopyAndFixupObjects()
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Heap* heap = Runtime::Current()->GetHeap();
   // TODO: heap validation can't handle this fix up pass
   heap->DisableObjectValidation();
   // TODO: Image spaces only?
-  ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+  ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
   heap->FlushAllocStack();
   heap->GetLiveBitmap()->Walk(CopyAndFixupObjectsCallback, this);
 }
@@ -604,7 +604,7 @@
 }
 
 static Method* GetReferrerMethod(const Compiler::PatchInformation* patch)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ScopedObjectAccessUnchecked soa(Thread::Current());
   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
   DexCache* dex_cache = class_linker->FindDexCache(patch->GetDexFile());
@@ -626,7 +626,7 @@
 }
 
 static Method* GetTargetMethod(const Compiler::PatchInformation* patch)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
   DexCache* dex_cache = class_linker->FindDexCache(patch->GetDexFile());
   Method* method = class_linker->ResolveMethod(patch->GetDexFile(),
diff --git a/src/image_writer.h b/src/image_writer.h
index f768d87..8e8d106 100644
--- a/src/image_writer.h
+++ b/src/image_writer.h
@@ -49,14 +49,14 @@
              const std::string& oat_filename,
              const std::string& oat_location,
              const Compiler& compiler)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
  private:
   bool AllocMemory();
 
   // we use the lock word to store the offset of the object in the image
   void AssignImageOffset(Object* object)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(object != NULL);
     SetImageOffset(object, image_end_);
     image_end_ += RoundUp(object->SizeOf(), 8);  // 64-bit alignment
@@ -108,55 +108,55 @@
     return oat_begin_ + offset;
   }
 
-  bool IsImageClass(const Class* klass) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool IsImageClass(const Class* klass) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void DumpImageClasses();
 
   void ComputeLazyFieldsForImageClasses()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static bool ComputeLazyFieldsForClassesVisitor(Class* klass, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Wire dex cache resolved strings to strings in the image to avoid runtime resolution
   void ComputeEagerResolvedStrings();
   static void ComputeEagerResolvedStringsCallback(Object* obj, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void PruneNonImageClasses() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void PruneNonImageClasses() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static bool NonImageClassesVisitor(Class* c, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void CheckNonImageClassesRemoved();
   static void CheckNonImageClassesRemovedCallback(Object* obj, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void CalculateNewObjectOffsets() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void CalculateNewObjectOffsets() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   ObjectArray<Object>* CreateImageRoots() const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void CalculateNewObjectOffsetsCallback(Object* obj, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void CopyAndFixupObjects();
   static void CopyAndFixupObjectsCallback(Object* obj, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void FixupClass(const Class* orig, Class* copy)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void FixupMethod(const Method* orig, Method* copy)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void FixupObject(const Object* orig, Object* copy)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void FixupObjectArray(const ObjectArray<Object>* orig, ObjectArray<Object>* copy)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void FixupInstanceFields(const Object* orig, Object* copy)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void FixupStaticFields(const Class* orig, Class* copy)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void FixupFields(const Object* orig, Object* copy, uint32_t ref_offsets, bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void PatchOatCodeAndMethods(const Compiler& compiler)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetPatchLocation(const Compiler::PatchInformation* patch, uint32_t value)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   SafeMap<const Object*, size_t> offsets_;
 
diff --git a/src/indirect_reference_table.h b/src/indirect_reference_table.h
index c3e17b0..48bd35b 100644
--- a/src/indirect_reference_table.h
+++ b/src/indirect_reference_table.h
@@ -258,7 +258,7 @@
    * failed during expansion).
    */
   IndirectRef Add(uint32_t cookie, const Object* obj)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Given an IndirectRef in the table, return the Object it refers to.
@@ -288,7 +288,7 @@
 
   void AssertEmpty();
 
-  void Dump(std::ostream& os) const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void Dump(std::ostream& os) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Return the #of entries in the entire table.  This includes holes, and
diff --git a/src/intern_table.h b/src/intern_table.h
index 0d9e097..6f56773 100644
--- a/src/intern_table.h
+++ b/src/intern_table.h
@@ -42,26 +42,26 @@
 
   // Interns a potentially new string in the 'strong' table. (See above.)
   String* InternStrong(int32_t utf16_length, const char* utf8_data)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Interns a potentially new string in the 'strong' table. (See above.)
   String* InternStrong(const char* utf8_data)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Interns a potentially new string in the 'strong' table. (See above.)
-  String* InternStrong(String* s) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  String* InternStrong(String* s) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Interns a potentially new string in the 'weak' table. (See above.)
-  String* InternWeak(String* s) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  String* InternWeak(String* s) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Register a String trusting that it is safe to intern.
   // Used when reinitializing InternTable from an image.
-  void RegisterStrong(String* s) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void RegisterStrong(String* s) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void SweepInternTableWeaks(Heap::IsMarkedTester is_marked, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
-  bool ContainsWeak(String* s) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool ContainsWeak(String* s) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   size_t Size() const;
 
@@ -73,10 +73,10 @@
   typedef std::multimap<int32_t, String*> Table;
 
   String* Insert(String* s, bool is_strong)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   String* Lookup(Table& table, String* s, uint32_t hash_code)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   String* Insert(Table& table, String* s, uint32_t hash_code);
   void Remove(Table& table, const String* s, uint32_t hash_code);
 
diff --git a/src/intern_table_test.cc b/src/intern_table_test.cc
index 0d46076..15fa259 100644
--- a/src/intern_table_test.cc
+++ b/src/intern_table_test.cc
@@ -102,7 +102,7 @@
   p.Expect(s0.get());
   p.Expect(s1.get());
   {
-    ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+    ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
     t.SweepInternTableWeaks(IsMarked, &p);
   }
 
diff --git a/src/jdwp/jdwp.h b/src/jdwp/jdwp.h
index 725e857..54e5cc7 100644
--- a/src/jdwp/jdwp.h
+++ b/src/jdwp/jdwp.h
@@ -79,7 +79,7 @@
   uint64_t dex_pc;
 };
 std::ostream& operator<<(std::ostream& os, const JdwpLocation& rhs)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 bool operator==(const JdwpLocation& lhs, const JdwpLocation& rhs);
 bool operator!=(const JdwpLocation& lhs, const JdwpLocation& rhs);
 
@@ -120,7 +120,7 @@
    * Returns a newly-allocated JdwpState struct on success, or NULL on failure.
    */
   static JdwpState* Create(const JdwpOptions* options)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   ~JdwpState();
 
@@ -180,7 +180,7 @@
    * The VM has finished initializing.  Only called when the debugger is
    * connected at the time initialization completes.
    */
-  bool PostVMStart() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool PostVMStart() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * A location of interest has been reached.  This is used for breakpoints,
@@ -193,7 +193,7 @@
    * "eventFlags" indicates the types of events that have occurred.
    */
   bool PostLocationEvent(const JdwpLocation* pLoc, ObjectId thisPtr, int eventFlags)
-     SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+     SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * An exception has been thrown.
@@ -202,20 +202,20 @@
    */
   bool PostException(const JdwpLocation* pThrowLoc, ObjectId excepId, RefTypeId excepClassId,
                      const JdwpLocation* pCatchLoc, ObjectId thisPtr)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * A thread has started or stopped.
    */
   bool PostThreadChange(ObjectId threadId, bool start)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Class has been prepared.
    */
   bool PostClassPrepare(JdwpTypeTag tag, RefTypeId refTypeId, const std::string& signature,
                         int status)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * The VM is about to stop.
@@ -223,13 +223,13 @@
   bool PostVMDeath();
 
   // Called if/when we realize we're talking to DDMS.
-  void NotifyDdmsActive() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void NotifyDdmsActive() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Send up a chunk of DDM data.
    */
   void DdmSendChunkV(uint32_t type, const iovec* iov, int iov_count)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Process a request from the debugger.
@@ -248,15 +248,15 @@
 
   void ResetState()
       LOCKS_EXCLUDED(event_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /* atomic ops to get next serial number */
   uint32_t NextRequestSerial();
   uint32_t NextEventSerial();
 
   void Run()
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_,
+                     Locks::thread_suspend_count_lock_);
 
   /*
    * Register an event by adding it to the event list.
@@ -266,45 +266,45 @@
    */
   JdwpError RegisterEvent(JdwpEvent* pEvent)
       LOCKS_EXCLUDED(event_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Unregister an event, given the requestId.
    */
   void UnregisterEventById(uint32_t requestId)
       LOCKS_EXCLUDED(event_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Unregister all events.
    */
   void UnregisterAll()
       LOCKS_EXCLUDED(event_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
  private:
   explicit JdwpState(const JdwpOptions* options);
   bool InvokeInProgress();
   bool IsConnected();
   void SuspendByPolicy(JdwpSuspendPolicy suspend_policy,  JDWP::ObjectId thread_self_id)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_);
   void SendRequestAndPossiblySuspend(ExpandBuf* pReq, JdwpSuspendPolicy suspend_policy,
                                      ObjectId threadId)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void CleanupMatchList(JdwpEvent** match_list,
                         int match_count)
       EXCLUSIVE_LOCKS_REQUIRED(event_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void EventFinish(ExpandBuf* pReq);
   void FindMatchingEvents(JdwpEventKind eventKind,
                           ModBasket* basket,
                           JdwpEvent** match_list,
                           int* pMatchCount)
       EXCLUSIVE_LOCKS_REQUIRED(event_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void UnregisterEvent(JdwpEvent* pEvent)
       EXCLUSIVE_LOCKS_REQUIRED(event_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
  public: // TODO: fix privacy
   const JdwpOptions* options_;
diff --git a/src/jdwp/jdwp_event.cc b/src/jdwp/jdwp_event.cc
index 0eb2930..4f11a65 100644
--- a/src/jdwp/jdwp_event.cc
+++ b/src/jdwp/jdwp_event.cc
@@ -375,7 +375,7 @@
  * need to do this even if later mods cause us to ignore the event.
  */
 static bool ModsMatch(JdwpEvent* pEvent, ModBasket* basket)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   JdwpEventMod* pMod = pEvent->mods;
 
   for (int i = pEvent->modCount; i > 0; i--, pMod++) {
diff --git a/src/jdwp/jdwp_handler.cc b/src/jdwp/jdwp_handler.cc
index fbe9192..07e47b5 100644
--- a/src/jdwp/jdwp_handler.cc
+++ b/src/jdwp/jdwp_handler.cc
@@ -92,7 +92,7 @@
 static JdwpError FinishInvoke(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply,
                               ObjectId thread_id, ObjectId object_id,
                               RefTypeId class_id, MethodId method_id, bool is_constructor)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   CHECK(!is_constructor || object_id != 0);
 
   uint32_t arg_count = Read4BE(&buf);
@@ -161,7 +161,7 @@
  * Request for version info.
  */
 static JdwpError VM_Version(JdwpState*, const uint8_t*, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   /* text information on runtime version */
   std::string version(StringPrintf("Android Runtime %s", Runtime::Current()->GetVersion()));
   expandBufAddUtf8String(pReply, version);
@@ -182,7 +182,7 @@
  * been loaded by multiple class loaders.
  */
 static JdwpError VM_ClassesBySignature(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   std::string classDescriptor(ReadNewUtf8String(&buf));
   VLOG(jdwp) << "  Req for class by signature '" << classDescriptor << "'";
 
@@ -215,7 +215,7 @@
  * to be suspended, and that violates some JDWP expectations.
  */
 static JdwpError VM_AllThreads(JdwpState*, const uint8_t*, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   std::vector<ObjectId> thread_ids;
   Dbg::GetThreads(0, thread_ids);
 
@@ -231,7 +231,7 @@
  * List all thread groups that do not have a parent.
  */
 static JdwpError VM_TopLevelThreadGroups(JdwpState*, const uint8_t*, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   /*
    * TODO: maintain a list of parentless thread groups in the VM.
    *
@@ -254,7 +254,7 @@
  * All IDs are 8 bytes.
  */
 static JdwpError VM_IDSizes(JdwpState*, const uint8_t*, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   expandBufAdd4BE(pReply, sizeof(FieldId));
   expandBufAdd4BE(pReply, sizeof(MethodId));
   expandBufAdd4BE(pReply, sizeof(ObjectId));
@@ -264,7 +264,7 @@
 }
 
 static JdwpError VM_Dispose(JdwpState*, const uint8_t*, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Dbg::Disposed();
   return ERR_NONE;
 }
@@ -276,7 +276,7 @@
  * This needs to increment the "suspend count" on all threads.
  */
 static JdwpError VM_Suspend(JdwpState*, const uint8_t*, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Dbg::SuspendVM();
   return ERR_NONE;
 }
@@ -285,7 +285,7 @@
  * Resume execution.  Decrements the "suspend count" of all threads.
  */
 static JdwpError VM_Resume(JdwpState*, const uint8_t*, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Dbg::ResumeVM();
   return ERR_NONE;
 }
@@ -294,7 +294,7 @@
  * The debugger wants the entire VM to exit.
  */
 static JdwpError VM_Exit(JdwpState*, const uint8_t* buf, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   uint32_t exitCode = Get4BE(buf);
 
   LOG(WARNING) << "Debugger is telling the VM to exit with code=" << exitCode;
@@ -310,7 +310,7 @@
  * string "java.util.Arrays".)
  */
 static JdwpError VM_CreateString(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   std::string str(ReadNewUtf8String(&buf));
   VLOG(jdwp) << "  Req to create string '" << str << "'";
   ObjectId stringId = Dbg::CreateString(str);
@@ -325,7 +325,7 @@
  * Tell the debugger what we are capable of.
  */
 static JdwpError VM_Capabilities(JdwpState*, const uint8_t*, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   expandBufAdd1(pReply, false);   /* canWatchFieldModification */
   expandBufAdd1(pReply, false);   /* canWatchFieldAccess */
   expandBufAdd1(pReply, false);   /* canGetBytecodes */
@@ -337,7 +337,7 @@
 }
 
 static JdwpError VM_ClassPaths(JdwpState*, const uint8_t*, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   expandBufAddUtf8String(pReply, "/");
 
   std::vector<std::string> class_path;
@@ -363,7 +363,7 @@
  * Currently does nothing.
  */
 static JdwpError VM_DisposeObjects(JdwpState*, const uint8_t*, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return ERR_NONE;
 }
 
@@ -371,7 +371,7 @@
  * Tell the debugger what we are capable of.
  */
 static JdwpError VM_CapabilitiesNew(JdwpState*, const uint8_t*, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   expandBufAdd1(pReply, false);   /* canWatchFieldModification */
   expandBufAdd1(pReply, false);   /* canWatchFieldAccess */
   expandBufAdd1(pReply, false);   /* canGetBytecodes */
@@ -402,7 +402,7 @@
 }
 
 static JdwpError VM_AllClassesImpl(ExpandBuf* pReply, bool descriptor_and_status, bool generic)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   std::vector<JDWP::RefTypeId> classes;
   Dbg::GetClassList(classes);
 
@@ -433,17 +433,17 @@
 }
 
 static JdwpError VM_AllClasses(JdwpState*, const uint8_t*, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return VM_AllClassesImpl(pReply, true, false);
 }
 
 static JdwpError VM_AllClassesWithGeneric(JdwpState*, const uint8_t*, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return VM_AllClassesImpl(pReply, true, true);
 }
 
 static JdwpError RT_Modifiers(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   return Dbg::GetModifiers(refTypeId, pReply);
 }
@@ -452,7 +452,7 @@
  * Get values from static fields in a reference type.
  */
 static JdwpError RT_GetValues(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   uint32_t field_count = Read4BE(&buf);
   expandBufAdd4BE(pReply, field_count);
@@ -470,7 +470,7 @@
  * Get the name of the source file in which a reference type was declared.
  */
 static JdwpError RT_SourceFile(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   std::string source_file;
   JdwpError status = Dbg::GetSourceFile(refTypeId, source_file);
@@ -485,7 +485,7 @@
  * Return the current status of the reference type.
  */
 static JdwpError RT_Status(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   JDWP::JdwpTypeTag type_tag;
   uint32_t class_status;
@@ -501,7 +501,7 @@
  * Return interfaces implemented directly by this class.
  */
 static JdwpError RT_Interfaces(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   VLOG(jdwp) << StringPrintf("  Req for interfaces in %#llx (%s)", refTypeId, Dbg::GetClassName(refTypeId).c_str());
   return Dbg::OutputDeclaredInterfaces(refTypeId, pReply);
@@ -511,7 +511,7 @@
  * Return the class object corresponding to this type.
  */
 static JdwpError RT_ClassObject(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   ObjectId classObjectId;
   JdwpError status = Dbg::GetClassObject(refTypeId, classObjectId);
@@ -529,14 +529,14 @@
  * JDB seems interested, but DEX files don't currently support this.
  */
 static JdwpError RT_SourceDebugExtension(JdwpState*, const uint8_t*, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   /* referenceTypeId in, string out */
   return ERR_ABSENT_INFORMATION;
 }
 
 static JdwpError RT_Signature(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply,
                               bool with_generic)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
 
   VLOG(jdwp) << StringPrintf("  Req for signature of refTypeId=%#llx", refTypeId);
@@ -554,13 +554,13 @@
 }
 
 static JdwpError RT_Signature(JdwpState* state, const uint8_t* buf, int dataLen, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return RT_Signature(state, buf, dataLen, pReply, false);
 }
 
 static JdwpError RT_SignatureWithGeneric(JdwpState* state, const uint8_t* buf, int dataLen,
                                          ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return RT_Signature(state, buf, dataLen, pReply, true);
 }
 
@@ -569,13 +569,13 @@
  * reference type, or null if it was loaded by the system loader.
  */
 static JdwpError RT_ClassLoader(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   return Dbg::GetClassLoader(refTypeId, pReply);
 }
 
 static std::string Describe(const RefTypeId& refTypeId)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   std::string signature("unknown");
   Dbg::GetSignature(refTypeId, signature);
   return StringPrintf("refTypeId=%#llx (%s)", refTypeId, signature.c_str());
@@ -586,7 +586,7 @@
  * fields declared by a class.
  */
 static JdwpError RT_FieldsWithGeneric(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   VLOG(jdwp) << "  Req for fields in " << Describe(refTypeId);
   return Dbg::OutputDeclaredFields(refTypeId, true, pReply);
@@ -594,7 +594,7 @@
 
 // Obsolete equivalent of FieldsWithGeneric, without the generic type information.
 static JdwpError RT_Fields(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   VLOG(jdwp) << "  Req for fields in " << Describe(refTypeId);
   return Dbg::OutputDeclaredFields(refTypeId, false, pReply);
@@ -605,7 +605,7 @@
  * methods declared by a class.
  */
 static JdwpError RT_MethodsWithGeneric(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   VLOG(jdwp) << "  Req for methods in " << Describe(refTypeId);
   return Dbg::OutputDeclaredMethods(refTypeId, true, pReply);
@@ -613,7 +613,7 @@
 
 // Obsolete equivalent of MethodsWithGeneric, without the generic type information.
 static JdwpError RT_Methods(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   VLOG(jdwp) << "  Req for methods in " << Describe(refTypeId);
   return Dbg::OutputDeclaredMethods(refTypeId, false, pReply);
@@ -623,7 +623,7 @@
  * Return the immediate superclass of a class.
  */
 static JdwpError CT_Superclass(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId class_id = ReadRefTypeId(&buf);
   RefTypeId superClassId;
   JdwpError status = Dbg::GetSuperclass(class_id, superClassId);
@@ -638,7 +638,7 @@
  * Set static class values.
  */
 static JdwpError CT_SetValues(JdwpState* , const uint8_t* buf, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId class_id = ReadRefTypeId(&buf);
   uint32_t values = Read4BE(&buf);
 
@@ -668,7 +668,7 @@
  */
 static JdwpError CT_InvokeMethod(JdwpState* state, const uint8_t* buf, int dataLen,
                                  ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId class_id = ReadRefTypeId(&buf);
   ObjectId thread_id = ReadObjectId(&buf);
   MethodId method_id = ReadMethodId(&buf);
@@ -685,7 +685,7 @@
  */
 static JdwpError CT_NewInstance(JdwpState* state, const uint8_t* buf, int dataLen,
                                 ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId class_id = ReadRefTypeId(&buf);
   ObjectId thread_id = ReadObjectId(&buf);
   MethodId method_id = ReadMethodId(&buf);
@@ -706,7 +706,7 @@
  * Create a new array object of the requested type and length.
  */
 static JdwpError AT_newInstance(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId arrayTypeId = ReadRefTypeId(&buf);
   uint32_t length = Read4BE(&buf);
 
@@ -728,7 +728,7 @@
  * Return line number information for the method, if present.
  */
 static JdwpError M_LineTable(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId refTypeId = ReadRefTypeId(&buf);
   MethodId method_id = ReadMethodId(&buf);
 
@@ -741,7 +741,7 @@
 
 static JdwpError M_VariableTable(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply,
                                  bool generic)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId class_id = ReadRefTypeId(&buf);
   MethodId method_id = ReadMethodId(&buf);
 
@@ -759,13 +759,13 @@
 
 static JdwpError M_VariableTable(JdwpState* state, const uint8_t* buf, int dataLen,
                                  ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return M_VariableTable(state, buf, dataLen, pReply, false);
 }
 
 static JdwpError M_VariableTableWithGeneric(JdwpState* state, const uint8_t* buf, int dataLen,
                                             ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return M_VariableTable(state, buf, dataLen, pReply, true);
 }
 
@@ -777,7 +777,7 @@
  * passed in here.
  */
 static JdwpError OR_ReferenceType(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId object_id = ReadObjectId(&buf);
   VLOG(jdwp) << StringPrintf("  Req for type of object_id=%#llx", object_id);
   return Dbg::GetReferenceType(object_id, pReply);
@@ -787,7 +787,7 @@
  * Get values from the fields of an object.
  */
 static JdwpError OR_GetValues(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId object_id = ReadObjectId(&buf);
   uint32_t field_count = Read4BE(&buf);
 
@@ -810,7 +810,7 @@
  * Set values in the fields of an object.
  */
 static JdwpError OR_SetValues(JdwpState*, const uint8_t* buf, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId object_id = ReadObjectId(&buf);
   uint32_t field_count = Read4BE(&buf);
 
@@ -846,7 +846,7 @@
  */
 static JdwpError OR_InvokeMethod(JdwpState* state, const uint8_t* buf, int dataLen,
                                  ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId object_id = ReadObjectId(&buf);
   ObjectId thread_id = ReadObjectId(&buf);
   RefTypeId class_id = ReadRefTypeId(&buf);
@@ -859,7 +859,7 @@
  * Disable garbage collection of the specified object.
  */
 static JdwpError OR_DisableCollection(JdwpState*, const uint8_t*, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // this is currently a no-op
   return ERR_NONE;
 }
@@ -868,7 +868,7 @@
  * Enable garbage collection of the specified object.
  */
 static JdwpError OR_EnableCollection(JdwpState*, const uint8_t*, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // this is currently a no-op
   return ERR_NONE;
 }
@@ -877,7 +877,7 @@
  * Determine whether an object has been garbage collected.
  */
 static JdwpError OR_IsCollected(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId object_id;
 
   object_id = ReadObjectId(&buf);
@@ -893,7 +893,7 @@
  * Return the string value in a string object.
  */
 static JdwpError SR_Value(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId stringObject = ReadObjectId(&buf);
   std::string str(Dbg::StringToUtf8(stringObject));
 
@@ -908,7 +908,7 @@
  * Return a thread's name.
  */
 static JdwpError TR_Name(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
 
   VLOG(jdwp) << StringPrintf("  Req for name of thread %#llx", thread_id);
@@ -929,7 +929,7 @@
  * resume it; only the JDI is allowed to resume it.
  */
 static JdwpError TR_Suspend(JdwpState*, const uint8_t* buf, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
 
   if (thread_id == Dbg::GetThreadSelfId()) {
@@ -948,7 +948,7 @@
  * Resume the specified thread.
  */
 static JdwpError TR_Resume(JdwpState*, const uint8_t* buf, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
 
   if (thread_id == Dbg::GetThreadSelfId()) {
@@ -964,7 +964,7 @@
  * Return status of specified thread.
  */
 static JdwpError TR_Status(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
 
   VLOG(jdwp) << StringPrintf("  Req for status of thread %#llx", thread_id);
@@ -987,7 +987,7 @@
  * Return the thread group that the specified thread is a member of.
  */
 static JdwpError TR_ThreadGroup(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
   return Dbg::GetThreadGroup(thread_id, pReply);
 }
@@ -999,7 +999,7 @@
  * be THREAD_NOT_SUSPENDED.
  */
 static JdwpError TR_Frames(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
   uint32_t start_frame = Read4BE(&buf);
   uint32_t length = Read4BE(&buf);
@@ -1036,7 +1036,7 @@
  * Returns the #of frames on the specified thread, which must be suspended.
  */
 static JdwpError TR_FrameCount(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
 
   if (!Dbg::ThreadExists(thread_id)) {
@@ -1060,7 +1060,7 @@
  * Get the monitor that the thread is waiting on.
  */
 static JdwpError TR_CurrentContendedMonitor(JdwpState*, const uint8_t* buf, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ReadObjectId(&buf);  // thread_id
 
   // TODO: create an Object to represent the monitor (we're currently
@@ -1076,7 +1076,7 @@
  * its suspend count recently.)
  */
 static JdwpError TR_DebugSuspendCount(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
   return Dbg::GetThreadDebugSuspendCount(thread_id, pReply);
 }
@@ -1087,7 +1087,7 @@
  * The Eclipse debugger recognizes "main" and "system" as special.
  */
 static JdwpError TGR_Name(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_group_id = ReadObjectId(&buf);
   VLOG(jdwp) << StringPrintf("  Req for name of thread_group_id=%#llx", thread_group_id);
 
@@ -1101,7 +1101,7 @@
  * thread group.
  */
 static JdwpError TGR_Parent(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_group_id = ReadObjectId(&buf);
 
   ObjectId parentGroup = Dbg::GetThreadGroupParent(thread_group_id);
@@ -1115,7 +1115,7 @@
  * specified thread group.
  */
 static JdwpError TGR_Children(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_group_id = ReadObjectId(&buf);
   VLOG(jdwp) << StringPrintf("  Req for threads in thread_group_id=%#llx", thread_group_id);
 
@@ -1140,7 +1140,7 @@
  * Return the #of components in the array.
  */
 static JdwpError AR_Length(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId arrayId = ReadObjectId(&buf);
   VLOG(jdwp) << StringPrintf("  Req for length of array %#llx", arrayId);
 
@@ -1160,7 +1160,7 @@
  * Return the values from an array.
  */
 static JdwpError AR_GetValues(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId arrayId = ReadObjectId(&buf);
   uint32_t firstIndex = Read4BE(&buf);
   uint32_t length = Read4BE(&buf);
@@ -1173,7 +1173,7 @@
  * Set values in an array.
  */
 static JdwpError AR_SetValues(JdwpState*, const uint8_t* buf, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId arrayId = ReadObjectId(&buf);
   uint32_t firstIndex = Read4BE(&buf);
   uint32_t values = Read4BE(&buf);
@@ -1185,7 +1185,7 @@
 }
 
 static JdwpError CLR_VisibleClasses(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ReadObjectId(&buf);  // classLoaderObject
   // TODO: we should only return classes which have the given class loader as a defining or
   // initiating loader. The former would be easy; the latter is hard, because we don't have
@@ -1199,7 +1199,7 @@
  * Reply with a requestID.
  */
 static JdwpError ER_Set(JdwpState* state, const uint8_t* buf, int dataLen, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   const uint8_t* origBuf = buf;
 
   uint8_t eventKind = Read1(&buf);
@@ -1369,7 +1369,7 @@
  * and does not return an error.
  */
 static JdwpError ER_Clear(JdwpState* state, const uint8_t* buf, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   uint8_t eventKind;
   eventKind = Read1(&buf);
   uint32_t requestId = Read4BE(&buf);
@@ -1385,7 +1385,7 @@
  * Return the values of arguments and local variables.
  */
 static JdwpError SF_GetValues(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
   FrameId frame_id = ReadFrameId(&buf);
   uint32_t slots = Read4BE(&buf);
@@ -1411,7 +1411,7 @@
  * Set the values of arguments and local variables.
  */
 static JdwpError SF_SetValues(JdwpState*, const uint8_t* buf, int, ExpandBuf*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
   FrameId frame_id = ReadFrameId(&buf);
   uint32_t slots = Read4BE(&buf);
@@ -1435,7 +1435,7 @@
  * Returns the value of "this" for the specified frame.
  */
 static JdwpError SF_ThisObject(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ObjectId thread_id = ReadObjectId(&buf);
   FrameId frame_id = ReadFrameId(&buf);
 
