Ejemplo n.º 1
0
void IdealGraphPrinter::clean_up() {
  JavaThread *p;
  for (p = Threads::first(); p; p = p->next()) {
    if (p->is_Compiler_thread()) {
      CompilerThread *c = (CompilerThread *)p;
      IdealGraphPrinter *printer = c->ideal_graph_printer();
      if (printer) {
        delete printer;
      }
      c->set_ideal_graph_printer(NULL);
    }
  }
}
Ejemplo n.º 2
0
int VM_Exit::wait_for_threads_in_native_to_block() {
  // VM exits at safepoint. This function must be called at the final safepoint
  // to wait for threads in _thread_in_native state to be quiescent.
  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");

  Thread * thr_cur = Thread::current();
  Monitor timer(Mutex::leaf, "VM_Exit timer", true,
                Monitor::_safepoint_check_never);

  // Compiler threads need longer wait because they can access VM data directly
  // while in native. If they are active and some structures being used are
  // deleted by the shutdown sequence, they will crash. On the other hand, user
  // threads must go through native=>Java/VM transitions first to access VM
  // data, and they will be stopped during state transition. In theory, we
  // don't have to wait for user threads to be quiescent, but it's always
  // better to terminate VM when current thread is the only active thread, so
  // wait for user threads too. Numbers are in 10 milliseconds.
  int max_wait_user_thread = 30;                  // at least 300 milliseconds
  int max_wait_compiler_thread = 1000;            // at least 10 seconds

  int max_wait = max_wait_compiler_thread;

  int attempts = 0;
  while (true) {
    int num_active = 0;
    int num_active_compiler_thread = 0;

    for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next()) {
      if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
        num_active++;
        if (thr->is_Compiler_thread()) {
          num_active_compiler_thread++;
        }
      }
    }

    if (num_active == 0) {
       return 0;
    } else if (attempts > max_wait) {
       return num_active;
    } else if (num_active_compiler_thread == 0 && attempts > max_wait_user_thread) {
       return num_active;
    }

    attempts++;

    MutexLockerEx ml(&timer, Mutex::_no_safepoint_check_flag);
    timer.wait(Mutex::_no_safepoint_check_flag, 10);
  }
}
IdealGraphPrinter *IdealGraphPrinter::printer() {
  if (PrintIdealGraphLevel == 0) return NULL;

  JavaThread *thread = JavaThread::current();
  if (!thread->is_Compiler_thread()) return NULL;

  CompilerThread *compiler_thread = (CompilerThread *)thread;
  if (compiler_thread->ideal_graph_printer() == NULL) {
    IdealGraphPrinter *printer = new IdealGraphPrinter();
    compiler_thread->set_ideal_graph_printer(printer);
  }

  return compiler_thread->ideal_graph_printer();
}
Ejemplo n.º 4
0
void FlatProfiler::record_thread_ticks() {

  int maxthreads, suspendedthreadcount;
  JavaThread** threadsList;
  bool interval_expired = false;

  if (ProfileIntervals &&
      (FlatProfiler::received_ticks >= interval_ticks_previous + ProfileIntervalsTicks)) {
    interval_expired = true;
    interval_ticks_previous = FlatProfiler::received_ticks;
  }

  // Try not to wait for the Threads_lock
  if (Threads_lock->try_lock()) {
    {  // Threads_lock scope
      maxthreads = Threads::number_of_threads();
      threadsList = NEW_C_HEAP_ARRAY(JavaThread *, maxthreads, mtInternal);
      suspendedthreadcount = 0;
      for (JavaThread* tp = Threads::first(); tp != NULL; tp = tp->next()) {
        if (tp->is_Compiler_thread()) {
          // Only record ticks for active compiler threads
          CompilerThread* cthread = (CompilerThread*)tp;
          if (cthread->task() != NULL) {
            // The compiler is active.  If we need to access any of the fields
            // of the compiler task we should suspend the CompilerThread first.
            FlatProfiler::compiler_ticks += 1;
            continue;
          }
        }

        // First externally suspend all threads by marking each for
        // external suspension - so it will stop at its next transition
        // Then do a safepoint
        ThreadProfiler* pp = tp->get_thread_profiler();
        if (pp != NULL && pp->engaged) {
          MutexLockerEx ml(tp->SR_lock(), Mutex::_no_safepoint_check_flag);
          if (!tp->is_external_suspend() && !tp->is_exiting()) {
            tp->set_external_suspend();
            threadsList[suspendedthreadcount++] = tp;
          }
        }
      }
      Threads_lock->unlock();
    }
Ejemplo n.º 5
0
JavaCallWrapper::JavaCallWrapper(methodHandle callee_method, Handle receiver, JavaValue* result, TRAPS) {
  JavaThread* thread = (JavaThread *)THREAD;
  bool clear_pending_exception = true;

  guarantee(thread->is_Java_thread(), "crucial check - the VM thread cannot and must not escape to Java code");
  assert(!thread->owns_locks(), "must release all locks when leaving VM");
  guarantee(!thread->is_Compiler_thread(), "cannot make java calls from the compiler");
  _result   = result;

  // Allocate handle block for Java code. This must be done before we change thread_state to _thread_in_Java_or_stub,
  // since it can potentially block.
  JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(thread);

  // After this, we are official in JavaCode. This needs to be done before we change any of the thread local
  // info, since we cannot find oops before the new information is set up completely.
  ThreadStateTransition::transition(thread, _thread_in_vm, _thread_in_Java);

  // Make sure that we handle asynchronous stops and suspends _before_ we clear all thread state
  // in JavaCallWrapper::JavaCallWrapper(). This way, we can decide if we need to do any pd actions
  // to prepare for stop/suspend (flush register windows on sparcs, cache sp, or other state).
  if (thread->has_special_runtime_exit_condition()) {
    thread->handle_special_runtime_exit_condition();
    if (HAS_PENDING_EXCEPTION) {
      clear_pending_exception = false;
    }
  }


  // Make sure to set the oop's after the thread transition - since we can block there. No one is GC'ing
  // the JavaCallWrapper before the entry frame is on the stack.
  _callee_method = callee_method();
  _receiver = receiver();

#ifdef CHECK_UNHANDLED_OOPS
  THREAD->allow_unhandled_oop(&_receiver);
#endif // CHECK_UNHANDLED_OOPS

  _thread       = (JavaThread *)thread;
  _handles      = _thread->active_handles();    // save previous handle block & Java frame linkage

  // For the profiler, the last_Java_frame information in thread must always be in
  // legal state. We have no last Java frame if last_Java_sp == NULL so
  // the valid transition is to clear _last_Java_sp and then reset the rest of
  // the (platform specific) state.

  _anchor.copy(_thread->frame_anchor());
  _thread->frame_anchor()->clear();

  debug_only(_thread->inc_java_call_counter());
  _thread->set_active_handles(new_handles);     // install new handle block and reset Java frame linkage

  assert (_thread->thread_state() != _thread_in_native, "cannot set native pc to NULL");

  // clear any pending exception in thread (native calls start with no exception pending)
  if(clear_pending_exception) {
    _thread->clear_pending_exception();
  }

  if (_anchor.last_Java_sp() == NULL) {
    _thread->record_base_of_stack_pointer();
  }
}