src/hotspot/os/windows/os_windows.cpp

*** 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);
  }