@@ -1467,7 +1467,7 @@
  * that, or I have no idea what this is for.)
  */
 static JdwpError COR_ReflectedType(JdwpState*, const uint8_t* buf, int, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   RefTypeId classObjectId = ReadRefTypeId(&buf);
   VLOG(jdwp) << StringPrintf("  Req for refTypeId for class=%#llx (%s)", classObjectId,
                              Dbg::GetClassName(classObjectId).c_str());
@@ -1478,7 +1478,7 @@
  * Handle a DDM packet with a single chunk in it.
  */
 static JdwpError DDM_Chunk(JdwpState* state, const uint8_t* buf, int dataLen, ExpandBuf* pReply)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   uint8_t* replyBuf = NULL;
   int replyLen = -1;
 
diff --git a/src/jdwp/jdwp_main.cc b/src/jdwp/jdwp_main.cc
index 4b442db..4fec005 100644
--- a/src/jdwp/jdwp_main.cc
+++ b/src/jdwp/jdwp_main.cc
@@ -118,7 +118,7 @@
  * the thread is accepting network connections.
  */
 JdwpState* JdwpState::Create(const JdwpOptions* options) {
-  GlobalSynchronization::mutator_lock_->AssertNotHeld();
+  Locks::mutator_lock_->AssertNotHeld();
   UniquePtr<JdwpState> state(new JdwpState(options));
   switch (options->transport) {
   case kJdwpTransportSocket:
@@ -301,7 +301,7 @@
 
   /* set the thread state to kWaitingInMainDebuggerLoop so GCs don't wait for us */
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_EQ(thread_->GetState(), kNative);
     thread_->SetState(kWaitingInMainDebuggerLoop);
   }
@@ -346,7 +346,7 @@
     while (!Dbg::IsDisposed()) {
       {
         // sanity check -- shouldn't happen?
-        MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+        MutexLock mu(*Locks::thread_suspend_count_lock_);
         CHECK_EQ(thread_->GetState(), kWaitingInMainDebuggerLoop);
       }
 
@@ -401,7 +401,7 @@
 
   /* back to native, for thread shutdown */
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_EQ(thread_->GetState(), kWaitingInMainDebuggerLoop);
     thread_->SetState(kNative);
   }
diff --git a/src/jni_compiler_test.cc b/src/jni_compiler_test.cc
index 72b5848..e0320b3 100644
--- a/src/jni_compiler_test.cc
+++ b/src/jni_compiler_test.cc
@@ -116,9 +116,9 @@
   // 1 = thisObj
   EXPECT_EQ(1U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
-    GlobalSynchronization::mutator_lock_->AssertNotHeld();
+    Locks::mutator_lock_->AssertNotHeld();
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
   EXPECT_TRUE(thisObj != NULL);
@@ -170,7 +170,7 @@
   // 1 = thisObj
   EXPECT_EQ(1U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
@@ -198,7 +198,7 @@
   // 1 = thisObj
   EXPECT_EQ(1U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
@@ -227,7 +227,7 @@
   // 1 = thisObj
   EXPECT_EQ(1U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
@@ -257,7 +257,7 @@
   // 1 = thisObj
   EXPECT_EQ(1U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
@@ -288,7 +288,7 @@
   // 1 = thisObj
   EXPECT_EQ(1U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
@@ -316,7 +316,7 @@
   // 3 = this + y + z
   EXPECT_EQ(3U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
@@ -369,7 +369,7 @@
   // 1 = klass
   EXPECT_EQ(1U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
@@ -394,7 +394,7 @@
   // 1 = klass
   EXPECT_EQ(1U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
@@ -425,7 +425,7 @@
   // 3 = klass + y + z
   EXPECT_EQ(3U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
@@ -479,7 +479,7 @@
   // 3 = klass + y + z
   EXPECT_EQ(3U, Thread::Current()->NumStackReferences());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     EXPECT_EQ(kNative, Thread::Current()->GetState());
   }
   EXPECT_EQ(Thread::Current()->GetJniEnv(), env);
diff --git a/src/jni_internal.cc b/src/jni_internal.cc
index ab2286f..6dc1a73 100644
--- a/src/jni_internal.cc
+++ b/src/jni_internal.cc
@@ -93,7 +93,7 @@
 
 class ArgArray {
  public:
-  explicit ArgArray(Method* method) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  explicit ArgArray(Method* method) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     MethodHelper mh(method);
     shorty_ = mh.GetShorty();
     shorty_len_ = mh.GetShortyLength();
@@ -110,7 +110,7 @@
   }
 
   void BuildArgArray(const ScopedObjectAccess& soa, va_list ap)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     for (size_t i = 1, offset = 0; i < shorty_len_; ++i, ++offset) {
       switch (shorty_[i]) {
         case 'Z':
@@ -145,7 +145,7 @@
   }
 
   void BuildArgArray(const ScopedObjectAccess& soa, jvalue* args)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     for (size_t i = 1, offset = 0; i < shorty_len_; ++i, ++offset) {
       switch (shorty_[i]) {
         case 'Z':
@@ -189,7 +189,7 @@
 };
 
 static jweak AddWeakGlobalReference(ScopedObjectAccess& soa, Object* obj)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (obj == NULL) {
     return NULL;
   }
@@ -201,7 +201,7 @@
 }
 
 static void CheckMethodArguments(Method* m, JValue* args)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   MethodHelper mh(m);
   ObjectArray<Class>* parameter_types = mh.GetParameterTypes();
   CHECK(parameter_types != NULL);
@@ -227,7 +227,7 @@
 
 static JValue InvokeWithArgArray(const ScopedObjectAccess& soa, Object* receiver,
                                  Method* method, JValue* args)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (UNLIKELY(soa.Env()->check_jni)) {
     CheckMethodArguments(method, args);
   }
@@ -238,7 +238,7 @@
 
 static JValue InvokeWithVarArgs(const ScopedObjectAccess& soa, jobject obj,
                                 jmethodID mid, va_list args)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Object* receiver = soa.Decode<Object*>(obj);
   Method* method = soa.DecodeMethod(mid);
   ArgArray arg_array(method);
@@ -247,13 +247,13 @@
 }
 
 static Method* FindVirtualMethod(Object* receiver, Method* method)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return receiver->GetClass()->FindVirtualMethodForVirtualOrInterface(method);
 }
 
 static JValue InvokeVirtualOrInterfaceWithJValues(const ScopedObjectAccess& soa,
                                                   jobject obj, jmethodID mid, jvalue* args)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Object* receiver = soa.Decode<Object*>(obj);
   Method* method = FindVirtualMethod(receiver, soa.DecodeMethod(mid));
   ArgArray arg_array(method);
@@ -263,7 +263,7 @@
 
 static JValue InvokeVirtualOrInterfaceWithVarArgs(const ScopedObjectAccess& soa,
                                                   jobject obj, jmethodID mid, va_list args)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Object* receiver = soa.Decode<Object*>(obj);
   Method* method = FindVirtualMethod(receiver, soa.DecodeMethod(mid));
   ArgArray arg_array(method);
@@ -297,14 +297,14 @@
 
 static void ThrowNoSuchMethodError(ScopedObjectAccess& soa, Class* c,
                                    const char* name, const char* sig, const char* kind)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   soa.Self()->ThrowNewExceptionF("Ljava/lang/NoSuchMethodError;",
       "no %s method \"%s.%s%s\"", kind, ClassHelper(c).GetDescriptor(), name, sig);
 }
 
 static jmethodID FindMethodID(ScopedObjectAccess& soa, jclass jni_class,
                               const char* name, const char* sig, bool is_static)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Class* c = soa.Decode<Class*>(jni_class);
   if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(c, true, true)) {
     return NULL;
@@ -331,7 +331,7 @@
 }
 
 static ClassLoader* GetClassLoader(Thread* self)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Method* method = self->GetCurrentMethod();
   if (method == NULL || PrettyMethod(method, false) == "java.lang.Runtime.nativeLoad") {
     return self->GetClassLoaderOverride();
@@ -341,7 +341,7 @@
 
 static jfieldID FindFieldID(const ScopedObjectAccess& soa, jclass jni_class, const char* name,
                             const char* sig, bool is_static)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Class* c = soa.Decode<Class*>(jni_class);
   if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(c, true, true)) {
     return NULL;
@@ -380,14 +380,14 @@
 }
 
 static void PinPrimitiveArray(const ScopedObjectAccess& soa, const Array* array)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   JavaVMExt* vm = soa.Vm();
   MutexLock mu(vm->pins_lock);
   vm->pin_table.Add(array);
 }
 
 static void UnpinPrimitiveArray(const ScopedObjectAccess& soa, const Array* array)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   JavaVMExt* vm = soa.Vm();
   MutexLock mu(vm->pins_lock);
   vm->pin_table.Remove(array);
@@ -395,7 +395,7 @@
 
 static void ThrowAIOOBE(ScopedObjectAccess& soa, Array* array, jsize start,
                         jsize length, const char* identifier)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   std::string type(PrettyTypeOf(array));
   soa.Self()->ThrowNewExceptionF("Ljava/lang/ArrayIndexOutOfBoundsException;",
       "%s offset=%d length=%d %s.length=%d",
@@ -404,13 +404,13 @@
 
 static void ThrowSIOOBE(ScopedObjectAccess& soa, jsize start, jsize length,
                         jsize array_length)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   soa.Self()->ThrowNewExceptionF("Ljava/lang/StringIndexOutOfBoundsException;",
       "offset=%d length=%d string.length()=%d", start, length, array_length);
 }
 
 int ThrowNewException(JNIEnv* env, jclass exception_class, const char* msg, jobject cause)
-    LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
+    LOCKS_EXCLUDED(Locks::mutator_lock_) {
   ScopedObjectAccess soa(env);
 
   // Turn the const char* into a java.lang.String.
@@ -512,7 +512,7 @@
    */
   bool CheckOnLoadResult()
       LOCKS_EXCLUDED(jni_on_load_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Thread* self = Thread::Current();
     self->TransitionFromRunnableToSuspended(kWaitingForJniOnLoad);
     bool okay;
@@ -615,7 +615,7 @@
 
   // See section 11.3 "Linking Native Methods" of the JNI spec.
   void* FindNativeMethod(const Method* m, std::string& detail)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     std::string jni_short_name(JniShortName(m));
     std::string jni_long_name(JniLongName(m));
     const ClassLoader* declaring_class_loader = m->GetDeclaringClass()->GetClassLoader();
@@ -660,7 +660,7 @@
 
 JValue InvokeWithJValues(const ScopedObjectAccess& soa, Object* receiver, Method* m,
                          JValue* args)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return InvokeWithArgArray(soa, receiver, m, args);
 }
 
@@ -2286,7 +2286,7 @@
  private:
   static jint EnsureLocalCapacity(const ScopedObjectAccess& soa, jint desired_capacity,
                                   const char* caller)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     // TODO: we should try to expand the table if necessary.
     if (desired_capacity < 1 || desired_capacity > static_cast<jint>(kLocalsMax)) {
       LOG(ERROR) << "Invalid capacity given to " << caller << ": " << desired_capacity;
@@ -2303,7 +2303,7 @@
 
   template<typename JniT, typename ArtT>
   static JniT NewPrimitiveArray(const ScopedObjectAccess& soa, jsize length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK_GE(length, 0); // TODO: ReportJniError
     ArtT* result = ArtT::Alloc(length);
     return soa.AddLocalReference<JniT>(result);
@@ -2312,7 +2312,7 @@
   template <typename ArrayT, typename CArrayT, typename ArtArrayT>
   static CArrayT GetPrimitiveArray(ScopedObjectAccess& soa, ArrayT java_array,
                                    jboolean* is_copy)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ArtArrayT* array = soa.Decode<ArtArrayT*>(java_array);
     PinPrimitiveArray(soa, array);
     if (is_copy != NULL) {
@@ -2324,7 +2324,7 @@
   template <typename ArrayT>
   static void ReleasePrimitiveArray(ScopedObjectAccess& soa, ArrayT java_array,
                                     jint mode)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (mode != JNI_COMMIT) {
       Array* array = soa.Decode<Array*>(java_array);
       UnpinPrimitiveArray(soa, array);
@@ -2334,7 +2334,7 @@
   template <typename JavaArrayT, typename JavaT, typename ArrayT>
   static void GetPrimitiveArrayRegion(ScopedObjectAccess& soa, JavaArrayT java_array,
                                       jsize start, jsize length, JavaT* buf)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ArrayT* array = soa.Decode<ArrayT*>(java_array);
     if (start < 0 || length < 0 || start + length > array->GetLength()) {
       ThrowAIOOBE(soa, array, start, length, "src");
@@ -2347,7 +2347,7 @@
   template <typename JavaArrayT, typename JavaT, typename ArrayT>
   static void SetPrimitiveArrayRegion(ScopedObjectAccess& soa, JavaArrayT java_array,
                                       jsize start, jsize length, const JavaT* buf)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ArrayT* array = soa.Decode<ArrayT*>(java_array);
     if (start < 0 || length < 0 || start + length > array->GetLength()) {
       ThrowAIOOBE(soa, array, start, length, "dst");
diff --git a/src/jni_internal.h b/src/jni_internal.h
index fad06e1..6833c2a 100644
--- a/src/jni_internal.h
+++ b/src/jni_internal.h
@@ -54,9 +54,9 @@
 
 size_t NumArgArrayBytes(const char* shorty, uint32_t shorty_len);
 JValue InvokeWithJValues(const ScopedObjectAccess&, jobject obj, jmethodID mid, jvalue* args)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 JValue InvokeWithJValues(const ScopedObjectAccess&, Object* receiver, Method* m, JValue* args)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 int ThrowNewException(JNIEnv* env, jclass exception_class, const char* msg, jobject cause);
 
@@ -71,19 +71,19 @@
    * human-readable description of the error.
    */
   bool LoadNativeLibrary(const std::string& path, ClassLoader* class_loader, std::string& detail)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /**
    * Returns a pointer to the code for the native method 'm', found
    * using dlsym(3) on every native library that's been loaded so far.
    */
   void* FindCodeForNativeMethod(Method* m)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void DumpForSigQuit(std::ostream& os);
 
   void DumpReferenceTables(std::ostream& os)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void SetCheckJniEnabled(bool enabled);
 
@@ -129,7 +129,7 @@
   ~JNIEnvExt();
 
   void DumpReferenceTables(std::ostream& os)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void SetCheckJniEnabled(bool enabled);
 
diff --git a/src/jni_internal_test.cc b/src/jni_internal_test.cc
index 64461b0..5db258d 100644
--- a/src/jni_internal_test.cc
+++ b/src/jni_internal_test.cc
@@ -70,7 +70,7 @@
 
   Method::InvokeStub* DoCompile(Method*& method, Object*& receiver, bool is_static,
                                 const char* method_name, const char* method_signature)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const char* class_name = is_static ? "StaticLeafMethods" : "NonStaticLeafMethods";
     jobject jclass_loader(LoadDex(class_name));
     SirtRef<ClassLoader> class_loader(ScopedObjectAccessUnchecked(Thread::Current()).Decode<ClassLoader*>(jclass_loader));
@@ -97,7 +97,7 @@
     return stub;
   }
 
-  void InvokeNopMethod(bool is_static) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void InvokeNopMethod(bool is_static) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "nop", "()V");
@@ -105,7 +105,7 @@
   }
 
   void InvokeIdentityByteMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "identity", "(B)B");
@@ -135,7 +135,7 @@
   }
 
   void InvokeIdentityIntMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "identity", "(I)I");
@@ -165,7 +165,7 @@
   }
 
   void InvokeIdentityDoubleMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "identity", "(D)D");
@@ -195,7 +195,7 @@
   }
 
   void InvokeSumIntIntMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "sum", "(II)I");
@@ -234,7 +234,7 @@
   }
 
   void InvokeSumIntIntIntMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "sum", "(III)I");
@@ -278,7 +278,7 @@
   }
 
   void InvokeSumIntIntIntIntMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "sum", "(IIII)I");
@@ -327,7 +327,7 @@
   }
 
   void InvokeSumIntIntIntIntIntMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "sum", "(IIIII)I");
@@ -381,7 +381,7 @@
   }
 
   void InvokeSumDoubleDoubleMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "sum", "(DD)D");
@@ -421,7 +421,7 @@
   }
 
   void InvokeSumDoubleDoubleDoubleMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "sum", "(DDD)D");
@@ -452,7 +452,7 @@
   }
 
   void InvokeSumDoubleDoubleDoubleDoubleMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "sum", "(DDDD)D");
@@ -486,7 +486,7 @@
   }
 
   void InvokeSumDoubleDoubleDoubleDoubleDoubleMethod(bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method;
     Object* receiver;
     Method::InvokeStub* stub = DoCompile(method, receiver, is_static, "sum", "(DDDDD)D");
diff --git a/src/logging.cc b/src/logging.cc
index 712c02b..a0c07cf 100644
--- a/src/logging.cc
+++ b/src/logging.cc
@@ -51,7 +51,7 @@
 // This can be used to reveal or conceal logs with specific tags.
 void InitLogging(char* argv[]) {
   // TODO: Move this to a more obvious InitART...
-  GlobalSynchronization::Init();
+  Locks::Init();
 
   // Stash the command line for later use. We can use /proc/self/cmdline on Linux to recover this,
   // but we don't have that luxury on the Mac, and there are a couple of argv[0] variants that are
@@ -104,7 +104,7 @@
 
   // Do the actual logging with the lock held.
   {
-    MutexLock mu(*GlobalSynchronization::logging_lock_);
+    MutexLock mu(*Locks::logging_lock_);
     if (msg.find('\n') == std::string::npos) {
       LogLine(msg.c_str());
     } else {
diff --git a/src/logging.h b/src/logging.h
index ce86a72..75782d5 100644
--- a/src/logging.h
+++ b/src/logging.h
@@ -187,7 +187,7 @@
 class LogMessage {
  public:
   LogMessage(const char* file, int line, LogSeverity severity, int error);
-  ~LogMessage() LOCKS_EXCLUDED(GlobalSynchronization::logging_lock_);
+  ~LogMessage() LOCKS_EXCLUDED(Locks::logging_lock_);
   std::ostream& stream();
 
  private:
@@ -253,10 +253,10 @@
 class MutatorLockedDumpable {
  public:
   explicit MutatorLockedDumpable(T& value)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) : value_(value) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) : value_(value) {
   }
 
-  void Dump(std::ostream& os) const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void Dump(std::ostream& os) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     value_.Dump(os);
   }
 
@@ -271,7 +271,7 @@
 
 template<typename T>
 std::ostream& operator<<(std::ostream& os, const MutatorLockedDumpable<T>& rhs)
-// TODO: should be SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) however annotalysis
+// TODO: should be SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) however annotalysis
 //       currently fails for this.
     NO_THREAD_SAFETY_ANALYSIS {
   rhs.Dump(os);
diff --git a/src/mark_sweep.cc b/src/mark_sweep.cc
index 0b09f90..c21c19c 100644
--- a/src/mark_sweep.cc
+++ b/src/mark_sweep.cc
@@ -160,8 +160,8 @@
   }
 
   void operator ()(const Object* obj, const Object* ref, MemberOffset offset, bool is_static) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_,
+                            Locks::mutator_lock_) {
     mark_sweep_->CheckReference(obj, ref, offset, is_static);
   }
 
@@ -195,8 +195,8 @@
   }
 
   void operator ()(const Object* root) const
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(root != NULL);
     mark_sweep_->ScanObject(root);
   }
@@ -245,8 +245,8 @@
   }
 
   void operator ()(const Object* obj) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_,
+                            Locks::mutator_lock_) {
     DCHECK(obj != NULL);
     mark_sweep_->CheckObject(obj);
   }
@@ -280,8 +280,8 @@
   }
 
   void operator ()(const Object* obj) const
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     mark_sweep_->ScanObject(obj);
   }
 
@@ -415,7 +415,7 @@
 };
 
 void MarkSweep::SweepCallback(size_t num_ptrs, Object** ptrs, void* arg) {
-  GlobalSynchronization::heap_bitmap_lock_->AssertExclusiveHeld();
+  Locks::heap_bitmap_lock_->AssertExclusiveHeld();
 
   size_t freed_objects = num_ptrs;
   size_t freed_bytes = 0;
@@ -449,7 +449,7 @@
 }
 
 void MarkSweep::ZygoteSweepCallback(size_t num_ptrs, Object** ptrs, void* arg) {
-  GlobalSynchronization::heap_bitmap_lock_->AssertExclusiveHeld();
+  Locks::heap_bitmap_lock_->AssertExclusiveHeld();
 
   SweepCallbackContext* context = static_cast<SweepCallbackContext*>(arg);
   Heap* heap = context->mark_sweep->GetHeap();
diff --git a/src/mark_sweep.h b/src/mark_sweep.h
index 2333bdb..d1e3481 100644
--- a/src/mark_sweep.h
+++ b/src/mark_sweep.h
@@ -46,14 +46,14 @@
 
   // Marks the root set at the start of a garbage collection.
   void MarkRoots()
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Marks the roots in the image space on dirty cards.
-  void ScanDirtyImageRoots() EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+  void ScanDirtyImageRoots() EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Verify that image roots point to only marked objects within the alloc space.
-  void VerifyImageRoots() EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+  void VerifyImageRoots() EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   bool IsMarkStackEmpty() const {
     return mark_stack_->IsEmpty();
@@ -61,8 +61,8 @@
 
   // Builds a mark stack and recursively mark until it empties.
   void RecursiveMark(bool partial, TimingLogger& timings)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Copies mark bits from live bitmap of ZygoteSpace to mark bitmap for partial GCs.
   void CopyMarkBits(Space* space);
@@ -70,27 +70,27 @@
   // Builds a mark stack with objects on dirty cards and recursively mark
   // until it empties.
   void RecursiveMarkDirtyObjects(bool update_finger)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Recursive mark objects on specified cards. Updates finger.
   void RecursiveMarkCards(CardTable* card_table, const std::vector<byte*>& cards,
                           TimingLogger& timings)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);;
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);;
 
   // Remarks the root set after completing the concurrent mark.
   void ReMarkRoots()
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Heap* GetHeap() {
     return heap_;
   }
 
   void ProcessReferences(bool clear_soft_references)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ProcessReferences(&soft_reference_list_, clear_soft_references,
                       &weak_reference_list_,
                       &finalizer_reference_list_,
@@ -99,11 +99,11 @@
 
   // Sweeps unmarked objects to complete the garbage collection.
   void Sweep(bool partial, bool swap_bitmaps)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Sweep only pointers within an array. WARNING: Trashes objects.
   void SweepArray(TimingLogger& logger, MarkStack* allocation_stack_, bool swap_bitmaps)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   Object* GetClearedReferences() {
     return cleared_reference_list_;
@@ -111,13 +111,13 @@
 
   // Proxy for external access to ScanObject.
   void ScanRoot(const Object* obj)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Blackens an object.
   void ScanObject(const Object* obj)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void SetFinger(Object* new_finger) {
     finger_ = new_finger;
@@ -140,12 +140,12 @@
   }
 
   void SweepSystemWeaks(bool swap_bitmaps)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   template <typename Visitor>
   static void VisitObjectReferences(const Object* obj, const Visitor& visitor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_,
+                            Locks::mutator_lock_) {
     DCHECK(obj != NULL);
     DCHECK(obj->GetClass() != NULL);
     if (obj->IsClass()) {
@@ -160,7 +160,7 @@
  private:
   // Returns true if the object has its bit set in the mark bitmap.
   bool IsMarked(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
     DCHECK(current_mark_bitmap_ != NULL);
     if (current_mark_bitmap_->HasAddress(object)) {
       return current_mark_bitmap_->Test(object);
@@ -169,61 +169,58 @@
   }
 
   static bool IsMarkedCallback(const Object* object, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   static bool IsLiveCallback(const Object* object, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   static void MarkObjectVisitor(const Object* root, void* arg)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   static void ReMarkObjectVisitor(const Object* root, void* arg)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   static void VerifyImageRootVisitor(Object* root, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_,
+                            Locks::mutator_lock_);
 
   static void ScanDirtyCardCallback(Object* obj, void* arg)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Marks an object.
   void MarkObject(const Object* obj)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Yuck.
   void MarkObject0(const Object* obj, bool check_finger)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   static void ScanBitmapCallback(Object* obj, void* finger, void* arg)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void SweepCallback(size_t num_ptrs, Object** ptrs, void* arg)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Special sweep for zygote that just marks objects / dirties cards.
   static void ZygoteSweepCallback(size_t num_ptrs, Object** ptrs, void* arg)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   void CheckReference(const Object* obj, const Object* ref, MemberOffset offset, bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_);
 
   void CheckObject(const Object* obj)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_);
 
   // Grays references in instance fields.
   void ScanInstanceFields(const Object* obj)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   template <typename Visitor>
   static void VisitInstanceFieldsReferences(const Object* obj, const Visitor& visitor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_) {
     DCHECK(obj != NULL);
     Class* klass = obj->GetClass();
     DCHECK(klass != NULL);
@@ -232,41 +229,39 @@
 
   // Blackens a class object.
   void ScanClass(const Object* obj)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 
   template <typename Visitor>
   static void VisitClassReferences(const Object* obj, const Visitor& visitor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_) {
     VisitInstanceFieldsReferences(obj, visitor);
     VisitStaticFieldsReferences(obj->AsClass(), visitor);
   }
 
   // Grays references in static fields.
   void ScanStaticFields(const Class* klass)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   template <typename Visitor>
   static void VisitStaticFieldsReferences(const Class* klass, const Visitor& visitor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_) {
     DCHECK(klass != NULL);
     VisitFieldsReferences(klass, klass->GetReferenceStaticOffsets(), true, visitor);
   }
 
   // Used by ScanInstanceFields and ScanStaticFields
   void ScanFields(const Object* obj, uint32_t ref_offsets, bool is_static)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   template <typename Visitor>
   static void VisitFieldsReferences(const Object* obj, uint32_t ref_offsets, bool is_static,
                              const Visitor& visitor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_,
+                            Locks::mutator_lock_) {
     if (ref_offsets != CLASS_WALK_SUPER) {
       // Found a reference offset bitmap.  Mark the specified offsets.
       while (ref_offsets != 0) {
@@ -301,13 +296,12 @@
 
   // Grays references in an array.
   void ScanArray(const Object* obj)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   template <typename Visitor>
   static void VisitArrayReferences(const Object* obj, const Visitor& visitor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_) {
     visitor(obj, obj->GetClass(), Object::ClassOffset(), false);
     if (obj->IsObjectArray()) {
       const ObjectArray<Object>* array = obj->AsObjectArray<Object>();
@@ -320,49 +314,48 @@
   }
 
   void ScanOther(const Object* obj)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   template <typename Visitor>
   static void VisitOtherReferences(const Object* obj, const Visitor& visitor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_) {
     return VisitInstanceFieldsReferences(obj, visitor);
   }
 
