--- a/src/hotspot/share/gc/g1/heapRegionManager.cpp	Mon Oct 30 08:34:54 2017 +0100
+++ b/src/hotspot/share/gc/g1/heapRegionManager.cpp	Tue Nov 14 11:33:23 2017 +0100
@@ -327,9 +327,7 @@
   return true;
 }
 
-void HeapRegionManager::par_iterate(HeapRegionClosure* blk, uint worker_id, HeapRegionClaimer* hrclaimer) const {
-  const uint start_index = hrclaimer->start_region_for_worker(worker_id);
-
+void HeapRegionManager::par_iterate(HeapRegionClosure* blk, HeapRegionClaimer* hrclaimer, const uint start_index) const {
   // Every worker will actually look at all regions, skipping over regions that
   // are currently not committed.
   // This also (potentially) iterates over regions newly allocated during GC. This
@@ -493,7 +491,7 @@
   }
 }
 
-uint HeapRegionClaimer::start_region_for_worker(uint worker_id) const {
+uint HeapRegionClaimer::offset_for_worker(uint worker_id) const {
   assert(worker_id < _n_workers, "Invalid worker_id.");
   return _n_regions * worker_id / _n_workers;
 }