runtime/native/java_lang_Thread.cc - platform/art - Gitiles

 /*
  * Copyright (C) 2008 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include "java_lang_Thread.h"

 #include "common_throws.h"
 #include "jni/jni_internal.h"
 #include "mirror/object.h"
 #include "monitor.h"
 #include "native_util.h"
 #include "nativehelper/jni_macros.h"
 #include "nativehelper/scoped_utf_chars.h"
 #include "scoped_fast_native_object_access-inl.h"
 #include "scoped_thread_state_change-inl.h"
 #include "thread.h"
 #include "thread_list.h"
 #include "verify_object.h"

 namespace art {

 static jobject Thread_currentThread(JNIEnv* env, jclass) {
   ScopedFastNativeObjectAccess soa(env);
   return soa.AddLocalReference<jobject>(soa.Self()->GetPeer());
 }

 static jboolean Thread_interrupted(JNIEnv* env, jclass) {
   return static_cast<JNIEnvExt*>(env)->GetSelf()->Interrupted() ? JNI_TRUE : JNI_FALSE;
 }

 static jboolean Thread_isInterrupted(JNIEnv* env, jobject java_thread) {
   ScopedFastNativeObjectAccess soa(env);
   MutexLock mu(soa.Self(), *Locks::thread_list_lock_);
   Thread* thread = Thread::FromManagedThread(soa, java_thread);
   return (thread != nullptr) ? thread->IsInterrupted() : JNI_FALSE;
 }

 static void Thread_nativeCreate(JNIEnv* env, jclass, jobject java_thread, jlong stack_size,
                                 jboolean daemon) {
   // There are sections in the zygote that forbid thread creation.
   Runtime* runtime = Runtime::Current();
   if (runtime->IsZygote() && runtime->IsZygoteNoThreadSection()) {
     jclass internal_error = env->FindClass("java/lang/InternalError");
     CHECK(internal_error != nullptr);
     env->ThrowNew(internal_error, "Cannot create threads in zygote");
     return;
   }

   Thread::CreateNativeThread(env, java_thread, stack_size, daemon == JNI_TRUE);
 }

 static jint Thread_nativeGetStatus(JNIEnv* env, jobject java_thread, jboolean has_been_started) {
   // Ordinals from Java's Thread.State.
   const jint kJavaNew = 0;
   const jint kJavaRunnable = 1;
   const jint kJavaBlocked = 2;
   const jint kJavaWaiting = 3;
   const jint kJavaTimedWaiting = 4;
   const jint kJavaTerminated = 5;

   ScopedObjectAccess soa(env);
   ThreadState internal_thread_state = (has_been_started ? kTerminated : kStarting);
   MutexLock mu(soa.Self(), *Locks::thread_list_lock_);
   Thread* thread = Thread::FromManagedThread(soa, java_thread);
   if (thread != nullptr) {
     internal_thread_state = thread->GetState();
   }
   switch (internal_thread_state) {
     case kTerminated:                     return kJavaTerminated;
     case kRunnable:                       return kJavaRunnable;
     case kTimedWaiting:                   return kJavaTimedWaiting;
     case kSleeping:                       return kJavaTimedWaiting;
     case kBlocked:                        return kJavaBlocked;
     case kWaiting:                        return kJavaWaiting;
     case kStarting:                       return kJavaNew;
     case kNative:                         return kJavaRunnable;
     case kWaitingForTaskProcessor:        return kJavaWaiting;
     case kWaitingForLockInflation:        return kJavaWaiting;
     case kWaitingForGcToComplete:         return kJavaWaiting;
     case kWaitingPerformingGc:            return kJavaWaiting;
     case kWaitingForCheckPointsToRun:     return kJavaWaiting;
     case kWaitingForDebuggerSend:         return kJavaWaiting;
     case kWaitingForDebuggerToAttach:     return kJavaWaiting;
     case kWaitingInMainDebuggerLoop:      return kJavaWaiting;
     case kWaitingForDebuggerSuspension:   return kJavaWaiting;
     case kWaitingForDeoptimization:       return kJavaWaiting;
     case kWaitingForGetObjectsAllocated:  return kJavaWaiting;
     case kWaitingForJniOnLoad:            return kJavaWaiting;
     case kWaitingForSignalCatcherOutput:  return kJavaWaiting;
     case kWaitingInMainSignalCatcherLoop: return kJavaWaiting;
     case kWaitingForMethodTracingStart:   return kJavaWaiting;
     case kWaitingForVisitObjects:         return kJavaWaiting;
     case kWaitingWeakGcRootRead:          return kJavaRunnable;
     case kWaitingForGcThreadFlip:         return kJavaWaiting;
     case kSuspended:                      return kJavaRunnable;
     // Don't add a 'default' here so the compiler can spot incompatible enum changes.
   }
   LOG(ERROR) << "Unexpected thread state: " << internal_thread_state;
   return -1;  // Unreachable.
 }

