Thread.interrupt()源码跟踪

1 JDK源码跟踪

1// java.lang.Thread
2public void interrupt() {
3    if (this != Thread.currentThread())
4        checkAccess();
5
6    synchronized (blockerLock) {
7        Interruptible b = blocker;
8        if (b != null) {
9            interrupt0();           // Just to set the interrupt flag
10            b.interrupt(this);
11            return;
12        }
13    }
14    interrupt0();
15}
16
17private native void interrupt0();

2 OpenJDK源码跟踪

• jdk源码（JNI注册）

  // jdk/src/share/native/java/lang/Thread.c:43 static JNINativeMethod methods[] = { {"start0", "()V", (void *)&JVM_StartThread}, {"stop0", "(" OBJ ")V", (void *)&JVM_StopThread}, {"isAlive", "()Z", (void *)&JVM_IsThreadAlive}, {"suspend0", "()V", (void *)&JVM_SuspendThread}, {"resume0", "()V", (void *)&JVM_ResumeThread}, {"setPriority0", "(I)V", (void *)&JVM_SetThreadPriority}, {"yield", "()V", (void *)&JVM_Yield}, {"sleep", "(J)V", (void *)&JVM_Sleep}, {"currentThread", "()" THD, (void *)&JVM_CurrentThread}, {"countStackFrames", "()I", (void *)&JVM_CountStackFrames}, {"interrupt0", "()V", (void *)&JVM_Interrupt}, {"isInterrupted", "(Z)Z", (void *)&JVM_IsInterrupted}, {"holdsLock", "(" OBJ ")Z", (void *)&JVM_HoldsLock}, {"getThreads", "()[" THD, (void *)&JVM_GetAllThreads}, {"dumpThreads", "([" THD ")[[" STE, (void *)&JVM_DumpThreads}, {"setNativeName", "(" STR ")V", (void *)&JVM_SetNativeThreadName}, };

  // jdk/src/share/javavm/export/jvm.h:254 JNIEXPORT void JNICALL JVM_Interrupt(JNIEnv *env, jobject thread);

• java虚拟机（HotSpot实现）：

  // hotspot/src/share/prims/jvm.cpp:3289 JVM_ENTRY(void, JVM_Interrupt(JNIEnv* env, jobject jthread)) JVMWrapper("JVM_Interrupt");

  // Ensure that the C++ Thread and OSThread structures aren't freed before we operate oop java_thread = JNIHandles::resolve_non_null(jthread); MutexLockerEx ml(thread->threadObj() == java_thread ? NULL : Threads_lock); // We need to re-resolve the java_thread, since a GC might have happened during the // acquire of the lock JavaThread* thr = java_lang_Thread::thread(JNIHandles::resolve_non_null(jthread)); if (thr != NULL) { Thread::interrupt(thr); } JVM_END

  // hotspot/src/share/vm/runtime/thraed.cpp:634 ParkEvent * _ParkEvent ; // for synchronized() ParkEvent * _SleepEvent ; // for Thread.sleep ParkEvent * _MutexEvent ; // for native internal Mutex/Monitor,互斥锁 ParkEvent * _MuxEvent ; // for low-level muxAcquire-muxRelease，共享锁

  // hotspot/src/share/vm/runtime/thraed.cpp:804 void Thread::interrupt(Thread* thread) { trace("interrupt", thread); debug_only(check_for_dangling_thread_pointer(thread);) os::interrupt(thread); }

  // hotspot/src/hotspot/os/linux/vm/os_linux.cpp:4192 void os::interrupt(Thread* thread) { assert(Thread::current() == thread || Threads_lock->owned_by_self(), "possibility of dangling Thread pointer");

  OSThread* osthread = thread->osthread();

  if (!osthread->interrupted()) { osthread->set_interrupted(true); // More than one thread can get here with the same value of osthread, // resulting in multiple notifications. We do, however, want the store // to interrupted() to be visible to other threads before we execute unpark(). OrderAccess::fence(); ParkEvent * const slp = thread->_SleepEvent ; // Thread.sleep方法继续运行 if (slp != NULL) slp->unpark() ; }

  // For JSR166. Unpark event if interrupt status already was set if (thread->is_Java_thread()) ((JavaThread*)thread)->parker()->unpark();

  ParkEvent * ev = thread->_ParkEvent ; if (ev != NULL) ev->unpark() ; }

  // hotspot/src/share/vm/runtime/osThread.hpp:很短自己看 volatile jint _interrupted; // Thread.isInterrupted state

  volatile bool interrupted() const{ return _interrupted != 0; }

  void set_interrupted(bool z){ _interrupted = z ? 1 : 0; }