/*
* 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_internal.h"
#include "monitor.h"
#include "mirror/object.h"
#include "scoped_fast_native_object_access.h"
#include "scoped_thread_state_change.h"
#include "ScopedUtfChars.h"
#include "thread.h"
#include "thread_list.h"
#include "verify_object-inl.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)->self->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 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_nativeHoldsLock(JNIEnv* env, jobject java_thread, jobject java_object) {
ScopedObjectAccess soa(env);
mirror::Object* object = soa.Decode<mirror::Object*>(java_object);
if (object == nullptr) {
ThrowNullPointerException("object == null");
return JNI_FALSE;
}
MutexLock mu(soa.Self(), *Locks::thread_list_lock_);
Thread* thread = Thread::FromManagedThread(soa, java_thread);
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, true, false, &timed_out);
if (thread != nullptr) {
{
ScopedObjectAccess soa(env);
thread->SetThreadName(name.c_str());
}
thread_list->Resume(thread, false);
} 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);
mirror::Object* lock = soa.Decode<mirror::Object*>(java_lock);
Monitor::Wait(Thread::Current(), lock, 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[] = {
NATIVE_METHOD(Thread, currentThread, "!()Ljava/lang/Thread;"),
NATIVE_METHOD(Thread, interrupted, "!()Z"),
NATIVE_METHOD(Thread, isInterrupted, "!()Z"),
NATIVE_METHOD(Thread, nativeCreate, "(Ljava/lang/Thread;JZ)V"),
NATIVE_METHOD(Thread, nativeGetStatus, "(Z)I"),
NATIVE_METHOD(Thread, nativeHoldsLock, "(Ljava/lang/Object;)Z"),
NATIVE_METHOD(Thread, nativeInterrupt, "!()V"),
NATIVE_METHOD(Thread, nativeSetName, "(Ljava/lang/String;)V"),
NATIVE_METHOD(Thread, nativeSetPriority, "(I)V"),
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