   // Blackens objects grayed during a garbage collection.
   void ScanGrayObjects(bool update_finger)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Schedules an unmarked object for reference processing.
   void DelayReferenceReferent(Object* reference)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Recursively blackens objects on the mark stack.
   void ProcessMarkStack()
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void EnqueueFinalizerReferences(Object** ref)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void PreserveSomeSoftReferences(Object** ref)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void ClearWhiteReferences(Object** list)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   void ProcessReferences(Object** soft_references, bool clear_soft_references,
                          Object** weak_references,
                          Object** finalizer_references,
                          Object** phantom_references)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void SweepJniWeakGlobals(bool swap_bitmaps)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Current space, we check this space first to avoid searching for the appropriate space for an object.
   SpaceBitmap* current_mark_bitmap_;
diff --git a/src/mod_union_table.cc b/src/mod_union_table.cc
index eb8c598..d62128d 100644
--- a/src/mod_union_table.cc
+++ b/src/mod_union_table.cc
@@ -57,8 +57,8 @@
   }
 
   void operator ()(Object* obj) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_,
+                            Locks::mutator_lock_) {
     DCHECK(obj != NULL);
     // We don't have an early exit since we use the visitor pattern, an early
     // exit should significantly speed this up.
@@ -155,8 +155,8 @@
   }
 
   void operator ()(const Object* root) const
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(root != NULL);
     mark_sweep_->ScanRoot(root);
   }
@@ -226,8 +226,8 @@
   }
 
   void operator ()(Object* obj) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_,
+                            Locks::mutator_lock_) {
     DCHECK(obj != NULL);
     // We don't have an early exit since we use the visitor pattern, an early
     // exit should significantly speed this up.
@@ -254,8 +254,7 @@
   // Extra parameters are required since we use this same visitor signature for checking objects.
   void operator ()(const Object* obj, const Object* ref, const MemberOffset& /* offset */,
                      bool /* is_static */) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_) {
     Heap* heap = mod_union_table_->GetMarkSweep()->GetHeap();
     if (mod_union_table_->AddReference(obj, ref) && references_.find(ref) == references_.end()) {
       Space* from_space = heap->FindSpaceFromObject(obj);
@@ -287,8 +286,7 @@
   }
 
   void operator ()(Object* obj) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_,
-                            GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_) {
     DCHECK(obj != NULL);
     MarkSweep* mark_sweep = mod_union_table_->GetMarkSweep();
     CheckReferenceVisitor visitor(mod_union_table_, references_);
diff --git a/src/mod_union_table.h b/src/mod_union_table.h
index df2023f..17ca240 100644
--- a/src/mod_union_table.h
+++ b/src/mod_union_table.h
@@ -54,7 +54,7 @@
   // for said cards. Exclusive lock is required since verify sometimes uses
   // SpaceBitmap::VisitMarkedRange and VisitMarkedRange can't know if the callback will modify the
   // bitmap or not.
-  virtual void Verify() EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) = 0;
+  virtual void Verify() EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) = 0;
 
   // Should probably clean this up later.
   void Init(MarkSweep* mark_sweep) {
@@ -86,11 +86,11 @@
 
   // Update table based on cleared cards.
   void Update()
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Mark all references to the alloc space(s).
-  void MarkReferences() EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+  void MarkReferences() EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
  protected:
   // Cleared card array, used to update the mod-union table.
@@ -115,15 +115,15 @@
 
   // Update table based on cleared cards.
   void Update()
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Mark all references to the alloc space(s).
-  void MarkReferences() EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+  void MarkReferences() EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Exclusive lock is required since verify uses SpaceBitmap::VisitMarkedRange and
   // VisitMarkedRange can't know if the callback will modify the bitmap or not.
-  void Verify() EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+  void Verify() EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   // Function that tells whether or not to add a reference to the table.
   virtual bool AddReference(const Object* obj, const Object* ref) = 0;
@@ -152,8 +152,8 @@
 
   // Mark all references to the alloc space(s).
   void MarkReferences()
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Nothing to verify.
   void Verify() {}
diff --git a/src/monitor.cc b/src/monitor.cc
index 0e6735d..6b7fbf1 100644
--- a/src/monitor.cc
+++ b/src/monitor.cc
@@ -252,7 +252,7 @@
                                               __attribute__((format(printf, 1, 2)));
 
 static void ThrowIllegalMonitorStateExceptionF(const char* fmt, ...)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   va_list args;
   va_start(args, fmt);
   Thread::Current()->ThrowNewExceptionV("Ljava/lang/IllegalMonitorStateException;", fmt, args);
@@ -284,7 +284,7 @@
   {
     // TODO: isn't this too late to prevent threads from disappearing?
     // Acquire thread list lock so threads won't disappear from under us.
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
     // Re-read owner now that we hold lock.
     current_owner = (monitor != NULL) ? monitor->owner_ : NULL;
     // Get short descriptions of the threads involved.
@@ -366,7 +366,7 @@
 
 // Converts the given waiting time (relative to "now") into an absolute time in 'ts'.
 static void ToAbsoluteTime(int64_t ms, int32_t ns, timespec* ts)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   int64_t endSec;
 
 #ifdef HAVE_TIMEDWAIT_MONOTONIC
@@ -873,7 +873,7 @@
 void Monitor::DescribeWait(std::ostream& os, const Thread* thread) {
   ThreadState state;
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     state = thread->GetState();
   }
 
@@ -913,7 +913,7 @@
 }
 
 static void DumpLockedObject(std::ostream& os, Object* o)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   os << "  - locked <" << o << "> (a " << PrettyTypeOf(o) << ")\n";
 }
 
diff --git a/src/monitor.h b/src/monitor.h
index b506b39..de70803 100644
--- a/src/monitor.h
+++ b/src/monitor.h
@@ -73,43 +73,43 @@
 
   static void MonitorEnter(Thread* thread, Object* obj)
       EXCLUSIVE_LOCK_FUNCTION(monitor_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static bool MonitorExit(Thread* thread, Object* obj)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       UNLOCK_FUNCTION(monitor_lock_);
 
   static void Notify(Thread* self, Object* obj)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void NotifyAll(Thread* self, Object* obj)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void Wait(Thread* self, Object* obj, int64_t ms, int32_t ns, bool interruptShouldThrow)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void DescribeWait(std::ostream& os, const Thread* thread)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void DescribeLocks(std::ostream& os, StackVisitor* stack_visitor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Object* GetObject();
 
  private:
   explicit Monitor(Thread* owner, Object* obj)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void AppendToWaitSet(Thread* thread) EXCLUSIVE_LOCKS_REQUIRED(monitor_lock_);
   void RemoveFromWaitSet(Thread* thread) EXCLUSIVE_LOCKS_REQUIRED(monitor_lock_);
 
   static void Inflate(Thread* self, Object* obj)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void LogContentionEvent(Thread* self, uint32_t wait_ms, uint32_t sample_percent,
                           const char* owner_filename, uint32_t owner_line_number)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void FailedUnlock(Object* obj, Thread* expected_owner, Thread* found_owner, Monitor* mon)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void Lock(Thread* self) EXCLUSIVE_LOCK_FUNCTION(monitor_lock_);
   bool Unlock(Thread* thread, bool for_wait) UNLOCK_FUNCTION(monitor_lock_);
@@ -117,24 +117,24 @@
   void Notify(Thread* self) NO_THREAD_SAFETY_ANALYSIS;
   void NotifyWithLock()
       EXCLUSIVE_LOCKS_REQUIRED(monitor_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void NotifyAll(Thread* self) NO_THREAD_SAFETY_ANALYSIS;
   void NotifyAllWithLock()
       EXCLUSIVE_LOCKS_REQUIRED(monitor_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 
   void Wait(Thread* self, int64_t msec, int32_t nsec, bool interruptShouldThrow)
       NO_THREAD_SAFETY_ANALYSIS;
   void WaitWithLock(Thread* self, int64_t ms, int32_t ns, bool interruptShouldThrow)
       EXCLUSIVE_LOCKS_REQUIRED(monitor_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Translates the provided method and pc into its declaring class' source file and line number.
   void TranslateLocation(const Method* method, uint32_t pc,
                          const char*& source_file, uint32_t& line_number) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static bool (*is_sensitive_thread_hook_)();
   static uint32_t lock_profiling_threshold_;
@@ -172,7 +172,7 @@
   void Add(Monitor* m);
 
   void SweepMonitorList(Heap::IsMarkedTester is_marked, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
  private:
   Mutex monitor_list_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
diff --git a/src/mutex.cc b/src/mutex.cc
index 2811843..cb344d4 100644
--- a/src/mutex.cc
+++ b/src/mutex.cc
@@ -75,16 +75,16 @@
   // ...other stuff we don't care about.
 };
 
-ReaderWriterMutex* GlobalSynchronization::mutator_lock_ = NULL;
-Mutex* GlobalSynchronization::thread_list_lock_ = NULL;
-Mutex* GlobalSynchronization::classlinker_classes_lock_ = NULL;
-ReaderWriterMutex* GlobalSynchronization::heap_bitmap_lock_ = NULL;
-Mutex* GlobalSynchronization::abort_lock_ = NULL;
-Mutex* GlobalSynchronization::logging_lock_ = NULL;
-Mutex* GlobalSynchronization::unexpected_signal_lock_ = NULL;
-Mutex* GlobalSynchronization::thread_suspend_count_lock_ = NULL;
+ReaderWriterMutex* Locks::mutator_lock_ = NULL;
+Mutex* Locks::thread_list_lock_ = NULL;
+Mutex* Locks::classlinker_classes_lock_ = NULL;
+ReaderWriterMutex* Locks::heap_bitmap_lock_ = NULL;
+Mutex* Locks::abort_lock_ = NULL;
+Mutex* Locks::logging_lock_ = NULL;
+Mutex* Locks::unexpected_signal_lock_ = NULL;
+Mutex* Locks::thread_suspend_count_lock_ = NULL;
 
-void GlobalSynchronization::Init() {
+void Locks::Init() {
   if (logging_lock_ != NULL) {
     // Already initialized.
     DCHECK(mutator_lock_ != NULL);
diff --git a/src/mutex.h b/src/mutex.h
index be3704c..5154d45 100644
--- a/src/mutex.h
+++ b/src/mutex.h
@@ -65,7 +65,7 @@
 std::ostream& operator<<(std::ostream& os, const MutexLevel& rhs);
 
 // Global mutexes corresponding to the levels above.
-class GlobalSynchronization {
+class Locks {
  public:
   static void Init();
 
diff --git a/src/native/dalvik_system_DexFile.cc b/src/native/dalvik_system_DexFile.cc
index 30f411c..b5e1c19 100644
--- a/src/native/dalvik_system_DexFile.cc
+++ b/src/native/dalvik_system_DexFile.cc
@@ -108,7 +108,7 @@
 }
 
 static const DexFile* toDexFile(int dex_file_address)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   const DexFile* dex_file = reinterpret_cast<const DexFile*>(static_cast<uintptr_t>(dex_file_address));
   if (dex_file == NULL) {
     Thread::Current()->ThrowNewExceptionF("Ljava/lang/NullPointerException;", "dex_file == null");
diff --git a/src/native/dalvik_system_VMRuntime.cc b/src/native/dalvik_system_VMRuntime.cc
index ed61de9..fae06f6 100644
--- a/src/native/dalvik_system_VMRuntime.cc
+++ b/src/native/dalvik_system_VMRuntime.cc
@@ -138,7 +138,7 @@
 #if !defined(ART_USE_LLVM_COMPILER)
     if (vm->check_jni) {
       LOG(WARNING) << "Turning off CheckJNI so we can turn on JNI app bug workarounds...";
-      MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+      MutexLock mu(*Locks::thread_list_lock_);
       vm->SetCheckJniEnabled(false);
       runtime->GetThreadList()->ForEach(DisableCheckJniCallback, NULL);
     }
diff --git a/src/native/java_lang_Class.cc b/src/native/java_lang_Class.cc
index e63cf1a..68fc97e 100644
--- a/src/native/java_lang_Class.cc
+++ b/src/native/java_lang_Class.cc
@@ -28,7 +28,7 @@
 namespace art {
 
 static Class* DecodeClass(const ScopedObjectAccess& soa, jobject java_class)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Class* c = soa.Decode<Class*>(java_class);
   DCHECK(c != NULL);
   DCHECK(c->IsClass());
@@ -93,7 +93,7 @@
 template<typename T>
 static jobjectArray ToArray(const ScopedObjectAccessUnchecked& soa, const char* array_class_name,
                             const std::vector<T*>& objects)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ScopedLocalRef<jclass> array_class(soa.Env(), soa.Env()->FindClass(array_class_name));
   jobjectArray result = soa.Env()->NewObjectArray(objects.size(), array_class.get(), NULL);
   for (size_t i = 0; i < objects.size(); ++i) {
@@ -240,7 +240,7 @@
 }
 
 static bool MethodMatches(MethodHelper* mh, const std::string& name, ObjectArray<Class>* arg_array)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (name != mh->GetName()) {
     return false;
   }
@@ -262,7 +262,7 @@
 
 static Method* FindConstructorOrMethodInArray(ObjectArray<Method>* methods, const std::string& name,
                                               ObjectArray<Class>* arg_array)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (methods == NULL) {
     return NULL;
   }
diff --git a/src/native/java_lang_System.cc b/src/native/java_lang_System.cc
index f4fe6ca..d74c9db 100644
--- a/src/native/java_lang_System.cc
+++ b/src/native/java_lang_System.cc
@@ -102,7 +102,7 @@
 namespace art {
 
 static void ThrowArrayStoreException_NotAnArray(const char* identifier, Object* array)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   std::string actualType(PrettyTypeOf(array));
   Thread::Current()->ThrowNewExceptionF("Ljava/lang/ArrayStoreException;",
       "%s of type %s is not an array", identifier, actualType.c_str());
diff --git a/src/native/java_lang_Thread.cc b/src/native/java_lang_Thread.cc
index a0c90ee..adc246a 100644
--- a/src/native/java_lang_Thread.cc
+++ b/src/native/java_lang_Thread.cc
@@ -35,7 +35,7 @@
 
 static jboolean Thread_isInterrupted(JNIEnv* env, jobject java_thread) {
   ScopedObjectAccess soa(env);
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Thread* thread = Thread::FromManagedThread(soa, java_thread);
   return (thread != NULL) ? thread->IsInterrupted() : JNI_FALSE;
 }
@@ -56,10 +56,10 @@
 
   ScopedObjectAccess soa(env);
   ThreadState internal_thread_state = (has_been_started ? kTerminated : kStarting);
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Thread* thread = Thread::FromManagedThread(soa, java_thread);
   if (thread != NULL) {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     internal_thread_state = thread->GetState();
   }
   switch (internal_thread_state) {
@@ -92,14 +92,14 @@
     Thread::Current()->ThrowNewException("Ljava/lang/NullPointerException;", "object == null");
     return JNI_FALSE;
   }
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Thread* thread = Thread::FromManagedThread(soa, java_thread);
   return thread->HoldsLock(object);
 }
 
 static void Thread_nativeInterrupt(JNIEnv* env, jobject java_thread) {
   ScopedObjectAccess soa(env);
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Thread* thread = Thread::FromManagedThread(soa, java_thread);
   if (thread != NULL) {
     thread->Interrupt();
@@ -140,7 +140,7 @@
  */
 static void Thread_nativeSetPriority(JNIEnv* env, jobject java_thread, jint new_priority) {
   ScopedObjectAccess soa(env);
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Thread* thread = Thread::FromManagedThread(soa, java_thread);
   if (thread != NULL) {
     thread->SetNativePriority(new_priority);
diff --git a/src/native/java_lang_reflect_Array.cc b/src/native/java_lang_reflect_Array.cc
index fa59750..49a4694 100644
--- a/src/native/java_lang_reflect_Array.cc
+++ b/src/native/java_lang_reflect_Array.cc
@@ -25,7 +25,7 @@
 // Recursively create an array with multiple dimensions.  Elements may be
 // Objects or primitive types.
 static Array* CreateMultiArray(Class* array_class, int current_dimension, IntArray* dimensions)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   int32_t array_length = dimensions->Get(current_dimension++);
   SirtRef<Array> new_array(Array::Alloc(array_class, array_length));
   if (new_array.get() == NULL) {
diff --git a/src/native/java_lang_reflect_Field.cc b/src/native/java_lang_reflect_Field.cc
index e764b25..c82e503 100644
--- a/src/native/java_lang_reflect_Field.cc
+++ b/src/native/java_lang_reflect_Field.cc
@@ -25,7 +25,7 @@
 
 static bool GetFieldValue(const ScopedObjectAccess& soa, Object* o, Field* f,
                           JValue& value, bool allow_references)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DCHECK_EQ(value.GetJ(), 0LL);
   if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(f->GetDeclaringClass(),
                                                                true, true)) {
@@ -74,7 +74,7 @@
 
 static bool CheckReceiver(const ScopedObjectAccess& soa, jobject javaObj, Field* f,
                           Object*& o)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (f->IsStatic()) {
     o = NULL;
     return true;
@@ -163,7 +163,7 @@
 }
 
 static void SetFieldValue(Object* o, Field* f, const JValue& new_value, bool allow_references)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(f->GetDeclaringClass(),
                                                                true, true)) {
     return;
diff --git a/src/native/org_apache_harmony_dalvik_ddmc_DdmVmInternal.cc b/src/native/org_apache_harmony_dalvik_ddmc_DdmVmInternal.cc
index 9bcea04..8e5bbf6 100644
--- a/src/native/org_apache_harmony_dalvik_ddmc_DdmVmInternal.cc
+++ b/src/native/org_apache_harmony_dalvik_ddmc_DdmVmInternal.cc
@@ -56,7 +56,7 @@
   };
   ThreadFinder finder(thin_lock_id);
   {
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
     Runtime::Current()->GetThreadList()->ForEach(ThreadFinder::Callback, &finder);
   }
   if (finder.thread != NULL) {
@@ -134,7 +134,7 @@
   std::vector<uint8_t>& bytes = *reinterpret_cast<std::vector<uint8_t>*>(context);
   JDWP::Append4BE(bytes, t->GetThinLockId());
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     JDWP::Append1BE(bytes, t->GetState());
   }
   JDWP::Append4BE(bytes, t->GetTid());
@@ -146,7 +146,7 @@
 static jbyteArray DdmVmInternal_getThreadStats(JNIEnv* env, jclass) {
   std::vector<uint8_t> bytes;
   {
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
     ThreadList* thread_list = Runtime::Current()->GetThreadList();
 
     uint16_t thread_count = 0;
diff --git a/src/oat/runtime/callee_save_frame.h b/src/oat/runtime/callee_save_frame.h
index 14ba046..9288a95 100644
--- a/src/oat/runtime/callee_save_frame.h
+++ b/src/oat/runtime/callee_save_frame.h
@@ -25,9 +25,9 @@
 
 // Place a special frame at the TOS that will save the callee saves for the given type.
 static void  FinishCalleeSaveFrameSetup(Thread* self, Method** sp, Runtime::CalleeSaveType type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Be aware the store below may well stomp on an incoming argument.
-  GlobalSynchronization::mutator_lock_->AssertSharedHeld();
+  Locks::mutator_lock_->AssertSharedHeld();
   *sp = Runtime::Current()->GetCalleeSaveMethod(type);
   self->SetTopOfStack(sp, 0);
   self->VerifyStack();
diff --git a/src/oat/runtime/stub.h b/src/oat/runtime/stub.h
index 9e5e66f..0e5f0dd 100644
--- a/src/oat/runtime/stub.h
+++ b/src/oat/runtime/stub.h
@@ -23,29 +23,29 @@
 
 namespace arm {
   ByteArray* CreateAbstractMethodErrorStub()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   ByteArray* ArmCreateResolutionTrampoline(Runtime::TrampolineType type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   ByteArray* CreateJniDlsymLookupStub()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 }
 
 namespace mips {
   ByteArray* CreateAbstractMethodErrorStub()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   ByteArray* MipsCreateResolutionTrampoline(Runtime::TrampolineType type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   ByteArray* CreateJniDlsymLookupStub()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 }
 
 namespace x86 {
   ByteArray* CreateAbstractMethodErrorStub()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   ByteArray* X86CreateResolutionTrampoline(Runtime::TrampolineType type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   ByteArray* CreateJniDlsymLookupStub()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 }
 
 }  // namespace art
diff --git a/src/oat/runtime/support_alloc.cc b/src/oat/runtime/support_alloc.cc
index 528198d..fb83fad 100644
--- a/src/oat/runtime/support_alloc.cc
+++ b/src/oat/runtime/support_alloc.cc
@@ -21,21 +21,21 @@
 
 extern "C" Object* artAllocObjectFromCode(uint32_t type_idx, Method* method,
                                           Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsOnly);
   return AllocObjectFromCode(type_idx, method, self, false);
 }
 
 extern "C" Object* artAllocObjectFromCodeWithAccessCheck(uint32_t type_idx, Method* method,
                                                          Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsOnly);
   return AllocObjectFromCode(type_idx, method, self, true);
 }
 
 extern "C" Array* artAllocArrayFromCode(uint32_t type_idx, Method* method, int32_t component_count,
                                         Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsOnly);
   return AllocArrayFromCode(type_idx, method, component_count, false);
 }
@@ -43,14 +43,14 @@
 extern "C" Array* artAllocArrayFromCodeWithAccessCheck(uint32_t type_idx, Method* method,
                                                        int32_t component_count,
                                                        Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsOnly);
   return AllocArrayFromCode(type_idx, method, component_count, true);
 }
 
 extern "C" Array* artCheckAndAllocArrayFromCode(uint32_t type_idx, Method* method,
                                                int32_t component_count, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsOnly);
   return CheckAndAllocArrayFromCode(type_idx, method, component_count, self, false);
 }
@@ -58,7 +58,7 @@
 extern "C" Array* artCheckAndAllocArrayFromCodeWithAccessCheck(uint32_t type_idx, Method* method,
                                                                int32_t component_count,
                                                                Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsOnly);
   return CheckAndAllocArrayFromCode(type_idx, method, component_count, self, true);
 }
diff --git a/src/oat/runtime/support_cast.cc b/src/oat/runtime/support_cast.cc
index ea083f1..45a3e60 100644
--- a/src/oat/runtime/support_cast.cc
+++ b/src/oat/runtime/support_cast.cc
@@ -21,7 +21,7 @@
 
 // Assignable test for code, won't throw.  Null and equality tests already performed
 extern "C" uint32_t artIsAssignableFromCode(const Class* klass, const Class* ref_class)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DCHECK(klass != NULL);
   DCHECK(ref_class != NULL);
   return klass->IsAssignableFrom(ref_class) ? 1 : 0;
@@ -29,7 +29,7 @@
 
 // Check whether it is safe to cast one class to the other, throw exception and return -1 on failure
 extern "C" int artCheckCastFromCode(const Class* a, const Class* b, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DCHECK(a->IsClass()) << PrettyClass(a);
   DCHECK(b->IsClass()) << PrettyClass(b);
   if (LIKELY(b->IsAssignableFrom(a))) {
@@ -48,7 +48,7 @@
 // Returns 0 on success and -1 if an exception is pending.
 extern "C" int artCanPutArrayElementFromCode(const Object* element, const Class* array_class,
                                              Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DCHECK(array_class != NULL);
   // element can't be NULL as we catch this is screened in runtime_support
   Class* element_class = element->GetClass();
diff --git a/src/oat/runtime/support_debug.cc b/src/oat/runtime/support_debug.cc
index 9968043..9eaf55b 100644
--- a/src/oat/runtime/support_debug.cc
+++ b/src/oat/runtime/support_debug.cc
@@ -26,14 +26,14 @@
  * to denote method entry.
  */
 extern "C" void artUpdateDebuggerFromCode(int32_t dex_pc, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp,  Runtime::kRefsAndArgs);
   Dbg::UpdateDebugger(dex_pc, self);
 }
 
 // Temporary debugging hook for compiler.
 extern void DebugMe(Method* method, uint32_t info)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   LOG(INFO) << "DebugMe";
   if (method != NULL) {
     LOG(INFO) << PrettyMethod(method);
diff --git a/src/oat/runtime/support_dexcache.cc b/src/oat/runtime/support_dexcache.cc
index 8e7c2ad..98cce55 100644
--- a/src/oat/runtime/support_dexcache.cc
+++ b/src/oat/runtime/support_dexcache.cc
@@ -21,7 +21,7 @@
 
 extern "C" Class* artInitializeStaticStorageFromCode(uint32_t type_idx, const Method* referrer,
                                                      Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Called to ensure static storage base is initialized for direct static field reads and writes.
   // A class may be accessing another class' fields when it doesn't have access, as access has been
   // given by inheritance.
@@ -31,7 +31,7 @@
 
 extern "C" Class* artInitializeTypeFromCode(uint32_t type_idx, const Method* referrer, Thread* self,
                                             Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Called when method->dex_cache_resolved_types_[] misses.
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsOnly);
   return ResolveVerifyAndClinit(type_idx, referrer, self, false, false);
@@ -40,7 +40,7 @@
 extern "C" Class* artInitializeTypeAndVerifyAccessFromCode(uint32_t type_idx,
                                                            const Method* referrer, Thread* self,
                                                            Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Called when caller isn't guaranteed to have access to a type and the dex cache may be
   // unpopulated.
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsOnly);
@@ -49,7 +49,7 @@
 
 extern "C" String* artResolveStringFromCode(Method* referrer, int32_t string_idx,
                                             Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsOnly);
   return ResolveStringFromCode(referrer, string_idx);
 }
diff --git a/src/oat/runtime/support_field.cc b/src/oat/runtime/support_field.cc
index fe8974b..90a99da 100644
--- a/src/oat/runtime/support_field.cc
+++ b/src/oat/runtime/support_field.cc
@@ -23,7 +23,7 @@
 
 extern "C" uint32_t artGet32StaticFromCode(uint32_t field_idx, const Method* referrer,
                                            Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticPrimitiveRead, sizeof(int32_t));
   if (LIKELY(field != NULL)) {
     return field->Get32(NULL);
@@ -38,7 +38,7 @@
 
 extern "C" uint64_t artGet64StaticFromCode(uint32_t field_idx, const Method* referrer,
                                            Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticPrimitiveRead, sizeof(int64_t));
   if (LIKELY(field != NULL)) {
     return field->Get64(NULL);
@@ -53,7 +53,7 @@
 
 extern "C" Object* artGetObjStaticFromCode(uint32_t field_idx, const Method* referrer,
                                            Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticObjectRead, sizeof(Object*));
   if (LIKELY(field != NULL)) {
     return field->GetObj(NULL);
@@ -68,7 +68,7 @@
 
 extern "C" uint32_t artGet32InstanceFromCode(uint32_t field_idx, Object* obj,
                                              const Method* referrer, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstancePrimitiveRead, sizeof(int32_t));
   if (LIKELY(field != NULL && obj != NULL)) {
     return field->Get32(obj);
@@ -87,7 +87,7 @@
 
 extern "C" uint64_t artGet64InstanceFromCode(uint32_t field_idx, Object* obj,
                                              const Method* referrer, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstancePrimitiveRead, sizeof(int64_t));
   if (LIKELY(field != NULL && obj != NULL)) {
     return field->Get64(obj);
@@ -106,7 +106,7 @@
 
 extern "C" Object* artGetObjInstanceFromCode(uint32_t field_idx, Object* obj,
                                               const Method* referrer, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstanceObjectRead, sizeof(Object*));
   if (LIKELY(field != NULL && obj != NULL)) {
     return field->GetObj(obj);
@@ -125,7 +125,7 @@
 
 extern "C" int artSet32StaticFromCode(uint32_t field_idx, uint32_t new_value,
                                       const Method* referrer, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticPrimitiveWrite, sizeof(int32_t));
   if (LIKELY(field != NULL)) {
     field->Set32(NULL, new_value);
@@ -142,7 +142,7 @@
 
 extern "C" int artSet64StaticFromCode(uint32_t field_idx, const Method* referrer,
                                       uint64_t new_value, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticPrimitiveWrite, sizeof(int64_t));
   if (LIKELY(field != NULL)) {
     field->Set64(NULL, new_value);
@@ -159,7 +159,7 @@
 
 extern "C" int artSetObjStaticFromCode(uint32_t field_idx, Object* new_value,
                                        const Method* referrer, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, StaticObjectWrite, sizeof(Object*));
   if (LIKELY(field != NULL)) {
     if (LIKELY(!FieldHelper(field).IsPrimitiveType())) {
@@ -178,7 +178,7 @@
 
 extern "C" int artSet32InstanceFromCode(uint32_t field_idx, Object* obj, uint32_t new_value,
                                         const Method* referrer, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstancePrimitiveWrite, sizeof(int32_t));
   if (LIKELY(field != NULL && obj != NULL)) {
     field->Set32(obj, new_value);
@@ -199,7 +199,7 @@
 
 extern "C" int artSet64InstanceFromCode(uint32_t field_idx, Object* obj, uint64_t new_value,
                                         Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Method* callee_save = Runtime::Current()->GetCalleeSaveMethod(Runtime::kRefsOnly);
   Method* referrer = sp[callee_save->GetFrameSizeInBytes() / sizeof(Method*)];
   Field* field = FindFieldFast(field_idx, referrer, InstancePrimitiveWrite, sizeof(int64_t));
@@ -223,7 +223,7 @@
 
 extern "C" int artSetObjInstanceFromCode(uint32_t field_idx, Object* obj, Object* new_value,
                                          const Method* referrer, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* field = FindFieldFast(field_idx, referrer, InstanceObjectWrite, sizeof(Object*));
   if (LIKELY(field != NULL && obj != NULL)) {
     field->SetObj(obj, new_value);
diff --git a/src/oat/runtime/support_fillarray.cc b/src/oat/runtime/support_fillarray.cc
index 8561bd8..62b9cf9 100644
--- a/src/oat/runtime/support_fillarray.cc
+++ b/src/oat/runtime/support_fillarray.cc
@@ -38,7 +38,7 @@
 extern "C" int artHandleFillArrayDataFromCode(Array* array,
                                               const Instruction::ArrayDataPayload* payload,
                                               Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsOnly);
   DCHECK_EQ(payload->ident, static_cast<uint16_t>(Instruction::kArrayDataSignature));
   if (UNLIKELY(array == NULL)) {
diff --git a/src/oat/runtime/support_invoke.cc b/src/oat/runtime/support_invoke.cc
index b2867ef..540e46b 100644
--- a/src/oat/runtime/support_invoke.cc
+++ b/src/oat/runtime/support_invoke.cc
@@ -21,7 +21,7 @@
 
 static uint64_t artInvokeCommon(uint32_t method_idx, Object* this_object, Method* caller_method,
                                 Thread* self, Method** sp, bool access_check, InvokeType type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Method* method = FindMethodFast(method_idx, this_object, caller_method, access_check, type);
   if (UNLIKELY(method == NULL)) {
     FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsAndArgs);
@@ -56,7 +56,7 @@
 extern "C" uint64_t artInvokeInterfaceTrampoline(uint32_t method_idx, Object* this_object,
                                                  Method* caller_method, Thread* self,
                                                  Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return artInvokeCommon(method_idx, this_object, caller_method, self, sp, false, kInterface);
 }
 
