src/hotspot/share/runtime/objectMonitor.inline.hpp

rev 54612 : Checkpoint latest preliminary review patches for full OpenJDK review; merge with 8222295.patch.
rev 54613 : imported patch dcubed.monitor_deflate_conc.v2.01
rev 54614 : imported patch dcubed.monitor_deflate_conc.v2.02
rev 54615 : imported patch dcubed.monitor_deflate_conc.v2.03

*** 55,66 ****
    return owner != DEFLATER_MARKER ? owner : NULL;
  }
  
  inline void ObjectMonitor::clear() {
    assert(_header != NULL, "must be non-NULL");
-   assert(_contentions == 0, "must be 0: contentions=%d", _contentions);
    assert(_owner == NULL, "must be NULL: owner=" INTPTR_FORMAT, p2i(_owner));
  
    _header = NULL;
  
    clear_using_JT();
  }
--- 55,66 ----
    return owner != DEFLATER_MARKER ? owner : NULL;
  }
  
  inline void ObjectMonitor::clear() {
    assert(_header != NULL, "must be non-NULL");
    assert(_owner == NULL, "must be NULL: owner=" INTPTR_FORMAT, p2i(_owner));
+   assert(_ref_count == 0, "must be 0: ref_count=%d", _ref_count);
  
    _header = NULL;
  
    clear_using_JT();
  }
*** 69,102 ****
    // Unlike other *_using_JT() functions, we cannot assert
    // AsyncDeflateIdleMonitors or Thread::current()->is_Java_thread()
    // because clear() calls this function for the rest of its checks.
  
    if (AsyncDeflateIdleMonitors) {
!     // Async deflation protocol uses the _header, _contentions and _owner
      // fields. While the ObjectMonitor being deflated is on the global free
!     // list, we leave those three fields alone; _owner == DEFLATER_MARKER
!     // and _contentions < 0 will force any racing threads to retry. The
!     // _header field is used by install_displaced_markword_in_object()
      // in the last part of the deflation protocol so we cannot check
!     // its values here.
      guarantee(_owner == NULL || _owner == DEFLATER_MARKER,
                "must be NULL or DEFLATER_MARKER: owner=" INTPTR_FORMAT,
                p2i(_owner));
!     guarantee(_contentions <= 0, "must be <= 0: contentions=%d", _contentions);
    }
    assert(_waiters == 0, "must be 0: waiters=%d", _waiters);
    assert(_recursions == 0, "must be 0: recursions=" INTPTR_FORMAT, _recursions);
    assert(_object != NULL, "must be non-NULL");
-   // Do not assert _ref_count == 0 here because a racing thread could
-   // increment _ref_count, observe _owner == DEFLATER_MARKER and then
-   // decrement _ref_count.
  
    set_allocation_state(Free);
    _object = NULL;
-   // Do not clear _ref_count here because _ref_count is for indicating
-   // that the ObjectMonitor* is in use which is orthogonal to whether
-   // the ObjectMonitor itself is in use for a locking operation.
  }
  
  inline void* ObjectMonitor::object() const {
    return _object;
  }
--- 69,97 ----
    // Unlike other *_using_JT() functions, we cannot assert
    // AsyncDeflateIdleMonitors or Thread::current()->is_Java_thread()
    // because clear() calls this function for the rest of its checks.
  
    if (AsyncDeflateIdleMonitors) {
!     // Async deflation protocol uses the header, owner and ref_count
      // fields. While the ObjectMonitor being deflated is on the global free
!     // list, we leave those three fields alone; owner == DEFLATER_MARKER
!     // and ref_count < 0 will force any racing threads to retry. The
!     // header field is used by install_displaced_markword_in_object()
      // in the last part of the deflation protocol so we cannot check
!     // its value here.
      guarantee(_owner == NULL || _owner == DEFLATER_MARKER,
                "must be NULL or DEFLATER_MARKER: owner=" INTPTR_FORMAT,
                p2i(_owner));
!     guarantee(_ref_count <= 0, "must be <= 0: ref_count=%d", _ref_count);
    }
+   assert(_contentions == 0, "must be 0: contentions=%d", _contentions);
    assert(_waiters == 0, "must be 0: waiters=%d", _waiters);
    assert(_recursions == 0, "must be 0: recursions=" INTPTR_FORMAT, _recursions);
    assert(_object != NULL, "must be non-NULL");
  
    set_allocation_state(Free);
    _object = NULL;
  }
  
  inline void* ObjectMonitor::object() const {
    return _object;
  }