--- old/src/share/vm/gc/g1/g1CardLiveData.cpp	2017-03-21 16:20:06.313641153 -0400
+++ new/src/share/vm/gc/g1/g1CardLiveData.cpp	2017-03-21 16:20:05.113571823 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -265,7 +265,7 @@
   }
 };
 
-class G1CreateCardLiveDataTask: public AbstractGangTask {
+class G1CreateCardLiveDataTask: public G1ParallelizeByRegionsTask {
   // Aggregate the counting data that was constructed concurrently
   // with marking.
   class G1CreateLiveDataClosure : public HeapRegionClosure {
@@ -296,15 +296,13 @@
 
   G1ConcurrentMark* _cm;
   G1CardLiveData* _live_data;
-  HeapRegionClaimer _hr_claimer;
 
 public:
   G1CreateCardLiveDataTask(G1CMBitMap* bitmap,
                            G1CardLiveData* live_data,
                            uint n_workers) :
-      AbstractGangTask("G1 Create Live Data"),
-      _live_data(live_data),
-      _hr_claimer(n_workers) {
+      G1ParallelizeByRegionsTask("G1 Create Live Data", n_workers),
+      _live_data(live_data) {
   }
 
   void work(uint worker_id) {
@@ -313,7 +311,7 @@
     G1CollectedHeap* g1h = G1CollectedHeap::heap();
     G1ConcurrentMark* cm = g1h->concurrent_mark();
     G1CreateLiveDataClosure cl(g1h, cm, cm->nextMarkBitMap(), _live_data);
-    g1h->heap_region_par_iterate(&cl, worker_id, &_hr_claimer);
+    all_heap_regions_work(&cl, worker_id);
   }
 };
 
@@ -328,7 +326,7 @@
   workers->run_task(&cl);
 }
 
-class G1FinalizeCardLiveDataTask: public AbstractGangTask {
+class G1FinalizeCardLiveDataTask: public G1ParallelizeByRegionsTask {
   // Finalizes the liveness counting data.
   // Sets the bits corresponding to the interval [NTAMS, top]
   // (which contains the implicitly live objects) in the
@@ -367,20 +365,16 @@
 
   G1CardLiveData* _live_data;
 
-  HeapRegionClaimer _hr_claimer;
-
 public:
   G1FinalizeCardLiveDataTask(G1CMBitMap* bitmap, G1CardLiveData* live_data, uint n_workers) :
-    AbstractGangTask("G1 Finalize Card Live Data"),
+    G1ParallelizeByRegionsTask("G1 Finalize Card Live Data", n_workers),
     _bitmap(bitmap),
-    _live_data(live_data),
-    _hr_claimer(n_workers) {
+    _live_data(live_data) {
   }
 
   void work(uint worker_id) {
     G1FinalizeCardLiveDataClosure cl(G1CollectedHeap::heap(), _bitmap, _live_data);
-
-    G1CollectedHeap::heap()->heap_region_par_iterate(&cl, worker_id, &_hr_claimer);
+    all_heap_regions_work(&cl, worker_id);
   }
 };
 
@@ -436,7 +430,7 @@
   live_regions_bm().clear();
 }
 
-class G1VerifyCardLiveDataTask: public AbstractGangTask {
+class G1VerifyCardLiveDataTask: public G1ParallelizeByRegionsTask {
   // Heap region closure used for verifying the live count data
   // that was created concurrently and finalized during
   // the remark pause. This closure is applied to the heap
@@ -537,19 +531,16 @@
 
   int  _failures;
 
-  HeapRegionClaimer _hr_claimer;
-
 public:
   G1VerifyCardLiveDataTask(G1CMBitMap* bitmap,
                            G1CardLiveData* act_live_data,
                            uint n_workers)
-  : AbstractGangTask("G1 Verify Card Live Data"),
+  : G1ParallelizeByRegionsTask("G1 Verify Card Live Data", n_workers),
     _g1h(G1CollectedHeap::heap()),
     _mark_bitmap(bitmap),
     _act_live_data(act_live_data),
     _exp_live_data(),
-    _failures(0),
-    _hr_claimer(n_workers) {
+    _failures(0) {
     assert(VerifyDuringGC, "don't call this otherwise");
     _exp_live_data.initialize(_g1h->max_capacity(), _g1h->max_regions());
   }
@@ -559,7 +550,7 @@
                                    _mark_bitmap,
                                    _act_live_data,
                                    &_exp_live_data);
-    _g1h->heap_region_par_iterate(&cl, worker_id, &_hr_claimer);
+    all_heap_regions_work(&cl, worker_id);
 
     Atomic::add(cl.failures(), &_failures);
   }