src/share/vm/gc_implementation/g1/g1Allocator.cpp

rev 7324 : 8065358: Refactor G1s usage of save_marks and reduce related races
Summary: Stop using save_marks in G1 related code and make setting the replacement field less racy.
Reviewed-by:

@@ -57,11 +57,11 @@
   if (retained_region != NULL &&
       !retained_region->in_collection_set() &&
       !(retained_region->top() == retained_region->end()) &&
       !retained_region->is_empty() &&
       !retained_region->is_humongous()) {
-    retained_region->record_top_and_timestamp();
+    retained_region->record_timestamp();
     // The retained region was added to the old region set when it was
     // retired. We have to remove it now, since we don't allow regions
     // we allocate to in the region sets. We'll re-add it later, when
     // it's retired again.
     _g1h->_old_set.remove(retained_region);

@@ -92,10 +92,13 @@
   // _retained_old_gc_alloc_region. If we don't
   // _retained_old_gc_alloc_region will become NULL. This is what we
   // want either way so no reason to check explicitly for either
   // condition.
   _retained_old_gc_alloc_region = old_gc_alloc_region(context)->release();
+  if (_retained_old_gc_alloc_region != NULL) {
+    _retained_old_gc_alloc_region->record_retained_region();
+  }
 
   if (ResizePLAB) {
     _g1h->_survivor_plab_stats.adjust_desired_plab_sz(no_of_gc_workers);
     _g1h->_old_plab_stats.adjust_desired_plab_sz(no_of_gc_workers);
   }