src/hotspot/share/jfr/recorder/storage/jfrBuffer.cpp

*** 102,112 ****
  }
  
  const u1* JfrBuffer::concurrent_top() const {
    do {
      const u1* current_top = stable_top();
!     if (Atomic::cmpxchg(MUTEX_CLAIM, &_top, current_top) == current_top) {
        return current_top;
      }
    } while (true);
  }
  
--- 102,112 ----
  }
  
  const u1* JfrBuffer::concurrent_top() const {
    do {
      const u1* current_top = stable_top();
!     if (Atomic::cmpxchg(&_top, current_top, MUTEX_CLAIM) == current_top) {
        return current_top;
      }
    } while (true);
  }
  
*** 126,142 ****
  void JfrBuffer::acquire(const void* id) {
    assert(id != NULL, "invariant");
    const void* current_id;
    do {
      current_id = Atomic::load(&_identity);
!   } while (current_id != NULL || Atomic::cmpxchg(id, &_identity, current_id) != current_id);
  }
  
  bool JfrBuffer::try_acquire(const void* id) {
    assert(id != NULL, "invariant");
    const void* const current_id = Atomic::load(&_identity);
!   return current_id == NULL && Atomic::cmpxchg(id, &_identity, current_id) == current_id;
  }
  
  void JfrBuffer::release() {
    OrderAccess::storestore();
    _identity = NULL;
--- 126,142 ----
  void JfrBuffer::acquire(const void* id) {
    assert(id != NULL, "invariant");
    const void* current_id;
    do {
      current_id = Atomic::load(&_identity);
!   } while (current_id != NULL || Atomic::cmpxchg(&_identity, current_id, id) != current_id);
  }
  
  bool JfrBuffer::try_acquire(const void* id) {
    assert(id != NULL, "invariant");
    const void* const current_id = Atomic::load(&_identity);
!   return current_id == NULL && Atomic::cmpxchg(&_identity, current_id, id) == current_id;
  }
  
  void JfrBuffer::release() {
    OrderAccess::storestore();
    _identity = NULL;