@@ -64,7 +64,7 @@
                                                                 Object* this_object,
                                                                 Method* caller_method, Thread* self,
                                                                 Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return artInvokeCommon(method_idx, this_object, caller_method, self, sp, true, kInterface);
 }
 
@@ -73,7 +73,7 @@
                                                              Object* this_object,
                                                              Method* caller_method, Thread* self,
                                                              Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return artInvokeCommon(method_idx, this_object, caller_method, self, sp, true, kDirect);
 }
 
@@ -81,7 +81,7 @@
                                                             Object* this_object,
                                                             Method* caller_method, Thread* self,
                                                             Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return artInvokeCommon(method_idx, this_object, caller_method, self, sp, true, kStatic);
 }
 
@@ -89,7 +89,7 @@
                                                             Object* this_object,
                                                             Method* caller_method, Thread* self,
                                                             Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return artInvokeCommon(method_idx, this_object, caller_method, self, sp, true, kSuper);
 }
 
@@ -97,7 +97,7 @@
                                                               Object* this_object,
                                                               Method* caller_method, Thread* self,
                                                               Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   return artInvokeCommon(method_idx, this_object, caller_method, self, sp, true, kVirtual);
 }
 
diff --git a/src/oat/runtime/support_jni.cc b/src/oat/runtime/support_jni.cc
index 5c0bbee..49365b5 100644
--- a/src/oat/runtime/support_jni.cc
+++ b/src/oat/runtime/support_jni.cc
@@ -23,8 +23,8 @@
 namespace art {
 
 // Used by the JNI dlsym stub to find the native method to invoke if none is registered.
-extern void* FindNativeMethod(Thread* self) LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_) {
-  GlobalSynchronization::mutator_lock_->AssertNotHeld();  // We come here as Native.
+extern void* FindNativeMethod(Thread* self) LOCKS_EXCLUDED(Locks::mutator_lock_) {
+  Locks::mutator_lock_->AssertNotHeld();  // We come here as Native.
   DCHECK(Thread::Current() == self);
   ScopedObjectAccess soa(self);
 
@@ -54,7 +54,7 @@
 }
 
 extern uint32_t JniMethodStartSynchronized(jobject to_lock, Thread* self)
-    UNLOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+    UNLOCK_FUNCTION(Locks::mutator_lock_) {
   self->DecodeJObject(to_lock)->MonitorEnter(self);
   return JniMethodStart(self);
 }
@@ -67,14 +67,14 @@
 }
 
 extern void JniMethodEnd(uint32_t saved_local_ref_cookie, Thread* self)
-    SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCK_FUNCTION(Locks::mutator_lock_) {
   self->TransitionFromSuspendedToRunnable();
   PopLocalReferences(saved_local_ref_cookie, self);
 }
 
 
 extern void JniMethodEndSynchronized(uint32_t saved_local_ref_cookie, jobject locked, Thread* self)
-    SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCK_FUNCTION(Locks::mutator_lock_) {
   self->TransitionFromSuspendedToRunnable();
   UnlockJniSynchronizedMethod(locked, self);  // Must decode before pop.
   PopLocalReferences(saved_local_ref_cookie, self);
@@ -82,7 +82,7 @@
 
 extern Object* JniMethodEndWithReference(jobject result, uint32_t saved_local_ref_cookie,
                                          Thread* self)
-    SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCK_FUNCTION(Locks::mutator_lock_) {
   self->TransitionFromSuspendedToRunnable();
   Object* o = self->DecodeJObject(result);  // Must decode before pop.
   PopLocalReferences(saved_local_ref_cookie, self);
@@ -99,7 +99,7 @@
 extern Object* JniMethodEndWithReferenceSynchronized(jobject result,
                                                      uint32_t saved_local_ref_cookie,
                                                      jobject locked, Thread* self)
-    SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCK_FUNCTION(Locks::mutator_lock_) {
   self->TransitionFromSuspendedToRunnable();
   UnlockJniSynchronizedMethod(locked, self);  // Must decode before pop.
   Object* o = self->DecodeJObject(result);
@@ -123,7 +123,7 @@
 }
 
 extern "C" const void* artWorkAroundAppJniBugs(Thread* self, intptr_t* sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_){
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_){
   DCHECK(Thread::Current() == self);
   // TODO: this code is specific to ARM
   // On entry the stack pointed by sp is:
diff --git a/src/oat/runtime/support_proxy.cc b/src/oat/runtime/support_proxy.cc
index c224484..8c40aba 100644
--- a/src/oat/runtime/support_proxy.cc
+++ b/src/oat/runtime/support_proxy.cc
@@ -48,7 +48,7 @@
 // the invocation handler which is a field within the proxy object receiver.
 extern "C" void artProxyInvokeHandler(Method* proxy_method, Object* receiver,
                                       Thread* self, byte* stack_args)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Register the top of the managed stack
   Method** proxy_sp = reinterpret_cast<Method**>(stack_args - SP_OFFSET_IN_BYTES);
   DCHECK_EQ(*proxy_sp, proxy_method);
diff --git a/src/oat/runtime/support_stubs.cc b/src/oat/runtime/support_stubs.cc
index 510df3b..41de9f7 100644
--- a/src/oat/runtime/support_stubs.cc
+++ b/src/oat/runtime/support_stubs.cc
@@ -34,7 +34,7 @@
 // Lazily resolve a method. Called by stub code.
 const void* UnresolvedDirectMethodTrampolineFromCode(Method* called, Method** sp, Thread* thread,
                                                      Runtime::TrampolineType type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
 #if defined(__arm__)
   // On entry the stack pointed by sp is:
   // | argN       |  |
@@ -230,7 +230,7 @@
 #else // ART_USE_LLVM_COMPILER
 const void* UnresolvedDirectMethodTrampolineFromCode(Method* called, Method** called_addr,
                                                      Thread* thread, Runtime::TrampolineType type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   uint32_t dex_pc;
   Method* caller = thread->GetCurrentMethod(&dex_pc);
 
@@ -323,7 +323,7 @@
 #if !defined(ART_USE_LLVM_COMPILER)
 // Called by the AbstractMethodError. Called by stub code.
 extern void ThrowAbstractMethodErrorFromCode(Method* method, Thread* thread, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(thread, sp, Runtime::kSaveAll);
   thread->ThrowNewExceptionF("Ljava/lang/AbstractMethodError;",
                              "abstract method \"%s\"", PrettyMethod(method).c_str());
@@ -331,7 +331,7 @@
 }
 #else // ART_USE_LLVM_COMPILER
 extern void ThrowAbstractMethodErrorFromCode(Method* method, Thread* thread, Method**)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   thread->ThrowNewExceptionF("Ljava/lang/AbstractMethodError;",
                              "abstract method \"%s\"", PrettyMethod(method).c_str());
 }
diff --git a/src/oat/runtime/support_thread.cc b/src/oat/runtime/support_thread.cc
index 32284bb..20fe3e5 100644
--- a/src/oat/runtime/support_thread.cc
+++ b/src/oat/runtime/support_thread.cc
@@ -21,14 +21,14 @@
 namespace art {
 
 void CheckSuspendFromCode(Thread* thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Called when thread->suspend_count_ != 0 on JNI return. JNI method acts as callee-save frame.
   thread->VerifyStack();
   thread->FullSuspendCheck();
 }
 
 extern "C" void artTestSuspendFromCode(Thread* thread, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Called when suspend count check value is 0 and thread->suspend_count_ != 0
   FinishCalleeSaveFrameSetup(thread, sp, Runtime::kRefsOnly);
   thread->FullSuspendCheck();
diff --git a/src/oat/runtime/support_throw.cc b/src/oat/runtime/support_throw.cc
index 0abdb04..6e1e101 100644
--- a/src/oat/runtime/support_throw.cc
+++ b/src/oat/runtime/support_throw.cc
@@ -24,14 +24,14 @@
 
 // Deliver an exception that's pending on thread helping set up a callee save frame on the way.
 extern "C" void artDeliverPendingExceptionFromCode(Thread* thread, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(thread, sp, Runtime::kSaveAll);
   thread->DeliverException();
 }
 
 // Called by generated call to throw an exception.
 extern "C" void artDeliverExceptionFromCode(Throwable* exception, Thread* thread, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   /*
    * exception may be NULL, in which case this routine should
    * throw NPE.  NOTE: this is a convenience for generated code,
@@ -50,7 +50,7 @@
 
 // Called by generated call to throw a NPE exception.
 extern "C" void artThrowNullPointerExceptionFromCode(Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kSaveAll);
   uint32_t dex_pc;
   Method* throw_method = self->GetCurrentMethod(&dex_pc);
@@ -60,7 +60,7 @@
 
 // Called by generated call to throw an arithmetic divide by zero exception.
 extern "C" void artThrowDivZeroFromCode(Thread* thread, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(thread, sp, Runtime::kSaveAll);
   thread->ThrowNewException("Ljava/lang/ArithmeticException;", "divide by zero");
   thread->DeliverException();
@@ -68,7 +68,7 @@
 
 // Called by generated call to throw an array index out of bounds exception.
 extern "C" void artThrowArrayBoundsFromCode(int index, int limit, Thread* thread, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(thread, sp, Runtime::kSaveAll);
   thread->ThrowNewExceptionF("Ljava/lang/ArrayIndexOutOfBoundsException;",
                              "length=%d; index=%d", limit, index);
@@ -76,7 +76,7 @@
 }
 
 extern "C" void artThrowStackOverflowFromCode(Thread* thread, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(thread, sp, Runtime::kSaveAll);
   // Remove extra entry pushed onto second stack during method tracing.
   if (Runtime::Current()->IsMethodTracingActive()) {
@@ -90,7 +90,7 @@
 }
 
 extern "C" void artThrowNoSuchMethodFromCode(int32_t method_idx, Thread* self, Method** sp)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   FinishCalleeSaveFrameSetup(self, sp, Runtime::kSaveAll);
   Method* method = self->GetCurrentMethod();
   ThrowNoSuchMethodError(method_idx, method);
diff --git a/src/oat_test.cc b/src/oat_test.cc
index 288854b..0886864 100644
--- a/src/oat_test.cc
+++ b/src/oat_test.cc
@@ -26,7 +26,7 @@
   void CheckMethod(Method* method,
                    const OatFile::OatMethod& oat_method,
                    const DexFile* dex_file)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const CompiledMethod* compiled_method =
         compiler_->GetCompiledMethod(Compiler::MethodReference(dex_file,
                                                                method->GetDexMethodIndex()));
diff --git a/src/oat_writer.h b/src/oat_writer.h
index 200d695..fd8e2b2 100644
--- a/src/oat_writer.h
+++ b/src/oat_writer.h
@@ -69,14 +69,14 @@
                      uint32_t image_file_location_checksum,
                      const std::string& image_file_location,
                      const Compiler& compiler)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
  private:
   OatWriter(const std::vector<const DexFile*>& dex_files,
             uint32_t image_file_location_checksum,
             const std::string& image_file_location,
             jobject class_loader,
-            const Compiler& compiler) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+            const Compiler& compiler) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   ~OatWriter();
 
   size_t InitOatHeader();
@@ -85,20 +85,20 @@
   size_t InitOatClasses(size_t offset);
   size_t InitOatCode(size_t offset);
   size_t InitOatCodeDexFiles(size_t offset)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   size_t InitOatCodeDexFile(size_t offset,
                             size_t& oat_class_index,
                             const DexFile& dex_file)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   size_t InitOatCodeClassDef(size_t offset,
                              size_t oat_class_index, size_t class_def_index,
                              const DexFile& dex_file,
                              const DexFile::ClassDef& class_def)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   size_t InitOatCodeMethod(size_t offset, size_t oat_class_index, size_t class_def_index,
                            size_t class_def_method_index, bool is_native, InvokeType type,
                            uint32_t method_idx, const DexFile*)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool Write(File* file);
   bool WriteTables(File* file);
diff --git a/src/oatdump.cc b/src/oatdump.cc
index cde4dc6..e0ee148 100644
--- a/src/oatdump.cc
+++ b/src/oatdump.cc
@@ -156,7 +156,7 @@
     return oat_file_.GetOatHeader().GetInstructionSet();
   }
 
-  const void* GetOatCode(Method* m) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const void* GetOatCode(Method* m) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     MethodHelper mh(m);
     for (size_t i = 0; i < oat_dex_files_.size(); i++) {
       const OatFile::OatDexFile* oat_dex_file = oat_dex_files_[i];
@@ -487,7 +487,7 @@
       : os_(os), image_filename_(image_filename), host_prefix_(host_prefix),
         image_space_(image_space), image_header_(image_header) {}
 
-  void Dump() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void Dump() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     os_ << "MAGIC:\n";
     os_ << image_header_.GetMagic() << "\n\n";
 
@@ -558,10 +558,10 @@
     Heap* heap = Runtime::Current()->GetHeap();
     const Spaces& spaces = heap->GetSpaces();
     {
-      WriterMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+      WriterMutexLock mu(*Locks::heap_bitmap_lock_);
       heap->FlushAllocStack();
     }
-    ReaderMutexLock mu(*GlobalSynchronization::heap_bitmap_lock_);
+    ReaderMutexLock mu(*Locks::heap_bitmap_lock_);
     // TODO: C++0x auto
     for (Spaces::const_iterator cur = spaces.begin(); cur != spaces.end(); ++cur) {
       (*cur)->GetLiveBitmap()->Walk(ImageDumper::Callback, this);
@@ -585,7 +585,7 @@
 
  private:
   static void PrettyObjectValue(std::string& summary, Class* type, Object* value)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK(type != NULL);
     if (value == NULL) {
       StringAppendF(&summary, "null   %s\n", PrettyDescriptor(type).c_str());
@@ -607,7 +607,7 @@
   }
 
   static void PrintField(std::string& summary, Field* field, Object* obj)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     FieldHelper fh(field);
     const char* descriptor = fh.GetTypeDescriptor();
     StringAppendF(&summary, "\t%s: ", fh.GetName());
@@ -636,7 +636,7 @@
   }
 
   static void DumpFields(std::string& summary, Object* obj, Class* klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Class* super = klass->GetSuperClass();
     if (super != NULL) {
       DumpFields(summary, obj, super);
@@ -655,7 +655,7 @@
   }
 
   const void* GetOatCodeBegin(Method* m)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Runtime* runtime = Runtime::Current();
     const void* code = m->GetCode();
     if (code == runtime->GetResolutionStubArray(Runtime::kStaticMethod)->GetData()) {
@@ -668,7 +668,7 @@
   }
 
   uint32_t GetOatCodeSize(Method* m)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const uint32_t* oat_code_begin = reinterpret_cast<const uint32_t*>(GetOatCodeBegin(m));
     if (oat_code_begin == NULL) {
       return 0;
@@ -677,7 +677,7 @@
   }
 
   const void* GetOatCodeEnd(Method* m)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const uint8_t* oat_code_begin = reinterpret_cast<const uint8_t*>(GetOatCodeBegin(m));
     if (oat_code_begin == NULL) {
       return NULL;
@@ -686,7 +686,7 @@
   }
 
   static void Callback(Object* obj, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(obj != NULL);
     DCHECK(arg != NULL);
     ImageDumper* state = reinterpret_cast<ImageDumper*>(arg);
@@ -945,7 +945,7 @@
     }
 
     void DumpOutliers(std::ostream& os)
-        SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
       size_t sum_of_sizes = 0;
       size_t sum_of_sizes_squared = 0;
       size_t sum_of_expansion = 0;
@@ -1045,7 +1045,7 @@
       os << "\n" << std::flush;
     }
 
-    void Dump(std::ostream& os) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    void Dump(std::ostream& os) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
       os << "\tart_file_bytes = " << PrettySize(file_bytes) << "\n\n"
          << "\tart_file_bytes = header_bytes + object_bytes + alignment_bytes\n"
          << StringPrintf("\theader_bytes    =  %8zd (%2.0f%% of art file bytes)\n"
diff --git a/src/object.cc b/src/object.cc
index 83994ff..cde7e04 100644
--- a/src/object.cc
+++ b/src/object.cc
@@ -439,7 +439,7 @@
 }
 
 static const void* GetOatCode(const Method* m)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Runtime* runtime = Runtime::Current();
   const void* code = m->GetCode();
   // Peel off any method tracing trampoline.
@@ -529,7 +529,7 @@
 void Method::Invoke(Thread* self, Object* receiver, JValue* args, JValue* result) const {
   if (kIsDebugBuild) {
     self->AssertThreadSuspensionIsAllowable();
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_EQ(kRunnable, self->GetState());
   }
 
diff --git a/src/object.h b/src/object.h
index c20c99a..36db13d 100644
--- a/src/object.h
+++ b/src/object.h
@@ -172,11 +172,11 @@
   void SetClass(Class* new_klass);
 
   bool InstanceOf(const Class* klass) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  size_t SizeOf() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  size_t SizeOf() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  Object* Clone() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  Object* Clone() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   int32_t IdentityHashCode() const {
   #ifdef MOVING_GARBAGE_COLLECTOR
@@ -199,20 +199,20 @@
 
   uint32_t GetThinLockId();
 
-  void MonitorEnter(Thread* thread) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+  void MonitorEnter(Thread* thread) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       EXCLUSIVE_LOCK_FUNCTION(monitor_lock_);
 
-  bool MonitorExit(Thread* thread) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+  bool MonitorExit(Thread* thread) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       UNLOCK_FUNCTION(monitor_lock_);
 
-  void Notify() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void Notify() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void NotifyAll() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void NotifyAll() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void Wait(int64_t timeout) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void Wait(int64_t timeout) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void Wait(int64_t timeout, int32_t nanos)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool IsClass() const;
 
@@ -260,14 +260,14 @@
     return down_cast<const Method*>(this);
   }
 
-  bool IsField() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool IsField() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  Field* AsField() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  Field* AsField() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(IsField());
     return down_cast<Field*>(this);
   }
 
-  const Field* AsField() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const Field* AsField() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(IsField());
     return down_cast<const Field*>(this);
   }
@@ -424,55 +424,55 @@
 
   // field access, null object for static fields
   bool GetBoolean(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetBoolean(Object* object, bool z) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   int8_t GetByte(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetByte(Object* object, int8_t b) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   uint16_t GetChar(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetChar(Object* object, uint16_t c) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   int16_t GetShort(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetShort(Object* object, int16_t s) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   int32_t GetInt(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetInt(Object* object, int32_t i) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   int64_t GetLong(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetLong(Object* object, int64_t j) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   float GetFloat(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetFloat(Object* object, float f) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   double GetDouble(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetDouble(Object* object, double d) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   Object* GetObject(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetObject(Object* object, const Object* l) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // raw field accesses
   uint32_t Get32(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void Set32(Object* object, uint32_t new_value) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   uint64_t Get64(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void Set64(Object* object, uint64_t new_value) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   Object* GetObj(const Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void SetObj(Object* object, const Object* new_value) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static Class* GetJavaLangReflectField() {
     DCHECK(java_lang_reflect_Field_ != NULL);
@@ -652,10 +652,10 @@
   void SetDexCacheInitializedStaticStorage(ObjectArray<StaticStorageBase>* new_value);
 
   // Find the method that this method overrides
-  Method* FindOverriddenMethod() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  Method* FindOverriddenMethod() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void Invoke(Thread* self, Object* receiver, JValue* args, JValue* result) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   const void* GetCode() const {
     return GetFieldPtr<const void*>(OFFSET_OF_OBJECT_MEMBER(Method, code_), false);
@@ -665,7 +665,7 @@
     SetFieldPtr<const void*>(OFFSET_OF_OBJECT_MEMBER(Method, code_), code, false);
   }
 
-  uint32_t GetCodeSize() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  uint32_t GetCodeSize() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(!IsRuntimeMethod() && !IsProxyMethod()) << PrettyMethod(this);
     uintptr_t code = reinterpret_cast<uintptr_t>(GetCode());
     if (code == 0) {
@@ -677,7 +677,7 @@
   }
 
   bool IsWithinCode(uintptr_t pc) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     uintptr_t code = reinterpret_cast<uintptr_t>(GetCode());
     if (code == 0) {
       return pc == 0;
@@ -686,7 +686,7 @@
   }
 
   void AssertPcIsWithinCode(uintptr_t pc) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   uint32_t GetOatCodeOffset() const {
     DCHECK(!Runtime::Current()->IsStarted());
@@ -811,9 +811,9 @@
   bool IsRegistered() const;
 
   void RegisterNative(Thread* self, const void* native_method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void UnregisterNative(Thread* self) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void UnregisterNative(Thread* self) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static MemberOffset NativeMethodOffset() {
     return OFFSET_OF_OBJECT_MEMBER(Method, native_method_);
@@ -914,16 +914,16 @@
   // Converts a native PC to a dex PC.  TODO: this is a no-op
   // until we associate a PC mapping table with each method.
   uint32_t ToDexPC(const uintptr_t pc) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Converts a dex PC to a native PC.  TODO: this is a no-op
   // until we associate a PC mapping table with each method.
   uintptr_t ToNativePC(const uint32_t dex_pc) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Find the catch block for the given exception type and dex_pc
   uint32_t FindCatchBlock(Class* exception_type, uint32_t dex_pc) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void SetClasses(Class* java_lang_reflect_Constructor, Class* java_lang_reflect_Method);
 
@@ -1014,10 +1014,10 @@
   // A convenience for code that doesn't know the component size,
   // and doesn't want to have to work it out itself.
   static Array* Alloc(Class* array_class, int32_t component_count)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static Array* Alloc(Class* array_class, int32_t component_count, size_t component_size)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   size_t SizeOf() const;
 
@@ -1055,7 +1055,7 @@
 
  protected:
   bool IsValidIndex(int32_t index) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (UNLIKELY(index < 0 || index >= length_)) {
       return ThrowArrayIndexOutOfBoundsException(index);
     }
@@ -1064,9 +1064,9 @@
 
  protected:
   bool ThrowArrayIndexOutOfBoundsException(int32_t index) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   bool ThrowArrayStoreException(Object* object) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
  private:
   // The number of array elements.
@@ -1081,26 +1081,26 @@
 class MANAGED ObjectArray : public Array {
  public:
   static ObjectArray<T>* Alloc(Class* object_array_class, int32_t length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  T* Get(int32_t i) const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  T* Get(int32_t i) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void Set(int32_t i, T* object) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void Set(int32_t i, T* object) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Set element without bound and element type checks, to be used in limited
   // circumstances, such as during boot image writing
   void SetWithoutChecks(int32_t i, T* object)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  T* GetWithoutChecks(int32_t i) const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  T* GetWithoutChecks(int32_t i) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void Copy(const ObjectArray<T>* src, int src_pos,
                    ObjectArray<T>* dst, int dst_pos,
                    size_t length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   ObjectArray<T>* CopyOf(int32_t new_length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(ObjectArray);
@@ -1191,7 +1191,7 @@
     return static_cast<Status>(GetField32(OFFSET_OF_OBJECT_MEMBER(Class, status_), false));
   }
 
-  void SetStatus(Status new_status) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void SetStatus(Status new_status) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Returns true if the class has failed to link.
   bool IsErroneous() const {
@@ -1302,7 +1302,7 @@
   String* GetName() const; // Returns the cached name
   void SetName(String* name);  // Sets the cached name
   String* ComputeName()  // Computes the name, then sets the cached value
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool IsProxyClass() const {
     // Read access flags without using getter as whether something is a proxy can be check in
@@ -1381,7 +1381,7 @@
 
   bool IsStringClass() const;
 
-  bool IsThrowableClass() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool IsThrowableClass() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Class* GetComponentType() const {
     return GetFieldObject<Class*>(OFFSET_OF_OBJECT_MEMBER(Class, component_type_), false);
@@ -1405,7 +1405,7 @@
   }
 
   // Creates a raw object instance but does not invoke the default constructor.
-  Object* AllocObject() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  Object* AllocObject() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool IsVariableSize() const {
     // Classes and arrays vary in size, and so the object_size_ field cannot
@@ -1424,9 +1424,9 @@
   }
 
   void SetClassSize(size_t new_class_size)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  size_t GetObjectSize() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t GetObjectSize() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK(!IsVariableSize()) << " class=" << PrettyTypeOf(this);
     DCHECK_EQ(sizeof(size_t), sizeof(int32_t));
     size_t result = GetField32(OFFSET_OF_OBJECT_MEMBER(Class, object_size_), false);
@@ -1442,12 +1442,12 @@
 
