src/hotspot/share/prims/jvmtiRawMonitor.cpp

rev 48406 : 8194406: Use Atomic::replace_if_null
Reviewed-by: coleenp, dholmes

*** 125,135 ****
  //
  // -------------------------------------------------------------------------
  
  int JvmtiRawMonitor::SimpleEnter (Thread * Self) {
    for (;;) {
!     if (Atomic::cmpxchg(Self, &_owner, (void*)NULL) == NULL) {
         return OS_OK ;
      }
  
      ObjectWaiter Node (Self) ;
      Self->_ParkEvent->reset() ;     // strictly optional
--- 125,135 ----
  //
  // -------------------------------------------------------------------------
  
  int JvmtiRawMonitor::SimpleEnter (Thread * Self) {
    for (;;) {
!     if (Atomic::replace_if_null(Self, &_owner)) {
         return OS_OK ;
      }
  
      ObjectWaiter Node (Self) ;
      Self->_ParkEvent->reset() ;     // strictly optional
*** 137,147 ****
  
      RawMonitor_lock->lock_without_safepoint_check() ;
      Node._next  = _EntryList ;
      _EntryList  = &Node ;
      OrderAccess::fence() ;
!     if (_owner == NULL && Atomic::cmpxchg(Self, &_owner, (void*)NULL) == NULL) {
          _EntryList = Node._next ;
          RawMonitor_lock->unlock() ;
          return OS_OK ;
      }
      RawMonitor_lock->unlock() ;
--- 137,147 ----
  
      RawMonitor_lock->lock_without_safepoint_check() ;
      Node._next  = _EntryList ;
      _EntryList  = &Node ;
      OrderAccess::fence() ;
!     if (_owner == NULL && Atomic::replace_if_null(Self, &_owner)) {
          _EntryList = Node._next ;
          RawMonitor_lock->unlock() ;
          return OS_OK ;
      }
      RawMonitor_lock->unlock() ;