 static jboolean Thread_holdsLock(JNIEnv* env, jclass, jobject java_object) {
   ScopedObjectAccess soa(env);
   ObjPtr<mirror::Object> object = soa.Decode<mirror::Object>(java_object);
   if (object == nullptr) {
     ThrowNullPointerException("object == null");
     return JNI_FALSE;
   }
   Thread* thread = soa.Self();
   return thread->HoldsLock(object);
 }

 static void Thread_nativeInterrupt(JNIEnv* env, jobject java_thread) {
   ScopedFastNativeObjectAccess soa(env);
   MutexLock mu(soa.Self(), *Locks::thread_list_lock_);
   Thread* thread = Thread::FromManagedThread(soa, java_thread);
   if (thread != nullptr) {
     thread->Interrupt(soa.Self());
   }
 }

 static void Thread_nativeSetName(JNIEnv* env, jobject peer, jstring java_name) {
   ScopedUtfChars name(env, java_name);
   {
     ScopedObjectAccess soa(env);
     if (soa.Decode<mirror::Object>(peer) == soa.Self()->GetPeer()) {
       soa.Self()->SetThreadName(name.c_str());
       return;
     }
   }
   // Suspend thread to avoid it from killing itself while we set its name. We don't just hold the
   // thread list lock to avoid this, as setting the thread name causes mutator to lock/unlock
   // in the DDMS send code.
   ThreadList* thread_list = Runtime::Current()->GetThreadList();
   bool timed_out;
   // Take suspend thread lock to avoid races with threads trying to suspend this one.
   Thread* thread = thread_list->SuspendThreadByPeer(peer,
                                                     /* request_suspension */ true,
                                                     SuspendReason::kInternal,
                                                     &timed_out);
   if (thread != nullptr) {
     {
       ScopedObjectAccess soa(env);
       thread->SetThreadName(name.c_str());
     }
     bool resumed = thread_list->Resume(thread, SuspendReason::kInternal);
     DCHECK(resumed);
   } else if (timed_out) {
     LOG(ERROR) << "Trying to set thread name to '" << name.c_str() << "' failed as the thread "
         "failed to suspend within a generous timeout.";
   }
 }

 /*
  * Alter the priority of the specified thread.  "new_priority" will range
  * from Thread.MIN_PRIORITY to Thread.MAX_PRIORITY (1-10), with "normal"
  * threads at Thread.NORM_PRIORITY (5).
  */
 static void Thread_nativeSetPriority(JNIEnv* env, jobject java_thread, jint new_priority) {
   ScopedObjectAccess soa(env);
   MutexLock mu(soa.Self(), *Locks::thread_list_lock_);
   Thread* thread = Thread::FromManagedThread(soa, java_thread);
   if (thread != nullptr) {
     thread->SetNativePriority(new_priority);
   }
 }

 static void Thread_sleep(JNIEnv* env, jclass, jobject java_lock, jlong ms, jint ns) {
   ScopedFastNativeObjectAccess soa(env);
   ObjPtr<mirror::Object> lock = soa.Decode<mirror::Object>(java_lock);
   Monitor::Wait(Thread::Current(), lock.Ptr(), ms, ns, true, kSleeping);
 }

 /*
  * Causes the thread to temporarily pause and allow other threads to execute.
  *
  * The exact behavior is poorly defined.  Some discussion here:
  *   http://www.cs.umd.edu/~pugh/java/memoryModel/archive/0944.html
  */
 static void Thread_yield(JNIEnv*, jobject) {
   sched_yield();
 }

 static JNINativeMethod gMethods[] = {
   FAST_NATIVE_METHOD(Thread, currentThread, "()Ljava/lang/Thread;"),
   FAST_NATIVE_METHOD(Thread, interrupted, "()Z"),
   FAST_NATIVE_METHOD(Thread, isInterrupted, "()Z"),
   NATIVE_METHOD(Thread, nativeCreate, "(Ljava/lang/Thread;JZ)V"),
   NATIVE_METHOD(Thread, nativeGetStatus, "(Z)I"),
   NATIVE_METHOD(Thread, holdsLock, "(Ljava/lang/Object;)Z"),
   FAST_NATIVE_METHOD(Thread, nativeInterrupt, "()V"),
   NATIVE_METHOD(Thread, nativeSetName, "(Ljava/lang/String;)V"),
   NATIVE_METHOD(Thread, nativeSetPriority, "(I)V"),
   FAST_NATIVE_METHOD(Thread, sleep, "(Ljava/lang/Object;JI)V"),
   NATIVE_METHOD(Thread, yield, "()V"),
 };

 void register_java_lang_Thread(JNIEnv* env) {
   REGISTER_NATIVE_METHODS("java/lang/Thread");
 }

