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

rev 10742 : Make fields used in lock-free algorithms volatile

@@ -94,11 +94,11 @@
 class RefineCardTableEntryClosure: public CardTableEntryClosure {
   bool _concurrent;
 public:
   RefineCardTableEntryClosure() : _concurrent(true) { }
 
-  bool do_card_ptr(jbyte* card_ptr, uint worker_i) {
+  bool do_card_ptr(volatile jbyte* card_ptr, uint worker_i) {
     bool oops_into_cset = G1CollectedHeap::heap()->g1_rem_set()->refine_card(card_ptr, worker_i, false);
     // This path is executed by the concurrent refine or mutator threads,
     // concurrently, and so we do not care if card_ptr contains references
     // that point into the collection set.
     assert(!oops_into_cset, "should be");

@@ -119,11 +119,11 @@
  private:
   size_t _num_dirtied;
   G1CollectedHeap* _g1h;
   G1SATBCardTableLoggingModRefBS* _g1_bs;
 
-  HeapRegion* region_for_card(jbyte* card_ptr) const {
+  HeapRegion* region_for_card(volatile jbyte* card_ptr) const {
     return _g1h->heap_region_containing(_g1_bs->addr_for(card_ptr));
   }
 
   bool will_become_free(HeapRegion* hr) const {
     // A region will be freed by free_collection_set if the region is in the

@@ -133,11 +133,11 @@
 
  public:
   RedirtyLoggedCardTableEntryClosure(G1CollectedHeap* g1h) : CardTableEntryClosure(),
     _num_dirtied(0), _g1h(g1h), _g1_bs(g1h->g1_barrier_set()) { }
 
-  bool do_card_ptr(jbyte* card_ptr, uint worker_i) {
+  bool do_card_ptr(volatile jbyte* card_ptr, uint worker_i) {
     HeapRegion* hr = region_for_card(card_ptr);
 
     // Should only dirty cards in regions that won't be freed.
     if (!will_become_free(hr)) {
       *card_ptr = CardTableModRefBS::dirty_card_val();

@@ -3015,11 +3015,11 @@
                   "Found a not-small remembered set here. This is inconsistent with previous assumptions.");
         G1SATBCardTableLoggingModRefBS* bs = g1h->g1_barrier_set();
         HeapRegionRemSetIterator hrrs(r->rem_set());
         size_t card_index;
         while (hrrs.has_next(card_index)) {
-          jbyte* card_ptr = (jbyte*)bs->byte_for_index(card_index);
+          volatile jbyte* card_ptr = (volatile jbyte*)bs->byte_for_index(card_index);
           // The remembered set might contain references to already freed
           // regions. Filter out such entries to avoid failing card table
           // verification.
           if (g1h->is_in_closed_subset(bs->addr_for(card_ptr))) {
             if (*card_ptr != CardTableModRefBS::dirty_card_val()) {