   // Returns true if this class is in the same packages as that class.
   bool IsInSamePackage(const Class* that) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static bool IsInSamePackage(const StringPiece& descriptor1, const StringPiece& descriptor2);
 
   // Returns true if this class can access that class.
-  bool CanAccess(Class* that) const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool CanAccess(Class* that) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return that->IsPublic() || this->IsInSamePackage(that);
   }
 
@@ -1455,7 +1455,7 @@
   // Note that access to the class isn't checked in case the declaring class is protected and the
   // method has been exposed by a public sub-class
   bool CanAccessMember(Class* access_to, uint32_t member_flags) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     // Classes can access all of their own members
     if (this == access_to) {
       return true;
@@ -1479,7 +1479,7 @@
   }
 
   bool IsSubClass(const Class* klass) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Can src be assigned to this class? For example, String can be assigned to Object (by an
   // upcast), however, an Object cannot be assigned to a String as a potentially exception throwing
@@ -1487,7 +1487,7 @@
   // that extends) another can be assigned to its parent, but not vice-versa. All Classes may assign
   // to themselves. Classes for primitive types may not assign to each other.
   bool IsAssignableFrom(const Class* src) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(src != NULL);
     if (this == src) {
       // Can always assign to things of the same type
@@ -1543,7 +1543,7 @@
   };
 
   void DumpClass(std::ostream& os, int flags) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   DexCache* GetDexCache() const;
 
@@ -1564,12 +1564,12 @@
   }
 
   Method* GetDirectMethod(int32_t i) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetDirectMethods()->Get(i);
   }
 
   void SetDirectMethod(uint32_t i, Method* f)  // TODO: uint16_t
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_){
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_){
     ObjectArray<Method>* direct_methods =
         GetFieldObject<ObjectArray<Method>*>(
             OFFSET_OF_OBJECT_MEMBER(Class, direct_methods_), false);
@@ -1601,19 +1601,19 @@
   }
 
   Method* GetVirtualMethod(uint32_t i) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(IsResolved() || IsErroneous());
     return GetVirtualMethods()->Get(i);
   }
 
   Method* GetVirtualMethodDuringLinking(uint32_t i) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(IsLoaded() || IsErroneous());
     return GetVirtualMethods()->Get(i);
   }
 
   void SetVirtualMethod(uint32_t i, Method* f)  // TODO: uint16_t
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ObjectArray<Method>* virtual_methods =
         GetFieldObject<ObjectArray<Method>*>(
             OFFSET_OF_OBJECT_MEMBER(Class, virtual_methods_), false);
@@ -1642,7 +1642,7 @@
   // super class, return the specific implementation
   // method for this class.
   Method* FindVirtualMethodForVirtual(Method* method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(!method->GetDeclaringClass()->IsInterface());
     // The argument method may from a super class.
     // Use the index to a potentially overridden one for this instance's class.
@@ -1653,16 +1653,16 @@
   // super class or interface, return the specific implementation
   // method for this class.
   Method* FindVirtualMethodForInterface(Method* method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* FindInterfaceMethod(const StringPiece& name, const StringPiece& descriptor) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* FindInterfaceMethod(const DexCache* dex_cache, uint32_t dex_method_idx) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* FindVirtualMethodForVirtualOrInterface(Method* method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (method->IsDirect()) {
       return method;
     }
@@ -1673,28 +1673,28 @@
   }
 
   Method* FindDeclaredVirtualMethod(const StringPiece& name, const StringPiece& signature) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* FindDeclaredVirtualMethod(const DexCache* dex_cache, uint32_t dex_method_idx) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* FindVirtualMethod(const StringPiece& name, const StringPiece& descriptor) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* FindVirtualMethod(const DexCache* dex_cache, uint32_t dex_method_idx) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* FindDeclaredDirectMethod(const StringPiece& name, const StringPiece& signature) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* FindDeclaredDirectMethod(const DexCache* dex_cache, uint32_t dex_method_idx) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* FindDirectMethod(const StringPiece& name, const StringPiece& signature) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* FindDirectMethod(const DexCache* dex_cache, uint32_t dex_method_idx) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   int32_t GetIfTableCount() const {
     ObjectArray<InterfaceEntry>* iftable = GetIfTable();
@@ -1731,13 +1731,13 @@
   }
 
   Field* GetInstanceField(uint32_t i) const  // TODO: uint16_t
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_){
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_){
     DCHECK_NE(NumInstanceFields(), 0U);
     return GetIFields()->Get(i);
   }
 
   void SetInstanceField(uint32_t i, Field* f)  // TODO: uint16_t
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_){
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_){
     ObjectArray<Field>* ifields= GetFieldObject<ObjectArray<Field>*>(
         OFFSET_OF_OBJECT_MEMBER(Class, ifields_), false);
     ifields->Set(i, f);
@@ -1808,12 +1808,12 @@
   }
 
   Field* GetStaticField(uint32_t i) const  // TODO: uint16_t
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetSFields()->Get(i);
   }
 
   void SetStaticField(uint32_t i, Field* f)  // TODO: uint16_t
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ObjectArray<Field>* sfields= GetFieldObject<ObjectArray<Field>*>(
         OFFSET_OF_OBJECT_MEMBER(Class, sfields_), false);
     sfields->Set(i, f);
@@ -1827,37 +1827,37 @@
 
   // Find a static or instance field using the JLS resolution order
   Field* FindField(const StringPiece& name, const StringPiece& type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Finds the given instance field in this class or a superclass.
   Field* FindInstanceField(const StringPiece& name, const StringPiece& type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Finds the given instance field in this class or a superclass, only searches classes that
   // have the same dex cache.
   Field* FindInstanceField(const DexCache* dex_cache, uint32_t dex_field_idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Field* FindDeclaredInstanceField(const StringPiece& name, const StringPiece& type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Field* FindDeclaredInstanceField(const DexCache* dex_cache, uint32_t dex_field_idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Finds the given static field in this class or a superclass.
   Field* FindStaticField(const StringPiece& name, const StringPiece& type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Finds the given static field in this class or superclass, only searches classes that
   // have the same dex cache.
   Field* FindStaticField(const DexCache* dex_cache, uint32_t dex_field_idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Field* FindDeclaredStaticField(const StringPiece& name, const StringPiece& type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Field* FindDeclaredStaticField(const DexCache* dex_cache, uint32_t dex_field_idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   pid_t GetClinitThreadId() const {
     DCHECK(IsIdxLoaded() || IsErroneous());
@@ -1883,17 +1883,17 @@
 
  private:
   void SetVerifyErrorClass(Class* klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK(klass != NULL) << PrettyClass(this);
     SetFieldObject(OFFSET_OF_OBJECT_MEMBER(Class, verify_error_class_), klass, false);
   }
 
   bool Implements(const Class* klass) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   bool IsArrayAssignableFromArray(const Class* klass) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   bool IsAssignableFromArray(const Class* klass) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // defining class loader, or NULL for the "bootstrap" system loader
   ClassLoader* class_loader_;
@@ -2233,7 +2233,7 @@
   typedef T ElementType;
 
   static PrimitiveArray<T>* Alloc(size_t length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   const T* GetData() const {
     intptr_t data = reinterpret_cast<intptr_t>(this) + DataOffset(sizeof(T)).Int32Value();
@@ -2245,14 +2245,14 @@
     return reinterpret_cast<T*>(data);
   }
 
-  T Get(int32_t i) const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  T Get(int32_t i) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (!IsValidIndex(i)) {
       return T(0);
     }
     return GetData()[i];
   }
 
-  void Set(int32_t i, T value) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void Set(int32_t i, T value) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     // TODO: ArrayStoreException
     if (IsValidIndex(i)) {
       GetData()[i] = value;
@@ -2306,9 +2306,9 @@
 
   int32_t GetLength() const;
 
-  int32_t GetHashCode() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  int32_t GetHashCode() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void ComputeHashCode() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void ComputeHashCode() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     SetHashCode(ComputeUtf16Hash(GetCharArray(), GetOffset(), GetLength()));
   }
 
@@ -2316,36 +2316,36 @@
     return CountUtf8Bytes(GetCharArray()->GetData() + GetOffset(), GetLength());
   }
 
-  uint16_t CharAt(int32_t index) const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  uint16_t CharAt(int32_t index) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  String* Intern() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  String* Intern() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static String* AllocFromUtf16(int32_t utf16_length,
                                 const uint16_t* utf16_data_in,
                                 int32_t hash_code = 0)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static String* AllocFromModifiedUtf8(const char* utf)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static String* AllocFromModifiedUtf8(int32_t utf16_length,
                                        const char* utf8_data_in)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static String* Alloc(Class* java_lang_String, int32_t utf16_length)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static String* Alloc(Class* java_lang_String, CharArray* array)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool Equals(const char* modified_utf8) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // TODO: do we need this overload? give it a more intention-revealing name.
   bool Equals(const StringPiece& modified_utf8) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  bool Equals(const String* that) const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool Equals(const String* that) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Compare UTF-16 code point values not in a locale-sensitive manner
   int Compare(int32_t utf16_length, const char* utf8_data_in);
@@ -2353,7 +2353,7 @@
   // TODO: do we need this overload? give it a more intention-revealing name.
   bool Equals(const uint16_t* that_chars, int32_t that_offset,
               int32_t that_length) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Create a modified UTF-8 encoded std::string from a java/lang/String object.
   std::string ToModifiedUtf8() const;
@@ -2471,7 +2471,7 @@
       return IsDirect() || !(methods_class->IsInterface() || methods_class->IsObjectClass());
     }
     default:
-      LOG(FATAL) << "UNREACHABLE";
+      LOG(FATAL) << "Unreachable - invocation type: " << type;
       return true;
   }
 }
@@ -2511,13 +2511,13 @@
   String* GetDetailMessage() const {
     return GetFieldObject<String*>(OFFSET_OF_OBJECT_MEMBER(Throwable, detail_message_), false);
   }
-  std::string Dump() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  std::string Dump() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // This is a runtime version of initCause, you shouldn't use it if initCause may have been
   // overridden. Also it asserts rather than throwing exceptions. Currently this is only used
   // in cases like the verifier where the checks cannot fail and initCause isn't overridden.
   void SetCause(Throwable* cause);
-  bool IsCheckedException() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool IsCheckedException() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static Class* GetJavaLangThrowable() {
     DCHECK(java_lang_Throwable_ != NULL);
@@ -2572,7 +2572,7 @@
                                   String* method_name,
                                   String* file_name,
                                   int32_t line_number)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void SetClass(Class* java_lang_StackTraceElement);
 
@@ -2598,20 +2598,20 @@
 
 class MANAGED InterfaceEntry : public ObjectArray<Object> {
  public:
-  Class* GetInterface() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  Class* GetInterface() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Class* interface = Get(kInterface)->AsClass();
     DCHECK(interface != NULL);
     return interface;
   }
 
-  void SetInterface(Class* interface) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void SetInterface(Class* interface) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(interface != NULL);
     DCHECK(interface->IsInterface());
     DCHECK(Get(kInterface) == NULL);
     Set(kInterface, interface);
   }
 
-  size_t GetMethodArrayCount() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t GetMethodArrayCount() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ObjectArray<Method>* method_array = down_cast<ObjectArray<Method>*>(Get(kMethodArray));
     if (method_array == NULL) {
       return 0;
@@ -2620,14 +2620,14 @@
   }
 
   ObjectArray<Method>* GetMethodArray() const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ObjectArray<Method>* method_array = down_cast<ObjectArray<Method>*>(Get(kMethodArray));
     DCHECK(method_array != NULL);
     return method_array;
   }
 
   void SetMethodArray(ObjectArray<Method>* new_ma)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(new_ma != NULL);
     DCHECK(Get(kMethodArray) == NULL);
     Set(kMethodArray, new_ma);
diff --git a/src/object_test.cc b/src/object_test.cc
index e44cf64..081be4b 100644
--- a/src/object_test.cc
+++ b/src/object_test.cc
@@ -35,7 +35,7 @@
                     const char* utf8_in,
                     const char* utf16_expected_le,
                     int32_t expected_hash)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     UniquePtr<uint16_t[]> utf16_expected(new uint16_t[length]);
     for (int32_t i = 0; i < length; i++) {
       uint16_t ch = (((utf16_expected_le[i*2 + 0] & 0xff) << 8) |
diff --git a/src/object_utils.h b/src/object_utils.h
index d523ecc..f6158f3 100644
--- a/src/object_utils.h
+++ b/src/object_utils.h
@@ -32,25 +32,25 @@
 
 class ObjectLock {
  public:
-  explicit ObjectLock(Object* object) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+  explicit ObjectLock(Object* object) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : self_(Thread::Current()), obj_(object) {
     CHECK(object != NULL);
     obj_->MonitorEnter(self_);
   }
 
-  ~ObjectLock() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  ~ObjectLock() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     obj_->MonitorExit(self_);
   }
 
-  void Wait() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void Wait() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return Monitor::Wait(self_, obj_, 0, 0, false);
   }
 
-  void Notify() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void Notify() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     obj_->Notify();
   }
 
-  void NotifyAll() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void NotifyAll() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     obj_->NotifyAll();
   }
 
@@ -63,7 +63,7 @@
 class ClassHelper {
  public:
   ClassHelper(const Class* c = NULL, ClassLinker* l = NULL)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : class_def_(NULL),
         class_linker_(l),
         dex_cache_(NULL),
@@ -76,7 +76,7 @@
   }
 
   void ChangeClass(const Class* new_c)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK(new_c != NULL) << "klass_=" << klass_;  // Log what we were changing from if any
     CHECK(new_c->IsClass()) << "new_c=" << new_c;
     if (dex_cache_ != NULL) {
@@ -93,7 +93,7 @@
 
   // The returned const char* is only guaranteed to be valid for the lifetime of the ClassHelper.
   // If you need it longer, copy it into a std::string.
-  const char* GetDescriptor() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const char* GetDescriptor() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK(klass_ != NULL);
     if (UNLIKELY(klass_->IsArrayClass())) {
       return GetArrayDescriptor();
@@ -109,7 +109,7 @@
     }
   }
 
-  const char* GetArrayDescriptor() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const char* GetArrayDescriptor() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     std::string result("[");
     const Class* saved_klass = klass_;
     CHECK(saved_klass != NULL);
@@ -121,7 +121,7 @@
   }
 
   const DexFile::ClassDef* GetClassDef()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile::ClassDef* result = class_def_;
     if (result == NULL) {
       result = GetDexFile().FindClassDef(GetDescriptor());
@@ -130,7 +130,7 @@
     return result;
   }
 
-  uint32_t NumDirectInterfaces() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  uint32_t NumDirectInterfaces() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(klass_ != NULL);
     if (klass_->IsPrimitive()) {
       return 0;
@@ -149,7 +149,7 @@
   }
 
   uint16_t GetDirectInterfaceTypeIdx(uint32_t idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(klass_ != NULL);
     DCHECK(!klass_->IsPrimitive());
     DCHECK(!klass_->IsArrayClass());
@@ -157,7 +157,7 @@
   }
 
   Class* GetDirectInterface(uint32_t idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(klass_ != NULL);
     DCHECK(!klass_->IsPrimitive());
     if (klass_->IsArrayClass()) {
@@ -180,7 +180,7 @@
     }
   }
 
-  const char* GetSourceFile() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const char* GetSourceFile() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     std::string descriptor(GetDescriptor());
     const DexFile& dex_file = GetDexFile();
     const DexFile::ClassDef* dex_class_def = dex_file.FindClassDef(descriptor);
@@ -188,7 +188,7 @@
     return dex_file.GetSourceFile(*dex_class_def);
   }
 
-  std::string GetLocation() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  std::string GetLocation() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DexCache* dex_cache = GetDexCache();
     if (dex_cache != NULL && !klass_->IsProxyClass()) {
       return dex_cache->GetLocation()->ToModifiedUtf8();
@@ -198,7 +198,7 @@
     }
   }
 
-  const DexFile& GetDexFile() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const DexFile& GetDexFile() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile* result = dex_file_;
     if (result == NULL) {
       const DexCache* dex_cache = GetDexCache();
@@ -208,7 +208,7 @@
     return *result;
   }
 
-  DexCache* GetDexCache() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  DexCache* GetDexCache() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DexCache* result = dex_cache_;
     if (result == NULL) {
       DCHECK(klass_ != NULL);
@@ -220,7 +220,7 @@
 
  private:
   const DexFile::TypeList* GetInterfaceTypeList()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile::TypeList* result = interface_type_list_;
     if (result == NULL) {
       const DexFile::ClassDef* class_def = GetClassDef();
@@ -270,7 +270,7 @@
     }
     field_ = new_f;
   }
-  const char* GetName() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const char* GetName() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     uint32_t field_index = field_->GetDexFieldIndex();
     if (!field_->GetDeclaringClass()->IsProxyClass()) {
       const DexFile& dex_file = GetDexFile();
@@ -291,7 +291,7 @@
       return Runtime::Current()->GetInternTable()->InternStrong(GetName());
     }
   }
-  Class* GetType() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  Class* GetType() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     uint32_t field_index = field_->GetDexFieldIndex();
     if (!field_->GetDeclaringClass()->IsProxyClass()) {
       const DexFile& dex_file = GetDexFile();
@@ -306,7 +306,7 @@
       return GetClassLinker()->FindSystemClass(GetTypeDescriptor());
     }
   }
-  const char* GetTypeDescriptor() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const char* GetTypeDescriptor() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     uint32_t field_index = field_->GetDexFieldIndex();
     if (!field_->GetDeclaringClass()->IsProxyClass()) {
       const DexFile& dex_file = GetDexFile();
@@ -320,14 +320,14 @@
     }
   }
   Primitive::Type GetTypeAsPrimitiveType()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return Primitive::GetType(GetTypeDescriptor()[0]);
   }
-  bool IsPrimitiveType() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool IsPrimitiveType() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Primitive::Type type = GetTypeAsPrimitiveType();
     return type != Primitive::kPrimNot;
   }
-  size_t FieldSize() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t FieldSize() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Primitive::Type type = GetTypeAsPrimitiveType();
     return Primitive::FieldSize(type);
   }
@@ -335,7 +335,7 @@
   // The returned const char* is only guaranteed to be valid for the lifetime of the FieldHelper.
   // If you need it longer, copy it into a std::string.
   const char* GetDeclaringClassDescriptor()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     uint16_t type_idx = field_->GetDeclaringClass()->GetDexTypeIndex();
     if (type_idx != DexFile::kDexNoIndex16) {
       const DexFile& dex_file = GetDexFile();
@@ -349,7 +349,7 @@
   }
 
  private:
-  DexCache* GetDexCache() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  DexCache* GetDexCache() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DexCache* result = dex_cache_;
     if (result == NULL) {
       result = field_->GetDeclaringClass()->GetDexCache();
@@ -365,7 +365,7 @@
     }
     return result;
   }
-  const DexFile& GetDexFile() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const DexFile& GetDexFile() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile* result = dex_file_;
     if (result == NULL) {
       const DexCache* dex_cache = GetDexCache();
@@ -391,20 +391,20 @@
        shorty_len_(0) {}
 
   explicit MethodHelper(const Method* m)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : class_linker_(NULL), dex_cache_(NULL), dex_file_(NULL), method_(NULL), shorty_(NULL),
         shorty_len_(0) {
     SetMethod(m);
   }
 
   MethodHelper(const Method* m, ClassLinker* l)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : class_linker_(l), dex_cache_(NULL), dex_file_(NULL), method_(NULL), shorty_(NULL),
         shorty_len_(0) {
     SetMethod(m);
   }
 
-  void ChangeMethod(Method* new_m) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void ChangeMethod(Method* new_m) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(new_m != NULL);
     if (dex_cache_ != NULL) {
       Class* klass = new_m->GetDeclaringClass();
@@ -423,7 +423,7 @@
     shorty_ = NULL;
   }
 
-  const char* GetName() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const char* GetName() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile& dex_file = GetDexFile();
     uint32_t dex_method_idx = method_->GetDexMethodIndex();
     if (dex_method_idx != DexFile::kDexNoIndex16) {
@@ -444,15 +444,15 @@
     }
   }
 
-  String* GetNameAsString() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  String* GetNameAsString() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile& dex_file = GetDexFile();
     uint32_t dex_method_idx = method_->GetDexMethodIndex();
     const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx);
     return GetClassLinker()->ResolveString(dex_file, method_id.name_idx_, GetDexCache());
   }
 
-  const char* GetShorty() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const char* GetShorty() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const char* result = shorty_;
     if (result == NULL) {
       const DexFile& dex_file = GetDexFile();
@@ -463,14 +463,14 @@
     return result;
   }
 
-  uint32_t GetShortyLength() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  uint32_t GetShortyLength() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (shorty_ == NULL) {
       GetShorty();
     }
     return shorty_len_;
   }
 
-  const std::string GetSignature() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const std::string GetSignature() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile& dex_file = GetDexFile();
     uint32_t dex_method_idx = method_->GetDexMethodIndex();
     if (dex_method_idx != DexFile::kDexNoIndex16) {
@@ -481,19 +481,19 @@
   }
 
   const DexFile::ProtoId& GetPrototype()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile& dex_file = GetDexFile();
     return dex_file.GetMethodPrototype(dex_file.GetMethodId(method_->GetDexMethodIndex()));
   }
 
   const DexFile::TypeList* GetParameterTypeList()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile::ProtoId& proto = GetPrototype();
     return GetDexFile().GetProtoParameters(proto);
   }
 
   ObjectArray<Class>* GetParameterTypes()
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile::TypeList* params = GetParameterTypeList();
     Class* array_class = GetClassLinker()->FindSystemClass("[Ljava/lang/Class;");
     uint32_t num_params = params == NULL ? 0 : params->Size();
@@ -509,7 +509,7 @@
     return result;
   }
 
-  Class* GetReturnType() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  Class* GetReturnType() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile& dex_file = GetDexFile();
     const DexFile::MethodId& method_id = dex_file.GetMethodId(method_->GetDexMethodIndex());
     const DexFile::ProtoId& proto_id = dex_file.GetMethodPrototype(method_id);
@@ -518,7 +518,7 @@
   }
 
   const char* GetReturnTypeDescriptor()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile& dex_file = GetDexFile();
     const DexFile::MethodId& method_id = dex_file.GetMethodId(method_->GetDexMethodIndex());
     const DexFile::ProtoId& proto_id = dex_file.GetMethodPrototype(method_id);
@@ -527,7 +527,7 @@
   }
 
   int32_t GetLineNumFromDexPC(uint32_t dex_pc)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (dex_pc == DexFile::kDexNoIndex) {
       return method_->IsNative() ? -2 : -1;
     } else {
@@ -537,7 +537,7 @@
   }
 
   const char* GetDeclaringClassDescriptor()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Class* klass = method_->GetDeclaringClass();
     DCHECK(!klass->IsProxyClass());
     uint16_t type_idx = klass->GetDexTypeIndex();
@@ -546,7 +546,7 @@
   }
 
   const char* GetDeclaringClassSourceFile()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const char* descriptor = GetDeclaringClassDescriptor();
     const DexFile& dex_file = GetDexFile();
     const DexFile::ClassDef* dex_class_def = dex_file.FindClassDef(descriptor);
@@ -555,7 +555,7 @@
   }
 
   uint32_t GetClassDefIndex()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const char* descriptor = GetDeclaringClassDescriptor();
     const DexFile& dex_file = GetDexFile();
     uint32_t index;
@@ -564,20 +564,20 @@
   }
 
   ClassLoader* GetClassLoader()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return method_->GetDeclaringClass()->GetClassLoader();
   }
 
   bool IsStatic()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return method_->IsStatic();
   }
 
-  bool IsClassInitializer() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool IsClassInitializer() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return IsStatic() && StringPiece(GetName()) == "<clinit>";
   }
 
-  size_t NumArgs() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t NumArgs() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     // "1 +" because the first in Args is the receiver.
     // "- 1" because we don't count the return type.
     return (IsStatic() ? 0 : 1) + GetShortyLength() - 1;
@@ -585,7 +585,7 @@
 
   // Is the specified parameter a long or double, where parameter 0 is 'this' for instance methods
   bool IsParamALongOrDouble(size_t param)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK_LT(param, NumArgs());
     if (IsStatic()) {
       param++;  // 0th argument must skip return value at start of the shorty
@@ -597,7 +597,7 @@
   }
 
   // Is the specified parameter a reference, where parameter 0 is 'this' for instance methods
-  bool IsParamAReference(size_t param) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool IsParamAReference(size_t param) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     CHECK_LT(param, NumArgs());
     if (IsStatic()) {
       param++;  // 0th argument must skip return value at start of the shorty
@@ -608,7 +608,7 @@
   }
 
   bool HasSameNameAndSignature(MethodHelper* other)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (GetDexCache() == other->GetDexCache()) {
       const DexFile& dex_file = GetDexFile();
       const DexFile::MethodId& mid = dex_file.GetMethodId(method_->GetDexMethodIndex());
@@ -622,17 +622,17 @@
   }
 
   const DexFile::CodeItem* GetCodeItem()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetDexFile().GetCodeItem(method_->GetCodeItemOffset());
   }
 
   bool IsResolvedTypeIdx(uint16_t type_idx) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return method_->GetDexCacheResolvedTypes()->Get(type_idx) != NULL;
   }
 
   Class* GetClassFromTypeIdx(uint16_t type_idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Class* type = method_->GetDexCacheResolvedTypes()->Get(type_idx);
     if (type == NULL) {
       type = GetClassLinker()->ResolveType(type_idx, method_);
@@ -642,17 +642,17 @@
   }
 
   const char* GetTypeDescriptorFromTypeIdx(uint16_t type_idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile& dex_file = GetDexFile();
     return dex_file.GetTypeDescriptor(dex_file.GetTypeId(type_idx));
   }
 
   Class* GetDexCacheResolvedType(uint16_t type_idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetDexCache()->GetResolvedType(type_idx);
   }
 
-  const DexFile& GetDexFile() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const DexFile& GetDexFile() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     const DexFile* result = dex_file_;
     if (result == NULL) {
       const DexCache* dex_cache = GetDexCache();
@@ -662,7 +662,7 @@
     return *result;
   }
 
-  DexCache* GetDexCache() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  DexCache* GetDexCache() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DexCache* result = dex_cache_;
     if (result == NULL) {
       Class* klass = method_->GetDeclaringClass();
@@ -676,7 +676,7 @@
   // Set the method_ field, for proxy methods looking up the interface method via the resolved
   // methods table.
   void SetMethod(const Method* method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (method != NULL) {
       Class* klass = method->GetDeclaringClass();
       if (klass->IsProxyClass()) {
diff --git a/src/reference_table.cc b/src/reference_table.cc
index a2b54d6..1f6cab7 100644
--- a/src/reference_table.cc
+++ b/src/reference_table.cc
@@ -63,7 +63,7 @@
   bool operator()(const Object* obj1, const Object* obj2)
     // TODO: enable analysis when analysis can work with the STL.
       NO_THREAD_SAFETY_ANALYSIS {
-    GlobalSynchronization::mutator_lock_->AssertSharedHeld();
+    Locks::mutator_lock_->AssertSharedHeld();
     // Ensure null references and cleared jweaks appear at the end.
     if (obj1 == NULL) {
       return true;
@@ -100,7 +100,7 @@
 // or equivalent to the original.
 static void DumpSummaryLine(std::ostream& os, const Object* obj, size_t element_count,
                             int identical, int equiv)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (obj == NULL) {
     os << "    NULL reference (count=" << equiv << ")\n";
     return;
diff --git a/src/reference_table.h b/src/reference_table.h
index de9d45d..f398eb2 100644
--- a/src/reference_table.h
+++ b/src/reference_table.h
@@ -43,14 +43,14 @@
 
   size_t Size() const;
 