 }  // namespace art
	/*
	* Copyright (C) 2008 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include "java_lang_Thread.h"

	#include "common_throws.h"
	#include "jni/jni_internal.h"
	#include "mirror/object.h"
	#include "monitor.h"
	#include "native_util.h"
	#include "nativehelper/jni_macros.h"
	#include "nativehelper/scoped_utf_chars.h"
	#include "scoped_fast_native_object_access-inl.h"
	#include "scoped_thread_state_change-inl.h"
	#include "thread.h"
	#include "thread_list.h"
	#include "verify_object.h"

	namespace art {

	static jobject Thread_currentThread(JNIEnv* env, jclass) {
	ScopedFastNativeObjectAccess soa(env);
	return soa.AddLocalReference<jobject>(soa.Self()->GetPeer());
	}

	static jboolean Thread_interrupted(JNIEnv* env, jclass) {
	return static_cast<JNIEnvExt*>(env)->GetSelf()->Interrupted() ? JNI_TRUE : JNI_FALSE;
	}

	static jboolean Thread_isInterrupted(JNIEnv* env, jobject java_thread) {
	ScopedFastNativeObjectAccess soa(env);
	MutexLock mu(soa.Self(), *Locks::thread_list_lock_);
	Thread* thread = Thread::FromManagedThread(soa, java_thread);
	return (thread != nullptr) ? thread->IsInterrupted() : JNI_FALSE;
	}

	static void Thread_nativeCreate(JNIEnv* env, jclass, jobject java_thread, jlong stack_size,
	jboolean daemon) {
	// There are sections in the zygote that forbid thread creation.
	Runtime* runtime = Runtime::Current();
	if (runtime->IsZygote() && runtime->IsZygoteNoThreadSection()) {
	jclass internal_error = env->FindClass("java/lang/InternalError");
	CHECK(internal_error != nullptr);
	env->ThrowNew(internal_error, "Cannot create threads in zygote");
	return;
	}

	Thread::CreateNativeThread(env, java_thread, stack_size, daemon == JNI_TRUE);
	}

	static jint Thread_nativeGetStatus(JNIEnv* env, jobject java_thread, jboolean has_been_started) {
	// Ordinals from Java's Thread.State.
	const jint kJavaNew = 0;
	const jint kJavaRunnable = 1;
	const jint kJavaBlocked = 2;
	const jint kJavaWaiting = 3;
	const jint kJavaTimedWaiting = 4;
	const jint kJavaTerminated = 5;

	ScopedObjectAccess soa(env);
	ThreadState internal_thread_state = (has_been_started ? kTerminated : kStarting);
	MutexLock mu(soa.Self(), *Locks::thread_list_lock_);
	Thread* thread = Thread::FromManagedThread(soa, java_thread);
	if (thread != nullptr) {
	internal_thread_state = thread->GetState();
	}
	switch (internal_thread_state) {
	case kTerminated: return kJavaTerminated;
	case kRunnable: return kJavaRunnable;
	case kTimedWaiting: return kJavaTimedWaiting;
	case kSleeping: return kJavaTimedWaiting;
	case kBlocked: return kJavaBlocked;
	case kWaiting: return kJavaWaiting;
	case kStarting: return kJavaNew;
	case kNative: return kJavaRunnable;
	case kWaitingForTaskProcessor: return kJavaWaiting;
	case kWaitingForLockInflation: return kJavaWaiting;
	case kWaitingForGcToComplete: return kJavaWaiting;
	case kWaitingPerformingGc: return kJavaWaiting;
	case kWaitingForCheckPointsToRun: return kJavaWaiting;
	case kWaitingForDebuggerSend: return kJavaWaiting;
	case kWaitingForDebuggerToAttach: return kJavaWaiting;
	case kWaitingInMainDebuggerLoop: return kJavaWaiting;
	case kWaitingForDebuggerSuspension: return kJavaWaiting;
	case kWaitingForDeoptimization: return kJavaWaiting;
	case kWaitingForGetObjectsAllocated: return kJavaWaiting;
	case kWaitingForJniOnLoad: return kJavaWaiting;
	case kWaitingForSignalCatcherOutput: return kJavaWaiting;
	case kWaitingInMainSignalCatcherLoop: return kJavaWaiting;
	case kWaitingForMethodTracingStart: return kJavaWaiting;
	case kWaitingForVisitObjects: return kJavaWaiting;
	case kWaitingWeakGcRootRead: return kJavaRunnable;
	case kWaitingForGcThreadFlip: return kJavaWaiting;
	case kSuspended: return kJavaRunnable;
	// Don't add a 'default' here so the compiler can spot incompatible enum changes.
	}
	LOG(ERROR) << "Unexpected thread state: " << internal_thread_state;
	return -1; // Unreachable.
	}

