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

*** 3321,3341 ****
        // only iterate over these.  (Since evacuation may add to the mark
        // stack, doing more exposes race conditions.)  If no mark is in
        // progress, this will be zero.
        _cm->set_oops_do_bound();
  
!       if (mark_in_progress())
          concurrent_mark()->newCSet();
  
  #if YOUNG_LIST_VERBOSE
        gclog_or_tty->print_cr("\nBefore choosing collection set.\nYoung_list:");
        _young_list->print();
        g1_policy()->print_collection_set(g1_policy()->inc_cset_head(), gclog_or_tty);
  #endif // YOUNG_LIST_VERBOSE
  
        g1_policy()->choose_collection_set(target_pause_time_ms);
  
        // Nothing to do if we were unable to choose a collection set.
  #if G1_REM_SET_LOGGING
        gclog_or_tty->print_cr("\nAfter pause, heap:");
        print();
  #endif
--- 3321,3352 ----
        // only iterate over these.  (Since evacuation may add to the mark
        // stack, doing more exposes race conditions.)  If no mark is in
        // progress, this will be zero.
        _cm->set_oops_do_bound();
  
!       if (mark_in_progress()) {
          concurrent_mark()->newCSet();
+       }
  
  #if YOUNG_LIST_VERBOSE
        gclog_or_tty->print_cr("\nBefore choosing collection set.\nYoung_list:");
        _young_list->print();
        g1_policy()->print_collection_set(g1_policy()->inc_cset_head(), gclog_or_tty);
  #endif // YOUNG_LIST_VERBOSE
  
        g1_policy()->choose_collection_set(target_pause_time_ms);
  
+       // We have chosen the complete collection set. If marking is
+       // active then, we clear the region fields of any of the
+       // concurrent marking tasks whose region fields point into
+       // the collection set as these values will become stale. This
+       // will cause the owning marking threads to claim a new region
+       // when marking restarts.
+       if (mark_in_progress()) {
+         concurrent_mark()->reset_active_task_region_fields_in_cset();
+       }
+ 
        // Nothing to do if we were unable to choose a collection set.
  #if G1_REM_SET_LOGGING
        gclog_or_tty->print_cr("\nAfter pause, heap:");
        print();
  #endif