--- old/src/hotspot/share/gc/g1/g1DirtyCardQueue.hpp	2019-11-13 17:04:44.366343688 -0800
+++ new/src/hotspot/share/gc/g1/g1DirtyCardQueue.hpp	2019-11-13 17:04:44.034345750 -0800
@@ -78,6 +78,16 @@
 
   void abandon_completed_buffers();
 
+  // Refine the cards in "node" from its index to buffer_size.
+  // Stops processing if SuspendibleThreadSet::should_yield() is true.
+  // Returns true if the entire buffer was processed, false if there
+  // is a pending yield request.  The node's index is updated to exclude
+  // the processed elements, e.g. up to the element before processing
+  // stopped, or one past the last element if the entire buffer was
+  // processed. Increments *total_refined_cards by the number of cards
+  // processed and removed from the buffer.
+  bool refine_buffer(BufferNode* node, uint worker_id, size_t* total_refined_cards);
+
   bool mut_process_buffer(BufferNode* node);
 
   // If the queue contains more cards than configured here, the