	static jboolean Thread_holdsLock(JNIEnv* env, jclass, jobject java_object) {
	ScopedObjectAccess soa(env);
	ObjPtr<mirror::Object> object = soa.Decode<mirror::Object>(java_object);
	if (object == nullptr) {
	ThrowNullPointerException("object == null");
	return JNI_FALSE;
	}
	Thread* thread = soa.Self();
	return thread->HoldsLock(object);
	}

	static void Thread_nativeInterrupt(JNIEnv* env, jobject java_thread) {
	ScopedFastNativeObjectAccess soa(env);
	MutexLock mu(soa.Self(), *Locks::thread_list_lock_);
	Thread* thread = Thread::FromManagedThread(soa, java_thread);
	if (thread != nullptr) {
	thread->Interrupt(soa.Self());
	}
	}

	static void Thread_nativeSetName(JNIEnv* env, jobject peer, jstring java_name) {
	ScopedUtfChars name(env, java_name);
	{
	ScopedObjectAccess soa(env);
	if (soa.Decode<mirror::Object>(peer) == soa.Self()->GetPeer()) {
	soa.Self()->SetThreadName(name.c_str());
	return;
	}
	}
	// Suspend thread to avoid it from killing itself while we set its name. We don't just hold the
	// thread list lock to avoid this, as setting the thread name causes mutator to lock/unlock
	// in the DDMS send code.
	ThreadList* thread_list = Runtime::Current()->GetThreadList();
	bool timed_out;
	// Take suspend thread lock to avoid races with threads trying to suspend this one.
	Thread* thread = thread_list->SuspendThreadByPeer(peer,
	/* request_suspension */ true,
	SuspendReason::kInternal,
	&timed_out);
	if (thread != nullptr) {
	{
	ScopedObjectAccess soa(env);
	thread->SetThreadName(name.c_str());
	}
	bool resumed = thread_list->Resume(thread, SuspendReason::kInternal);
	DCHECK(resumed);
	} else if (timed_out) {
	LOG(ERROR) << "Trying to set thread name to '" << name.c_str() << "' failed as the thread "
	"failed to suspend within a generous timeout.";
	}
	}

	/*
	* Alter the priority of the specified thread. "new_priority" will range
	* from Thread.MIN_PRIORITY to Thread.MAX_PRIORITY (1-10), with "normal"
	* threads at Thread.NORM_PRIORITY (5).
	*/
	static void Thread_nativeSetPriority(JNIEnv* env, jobject java_thread, jint new_priority) {
	ScopedObjectAccess soa(env);
	MutexLock mu(soa.Self(), *Locks::thread_list_lock_);
	Thread* thread = Thread::FromManagedThread(soa, java_thread);
	if (thread != nullptr) {
	thread->SetNativePriority(new_priority);
	}
	}

	static void Thread_sleep(JNIEnv* env, jclass, jobject java_lock, jlong ms, jint ns) {
	ScopedFastNativeObjectAccess soa(env);
	ObjPtr<mirror::Object> lock = soa.Decode<mirror::Object>(java_lock);
	Monitor::Wait(Thread::Current(), lock.Ptr(), ms, ns, true, kSleeping);
	}

	/*
	* Causes the thread to temporarily pause and allow other threads to execute.
	*
	* The exact behavior is poorly defined. Some discussion here:
	* http://www.cs.umd.edu/~pugh/java/memoryModel/archive/0944.html
	*/
	static void Thread_yield(JNIEnv*, jobject) {
	sched_yield();
	}

	static JNINativeMethod gMethods[] = {
	FAST_NATIVE_METHOD(Thread, currentThread, "()Ljava/lang/Thread;"),
	FAST_NATIVE_METHOD(Thread, interrupted, "()Z"),
	FAST_NATIVE_METHOD(Thread, isInterrupted, "()Z"),
	NATIVE_METHOD(Thread, nativeCreate, "(Ljava/lang/Thread;JZ)V"),
	NATIVE_METHOD(Thread, nativeGetStatus, "(Z)I"),
	NATIVE_METHOD(Thread, holdsLock, "(Ljava/lang/Object;)Z"),
	FAST_NATIVE_METHOD(Thread, nativeInterrupt, "()V"),
	NATIVE_METHOD(Thread, nativeSetName, "(Ljava/lang/String;)V"),
	NATIVE_METHOD(Thread, nativeSetPriority, "(I)V"),
	FAST_NATIVE_METHOD(Thread, sleep, "(Ljava/lang/Object;JI)V"),
	NATIVE_METHOD(Thread, yield, "()V"),
	};

	void register_java_lang_Thread(JNIEnv* env) {
	REGISTER_NATIVE_METHODS("java/lang/Thread");
	}

	} // namespace art