6770608: G1: Mutator thread can flush barrier and satb queues during safepoint 6660573: G1: BigApps Failure : guarantee(satb_mq_set.completed_buffers_num() == 0,"invariant") Summary: When exiting a mutator thread is removed from the thread list before it has a chance to flush its SATB and barrier queues. If GC happens at this moment the objects that are refererred from these queues can be moved, which will case a crash. The fix is simply to flush the buffers before removing a thread from the list. Reviewed-by: jcoomes, tonyp

--- a/src/share/vm/runtime/thread.hpp	Fri Nov 07 12:52:16 2008 -0800
+++ b/src/share/vm/runtime/thread.hpp	Fri Nov 14 14:23:05 2008 -0800
@@ -793,6 +793,8 @@
   DirtyCardQueue _dirty_card_queue;      // Thread-local log for dirty cards.
   // Set of all such queues.
   static DirtyCardQueueSet _dirty_card_queue_set;
+
+  void flush_barrier_queues();
 #endif // !SERIALGC
 
   friend class VMThread;