-  void Dump(std::ostream& os) const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void Dump(std::ostream& os) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void VisitRoots(Heap::RootVisitor* visitor, void* arg);
 
  private:
   typedef std::vector<const Object*> Table;
   static void Dump(std::ostream& os, const Table& entries)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   friend class IndirectReferenceTable; // For Dump.
 
   std::string name_;
diff --git a/src/reflection.cc b/src/reflection.cc
index 542f1a2..7f1d4d1 100644
--- a/src/reflection.cc
+++ b/src/reflection.cc
@@ -235,7 +235,7 @@
   }
 
   if (kIsDebugBuild) {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_EQ(Thread::Current()->GetState(), kRunnable);
   }
   ScopedObjectAccessUnchecked soa(Thread::Current());
@@ -244,7 +244,7 @@
 }
 
 static std::string UnboxingFailureKind(Method* m, int index, Field* f)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (m != NULL && index != -1) {
     ++index; // Humans count from 1.
     return StringPrintf("method %s argument %d", PrettyMethod(m, false).c_str(), index);
@@ -257,7 +257,7 @@
 
 static bool UnboxPrimitive(Object* o, Class* dst_class, JValue& unboxed_value, Method* m,
                            int index, Field* f)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (!dst_class->IsPrimitive()) {
     if (o != NULL && !o->InstanceOf(dst_class)) {
       Thread::Current()->ThrowNewExceptionF("Ljava/lang/IllegalArgumentException;",
diff --git a/src/reflection.h b/src/reflection.h
index 2979e5b..93219f8 100644
--- a/src/reflection.h
+++ b/src/reflection.h
@@ -30,24 +30,24 @@
 class ScopedObjectAccess;
 
 void BoxPrimitive(Primitive::Type src_class, JValue& value)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 bool UnboxPrimitiveForArgument(Object* o, Class* dst_class, JValue& unboxed_value, Method* m,
                                size_t index)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 bool UnboxPrimitiveForField(Object* o, Class* dst_class, JValue& unboxed_value, Field* f)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 bool UnboxPrimitiveForResult(Object* o, Class* dst_class, JValue& unboxed_value)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 bool ConvertPrimitiveValue(Primitive::Type src_class, Primitive::Type dst_class, const JValue& src,
                            JValue& dst)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 jobject InvokeMethod(const ScopedObjectAccess& soa, jobject method, jobject receiver, jobject args)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 bool VerifyObjectInClass(Object* o, Class* c)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 }  // namespace art
 
diff --git a/src/runtime.cc b/src/runtime.cc
index 89477b0..f37788d 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -175,7 +175,7 @@
 void Runtime::Abort() {
   // Ensure that we don't have multiple threads trying to abort at once,
   // which would result in significantly worse diagnostics.
-  MutexLock mu(*GlobalSynchronization::abort_lock_);
+  MutexLock mu(*Locks::abort_lock_);
 
   // Get any pending output out of the way.
   fflush(NULL);
@@ -536,7 +536,7 @@
   if (Runtime::instance_ != NULL) {
     return false;
   }
-  GlobalSynchronization::Init();
+  Locks::Init();
   instance_ = new Runtime;
   if (!instance_->Init(options, ignore_unrecognized)) {
     delete instance_;
@@ -642,7 +642,7 @@
 
   // Must be in the kNative state for calling native methods.
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_EQ(self->GetState(), kNative);
   }
 
@@ -742,7 +742,7 @@
 
   // Must be in the kNative state for calling native methods (JNI_OnLoad code).
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_EQ(self->GetState(), kNative);
   }
 
@@ -831,7 +831,7 @@
 }
 
 void Runtime::DumpLockHolders(std::ostream& os) {
-  uint64_t mutator_lock_owner = GlobalSynchronization::mutator_lock_->GetExclusiveOwnerTid();
+  uint64_t mutator_lock_owner = Locks::mutator_lock_->GetExclusiveOwnerTid();
   pid_t thread_list_lock_owner = GetThreadList()->GetLockOwner();
   pid_t classes_lock_owner = GetClassLinker()->GetClassesLockOwner();
   pid_t dex_lock_owner = GetClassLinker()->GetDexLockOwner();
diff --git a/src/runtime.h b/src/runtime.h
index f613991..4dcefb5 100644
--- a/src/runtime.h
+++ b/src/runtime.h
@@ -97,7 +97,7 @@
 
   // Creates and initializes a new runtime.
   static bool Create(const Options& options, bool ignore_unrecognized)
-      SHARED_TRYLOCK_FUNCTION(true, GlobalSynchronization::mutator_lock_);
+      SHARED_TRYLOCK_FUNCTION(true, Locks::mutator_lock_);
 
   bool IsCompiler() const {
     return is_compiler_;
@@ -117,7 +117,7 @@
   }
 
   // Starts a runtime, which may cause threads to be started and code to run.
-  void Start() UNLOCK_FUNCTION(GlobalSynchronization::mutator_lock_);
+  void Start() UNLOCK_FUNCTION(Locks::mutator_lock_);
 
   bool IsShuttingDown() const {
     return shutting_down_;
@@ -140,7 +140,7 @@
   // This isn't marked ((noreturn)) because then gcc will merge multiple calls
   // in a single function together. This reduces code size slightly, but means
   // that the native stack trace we get may point at the wrong call site.
-  static void Abort() LOCKS_EXCLUDED(GlobalSynchronization::abort_lock_);
+  static void Abort() LOCKS_EXCLUDED(Locks::abort_lock_);
 
   // Returns the "main" ThreadGroup, used when attaching user threads.
   jobject GetMainThreadGroup() const;
@@ -154,10 +154,10 @@
   void CallExitHook(jint status);
 
   // Detaches the current native thread from the runtime.
-  void DetachCurrentThread() LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+  void DetachCurrentThread() LOCKS_EXCLUDED(Locks::mutator_lock_);
 
   void DumpForSigQuit(std::ostream& os)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void DumpLockHolders(std::ostream& os);
 
   ~Runtime();
@@ -211,7 +211,7 @@
   }
 
   void VisitRoots(Heap::RootVisitor* visitor, void* arg) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool HasJniDlsymLookupStub() const {
     return jni_stub_array_ != NULL;
@@ -267,7 +267,7 @@
     resolution_method_ = method;
   }
 
-  Method* CreateResolutionMethod() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  Method* CreateResolutionMethod() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Returns a special method that describes all callee saves being spilled to the stack.
   enum CalleeSaveType {
@@ -289,13 +289,13 @@
   void SetCalleeSaveMethod(Method* method, CalleeSaveType type);
 
   Method* CreateCalleeSaveMethod(InstructionSet instruction_set, CalleeSaveType type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* CreateRefOnlyCalleeSaveMethod(InstructionSet instruction_set)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* CreateRefAndArgsCalleeSaveMethod(InstructionSet instruction_set)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   int32_t GetStat(int kind);
 
@@ -341,8 +341,8 @@
   void BlockSignals();
 
   bool Init(const Options& options, bool ignore_unrecognized)
-      SHARED_TRYLOCK_FUNCTION(true, GlobalSynchronization::mutator_lock_);
-  void InitNativeMethods() LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_);
+      SHARED_TRYLOCK_FUNCTION(true, Locks::mutator_lock_);
+  void InitNativeMethods() LOCKS_EXCLUDED(Locks::mutator_lock_);
   void InitThreadGroups(Thread* self);
   void RegisterRuntimeNativeMethods(JNIEnv* env);
 
diff --git a/src/runtime_linux.cc b/src/runtime_linux.cc
index 8365079..e503358 100644
--- a/src/runtime_linux.cc
+++ b/src/runtime_linux.cc
@@ -226,7 +226,7 @@
 };
 
 static void HandleUnexpectedSignal(int signal_number, siginfo_t* info, void* raw_context) {
-  MutexLock mu(*GlobalSynchronization::unexpected_signal_lock_);
+  MutexLock mu(*Locks::unexpected_signal_lock_);
 
   bool has_address = (signal_number == SIGILL || signal_number == SIGBUS ||
                       signal_number == SIGFPE || signal_number == SIGSEGV);
diff --git a/src/runtime_support.h b/src/runtime_support.h
index 8f6b655..16f0d2e 100644
--- a/src/runtime_support.h
+++ b/src/runtime_support.h
@@ -50,7 +50,7 @@
 // check.
 static inline Object* AllocObjectFromCode(uint32_t type_idx, Method* method, Thread* self,
                                           bool access_check)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Class* klass = method->GetDexCacheResolvedTypes()->Get(type_idx);
   Runtime* runtime = Runtime::Current();
   if (UNLIKELY(klass == NULL)) {
@@ -85,7 +85,7 @@
 // check.
 static inline Array* AllocArrayFromCode(uint32_t type_idx, Method* method, int32_t component_count,
                                         bool access_check)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (UNLIKELY(component_count < 0)) {
     Thread::Current()->ThrowNewExceptionF("Ljava/lang/NegativeArraySizeException;", "%d",
                                           component_count);
@@ -112,7 +112,7 @@
 
 extern Array* CheckAndAllocArrayFromCode(uint32_t type_idx, Method* method, int32_t component_count,
                                          Thread* self, bool access_check)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 // Type of find field operation for fast and slow case.
 enum FindFieldType {
@@ -129,12 +129,12 @@
 // Slow field find that can initialize classes and may throw exceptions.
 extern Field* FindFieldFromCode(uint32_t field_idx, const Method* referrer, Thread* self,
                                 FindFieldType type, size_t expected_size)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 // Fast path field resolution that can't initialize classes or throw exceptions.
 static inline Field* FindFieldFast(uint32_t field_idx, const Method* referrer,
                                    FindFieldType type, size_t expected_size)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* resolved_field = referrer->GetDeclaringClass()->GetDexCache()->GetResolvedField(field_idx);
   if (UNLIKELY(resolved_field == NULL)) {
     return NULL;
@@ -183,7 +183,7 @@
 // Fast path method resolution that can't throw exceptions.
 static inline Method* FindMethodFast(uint32_t method_idx, Object* this_object,
                                      const Method* referrer, bool access_check, InvokeType type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   bool is_direct = type == kStatic || type == kDirect;
   if (UNLIKELY(this_object == NULL && !is_direct)) {
     return NULL;
@@ -223,20 +223,20 @@
 
 extern Method* FindMethodFromCode(uint32_t method_idx, Object* this_object, const Method* referrer,
                                   Thread* self, bool access_check, InvokeType type)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 extern Class* ResolveVerifyAndClinit(uint32_t type_idx, const Method* referrer, Thread* self,
                                      bool can_run_clinit, bool verify_access)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 static inline String* ResolveStringFromCode(const Method* referrer, uint32_t string_idx)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
   return class_linker->ResolveString(string_idx, referrer);
 }
 
 static inline void UnlockJniSynchronizedMethod(jobject locked, Thread* self)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
     UNLOCK_FUNCTION(monitor_lock_) {
   // Save any pending exception over monitor exit call.
   Throwable* saved_exception = NULL;
@@ -259,7 +259,7 @@
 }
 
 static inline void CheckReferenceResult(Object* o, Thread* self)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (o == NULL) {
     return;
   }
diff --git a/src/scoped_thread_state_change.h b/src/scoped_thread_state_change.h
index 745e2d6..ed3c384 100644
--- a/src/scoped_thread_state_change.h
+++ b/src/scoped_thread_state_change.h
@@ -29,7 +29,7 @@
 class ScopedThreadStateChange {
  public:
   ScopedThreadStateChange(Thread* self, ThreadState new_thread_state)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
       : self_(self), thread_state_(new_thread_state), expected_has_no_thread_(false) {
     if (self_ == NULL) {
       // Value chosen arbitrarily and won't be used in the destructor since thread_ == NULL.
@@ -38,7 +38,7 @@
     } else {
       bool runnable_transition;
       {
-        MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+        MutexLock mu(*Locks::thread_suspend_count_lock_);
         old_thread_state_ = self->GetState();
         runnable_transition = old_thread_state_ == kRunnable || new_thread_state == kRunnable;
         if (!runnable_transition) {
@@ -56,7 +56,7 @@
     }
   }
 
-  ~ScopedThreadStateChange() LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_) {
+  ~ScopedThreadStateChange() LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_) {
     if (self_ == NULL) {
       if (!expected_has_no_thread_) {
         CHECK(Runtime::Current()->IsShuttingDown());
@@ -68,7 +68,7 @@
         } else if (thread_state_ == kRunnable) {
           self_->TransitionFromRunnableToSuspended(old_thread_state_);
         } else {
-          MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+          MutexLock mu(*Locks::thread_suspend_count_lock_);
           self_->SetState(old_thread_state_);
         }
       }
@@ -112,14 +112,14 @@
 class ScopedObjectAccessUnchecked : public ScopedThreadStateChange {
  public:
   explicit ScopedObjectAccessUnchecked(JNIEnv* env)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
       : ScopedThreadStateChange(ThreadForEnv(env), kRunnable),
         env_(reinterpret_cast<JNIEnvExt*>(env)), vm_(env_->vm) {
     self_->VerifyStack();
   }
 
   explicit ScopedObjectAccessUnchecked(Thread* self)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
       : ScopedThreadStateChange(self, kRunnable),
         env_(reinterpret_cast<JNIEnvExt*>(self->GetJniEnv())),
         vm_(env_ != NULL ? env_->vm : NULL) {
@@ -158,7 +158,7 @@
    */
   template<typename T>
   T AddLocalReference(Object* obj) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK_EQ(thread_state_, kRunnable);  // Don't work with raw objects in non-runnable states.
     if (obj == NULL) {
       return NULL;
@@ -195,8 +195,8 @@
   T Decode(jobject obj) const
       LOCKS_EXCLUDED(JavaVMExt::globals_lock,
                      JavaVMExt::weak_globals_lock)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
-    GlobalSynchronization::mutator_lock_->AssertSharedHeld();
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+    Locks::mutator_lock_->AssertSharedHeld();
     DCHECK_EQ(thread_state_, kRunnable);  // Don't work with raw objects in non-runnable states.
     return down_cast<T>(Self()->DecodeJObject(obj));
   }
@@ -204,8 +204,8 @@
   Field* DecodeField(jfieldID fid) const
       LOCKS_EXCLUDED(JavaVMExt::globals_lock,
                      JavaVMExt::weak_globals_lock)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
-    GlobalSynchronization::mutator_lock_->AssertSharedHeld();
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+    Locks::mutator_lock_->AssertSharedHeld();
     DCHECK_EQ(thread_state_, kRunnable);  // Don't work with raw objects in non-runnable states.
 #ifdef MOVING_GARBAGE_COLLECTOR
     // TODO: we should make these unique weak globals if Field instances can ever move.
@@ -217,8 +217,8 @@
   jfieldID EncodeField(Field* field) const
       LOCKS_EXCLUDED(JavaVMExt::globals_lock,
                      JavaVMExt::weak_globals_lock)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
-    GlobalSynchronization::mutator_lock_->AssertSharedHeld();
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+    Locks::mutator_lock_->AssertSharedHeld();
     DCHECK_EQ(thread_state_, kRunnable);  // Don't work with raw objects in non-runnable states.
 #ifdef MOVING_GARBAGE_COLLECTOR
     UNIMPLEMENTED(WARNING);
@@ -229,8 +229,8 @@
   Method* DecodeMethod(jmethodID mid) const
       LOCKS_EXCLUDED(JavaVMExt::globals_lock,
                      JavaVMExt::weak_globals_lock)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
-    GlobalSynchronization::mutator_lock_->AssertSharedHeld();
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+    Locks::mutator_lock_->AssertSharedHeld();
     DCHECK_EQ(thread_state_, kRunnable);  // Don't work with raw objects in non-runnable states.
 #ifdef MOVING_GARBAGE_COLLECTOR
     // TODO: we should make these unique weak globals if Method instances can ever move.
@@ -240,8 +240,8 @@
   }
 
   jmethodID EncodeMethod(Method* method) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
-    GlobalSynchronization::mutator_lock_->AssertSharedHeld();
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+    Locks::mutator_lock_->AssertSharedHeld();
     DCHECK_EQ(thread_state_, kRunnable);  // Don't work with raw objects in non-runnable states.
 #ifdef MOVING_GARBAGE_COLLECTOR
     UNIMPLEMENTED(WARNING);
@@ -281,20 +281,20 @@
 class ScopedObjectAccess : public ScopedObjectAccessUnchecked {
  public:
   explicit ScopedObjectAccess(JNIEnv* env)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_)
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      SHARED_LOCK_FUNCTION(Locks::mutator_lock_)
       : ScopedObjectAccessUnchecked(env) {
-    GlobalSynchronization::mutator_lock_->AssertSharedHeld();
+    Locks::mutator_lock_->AssertSharedHeld();
   }
 
   explicit ScopedObjectAccess(Thread* self)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_)
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      SHARED_LOCK_FUNCTION(Locks::mutator_lock_)
       : ScopedObjectAccessUnchecked(self) {
-    GlobalSynchronization::mutator_lock_->AssertSharedHeld();
+    Locks::mutator_lock_->AssertSharedHeld();
   }
 
-  ~ScopedObjectAccess() UNLOCK_FUNCTION(GlobalSynchronization::mutator_lock_) {
+  ~ScopedObjectAccess() UNLOCK_FUNCTION(Locks::mutator_lock_) {
     // Base class will release share of lock. Invoked after this destructor.
   }
 
@@ -303,7 +303,7 @@
   //       routines operating with just a VM are sound, they are not, but when you have just a VM
   //       you cannot call the unsound routines.
   explicit ScopedObjectAccess(JavaVM* vm)
-      SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCK_FUNCTION(Locks::mutator_lock_)
       : ScopedObjectAccessUnchecked(vm) {}
 
   friend class ScopedCheck;
diff --git a/src/signal_catcher.cc b/src/signal_catcher.cc
index 156aec6..229edf6 100644
--- a/src/signal_catcher.cc
+++ b/src/signal_catcher.cc
@@ -122,12 +122,12 @@
 
   // We should exclusively hold the mutator lock, set state to Runnable without a pending
   // suspension to avoid giving away or trying re-acquire the mutator lock.
-  GlobalSynchronization::mutator_lock_->AssertExclusiveHeld();
+  Locks::mutator_lock_->AssertExclusiveHeld();
   Thread* self = Thread::Current();
   ThreadState old_state;
   int suspend_count;
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     suspend_count = self->GetSuspendCount();
     if (suspend_count != 0) {
       CHECK_EQ(suspend_count, 1);
@@ -155,7 +155,7 @@
 
   os << "----- end " << getpid() << " -----\n";
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     self->SetState(old_state);
     if (suspend_count != 0) {
       self->ModifySuspendCount(+1, false);
diff --git a/src/signal_catcher.h b/src/signal_catcher.h
index 11a2c09..e8ac812 100644
--- a/src/signal_catcher.h
+++ b/src/signal_catcher.h
@@ -35,9 +35,9 @@
   explicit SignalCatcher(const std::string& stack_trace_file);
   ~SignalCatcher();
 
-  void HandleSigQuit() LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_,
-                                      GlobalSynchronization::thread_list_lock_,
-                                      GlobalSynchronization::thread_suspend_count_lock_);
+  void HandleSigQuit() LOCKS_EXCLUDED(Locks::mutator_lock_,
+                                      Locks::thread_list_lock_,
+                                      Locks::thread_suspend_count_lock_);
 
 
  private:
diff --git a/src/space.h b/src/space.h
index 79d5ad4..3132911 100644
--- a/src/space.h
+++ b/src/space.h
@@ -53,7 +53,7 @@
 
   // create a Space from an image file. cannot be used for future allocation or collected.
   static ImageSpace* CreateImageSpace(const std::string& image)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   virtual ~Space() {}
 
@@ -282,7 +282,7 @@
 
   // Mark the objects defined in this space in the given live bitmap
   void RecordImageAllocations(SpaceBitmap* live_bitmap) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   virtual bool IsAllocSpace() const {
     return false;
diff --git a/src/space_bitmap.cc b/src/space_bitmap.cc
index 439e637..7a4c48d 100644
--- a/src/space_bitmap.cc
+++ b/src/space_bitmap.cc
@@ -174,7 +174,7 @@
 // class.
 static void WalkInstanceFields(SpaceBitmap* visited, SpaceBitmap::Callback* callback, Object* obj,
                                Class* klass, void* arg)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   // Visit fields of parent classes first.
   Class* super = klass->GetSuperClass();
   if (super != NULL) {
@@ -199,7 +199,7 @@
 // For an unvisited object, visit it then all its children found via fields.
 static void WalkFieldsInOrder(SpaceBitmap* visited, SpaceBitmap::Callback* callback, Object* obj,
                               void* arg)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   if (visited->Test(obj)) {
     return;
   }
diff --git a/src/space_bitmap.h b/src/space_bitmap.h
index db1a5eb..02f0034 100644
--- a/src/space_bitmap.h
+++ b/src/space_bitmap.h
@@ -109,7 +109,7 @@
   template <typename Visitor, typename FingerVisitor>
   void VisitMarkedRange(uintptr_t visit_begin, uintptr_t visit_end,
                         const Visitor& visitor, const FingerVisitor& finger_visitor) const
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_) {
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
     DCHECK_LT(visit_begin, visit_end);
 
     const size_t word_span = kAlignment * kBitsPerWord; // Equals IndexToOffset(1).
@@ -177,11 +177,11 @@
   }
 
   void Walk(Callback* callback, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
 
   void InOrderWalk(Callback* callback, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::heap_bitmap_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void SweepWalk(const SpaceBitmap& live,
                         const SpaceBitmap& mark,
diff --git a/src/stack.h b/src/stack.h
index 578c631..60218b1 100644
--- a/src/stack.h
+++ b/src/stack.h
@@ -215,7 +215,7 @@
  protected:
   StackVisitor(const ManagedStack* stack, const std::vector<TraceStackFrame>* trace_stack,
                Context* context)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : stack_start_(stack), trace_stack_(trace_stack), cur_shadow_frame_(NULL),
         cur_quick_frame_(NULL), cur_quick_frame_pc_(0), num_frames_(0), cur_depth_(0),
         context_(context) {}
@@ -224,10 +224,10 @@
   virtual ~StackVisitor() {}
 
   // Return 'true' if we should continue to visit more frames, 'false' to stop.
-  virtual bool VisitFrame() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) = 0;
+  virtual bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) = 0;
 
   void WalkStack(bool include_transitions = false)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Method* GetMethod() const {
     if (cur_shadow_frame_ != NULL) {
@@ -255,19 +255,19 @@
     return *reinterpret_cast<uintptr_t*>(save_addr);
   }
 
-  uint32_t GetDexPc() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  uint32_t GetDexPc() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Returns the height of the stack in the managed stack frames, including transitions.
-  size_t GetFrameHeight() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t GetFrameHeight() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetNumFrames() - cur_depth_;
   }
 
   // Returns a frame ID for JDWP use, starting from 1.
-  size_t GetFrameId() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t GetFrameId() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return GetFrameHeight() + 1;
   }
 
-  size_t GetNumFrames() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  size_t GetNumFrames() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (num_frames_ == 0) {
       num_frames_ = ComputeNumFrames();
     }
@@ -275,10 +275,10 @@
   }
 
   uint32_t GetVReg(Method* m, int vreg) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void SetVReg(Method* m, int vreg, uint32_t new_value)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   uintptr_t GetGPR(uint32_t reg) const;
 
@@ -370,13 +370,13 @@
   }
 
  private:
-  size_t ComputeNumFrames() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  size_t ComputeNumFrames() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   TraceStackFrame GetTraceStackFrame(uint32_t depth) const {
     return trace_stack_->at(trace_stack_->size() - depth - 1);
   }
 
-  void SanityCheckFrame() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void SanityCheckFrame() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   const ManagedStack* const stack_start_;
   const std::vector<TraceStackFrame>* const trace_stack_;
diff --git a/src/thread.cc b/src/thread.cc
index c2bb1a6..57f9905 100644
--- a/src/thread.cc
+++ b/src/thread.cc
@@ -127,7 +127,7 @@
 
 static void SetVmData(const ScopedObjectAccess& soa, Object* managed_thread,
                       Thread* native_thread)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Field* f = soa.DecodeField(WellKnownClasses::java_lang_Thread_vmData);
   f->SetInt(managed_thread, reinterpret_cast<uintptr_t>(native_thread));
 }
@@ -137,9 +137,9 @@
   Thread* result = reinterpret_cast<Thread*>(static_cast<uintptr_t>(f->GetInt(thread_peer)));
   // Sanity check that if we have a result it is either suspended or we hold the thread_list_lock_
   // to stop it from going away.
-  MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+  MutexLock mu(*Locks::thread_suspend_count_lock_);
   if (result != NULL && !result->IsSuspended()) {
-    GlobalSynchronization::thread_list_lock_->AssertHeld();
+    Locks::thread_list_lock_->AssertHeld();
   }
   return result;
 }
@@ -285,7 +285,7 @@
   self->Init();
 
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_NE(self->GetState(), kRunnable);
     self->SetState(kNative);
   }
@@ -444,13 +444,13 @@
 
 // Attempt to rectify locks so that we dump thread list with required locks before exiting.
 static void UnsafeLogFatalForSuspendCount(Thread* self) NO_THREAD_SAFETY_ANALYSIS {
-  GlobalSynchronization::thread_suspend_count_lock_->Unlock();
-  GlobalSynchronization::mutator_lock_->SharedTryLock();
-  if (!GlobalSynchronization::mutator_lock_->IsSharedHeld()) {
+  Locks::thread_suspend_count_lock_->Unlock();
+  Locks::mutator_lock_->SharedTryLock();
+  if (!Locks::mutator_lock_->IsSharedHeld()) {
     LOG(WARNING) << "Dumping thread list without holding mutator_lock_";
   }
-  GlobalSynchronization::thread_list_lock_->TryLock();
-  if (!GlobalSynchronization::thread_list_lock_->IsExclusiveHeld()) {
+  Locks::thread_list_lock_->TryLock();
+  if (!Locks::thread_list_lock_->IsExclusiveHeld()) {
     LOG(WARNING) << "Dumping thread list without holding thread_list_lock_";
   }
   std::ostringstream ss;
@@ -462,7 +462,7 @@
   DCHECK(delta == -1 || delta == +1 || delta == -debug_suspend_count_)
       << delta << " " << debug_suspend_count_ << " " << this;
   DCHECK_GE(suspend_count_, debug_suspend_count_) << this;
-  GlobalSynchronization::thread_suspend_count_lock_->AssertHeld();
+  Locks::thread_suspend_count_lock_->AssertHeld();
 
   if (delta == -1 && suspend_count_ <= 0) {
     // This is expected if you attach a thread during a GC.
@@ -494,7 +494,7 @@
   ThreadState old_state = SetStateUnsafe(new_state);
   CHECK_EQ(old_state, kRunnable);
   // Release share on mutator_lock_.
-  GlobalSynchronization::mutator_lock_->SharedUnlock();
+  Locks::mutator_lock_->SharedUnlock();
 }
 
