src/share/vm/gc_implementation/shared/gcTrace.cpp
Index Unified diffs Context diffs Sdiffs Patch New Old Previous File Next File hsx24-atomic Sdiff src/share/vm/gc_implementation/shared

src/share/vm/gc_implementation/shared/gcTrace.cpp

Print this page
rev 4213 : 8008382: Remove redundant use of Atomic::add(jlong, jlong *) in create_new_gc_id()
Summary: There is no need to use atomics in create_new_gc_id() since it is not called by multiple threads in parallel. Also, Atomic::add(jlong, jlong *) is broken for ARM.
Reviewed-by:


  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "gc_implementation/shared/gcHeapSummary.hpp"
  27 #include "gc_implementation/shared/gcTimer.hpp"
  28 #include "gc_implementation/shared/gcTrace.hpp"
  29 #include "memory/referenceProcessorStats.hpp"
  30 #include "runtime/atomic.hpp"
  31 #include "utilities/globalDefinitions.hpp"
  32 
  33 #define assert_unset_gc_id() assert(_shared_gc_info.id() == SharedGCInfo::UNSET_GCID, "GC already started?")
  34 #define assert_set_gc_id() assert(_shared_gc_info.id() != SharedGCInfo::UNSET_GCID, "GC not started?")
  35 
  36 static volatile jlong GCTracer_next_gc_id = 0;
  37 static GCId create_new_gc_id() {
  38   return Atomic::add((jlong)1, &GCTracer_next_gc_id);
  39 }
  40 
  41 void GCTracer::report_gc_start_impl(GCCause::Cause cause, jlong timestamp) {
  42   assert_unset_gc_id();
  43 
  44   GCId gc_id = create_new_gc_id();
  45   _shared_gc_info.set_id(gc_id);
  46   _shared_gc_info.set_cause(cause);
  47   _shared_gc_info.set_start_timestamp(timestamp);
  48 }
  49 
  50 void GCTracer::report_gc_start(GCCause::Cause cause, jlong timestamp) {
  51   assert_unset_gc_id();
  52 
  53   report_gc_start_impl(cause, timestamp);
  54 }
  55 
  56 bool GCTracer::has_reported_gc_start() const {
  57   return _shared_gc_info.id() != SharedGCInfo::UNSET_GCID;
  58 }




  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "gc_implementation/shared/gcHeapSummary.hpp"
  27 #include "gc_implementation/shared/gcTimer.hpp"
  28 #include "gc_implementation/shared/gcTrace.hpp"
  29 #include "memory/referenceProcessorStats.hpp"

  30 #include "utilities/globalDefinitions.hpp"
  31 
  32 #define assert_unset_gc_id() assert(_shared_gc_info.id() == SharedGCInfo::UNSET_GCID, "GC already started?")
  33 #define assert_set_gc_id() assert(_shared_gc_info.id() != SharedGCInfo::UNSET_GCID, "GC not started?")
  34 
  35 static jlong GCTracer_next_gc_id = 0;
  36 static GCId create_new_gc_id() {
  37   return GCTracer_next_gc_id++;
  38 }
  39 
  40 void GCTracer::report_gc_start_impl(GCCause::Cause cause, jlong timestamp) {
  41   assert_unset_gc_id();
  42 
  43   GCId gc_id = create_new_gc_id();
  44   _shared_gc_info.set_id(gc_id);
  45   _shared_gc_info.set_cause(cause);
  46   _shared_gc_info.set_start_timestamp(timestamp);
  47 }
  48 
  49 void GCTracer::report_gc_start(GCCause::Cause cause, jlong timestamp) {
  50   assert_unset_gc_id();
  51 
  52   report_gc_start_impl(cause, timestamp);
  53 }
  54 
  55 bool GCTracer::has_reported_gc_start() const {
  56   return _shared_gc_info.id() != SharedGCInfo::UNSET_GCID;
  57 }


src/share/vm/gc_implementation/shared/gcTrace.cpp
Index Unified diffs Context diffs Sdiffs Patch New Old Previous File Next File