7173460: G1: java/lang/management/MemoryMXBean/CollectionUsageThreshold.java failes with G1

Summary: The scope of TraceMemoryManagerStats in G1CollectedHeap need to cover the call to G1MonitoringSupport::update_sizes()
Reviewed-by: johnc, jmasa

src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp

@@ -1493,7 +1493,6 @@ bool G1CollectedHeap::do_collection(bool explicit_gc,
     JavaThread::dirty_card_queue_set().abandon_logs();
     assert(!G1DeferredRSUpdate
            || (G1DeferredRSUpdate && (dirty_card_queue_set().completed_buffers_num() == 0)), "Should not be any");
-  }
 
     _young_list->reset_sampled_info();
     // At this point there should be no regions in the
@@ -1508,7 +1507,14 @@ bool G1CollectedHeap::do_collection(bool explicit_gc,
     verify_region_sets_optional();
 
     print_heap_after_gc();
+
+    // We must call G1MonitoringSupport::update_sizes() in the same scoping level
+    // as an active TraceMemoryManagerStats object (i.e. before the destructor for the
+    // TraceMemoryManagerStats is called) so that the G1 memory pools are updated
+    // before any GC notifications are raised.
     g1mm()->update_sizes();
+  }
+
   post_full_gc_dump();
 
   return true;
@@ -3936,7 +3942,6 @@ G1CollectedHeap::do_collection_pause_at_safepoint(double target_pause_time_ms) {
 
       gc_epilogue(false);
     }
-  }
 
     // The closing of the inner scope, immediately above, will complete
     // logging at the "fine" level. The record_collection_pause_end() call
@@ -3954,7 +3959,13 @@ G1CollectedHeap::do_collection_pause_at_safepoint(double target_pause_time_ms) {
     TASKQUEUE_STATS_ONLY(reset_taskqueue_stats());
 
     print_heap_after_gc();
+
+    // We must call G1MonitoringSupport::update_sizes() in the same scoping level
+    // as an active TraceMemoryManagerStats object (i.e. before the destructor for the
+    // TraceMemoryManagerStats is called) so that the G1 memory pools are updated
+    // before any GC notifications are raised.
     g1mm()->update_sizes();
+  }
 
   if (G1SummarizeRSetStats &&
       (G1SummarizeRSetStatsPeriod > 0) &&