 ThreadState Thread::TransitionFromSuspendedToRunnable() {
@@ -506,24 +506,24 @@
     // may occur is covered by the second check after we acquire a share of the mutator_lock_.
     if (GetSuspendCountUnsafe() > 0) {
       // Wait while our suspend count is non-zero.
-      MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
-      GlobalSynchronization::mutator_lock_->AssertNotHeld();  // Otherwise we starve GC..
+      MutexLock mu(*Locks::thread_suspend_count_lock_);
+      Locks::mutator_lock_->AssertNotHeld();  // Otherwise we starve GC..
       while (GetSuspendCount() != 0) {
         // Re-check when Thread::resume_cond_ is notified.
-        Thread::resume_cond_->Wait(*GlobalSynchronization::thread_suspend_count_lock_);
+        Thread::resume_cond_->Wait(*Locks::thread_suspend_count_lock_);
       }
     }
     // Re-acquire shared mutator_lock_ access.
-    GlobalSynchronization::mutator_lock_->SharedLock();
+    Locks::mutator_lock_->SharedLock();
     // Holding the mutator_lock_, synchronize with any thread trying to raise the suspend count
     // and change state to Runnable if no suspend is pending.
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     if (GetSuspendCount() == 0) {
       SetState(kRunnable);
       done = true;
     } else {
       // Release shared mutator_lock_ access and try again.
-      GlobalSynchronization::mutator_lock_->SharedUnlock();
+      Locks::mutator_lock_->SharedUnlock();
     }
   } while (!done);
   return old_state;
@@ -539,14 +539,14 @@
     Thread* thread;
     {
       ScopedObjectAccess soa(Thread::Current());
-      MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+      MutexLock mu(*Locks::thread_list_lock_);
       thread = Thread::FromManagedThread(soa, peer);
       if (thread == NULL) {
         LOG(WARNING) << "No such thread for suspend: " << peer;
         return NULL;
       }
       {
-        MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+        MutexLock mu(*Locks::thread_suspend_count_lock_);
         if (request_suspension) {
           thread->ModifySuspendCount(+1, true /* for_debugger */);
           request_suspension = false;
@@ -629,7 +629,7 @@
     if (is_daemon) {
       os << " daemon";
     }
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     os << " prio=" << priority
        << " tid=" << thread->GetThinLockId()
        << " " << thread->GetState() << "\n";
@@ -640,7 +640,7 @@
   }
 
   if (thread != NULL) {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     os << "  | group=\"" << group_name << "\""
        << " sCount=" << thread->suspend_count_
        << " dsCount=" << thread->debug_suspend_count_
@@ -690,7 +690,7 @@
 
 struct StackDumpVisitor : public StackVisitor {
   StackDumpVisitor(std::ostream& os, const Thread* thread, Context* context, bool can_allocate)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : StackVisitor(thread->GetManagedStack(), thread->GetTraceStack(), context),
         os(os), thread(thread), can_allocate(can_allocate),
         last_method(NULL), last_line_number(0), repetition_count(0), frame_count(0) {
@@ -702,7 +702,7 @@
     }
   }
 
-  bool VisitFrame() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* m = GetMethod();
     if (m->IsRuntimeMethod()) {
       return true;
@@ -762,7 +762,7 @@
   // If we're currently in native code, dump that stack before dumping the managed stack.
   ThreadState state;
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     state = GetState();
   }
   if (state == kNative) {
@@ -787,7 +787,7 @@
 
 void Thread::Startup() {
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);  // Keep GCC happy.
+    MutexLock mu(*Locks::thread_suspend_count_lock_);  // Keep GCC happy.
     resume_cond_ = new ConditionVariable("Thread resumption condition variable");
   }
 
@@ -920,7 +920,7 @@
   jni_env_ = NULL;
 
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_NE(GetState(), kRunnable);
     SetState(kTerminated);
   }
@@ -1078,11 +1078,11 @@
  public:
   CountStackDepthVisitor(const ManagedStack* stack,
                          const std::vector<TraceStackFrame>* trace_stack)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : StackVisitor(stack, trace_stack, NULL),
         depth_(0), skip_depth_(0), skipping_(true) {}
 
-  bool VisitFrame() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     // We want to skip frames up to and including the exception's constructor.
     // Note we also skip the frame if it doesn't have a method (namely the callee
     // save frame)
@@ -1124,7 +1124,7 @@
         skip_depth_(skip_depth), count_(0), dex_pc_trace_(NULL), method_trace_(NULL) {}
 
   bool Init(int depth, const ScopedObjectAccess& soa)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     // Allocate method trace with an extra slot that will hold the PC trace
     SirtRef<ObjectArray<Object> >
       method_trace(Runtime::Current()->GetClassLinker()->AllocObjectArray<Object>(depth + 1));
@@ -1153,7 +1153,7 @@
     }
   }
 
-  bool VisitFrame() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (method_trace_ == NULL || dex_pc_trace_ == NULL) {
       return true; // We're probably trying to fillInStackTrace for an OutOfMemoryError.
     }
@@ -1513,7 +1513,7 @@
 class CatchBlockStackVisitor : public StackVisitor {
  public:
   CatchBlockStackVisitor(Thread* self, Throwable* exception)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : StackVisitor(self->GetManagedStack(), self->GetTraceStack(), self->GetLongJumpContext()),
         self_(self), exception_(exception), to_find_(exception->GetClass()), throw_method_(NULL),
         throw_frame_id_(0), throw_dex_pc_(0), handler_quick_frame_(NULL),
@@ -1527,8 +1527,8 @@
     LOG(FATAL) << "UNREACHABLE";  // Expected to take long jump.
   }
 
-  bool VisitFrame() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* method = GetMethod();
     if (method == NULL) {
       // This is the upcall, we remember the frame and last pc so that we may long jump to them.
@@ -1570,7 +1570,7 @@
     return true;  // Continue stack walk.
   }
 
-  void DoLongJump() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  void DoLongJump() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     Method* catch_method = *handler_quick_frame_;
     Dbg::PostException(self_, throw_frame_id_, throw_method_, throw_dex_pc_,
                        catch_method, handler_dex_pc_, exception_);
@@ -1650,10 +1650,10 @@
   struct CurrentMethodVisitor : public StackVisitor {
     CurrentMethodVisitor(const ManagedStack* stack,
                          const std::vector<TraceStackFrame>* trace_stack)
-        SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
         : StackVisitor(stack, trace_stack, NULL), method_(NULL), dex_pc_(0), frame_id_(0) {}
 
-    virtual bool VisitFrame() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    virtual bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
       Method* m = GetMethod();
       if (m->IsRuntimeMethod()) {
         // Continue if this is a runtime method.
@@ -1691,10 +1691,10 @@
  public:
   ReferenceMapVisitor(const ManagedStack* stack, const std::vector<TraceStackFrame>* trace_stack,
                       Context* context, Heap::RootVisitor* root_visitor, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
       : StackVisitor(stack, trace_stack, context), root_visitor_(root_visitor), arg_(arg) {}
 
-  bool VisitFrame() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (false) {
       LOG(INFO) << "Visiting stack roots in " << PrettyMethod(GetMethod())
           << StringPrintf("@ PC:%04x", GetDexPc());
diff --git a/src/thread.h b/src/thread.h
index 8dce414..9355dca 100644
--- a/src/thread.h
+++ b/src/thread.h
@@ -121,11 +121,11 @@
   }
 
   static Thread* FromManagedThread(const ScopedObjectAccessUnchecked& ts, Object* thread_peer)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static Thread* FromManagedThread(const ScopedObjectAccessUnchecked& ts, jobject thread)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Translates 172 to pAllocArrayFromCode and so on.
   static void DumpThreadOffset(std::ostream& os, uint32_t offset, size_t size_of_pointers);
@@ -135,79 +135,79 @@
 
   // Dumps the detailed thread state and the thread stack (used for SIGQUIT).
   void Dump(std::ostream& os) const
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Dumps the SIGQUIT per-thread header. 'thread' can be NULL for a non-attached thread, in which
   // case we use 'tid' to identify the thread, and we'll include as much information as we can.
   static void DumpState(std::ostream& os, const Thread* thread, pid_t tid)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_);
 
   ThreadState GetState() const
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_suspend_count_lock_) {
-    GlobalSynchronization::thread_suspend_count_lock_->AssertHeld();
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_suspend_count_lock_) {
+    Locks::thread_suspend_count_lock_->AssertHeld();
     return state_;
   }
 
   ThreadState SetState(ThreadState new_state)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_suspend_count_lock_) {
-    GlobalSynchronization::thread_suspend_count_lock_->AssertHeld();
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_suspend_count_lock_) {
+    Locks::thread_suspend_count_lock_->AssertHeld();
     ThreadState old_state = state_;
     if (new_state == kRunnable) {
       // Sanity, should never become runnable with a pending suspension and should always hold
       // share of mutator_lock_.
       CHECK_EQ(GetSuspendCount(), 0);
-      GlobalSynchronization::mutator_lock_->AssertSharedHeld();
+      Locks::mutator_lock_->AssertSharedHeld();
     }
     state_ = new_state;
     return old_state;
   }
 
   int GetSuspendCount() const
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_suspend_count_lock_) {
-    GlobalSynchronization::thread_suspend_count_lock_->AssertHeld();
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_suspend_count_lock_) {
+    Locks::thread_suspend_count_lock_->AssertHeld();
     return suspend_count_;
   }
 
   int GetDebugSuspendCount() const
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_suspend_count_lock_) {
-    GlobalSynchronization::thread_suspend_count_lock_->AssertHeld();
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_suspend_count_lock_) {
+    Locks::thread_suspend_count_lock_->AssertHeld();
     return debug_suspend_count_;
   }
 
   bool IsSuspended() const
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_suspend_count_lock_) {
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_suspend_count_lock_) {
     int suspend_count = GetSuspendCount();
     return suspend_count != 0 && GetState() != kRunnable;
   }
 
   void ModifySuspendCount(int delta, bool for_debugger)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_suspend_count_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_suspend_count_lock_);
 
   // Called when thread detected that the thread_suspend_count_ was non-zero. Gives up share of
   // mutator_lock_ and waits until it is resumed and thread_suspend_count_ is zero.
   void FullSuspendCheck()
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Transition from non-runnable to runnable state acquiring share on mutator_lock_.
   ThreadState TransitionFromSuspendedToRunnable()
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      SHARED_LOCK_FUNCTION(Locks::mutator_lock_);
 
   // Transition from runnable into a state where mutator privileges are denied. Releases share of
   // mutator lock.
   void TransitionFromRunnableToSuspended(ThreadState new_state)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      UNLOCK_FUNCTION(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      UNLOCK_FUNCTION(Locks::mutator_lock_);
 
   // Wait for a debugger suspension on the thread associated with the given peer. Returns the
   // thread on success, else NULL. If the thread should be suspended then request_suspension should
   // be true on entry. If the suspension times out then *timeout is set to true.
   static Thread* SuspendForDebugger(jobject peer,  bool request_suspension, bool* timeout)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_,
-                     GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_,
+                     Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_);
 
   // Once called thread suspension will cause an assertion failure.
 #ifndef NDEBUG
@@ -286,16 +286,16 @@
 
   // Returns the java.lang.Thread's name, or NULL if this Thread* doesn't have a peer.
   String* GetThreadName(const ScopedObjectAccessUnchecked& ts) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Sets 'name' to the java.lang.Thread's name. This requires no transition to managed code,
   // allocation, or locking.
   void GetThreadName(std::string& name) const;
 
   // Sets the thread's name.
-  void SetThreadName(const char* name) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void SetThreadName(const char* name) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  Object* GetPeer() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  Object* GetPeer() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return peer_;
   }
 
@@ -304,7 +304,7 @@
   }
 
   Object* GetThreadGroup(const ScopedObjectAccessUnchecked& ts) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   RuntimeStats* GetStats() {
     return &stats_;
@@ -316,7 +316,7 @@
     return exception_ != NULL;
   }
 
-  Throwable* GetException() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  Throwable* GetException() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(CanAccessDirectReferences());
     return exception_;
   }
@@ -324,7 +324,7 @@
   void AssertNoPendingException() const;
 
   void SetException(Throwable* new_exception)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(CanAccessDirectReferences());
     CHECK(new_exception != NULL);
     // TODO: CHECK(exception_ == NULL);
@@ -336,7 +336,7 @@
   }
 
   // Find catch block and perform long jump to appropriate exception handle
-  void DeliverException() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void DeliverException() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   Context* GetLongJumpContext();
   void ReleaseLongJumpContext(Context* context) {
@@ -345,7 +345,7 @@
   }
 
   Method* GetCurrentMethod(uint32_t* dex_pc = NULL, size_t* frame_id = NULL) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void SetTopOfStack(void* stack, uintptr_t pc) {
     Method** top_method = reinterpret_cast<Method**>(stack);
@@ -359,24 +359,24 @@
 
   // If 'msg' is NULL, no detail message is set.
   void ThrowNewException(const char* exception_class_descriptor, const char* msg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // If 'msg' is NULL, no detail message is set. An exception must be pending, and will be
   // used as the new exception's cause.
   void ThrowNewWrappedException(const char* exception_class_descriptor, const char* msg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void ThrowNewExceptionF(const char* exception_class_descriptor, const char* fmt, ...)
       __attribute__((format(printf, 3, 4)))
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void ThrowNewExceptionV(const char* exception_class_descriptor, const char* fmt, va_list ap)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // OutOfMemoryError is special, because we need to pre-allocate an instance.
   // Only the GC should call this.
   void ThrowOutOfMemoryError(const char* msg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   //QuickFrameIterator FindExceptionHandler(void* throw_pc, void** handler_pc);
 
@@ -398,7 +398,7 @@
   Object* DecodeJObject(jobject obj)
       LOCKS_EXCLUDED(JavaVMExt::globals_lock,
                      JavaVMExt::weak_globals_lock)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Implements java.lang.Thread.interrupted.
   bool Interrupted() {
@@ -429,7 +429,7 @@
   }
 
   ClassLoader* GetClassLoaderOverride()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     DCHECK(CanAccessDirectReferences());
     return class_loader_override_;
   }
@@ -441,7 +441,7 @@
   // Create the internal representation of a stack trace, that is more time
   // and space efficient to compute than the StackTraceElement[]
   jobject CreateInternalStackTrace(const ScopedObjectAccess& soa) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Convert an internal stack trace representation (returned by CreateInternalStackTrace) to a
   // StackTraceElement[]. If output_array is NULL, a new array is created, otherwise as many
@@ -451,12 +451,12 @@
       jobjectArray output_array = NULL, int* stack_depth = NULL);
 
   void VisitRoots(Heap::RootVisitor* visitor, void* arg)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 #if VERIFY_OBJECT_ENABLED
-  void VerifyStack() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void VerifyStack() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 #else
-  void VerifyStack() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_){}
+  void VerifyStack() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_){}
 #endif
 
   //
@@ -493,7 +493,7 @@
   }
 
   // Set the stack end to that to be used during a stack overflow
-  void SetStackEndForStackOverflow() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void SetStackEndForStackOverflow() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Set the stack end to that to be used during regular execution
   void ResetDefaultStackEnd() {
@@ -608,8 +608,8 @@
   typedef uint32_t bool32_t;
 
   explicit Thread(bool daemon);
-  ~Thread() LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_,
-                           GlobalSynchronization::thread_suspend_count_lock_);
+  ~Thread() LOCKS_EXCLUDED(Locks::mutator_lock_,
+                           Locks::thread_suspend_count_lock_);
   void Destroy();
   friend class ThreadList;  // For ~Thread and Destroy.
 
@@ -640,20 +640,20 @@
 
   void DumpState(std::ostream& os) const;
   void DumpStack(std::ostream& os) const
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Out-of-line conveniences for debugging in gdb.
   static Thread* CurrentFromGdb(); // Like Thread::Current.
   // Like Thread::Dump(std::cerr).
-  void DumpFromGdb() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void DumpFromGdb() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void* CreateCallback(void* arg);
 
   void HandleUncaughtExceptions(const ScopedObjectAccess& soa)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void RemoveFromThreadGroup(const ScopedObjectAccess& soa)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void Init();
   void InitCardTable();
@@ -677,13 +677,13 @@
   // Used to notify threads that they should attempt to resume, they will suspend again if
   // their suspend count is > 0.
   static ConditionVariable* resume_cond_
-      GUARDED_BY(GlobalSynchronization::thread_suspend_count_lock_);
+      GUARDED_BY(Locks::thread_suspend_count_lock_);
 
   // --- Frequently accessed fields first for short offsets ---
 
   // A non-zero value is used to tell the current thread to enter a safe point
   // at the next poll.
-  int suspend_count_ GUARDED_BY(GlobalSynchronization::thread_suspend_count_lock_);
+  int suspend_count_ GUARDED_BY(Locks::thread_suspend_count_lock_);
 
   // The biased card table, see CardTable for details
   byte* card_table_;
@@ -706,7 +706,7 @@
   // is hard. This field can be read off of Thread::Current to give the address.
   Thread* self_;
 
-  volatile ThreadState state_ GUARDED_BY(GlobalSynchronization::thread_suspend_count_lock_);
+  volatile ThreadState state_ GUARDED_BY(Locks::thread_suspend_count_lock_);
 
   // Our managed peer (an instance of java.lang.Thread).
   Object* peer_;
@@ -760,7 +760,7 @@
 
   // How much of 'suspend_count_' is by request of the debugger, used to set things right
   // when the debugger detaches. Must be <= suspend_count_.
-  int debug_suspend_count_ GUARDED_BY(GlobalSynchronization::thread_suspend_count_lock_);
+  int debug_suspend_count_ GUARDED_BY(Locks::thread_suspend_count_lock_);
 
   // JDWP invoke-during-breakpoint support.
   DebugInvokeReq* debug_invoke_req_;
diff --git a/src/thread_list.cc b/src/thread_list.cc
index 6008e16..c1db387 100644
--- a/src/thread_list.cc
+++ b/src/thread_list.cc
@@ -61,12 +61,12 @@
 }
 
 pid_t ThreadList::GetLockOwner() {
-  return GlobalSynchronization::thread_list_lock_->GetExclusiveOwnerTid();
+  return Locks::thread_list_lock_->GetExclusiveOwnerTid();
 }
 
 void ThreadList::DumpForSigQuit(std::ostream& os) {
   {
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
     DumpLocked(os);
   }
   DumpUnattachedThreads(os);
@@ -97,7 +97,7 @@
     if (!*end) {
       bool contains;
       {
-        MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+        MutexLock mu(*Locks::thread_list_lock_);
         contains = Contains(tid);
       }
       if (!contains) {
@@ -109,7 +109,7 @@
 }
 
 void ThreadList::DumpLocked(std::ostream& os) {
-  GlobalSynchronization::thread_list_lock_->AssertHeld();
+  Locks::thread_list_lock_->AssertHeld();
   os << "DALVIK THREADS (" << list_.size() << "):\n";
   for (It it = list_.begin(), end = list_.end(); it != end; ++it) {
     (*it)->Dump(os);
@@ -118,8 +118,8 @@
 }
 
 void ThreadList::AssertThreadsAreSuspended() {
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
-  MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
+  MutexLock mu2(*Locks::thread_suspend_count_lock_);
   for (It it = list_.begin(), end = list_.end(); it != end; ++it) {
     Thread* thread = *it;
     CHECK_NE(thread->GetState(), kRunnable);
@@ -134,12 +134,12 @@
   ss << "Thread suspend timeout\n";
   runtime->DumpLockHolders(ss);
   ss << "\n";
-  GlobalSynchronization::mutator_lock_->SharedTryLock();
-  if (!GlobalSynchronization::mutator_lock_->IsSharedHeld()) {
+  Locks::mutator_lock_->SharedTryLock();
+  if (!Locks::mutator_lock_->IsSharedHeld()) {
     LOG(WARNING) << "Dumping thread list without holding mutator_lock_";
   }
-  GlobalSynchronization::thread_list_lock_->TryLock();
-  if (!GlobalSynchronization::thread_list_lock_->IsExclusiveHeld()) {
+  Locks::thread_list_lock_->TryLock();
+  if (!Locks::thread_list_lock_->IsExclusiveHeld()) {
     LOG(WARNING) << "Dumping thread list without holding thread_list_lock_";
   }
   runtime->GetThreadList()->DumpLocked(ss);
@@ -153,16 +153,16 @@
   VLOG(threads) << *self << " SuspendAll starting...";
 
   if (kIsDebugBuild) {
-    GlobalSynchronization::mutator_lock_->AssertNotHeld();
-    GlobalSynchronization::thread_list_lock_->AssertNotHeld();
-    GlobalSynchronization::thread_suspend_count_lock_->AssertNotHeld();
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    Locks::mutator_lock_->AssertNotHeld();
+    Locks::thread_list_lock_->AssertNotHeld();
+    Locks::thread_suspend_count_lock_->AssertNotHeld();
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     CHECK_NE(self->GetState(), kRunnable);
   }
   {
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
     {
-      MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+      MutexLock mu2(*Locks::thread_suspend_count_lock_);
       // Update global suspend all state for attaching threads.
       ++suspend_all_count_;
       // Increment everybody's suspend count (except our own).
@@ -183,11 +183,11 @@
   timespec timeout;
   clock_gettime(CLOCK_REALTIME, &timeout);
   timeout.tv_sec += 30;
-  if (UNLIKELY(!GlobalSynchronization::mutator_lock_->ExclusiveLockWithTimeout(timeout))) {
+  if (UNLIKELY(!Locks::mutator_lock_->ExclusiveLockWithTimeout(timeout))) {
     UnsafeLogFatalForThreadSuspendAllTimeout();
   }
 #else
-  GlobalSynchronization::mutator_lock_->ExclusiveLock();
+  Locks::mutator_lock_->ExclusiveLock();
 #endif
 
   // Debug check that all threads are suspended.
@@ -201,8 +201,8 @@
 
   VLOG(threads) << *self << " ResumeAll starting";
   {
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
-    MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
+    MutexLock mu2(*Locks::thread_suspend_count_lock_);
     // Update global suspend all state for attaching threads.
     --suspend_all_count_;
     // Decrement the suspend counts for all threads.
@@ -219,7 +219,7 @@
     VLOG(threads) << *self << " ResumeAll waking others";
     Thread::resume_cond_->Broadcast();
   }
-  GlobalSynchronization::mutator_lock_->ExclusiveUnlock();
+  Locks::mutator_lock_->ExclusiveUnlock();
   VLOG(threads) << *self << " ResumeAll complete";
 }
 
@@ -229,9 +229,9 @@
 
   {
     // To check Contains.
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
     // To check IsSuspended.
-    MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu2(*Locks::thread_suspend_count_lock_);
     CHECK(thread->IsSuspended());
     if (!Contains(thread)) {
       return;
@@ -241,7 +241,7 @@
 
   {
     VLOG(threads) << "Resume(" << *thread << ") waking others";
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     Thread::resume_cond_->Broadcast();
   }
 
@@ -255,9 +255,9 @@
   VLOG(threads) << *self << " SuspendAllForDebugger starting...";
 
   {
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
     {
-      MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+      MutexLock mu(*Locks::thread_suspend_count_lock_);
       // Update global suspend all state for attaching threads.
       ++suspend_all_count_;
       ++debug_suspend_all_count_;
@@ -280,14 +280,14 @@
   timespec timeout;
   clock_gettime(CLOCK_REALTIME, &timeout);
   timeout.tv_sec += 30;
-  if (!GlobalSynchronization::mutator_lock_->ExclusiveLockWithTimeout(timeout)) {
+  if (!Locks::mutator_lock_->ExclusiveLockWithTimeout(timeout)) {
     UnsafeLogFatalForThreadSuspendAllTimeout();
   } else {
-    GlobalSynchronization::mutator_lock_->ExclusiveUnlock();
+    Locks::mutator_lock_->ExclusiveUnlock();
   }
 #else
-  GlobalSynchronization::mutator_lock_->ExclusiveLock();
-  GlobalSynchronization::mutator_lock_->ExclusiveUnlock();
+  Locks::mutator_lock_->ExclusiveLock();
+  Locks::mutator_lock_->ExclusiveUnlock();
 #endif
   AssertThreadsAreSuspended();
 
@@ -305,7 +305,7 @@
   // Collisions with other suspends aren't really interesting. We want
   // to ensure that we're the only one fiddling with the suspend count
   // though.
-  MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+  MutexLock mu(*Locks::thread_suspend_count_lock_);
   self->ModifySuspendCount(+1, true);
 
   // Suspend ourselves.
@@ -319,7 +319,7 @@
   Dbg::ClearWaitForEventThread();
 
   while (self->suspend_count_ != 0) {
-    Thread::resume_cond_->Wait(*GlobalSynchronization::thread_suspend_count_lock_);
+    Thread::resume_cond_->Wait(*Locks::thread_suspend_count_lock_);
     if (self->suspend_count_ != 0) {
       // The condition was signaled but we're still suspended. This
       // can happen if the debugger lets go while a SIGQUIT thread
@@ -340,8 +340,8 @@
   VLOG(threads) << *self << " UndoDebuggerSuspensions starting";
 
   {
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
-    MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
+    MutexLock mu2(*Locks::thread_suspend_count_lock_);
     // Update global suspend all state for attaching threads.
     suspend_all_count_ -= debug_suspend_all_count_;
     debug_suspend_all_count_ = 0;
@@ -356,7 +356,7 @@
   }
 
   {
-    MutexLock mu(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu(*Locks::thread_suspend_count_lock_);
     Thread::resume_cond_->Broadcast();
   }
 
@@ -364,8 +364,8 @@
 }
 
 void ThreadList::WaitForOtherNonDaemonThreadsToExit() {
-  GlobalSynchronization::mutator_lock_->AssertNotHeld();
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  Locks::mutator_lock_->AssertNotHeld();
+  MutexLock mu(*Locks::thread_list_lock_);
   bool all_threads_are_daemons;
   do {
     all_threads_are_daemons = true;
@@ -380,15 +380,15 @@
     }
     if (!all_threads_are_daemons) {
       // Wait for another thread to exit before re-checking.
-      thread_exit_cond_.Wait(*GlobalSynchronization::thread_list_lock_);
+      thread_exit_cond_.Wait(*Locks::thread_list_lock_);
     }
   } while(!all_threads_are_daemons);
 }
 
 void ThreadList::SuspendAllDaemonThreads() {
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   { // Tell all the daemons it's time to suspend.
-    MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+    MutexLock mu2(*Locks::thread_suspend_count_lock_);
     for (It it = list_.begin(), end = list_.end(); it != end; ++it) {
       Thread* thread = *it;
       // This is only run after all non-daemon threads have exited, so the remainder should all be
@@ -406,7 +406,7 @@
     bool all_suspended = true;
     for (It it = list_.begin(), end = list_.end(); it != end; ++it) {
       Thread* thread = *it;
-      MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+      MutexLock mu2(*Locks::thread_suspend_count_lock_);
       if (thread != Thread::Current() && thread->GetState() == kRunnable) {
         if (!have_complained) {
           LOG(WARNING) << "daemon thread not yet suspended: " << *thread;
@@ -432,8 +432,8 @@
 
   // Atomically add self to the thread list and make its thread_suspend_count_ reflect ongoing
   // SuspendAll requests.
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
-  MutexLock mu2(*GlobalSynchronization::thread_suspend_count_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
+  MutexLock mu2(*Locks::thread_suspend_count_lock_);
   self->suspend_count_ = suspend_all_count_;
   self->debug_suspend_count_ = debug_suspend_all_count_;
   CHECK(!Contains(self));
@@ -451,7 +451,7 @@
 
   {
     // Remove this thread from the list.
-    MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+    MutexLock mu(*Locks::thread_list_lock_);
     CHECK(Contains(self));
     list_.remove(self);
   }
@@ -466,7 +466,7 @@
   CHECK_PTHREAD_CALL(pthread_setspecific, (Thread::pthread_key_self_, NULL), "detach self");
 
   // Signal that a thread just detached.
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   thread_exit_cond_.Signal();
 }
 
@@ -477,7 +477,7 @@
 }
 
 void ThreadList::VisitRoots(Heap::RootVisitor* visitor, void* arg) const {
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   for (It it = list_.begin(), end = list_.end(); it != end; ++it) {
     (*it)->VisitRoots(visitor, arg);
   }
diff --git a/src/thread_list.h b/src/thread_list.h
index e5b9114..b80c1a5 100644
--- a/src/thread_list.h
+++ b/src/thread_list.h
@@ -34,57 +34,57 @@
   ~ThreadList();
 
   void DumpForSigQuit(std::ostream& os)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void DumpLocked(std::ostream& os)  // For thread suspend timeout dumps.
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_list_lock_)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   pid_t GetLockOwner(); // For SignalCatcher.
 
