--- a/src/hotspot/share/gc/g1/g1CollectedHeap.cpp	Fri Aug 16 11:35:17 2019 -0700
+++ b/src/hotspot/share/gc/g1/g1CollectedHeap.cpp	Fri Aug 16 14:46:52 2019 -0400
@@ -1082,7 +1082,6 @@
   G1BarrierSet::dirty_card_queue_set().abandon_logs();
   assert(G1BarrierSet::dirty_card_queue_set().num_completed_buffers() == 0,
          "DCQS should be empty");
-  redirty_cards_queue_set().verify_empty();
 }
 
 void G1CollectedHeap::verify_after_full_collection() {
@@ -1521,7 +1520,6 @@
   _collection_set(this, _policy),
   _hot_card_cache(NULL),
   _rem_set(NULL),
-  _redirty_cards_queue_set(),
   _cm(NULL),
   _cm_thread(NULL),
   _cr(NULL),
@@ -1691,9 +1689,6 @@
                                                   &bs->dirty_card_queue_buffer_allocator(),
                                                   true); // init_free_ids
 
-  // Use same buffer allocator as dirty card qset, to allow merging.
-  _redirty_cards_queue_set.initialize(&bs->dirty_card_queue_buffer_allocator());
-
   // Create the hot card cache.
   _hot_card_cache = new G1HotCardCache(this);
 
@@ -3028,7 +3023,9 @@
 
         calculate_collection_set(evacuation_info, target_pause_time_ms);
 
+        G1RedirtyCardsQueueSet rdcqs(G1BarrierSet::dirty_card_queue_set().allocator());
         G1ParScanThreadStateSet per_thread_states(this,
+                                                  &rdcqs,
                                                   workers()->active_workers(),
                                                   collection_set()->young_region_length(),
                                                   collection_set()->optional_region_length());
@@ -3040,7 +3037,7 @@
         if (_collection_set.optional_region_length() != 0) {
           evacuate_optional_collection_set(&per_thread_states);
         }
-        post_evacuate_collection_set(evacuation_info, &per_thread_states);
+        post_evacuate_collection_set(evacuation_info, &rdcqs, &per_thread_states);
 
         start_new_collection_set();
 
@@ -3122,15 +3119,15 @@
   return true;
 }
 
-void G1CollectedHeap::remove_self_forwarding_pointers() {
-  G1ParRemoveSelfForwardPtrsTask rsfp_task;
+void G1CollectedHeap::remove_self_forwarding_pointers(G1RedirtyCardsQueueSet* rdcqs) {
+  G1ParRemoveSelfForwardPtrsTask rsfp_task(rdcqs);
   workers()->run_task(&rsfp_task);
 }
 
-void G1CollectedHeap::restore_after_evac_failure() {
+void G1CollectedHeap::restore_after_evac_failure(G1RedirtyCardsQueueSet* rdcqs) {
   double remove_self_forwards_start = os::elapsedTime();
 
-  remove_self_forwarding_pointers();
+  remove_self_forwarding_pointers(rdcqs);
   SharedRestorePreservedMarksTaskExecutor task_executor(workers());
   _preserved_marks_set.restore(&task_executor);
 
@@ -3264,15 +3261,14 @@
   }
 };
 
-void G1CollectedHeap::redirty_logged_cards() {
+void G1CollectedHeap::redirty_logged_cards(G1RedirtyCardsQueueSet* rdcqs) {
   double redirty_logged_cards_start = os::elapsedTime();
 
-  G1RedirtyLoggedCardsTask redirty_task(&redirty_cards_queue_set(), this);
+  G1RedirtyLoggedCardsTask redirty_task(rdcqs, this);
   workers()->run_task(&redirty_task);
 
   G1DirtyCardQueueSet& dcq = G1BarrierSet::dirty_card_queue_set();
-  dcq.merge_bufferlists(&redirty_cards_queue_set());
-  redirty_cards_queue_set().verify_empty();
+  dcq.merge_bufferlists(rdcqs);
 
   phase_times()->record_redirty_logged_cards_time_ms((os::elapsedTime() - redirty_logged_cards_start) * 1000.0);
 }
@@ -3603,8 +3599,6 @@
 
   // Should G1EvacuationFailureALot be in effect for this GC?
   NOT_PRODUCT(set_evacuation_failure_alot_for_current_gc();)
-
-  redirty_cards_queue_set().verify_empty();
 }
 
 class G1EvacuateRegionsBaseTask : public AbstractGangTask {
@@ -3806,7 +3800,9 @@
   _collection_set.abandon_optional_collection_set(per_thread_states);
 }
 
-void G1CollectedHeap::post_evacuate_collection_set(G1EvacuationInfo& evacuation_info, G1ParScanThreadStateSet* per_thread_states) {
+void G1CollectedHeap::post_evacuate_collection_set(G1EvacuationInfo& evacuation_info,
+                                                   G1RedirtyCardsQueueSet* rdcqs,
+                                                   G1ParScanThreadStateSet* per_thread_states) {
   rem_set()->cleanup_after_scan_heap_roots();
 
   // Process any discovered reference objects - we have
@@ -3834,7 +3830,7 @@
   _allocator->release_gc_alloc_regions(evacuation_info);
 
   if (evacuation_failed()) {
-    restore_after_evac_failure();
+    restore_after_evac_failure(rdcqs);
 
     // Reset the G1EvacuationFailureALot counters and flags
     NOT_PRODUCT(reset_evacuation_should_fail();)
@@ -3869,7 +3865,7 @@
 
   purge_code_root_memory();
 
-  redirty_logged_cards();
+  redirty_logged_cards(rdcqs);
 
   free_collection_set(&_collection_set, evacuation_info, per_thread_states->surviving_young_words());