src/hotspot/share/utilities/waitBarrier_generic.cpp

*** 46,56 ****
      return 0;
    }
    assert(w > 0, "Bad counting");
    // We need an exact count which never goes below zero,
    // otherwise the semaphore may be signalled too many times.
!   if (Atomic::cmpxchg(w - 1, &_waiters, w) == w) {
      _sem_barrier.signal();
      return w - 1;
    }
    return w;
  }
--- 46,56 ----
      return 0;
    }
    assert(w > 0, "Bad counting");
    // We need an exact count which never goes below zero,
    // otherwise the semaphore may be signalled too many times.
!   if (Atomic::cmpxchg(&_waiters, w, w - 1) == w) {
      _sem_barrier.signal();
      return w - 1;
    }
    return w;
  }
*** 80,94 ****
    if (barrier_tag != _barrier_tag) {
      // API specifies wait() must provide a trailing fence.
      OrderAccess::fence();
      return;
    }
!   Atomic::add(1, &_barrier_threads);
    if (barrier_tag != 0 && barrier_tag == _barrier_tag) {
!     Atomic::add(1, &_waiters);
      _sem_barrier.wait();
      // We help out with posting, but we need to do so before we decrement the
      // _barrier_threads otherwise we might wake threads up in next wait.
      GenericWaitBarrier::wake_if_needed();
    }
!   Atomic::add(-1, &_barrier_threads);
  }
--- 80,94 ----
    if (barrier_tag != _barrier_tag) {
      // API specifies wait() must provide a trailing fence.
      OrderAccess::fence();
      return;
    }
!   Atomic::add(&_barrier_threads, 1);
    if (barrier_tag != 0 && barrier_tag == _barrier_tag) {
!     Atomic::add(&_waiters, 1);
      _sem_barrier.wait();
      // We help out with posting, but we need to do so before we decrement the
      // _barrier_threads otherwise we might wake threads up in next wait.
      GenericWaitBarrier::wake_if_needed();
    }
!   Atomic::add(&_barrier_threads, -1);
  }