   // Thread suspension support.
   void ResumeAll()
-      UNLOCK_FUNCTION(GlobalSynchronization::mutator_lock_)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      UNLOCK_FUNCTION(Locks::mutator_lock_)
+      LOCKS_EXCLUDED(Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_);
   void Resume(Thread* thread, bool for_debugger = false)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_);
 
   // Suspends all threads and gets exclusive access to the mutator_lock_.
   void SuspendAll()
-      EXCLUSIVE_LOCK_FUNCTION(GlobalSynchronization::mutator_lock_)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      EXCLUSIVE_LOCK_FUNCTION(Locks::mutator_lock_)
+      LOCKS_EXCLUDED(Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_);
 
   // Suspends all threads
   void SuspendAllForDebugger()
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_,
-                     GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_,
+                     Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_);
 
   void SuspendSelfForDebugger()
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_);
 
   void UndoDebuggerSuspensions()
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_);
 
   // Iterates over all the threads.
   void ForEach(void (*callback)(Thread*, void*), void* context)
-      EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_list_lock_);
+      EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_);
 
   // Add/remove current thread from list.
   void Register(Thread* self)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_,
-                     GlobalSynchronization::thread_list_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_,
+                     Locks::thread_list_lock_);
   void Unregister(Thread* self)
-      LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_,
-                     GlobalSynchronization::thread_list_lock_);
+      LOCKS_EXCLUDED(Locks::mutator_lock_,
+                     Locks::thread_list_lock_);
 
   void VisitRoots(Heap::RootVisitor* visitor, void* arg) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Return a copy of the thread list.
-  std::list<Thread*> GetList() EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_list_lock_) {
+  std::list<Thread*> GetList() EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_) {
     return list_;
   }
 
@@ -94,35 +94,35 @@
   uint32_t AllocThreadId();
   void ReleaseThreadId(uint32_t id) LOCKS_EXCLUDED(allocated_ids_lock_);
 
-  bool Contains(Thread* thread) EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_list_lock_);
-  bool Contains(pid_t tid) EXCLUSIVE_LOCKS_REQUIRED(GlobalSynchronization::thread_list_lock_);
+  bool Contains(Thread* thread) EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_);
+  bool Contains(pid_t tid) EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_lock_);
 
   void DumpUnattachedThreads(std::ostream& os)
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_);
 
   void SuspendAllDaemonThreads()
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_);
   void WaitForOtherNonDaemonThreadsToExit()
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_);
 
   void AssertThreadsAreSuspended()
-      LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_,
-                     GlobalSynchronization::thread_suspend_count_lock_);
+      LOCKS_EXCLUDED(Locks::thread_list_lock_,
+                     Locks::thread_suspend_count_lock_);
 
   mutable Mutex allocated_ids_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
   std::bitset<kMaxThreadId> allocated_ids_ GUARDED_BY(allocated_ids_lock_);
 
   // The actual list of all threads.
-  std::list<Thread*> list_ GUARDED_BY(GlobalSynchronization::thread_list_lock_);
+  std::list<Thread*> list_ GUARDED_BY(Locks::thread_list_lock_);
 
   // Ongoing suspend all requests, used to ensure threads added to list_ respect SuspendAll.
-  int suspend_all_count_ GUARDED_BY(GlobalSynchronization::thread_suspend_count_lock_);
-  int debug_suspend_all_count_ GUARDED_BY(GlobalSynchronization::thread_suspend_count_lock_);
+  int suspend_all_count_ GUARDED_BY(Locks::thread_suspend_count_lock_);
+  int debug_suspend_all_count_ GUARDED_BY(Locks::thread_suspend_count_lock_);
 
   // Signaled when threads terminate. Used to determine when all non-daemons have terminated.
-  ConditionVariable thread_exit_cond_ GUARDED_BY(GlobalSynchronization::thread_list_lock_);
+  ConditionVariable thread_exit_cond_ GUARDED_BY(Locks::thread_list_lock_);
 
   friend class Thread;
 
diff --git a/src/trace.cc b/src/trace.cc
index 5ac7e3d..e4bc836 100644
--- a/src/trace.cc
+++ b/src/trace.cc
@@ -159,7 +159,7 @@
 }
 
 static bool InstallStubsClassVisitor(Class* klass, void*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Trace* tracer = Runtime::Current()->GetTracer();
   for (size_t i = 0; i < klass->NumDirectMethods(); i++) {
     Method* method = klass->GetDirectMethod(i);
@@ -178,7 +178,7 @@
 }
 
 static bool UninstallStubsClassVisitor(Class* klass, void*)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   Trace* tracer = Runtime::Current()->GetTracer();
   for (size_t i = 0; i < klass->NumDirectMethods(); i++) {
     Method* method = klass->GetDirectMethod(i);
@@ -489,8 +489,8 @@
 }
 
 void Trace::DumpThreadList(std::ostream& os) {
-  GlobalSynchronization::thread_list_lock_->AssertNotHeld();
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  Locks::thread_list_lock_->AssertNotHeld();
+  MutexLock mu(*Locks::thread_list_lock_);
   Runtime::Current()->GetThreadList()->ForEach(DumpThread, &os);
 }
 
@@ -499,9 +499,9 @@
 }
 
 void Trace::UninstallStubs() {
-  GlobalSynchronization::thread_list_lock_->AssertNotHeld();
+  Locks::thread_list_lock_->AssertNotHeld();
   Runtime::Current()->GetClassLinker()->VisitClasses(UninstallStubsClassVisitor, NULL);
-  MutexLock mu(*GlobalSynchronization::thread_list_lock_);
+  MutexLock mu(*Locks::thread_list_lock_);
   Runtime::Current()->GetThreadList()->ForEach(TraceRestoreStack, NULL);
 }
 
diff --git a/src/trace.h b/src/trace.h
index c60ae15..9c64347 100644
--- a/src/trace.h
+++ b/src/trace.h
@@ -83,18 +83,18 @@
   explicit Trace(File* trace_file, int buffer_size, int flags);
 
   void BeginTracing();
-  void FinishTracing() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void FinishTracing() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Replaces code of each method with a pointer to a stub for method tracing.
   void InstallStubs();
 
   // Restores original code for each method and fixes the return values of each thread's stack.
-  void UninstallStubs() LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_);
+  void UninstallStubs() LOCKS_EXCLUDED(Locks::thread_list_lock_);
 
   // Methods to output traced methods and threads.
   void GetVisitedMethods(size_t end_offset);
-  void DumpMethodList(std::ostream& os) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
-  void DumpThreadList(std::ostream& os) LOCKS_EXCLUDED(GlobalSynchronization::thread_list_lock_);
+  void DumpMethodList(std::ostream& os) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+  void DumpThreadList(std::ostream& os) LOCKS_EXCLUDED(Locks::thread_list_lock_);
 
   // Maps a method to its original code pointer.
   SafeMap<const Method*, const void*> saved_code_map_;
diff --git a/src/utf.h b/src/utf.h
index dd5791c..1d4101f 100644
--- a/src/utf.h
+++ b/src/utf.h
@@ -65,7 +65,7 @@
  * The java.lang.String hashCode() algorithm.
  */
 int32_t ComputeUtf16Hash(const CharArray* chars, int32_t offset, size_t char_count)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 int32_t ComputeUtf16Hash(const uint16_t* chars, size_t char_count);
 
 /*
diff --git a/src/utils.h b/src/utils.h
index 2846dad..335a669 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -168,18 +168,18 @@
 std::string PrettyDescriptor(const std::string& descriptor);
 std::string PrettyDescriptor(Primitive::Type type);
 std::string PrettyDescriptor(const Class* klass)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 // Returns a human-readable signature for 'f'. Something like "a.b.C.f" or
 // "int a.b.C.f" (depending on the value of 'with_type').
 std::string PrettyField(const Field* f, bool with_type = true)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 std::string PrettyField(uint32_t field_idx, const DexFile& dex_file, bool with_type = true);
 
 // Returns a human-readable signature for 'm'. Something like "a.b.C.m" or
 // "a.b.C.m(II)V" (depending on the value of 'with_signature').
 std::string PrettyMethod(const Method* m, bool with_signature = true)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 std::string PrettyMethod(uint32_t method_idx, const DexFile& dex_file, bool with_signature = true);
 
 // Returns a human-readable form of the name of the *class* of the given object.
@@ -187,16 +187,16 @@
 // be "java.lang.String". Given an array of int, the output would be "int[]".
 // Given String.class, the output would be "java.lang.Class<java.lang.String>".
 std::string PrettyTypeOf(const Object* obj)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 // Returns a human-readable form of the name of the given class.
 // Given String.class, the output would be "java.lang.Class<java.lang.String>".
 std::string PrettyClass(const Class* c)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 // Returns a human-readable form of the name of the given class with its class loader.
 std::string PrettyClassAndClassLoader(const Class* c)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 // Returns a human-readable size string such as "1MB".
 std::string PrettySize(size_t size_in_bytes);
@@ -230,10 +230,10 @@
 
 // Returns the JNI native function name for the non-overloaded method 'm'.
 std::string JniShortName(const Method* m)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 // Returns the JNI native function name for the overloaded method 'm'.
 std::string JniLongName(const Method* m)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 bool ReadFileToString(const std::string& file_name, std::string* result);
 
diff --git a/src/verifier/method_verifier.cc b/src/verifier/method_verifier.cc
index 55d537c..813073d 100644
--- a/src/verifier/method_verifier.cc
+++ b/src/verifier/method_verifier.cc
@@ -1029,7 +1029,7 @@
 }
 
 extern "C" void MethodVerifierGdbDump(MethodVerifier* v)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   v->Dump(std::cerr);
 }
 
diff --git a/src/verifier/method_verifier.h b/src/verifier/method_verifier.h
index 244f1f8..51bed6e 100644
--- a/src/verifier/method_verifier.h
+++ b/src/verifier/method_verifier.h
@@ -164,11 +164,11 @@
 
   /* Verify a class. Returns "kNoFailure" on success. */
   static FailureKind VerifyClass(const Class* klass, std::string& error)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static FailureKind VerifyClass(const DexFile* dex_file, DexCache* dex_cache,
                                  ClassLoader* class_loader, uint32_t class_def_idx,
                                  std::string& error)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   uint8_t EncodePcToReferenceMapData() const;
 
@@ -194,7 +194,7 @@
 
   // Dump the state of the verifier, namely each instruction, what flags are set on it, register
   // information
-  void Dump(std::ostream& os) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void Dump(std::ostream& os) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static const std::vector<uint8_t>* GetGcMap(Compiler::MethodReference ref)
       LOCKS_EXCLUDED(gc_maps_lock_);
@@ -203,7 +203,7 @@
   // to the locks held at 'dex_pc' in 'm'.
   static void FindLocksAtDexPc(Method* m, uint32_t dex_pc,
                                std::vector<uint32_t>& monitor_enter_dex_pcs)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void Init();
   static void Shutdown();
@@ -220,7 +220,7 @@
   explicit MethodVerifier(const DexFile* dex_file, DexCache* dex_cache,
       ClassLoader* class_loader, uint32_t class_def_idx, const DexFile::CodeItem* code_item,
       uint32_t method_idx, Method* method, uint32_t access_flags)
-          SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+          SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Adds the given string to the beginning of the last failure message.
   void PrependToLastFailMessage(std::string);
@@ -242,15 +242,15 @@
   static FailureKind VerifyMethod(uint32_t method_idx, const DexFile* dex_file, DexCache* dex_cache,
       ClassLoader* class_loader, uint32_t class_def_idx, const DexFile::CodeItem* code_item,
       Method* method, uint32_t method_access_flags)
-          SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+          SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void VerifyMethodAndDump(Method* method)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Run verification on the method. Returns true if verification completes and false if the input
   // has an irrecoverable corruption.
-  bool Verify() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool Verify() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  void FindLocksAtDexPc() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  void FindLocksAtDexPc() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Compute the width of the instruction at each address in the instruction stream, and store it in
@@ -278,7 +278,7 @@
    * Returns "false" if something in the exception table looks fishy, but we're expecting the
    * exception table to be somewhat sane.
    */
-  bool ScanTryCatchBlocks() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool ScanTryCatchBlocks() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Perform static verification on all instructions in a method.
@@ -384,11 +384,11 @@
                        bool* selfOkay);
 
   /* Perform detailed code-flow analysis on a single method. */
-  bool VerifyCodeFlow() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool VerifyCodeFlow() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Set the register types for the first instruction in the method based on the method signature.
   // This has the side-effect of validating the signature.
-  bool SetTypesFromSignature() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool SetTypesFromSignature() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Perform code flow on a method.
@@ -436,7 +436,7 @@
    * reordering by specifying that you can't execute the new-instance instruction if a register
    * contains an uninitialized instance created by that same instruction.
    */
-  bool CodeFlowVerifyMethod() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  bool CodeFlowVerifyMethod() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Perform verification for a single instruction.
@@ -448,45 +448,45 @@
    * addresses. Does not set or clear any other flags in "insn_flags_".
    */
   bool CodeFlowVerifyInstruction(uint32_t* start_guess)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Perform verification of a new array instruction
   void VerifyNewArray(const DecodedInstruction& dec_insn, bool is_filled,
                       bool is_range)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Perform verification of an aget instruction. The destination register's type will be set to
   // be that of component type of the array unless the array type is unknown, in which case a
   // bottom type inferred from the type of instruction is used. is_primitive is false for an
   // aget-object.
   void VerifyAGet(const DecodedInstruction& insn, const RegType& insn_type,
-                  bool is_primitive) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+                  bool is_primitive) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Perform verification of an aput instruction.
   void VerifyAPut(const DecodedInstruction& insn, const RegType& insn_type,
-                  bool is_primitive) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+                  bool is_primitive) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Lookup instance field and fail for resolution violations
   Field* GetInstanceField(const RegType& obj_type, int field_idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Lookup static field and fail for resolution violations
-  Field* GetStaticField(int field_idx) SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  Field* GetStaticField(int field_idx) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Perform verification of an iget or sget instruction.
   void VerifyISGet(const DecodedInstruction& insn, const RegType& insn_type,
                    bool is_primitive, bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Perform verification of an iput or sput instruction.
   void VerifyISPut(const DecodedInstruction& insn, const RegType& insn_type,
                    bool is_primitive, bool is_static)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Resolves a class based on an index and performs access checks to ensure the referrer can
   // access the resolved class.
   const RegType& ResolveClassAndCheckAccess(uint32_t class_idx)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * For the "move-exception" instruction at "work_insn_idx_", which must be at an exception handler
@@ -494,7 +494,7 @@
    * exception handler can be found or if the Join of exception types fails.
    */
   const RegType& GetCaughtExceptionType()
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Resolves a method based on an index and performs access checks to ensure
@@ -502,7 +502,7 @@
    * Does not throw exceptions.
    */
   Method* ResolveMethodAndCheckAccess(uint32_t method_idx, MethodType method_type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Verify the arguments to a method. We're executing in "method", making
@@ -528,7 +528,7 @@
    */
   Method* VerifyInvocationArgs(const DecodedInstruction& dec_insn,
                                MethodType method_type, bool is_range, bool is_super)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Verify that the target instruction is not "move-exception". It's important that the only way
@@ -543,7 +543,7 @@
   * Returns "false" if an error is encountered.
   */
   bool UpdateRegisters(uint32_t next_insn, const RegisterLine* merge_line)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Is the method being verified a constructor?
   bool IsConstructor() const {
@@ -556,10 +556,10 @@
   }
 
   // Return the register type for the method.
-  const RegType& GetMethodReturnType() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  const RegType& GetMethodReturnType() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Get a type representing the declaring class of the method.
-  const RegType& GetDeclaringClass() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  const RegType& GetDeclaringClass() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
 #if defined(ART_USE_LLVM_COMPILER) || defined(ART_USE_GREENLAND_COMPILER)
   /*
@@ -626,13 +626,13 @@
 
   uint32_t method_idx_;  // The method we're working on.
   // Its object representation if known.
-  Method* foo_method_ GUARDED_BY(GlobalSynchronization::mutator_lock_);
+  Method* foo_method_ GUARDED_BY(Locks::mutator_lock_);
   uint32_t method_access_flags_;  // Method's access flags.
   const DexFile* dex_file_;  // The dex file containing the method.
   // The dex_cache for the declaring class of the method.
-  DexCache* dex_cache_ GUARDED_BY(GlobalSynchronization::mutator_lock_);
+  DexCache* dex_cache_ GUARDED_BY(Locks::mutator_lock_);
   // The class loader for the declaring class of the method.
-  ClassLoader* class_loader_ GUARDED_BY(GlobalSynchronization::mutator_lock_);
+  ClassLoader* class_loader_ GUARDED_BY(Locks::mutator_lock_);
   uint32_t class_def_idx_;  // The class def index of the declaring class of the method.
   const DexFile::CodeItem* code_item_;  // The code item containing the code for the method.
   UniquePtr<InsnFlags[]> insn_flags_;  // Instruction widths and flags, one entry per code unit.
diff --git a/src/verifier/method_verifier_test.cc b/src/verifier/method_verifier_test.cc
index e52feb3..9c9c745 100644
--- a/src/verifier/method_verifier_test.cc
+++ b/src/verifier/method_verifier_test.cc
@@ -28,7 +28,7 @@
 class MethodVerifierTest : public CommonTest {
  protected:
   void VerifyClass(const std::string& descriptor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ASSERT_TRUE(descriptor != NULL);
     Class* klass = class_linker_->FindSystemClass(descriptor.c_str());
 
@@ -38,7 +38,7 @@
   }
 
   void VerifyDexFile(const DexFile* dex)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     ASSERT_TRUE(dex != NULL);
 
     // Verify all the classes defined in this file
diff --git a/src/verifier/reg_type.cc b/src/verifier/reg_type.cc
index 281d96e..f555223 100644
--- a/src/verifier/reg_type.cc
+++ b/src/verifier/reg_type.cc
@@ -385,7 +385,7 @@
 }
 
 std::ostream& operator<<(std::ostream& os, const RegType& rhs)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   os << rhs.Dump();
   return os;
 }
diff --git a/src/verifier/reg_type.h b/src/verifier/reg_type.h
index a0e2ff8..3064f30 100644
--- a/src/verifier/reg_type.h
+++ b/src/verifier/reg_type.h
@@ -118,7 +118,7 @@
 
   // The high half that corresponds to this low half
   const RegType& HighHalf(RegTypeCache* cache) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool IsConstant() const { return type_ == kRegTypeConst; }
   bool IsLongConstant() const { return type_ == kRegTypeConstLo; }
@@ -209,7 +209,7 @@
     return IsReference() && GetClass()->IsObjectClass();
   }
 
-  bool IsArrayTypes() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool IsArrayTypes() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (IsUnresolvedTypes() && !IsUnresolvedMergedReference() && !IsUnresolvedSuperClass()) {
       return GetDescriptor()->CharAt(0) == '[';
     } else if (IsReference()) {
@@ -219,7 +219,7 @@
     }
   }
 
-  bool IsObjectArrayTypes() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  bool IsObjectArrayTypes() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (IsUnresolvedTypes() && !IsUnresolvedMergedReference() && !IsUnresolvedSuperClass()) {
       // Primitive arrays will always resolve
       DCHECK(GetDescriptor()->CharAt(1) == 'L' || GetDescriptor()->CharAt(1) == '[');
@@ -295,27 +295,27 @@
   }
 
   const RegType& GetSuperClass(RegTypeCache* cache) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   std::string Dump(const RegTypeCache* reg_types = NULL) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Can this type access other?
   bool CanAccess(const RegType& other) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   // Can this type access a member with the given properties?
   bool CanAccessMember(Class* klass, uint32_t access_flags) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Can this type be assigned by src?
   bool IsAssignableFrom(const RegType& src) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool Equals(const RegType& other) const { return GetId() == other.GetId(); }
 
   // Compute the merge of this register from one edge (path) with incoming_type from another.
   const RegType& Merge(const RegType& incoming_type, RegTypeCache* reg_types) const
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * A basic Join operation on classes. For a pair of types S and T the Join, written S v T = J, is
@@ -334,7 +334,7 @@
    * [1] Java bytecode verification: algorithms and formalizations, Xavier Leroy
    */
   static Class* ClassJoin(Class* s, Class* t)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
  private:
   friend class RegTypeCache;
diff --git a/src/verifier/reg_type_cache.h b/src/verifier/reg_type_cache.h
index 1287388..5a2c49c 100644
--- a/src/verifier/reg_type_cache.h
+++ b/src/verifier/reg_type_cache.h
@@ -41,65 +41,65 @@
   }
 
   const RegType& From(RegType::Type type, ClassLoader* loader, const char* descriptor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   const RegType& FromClass(Class* klass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   const RegType& FromCat1Const(int32_t value);
   const RegType& FromDescriptor(ClassLoader* loader, const char* descriptor)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   const RegType& FromType(RegType::Type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   const RegType& FromUnresolvedMerge(const RegType& left, const RegType& right);
   const RegType& FromUnresolvedSuperClass(const RegType& child);
 
-  const RegType& Boolean() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Boolean() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeBoolean);
   }
-  const RegType& Byte() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Byte() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeByte);
   }
-  const RegType& Char() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Char() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeChar);
   }
-  const RegType& Short() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Short() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeShort);
   }
-  const RegType& Integer() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Integer() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeInteger);
   }
-  const RegType& Float() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Float() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeFloat);
   }
-  const RegType& Long() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Long() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeLongLo);
   }
-  const RegType& Double() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Double() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeDoubleLo);
   }
 
-  const RegType& JavaLangClass() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& JavaLangClass() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return From(RegType::kRegTypeReference, NULL, "Ljava/lang/Class;");
   }
-  const RegType& JavaLangObject() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& JavaLangObject() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return From(RegType::kRegTypeReference, NULL, "Ljava/lang/Object;");
   }
-  const RegType& JavaLangString() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& JavaLangString() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return From(RegType::kRegTypeReference, NULL, "Ljava/lang/String;");
   }
-  const RegType& JavaLangThrowable() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& JavaLangThrowable() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return From(RegType::kRegTypeReference, NULL, "Ljava/lang/Throwable;");
   }
 
-  const RegType& Undefined() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Undefined() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeUndefined);
   }
-  const RegType& Conflict() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Conflict() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeConflict);
   }
-  const RegType& ConstLo() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& ConstLo() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromType(RegType::kRegTypeConstLo);
   }
-  const RegType& Zero() SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+  const RegType& Zero() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     return FromCat1Const(0);
   }
 
@@ -116,7 +116,7 @@
   const RegType& IntConstant() { return FromCat1Const(std::numeric_limits<jint>::max()); }
 
   const RegType& GetComponentType(const RegType& array, ClassLoader* loader)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
  private:
   // The allocated entries
diff --git a/src/verifier/register_line.cc b/src/verifier/register_line.cc
index ec7891e..4882740 100644
--- a/src/verifier/register_line.cc
+++ b/src/verifier/register_line.cc
@@ -368,7 +368,7 @@
 }
 
 std::ostream& operator<<(std::ostream& os, const RegisterLine& rhs)
-    SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_) {
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   os << rhs.Dump();
   return os;
 }
diff --git a/src/verifier/register_line.h b/src/verifier/register_line.h
index 1d131ad..9f0fcb0 100644
--- a/src/verifier/register_line.h
+++ b/src/verifier/register_line.h
@@ -62,22 +62,22 @@
 
   // Implement category-1 "move" instructions. Copy a 32-bit value from "vsrc" to "vdst".
   void CopyRegister1(uint32_t vdst, uint32_t vsrc, TypeCategory cat)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Implement category-2 "move" instructions. Copy a 64-bit value from "vsrc" to "vdst". This
   // copies both halves of the register.
   void CopyRegister2(uint32_t vdst, uint32_t vsrc)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Implement "move-result". Copy the category-1 value from the result register to another
   // register, and reset the result register.
   void CopyResultRegister1(uint32_t vdst, bool is_reference)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Implement "move-result-wide". Copy the category-2 value from the result register to another
   // register, and reset the result register.
   void CopyResultRegister2(uint32_t vdst)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Set the invisible result register to unknown
   void SetResultTypeToUnknown();
@@ -86,17 +86,17 @@
   // part of a 64-bit value, register N+1 will be set to "newType+1".
   // The register index was validated during the static pass, so we don't need to check it here.
   bool SetRegisterType(uint32_t vdst, const RegType& new_type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /* Set the type of the "result" register. */
   void SetResultRegisterType(const RegType& new_type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Get the type of register vsrc.
   const RegType& GetRegisterType(uint32_t vsrc) const;
 
   bool VerifyRegisterType(uint32_t vsrc, const RegType& check_type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void CopyFromLine(const RegisterLine* src) {
     DCHECK_EQ(num_regs_, src->num_regs_);
@@ -105,7 +105,7 @@
     reg_to_lock_depths_ = src->reg_to_lock_depths_;
   }
 
-  std::string Dump() const SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+  std::string Dump() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void FillWithGarbage() {
     memset(line_.get(), 0xf1, num_regs_ * sizeof(uint16_t));
@@ -122,7 +122,7 @@
    * the new ones at the same time).
    */
   void MarkUninitRefsAsInvalid(const RegType& uninit_type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Update all registers holding "uninit_type" to instead hold the corresponding initialized
@@ -161,7 +161,7 @@
    * versions. We just need to make sure vA is >= 1 and then return vC.
    */
   const RegType& GetInvocationThis(const DecodedInstruction& dec_insn)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Verify types for a simple two-register instruction (e.g. "neg-int").
@@ -169,7 +169,7 @@
    */
   void CheckUnaryOp(const DecodedInstruction& dec_insn,
                     const RegType& dst_type, const RegType& src_type)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Verify types for a simple three-register instruction (e.g. "add-int").
@@ -179,7 +179,7 @@
   void CheckBinaryOp(const DecodedInstruction& dec_insn,
                      const RegType& dst_type, const RegType& src_type1, const RegType& src_type2,
                      bool check_boolean_op)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Verify types for a binary "2addr" operation. "src_type1"/"src_type2"
@@ -189,7 +189,7 @@
                           const RegType& dst_type,
                           const RegType& src_type1, const RegType& src_type2,
                           bool check_boolean_op)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   /*
    * Verify types for A two-register instruction with a literal constant (e.g. "add-int/lit8").
@@ -199,7 +199,7 @@
    */
   void CheckLiteralOp(const DecodedInstruction& dec_insn,
                       const RegType& dst_type, const RegType& src_type, bool check_boolean_op)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Verify/push monitor onto the monitor stack, locking the value in reg_idx at location insn_idx.
   void PushMonitor(uint32_t reg_idx, int32_t insn_idx);
@@ -217,7 +217,7 @@
   bool VerifyMonitorStackEmpty();
 
   bool MergeRegisters(const RegisterLine* incoming_line)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   size_t GetMaxNonZeroReferenceReg(size_t max_ref_reg) {
     size_t i = static_cast<int>(max_ref_reg) < 0 ? 0 : max_ref_reg;
diff --git a/src/well_known_classes.h b/src/well_known_classes.h
index 15961e2..65ee6b4 100644
--- a/src/well_known_classes.h
+++ b/src/well_known_classes.h
@@ -33,7 +33,7 @@
   static void Init(JNIEnv* env);
 
   static Class* ToClass(jclass global_jclass)
-      SHARED_LOCKS_REQUIRED(GlobalSynchronization::mutator_lock_);
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static jclass com_android_dex_Dex;
   static jclass dalvik_system_PathClassLoader;