Use non volatile lock words in semispace collector.
GSS FormulaEvaluationActions.EvaluateAndApplyChanges:
Before GC time: 9.1s
After GC time: 7.98s
Fixed timing logger errors.
Change-Id: I4193c6ccbbbe7a7220dfaabbf3472a5dcebae616
diff --git a/runtime/mirror/object-inl.h b/runtime/mirror/object-inl.h
index a6db387..2505855 100644
--- a/runtime/mirror/object-inl.h
+++ b/runtime/mirror/object-inl.h
@@ -51,13 +51,14 @@
OFFSET_OF_OBJECT_MEMBER(Object, klass_), new_klass, false);
}
-inline LockWord Object::GetLockWord() {
- return LockWord(GetField32(OFFSET_OF_OBJECT_MEMBER(Object, monitor_), true));
+inline LockWord Object::GetLockWord(bool is_volatile) {
+ return LockWord(GetField32(OFFSET_OF_OBJECT_MEMBER(Object, monitor_), is_volatile));
}
-inline void Object::SetLockWord(LockWord new_val) {
+inline void Object::SetLockWord(LockWord new_val, bool is_volatile) {
// Force use of non-transactional mode and do not check.
- SetField32<false, false>(OFFSET_OF_OBJECT_MEMBER(Object, monitor_), new_val.GetValue(), true);
+ SetField32<false, false>(OFFSET_OF_OBJECT_MEMBER(Object, monitor_), new_val.GetValue(),
+ is_volatile);
}
inline bool Object::CasLockWord(LockWord old_val, LockWord new_val) {
diff --git a/runtime/mirror/object.cc b/runtime/mirror/object.cc
index be7e9f2..766bbc9 100644
--- a/runtime/mirror/object.cc
+++ b/runtime/mirror/object.cc
@@ -150,7 +150,7 @@
int32_t Object::IdentityHashCode() const {
mirror::Object* current_this = const_cast<mirror::Object*>(this);
while (true) {
- LockWord lw = current_this->GetLockWord();
+ LockWord lw = current_this->GetLockWord(false);
switch (lw.GetState()) {
case LockWord::kUnlocked: {
// Try to compare and swap in a new hash, if we succeed we will return the hash on the next
diff --git a/runtime/mirror/object.h b/runtime/mirror/object.h
index f652202..fd31dfb 100644
--- a/runtime/mirror/object.h
+++ b/runtime/mirror/object.h
@@ -100,8 +100,10 @@
return OFFSET_OF_OBJECT_MEMBER(Object, monitor_);
}
- LockWord GetLockWord();
- void SetLockWord(LockWord new_val);
+ // As volatile can be false if the mutators are suspended. This is an optimization since it
+ // avoids the barriers.
+ LockWord GetLockWord(bool as_volatile);
+ void SetLockWord(LockWord new_val, bool as_volatile);
bool CasLockWord(LockWord old_val, LockWord new_val) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
uint32_t GetLockOwnerThreadId();