src/hotspot/os/windows/os_windows.cpp

*** 2094,2104 ****
  
  static int check_pending_signals() {
    while (true) {
      for (int i = 0; i < NSIG + 1; i++) {
        jint n = pending_signals[i];
!       if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
          return i;
        }
      }
      JavaThread *thread = JavaThread::current();
  
--- 2094,2104 ----
  
  static int check_pending_signals() {
    while (true) {
      for (int i = 0; i < NSIG + 1; i++) {
        jint n = pending_signals[i];
!       if (n > 0 && n == Atomic::cmpxchg(&pending_signals[i], n, n - 1)) {
          return i;
        }
      }
      JavaThread *thread = JavaThread::current();
  
*** 3749,3759 ****
        warning("crit_sect initialization failed in %s: %d\n", __FILE__, __LINE__);
      } else if (Atomic::load_acquire(&process_exiting) == 0) {
        if (what != EPT_THREAD) {
          // Atomically set process_exiting before the critical section
          // to increase the visibility between racing threads.
!         Atomic::cmpxchg(GetCurrentThreadId(), &process_exiting, (DWORD)0);
        }
        EnterCriticalSection(&crit_sect);
  
        if (what == EPT_THREAD && Atomic::load_acquire(&process_exiting) == 0) {
          // Remove from the array those handles of the threads that have completed exiting.
--- 3749,3759 ----
        warning("crit_sect initialization failed in %s: %d\n", __FILE__, __LINE__);
      } else if (Atomic::load_acquire(&process_exiting) == 0) {
        if (what != EPT_THREAD) {
          // Atomically set process_exiting before the critical section
          // to increase the visibility between racing threads.
!         Atomic::cmpxchg(&process_exiting, (DWORD)0, GetCurrentThreadId());
        }
        EnterCriticalSection(&crit_sect);
  
        if (what == EPT_THREAD && Atomic::load_acquire(&process_exiting) == 0) {
          // Remove from the array those handles of the threads that have completed exiting.
*** 5134,5144 ****
    // Consider: use atomic decrement instead of CAS-loop
  
    int v;
    for (;;) {
      v = _Event;
!     if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
    }
    guarantee((v == 0) || (v == 1), "invariant");
    if (v != 0) return OS_OK;
  
    // Do this the hard way by blocking ...
--- 5134,5144 ----
    // Consider: use atomic decrement instead of CAS-loop
  
    int v;
    for (;;) {
      v = _Event;
!     if (Atomic::cmpxchg(&_Event, v, v-1) == v) break;
    }
    guarantee((v == 0) || (v == 1), "invariant");
    if (v != 0) return OS_OK;
  
    // Do this the hard way by blocking ...
*** 5196,5206 ****
    // may call park().
    // Consider: use atomic decrement instead of CAS-loop
    int v;
    for (;;) {
      v = _Event;
!     if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
    }
    guarantee((v == 0) || (v == 1), "invariant");
    if (v != 0) return;
  
    // Do this the hard way by blocking ...
--- 5196,5206 ----
    // may call park().
    // Consider: use atomic decrement instead of CAS-loop
    int v;
    for (;;) {
      v = _Event;
!     if (Atomic::cmpxchg(&_Event, v, v-1) == v) break;
    }
    guarantee((v == 0) || (v == 1), "invariant");
    if (v != 0) return;
  
    // Do this the hard way by blocking ...
*** 5234,5244 ****
    // that it will take two back-to-back park() calls for the owning
    // thread to block. This has the benefit of forcing a spurious return
    // from the first park() call after an unpark() call which will help
    // shake out uses of park() and unpark() without condition variables.
  
!   if (Atomic::xchg(1, &_Event) >= 0) return;
  
    ::SetEvent(_ParkHandle);
  }
  
  
--- 5234,5244 ----
    // that it will take two back-to-back park() calls for the owning
    // thread to block. This has the benefit of forcing a spurious return
    // from the first park() call after an unpark() call which will help
    // shake out uses of park() and unpark() without condition variables.
  
!   if (Atomic::xchg(&_Event, 1) >= 0) return;
  
    ::SetEvent(_ParkHandle);
  }