*** old/src/os/windows/vm/os_windows.cpp	Sun Mar 20 22:33:18 2011
--- new/src/os/windows/vm/os_windows.cpp	Sun Mar 20 22:33:17 2011

*** 3295,3307 ****
--- 3295,3312 ----
  bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
    assert(!thread->is_Java_thread() || Thread::current() == thread || Threads_lock->owned_by_self(),
           "possibility of dangling Thread pointer");
  
    OSThread* osthread = thread->osthread();
!   bool interrupted = osthread->interrupted();
    interrupted = osthread->interrupted();
    if (clear_interrupted == true) {
+   // There is no synchronization between the setting of the interrupt
+   // and it being cleared here. It is critical - see 6535709 - that
+   // we only clear the interrupt state, and reset the interrupt event,
+   // if we are going to report that we were indeed interrupted - else
+   // an interrupt can be "lost", leading to spurious wakeups or lost wakeups
+   // depending on the timing
+   if (interrupted && clear_interrupted) {
      osthread->set_interrupted(false);
      ResetEvent(osthread->interrupt_event());
    } // Otherwise leave the interrupted state alone
  
    return interrupted;