--- a/hotspot/src/share/vm/gc/g1/g1CollectedHeap.cpp	Mon Oct 26 12:22:24 2015 -0400
+++ b/hotspot/src/share/vm/gc/g1/g1CollectedHeap.cpp	Wed Oct 14 14:51:10 2015 +0200
@@ -3934,9 +3934,13 @@
         _allocator->init_gc_alloc_regions(evacuation_info);
 
         G1ParScanThreadStateSet per_thread_states(this, workers()->active_workers(), g1_policy()->young_cset_region_length());
+        pre_evacuate_collection_set();
+
         // Actually do the work...
         evacuate_collection_set(evacuation_info, &per_thread_states);
 
+        post_evacuate_collection_set(evacuation_info, &per_thread_states);
+
         const size_t* surviving_young_words = per_thread_states.surviving_young_words();
         free_collection_set(g1_policy()->collection_set(), evacuation_info, surviving_young_words);
 
@@ -5166,27 +5170,29 @@
   g1_policy()->phase_times()->record_ref_enq_time(ref_enq_time * 1000.0);
 }
 
-void G1CollectedHeap::evacuate_collection_set(EvacuationInfo& evacuation_info, G1ParScanThreadStateSet* per_thread_states) {
+void G1CollectedHeap::pre_evacuate_collection_set() {
   _expand_heap_after_alloc_failure = true;
   _evacuation_failed = false;
 
-  // Should G1EvacuationFailureALot be in effect for this GC?
-  NOT_PRODUCT(set_evacuation_failure_alot_for_current_gc();)
-
-  g1_rem_set()->prepare_for_oops_into_collection_set_do();
-
   // Disable the hot card cache.
   G1HotCardCache* hot_card_cache = _cg1r->hot_card_cache();
   hot_card_cache->reset_hot_cache_claimed_index();
   hot_card_cache->set_use_cache(false);
 
-  const uint n_workers = workers()->active_workers();
+}
+
+void G1CollectedHeap::evacuate_collection_set(EvacuationInfo& evacuation_info, G1ParScanThreadStateSet* per_thread_states) {
+  g1_rem_set()->prepare_for_oops_into_collection_set_do();
+
+  // Should G1EvacuationFailureALot be in effect for this GC?
+  NOT_PRODUCT(set_evacuation_failure_alot_for_current_gc();)
 
   assert(dirty_card_queue_set().completed_buffers_num() == 0, "Should be empty");
   double start_par_time_sec = os::elapsedTime();
   double end_par_time_sec;
 
   {
+    const uint n_workers = workers()->active_workers();
     G1RootProcessor root_processor(this, n_workers);
     G1ParTask g1_par_task(this, per_thread_states, _task_queues, &root_processor, n_workers);
     // InitialMark needs claim bits to keep track of the marked-through CLDs.
@@ -5236,21 +5242,8 @@
     phase_times->record_string_dedup_fixup_time(fixup_time_ms);
   }
 
-  _allocator->release_gc_alloc_regions(evacuation_info);
   g1_rem_set()->cleanup_after_oops_into_collection_set_do();
 
-  per_thread_states->flush();
-
-  record_obj_copy_mem_stats();
-
-  // Reset and re-enable the hot card cache.
-  // Note the counts for the cards in the regions in the
-  // collection set are reset when the collection set is freed.
-  hot_card_cache->reset_hot_cache();
-  hot_card_cache->set_use_cache(true);
-
-  purge_code_root_memory();
-
   if (evacuation_failed()) {
     remove_self_forwarding_pointers();
 
@@ -5268,6 +5261,23 @@
   // cards). We need these updates logged to update any
   // RSets.
   enqueue_discovered_references(per_thread_states);
+}
+
+void G1CollectedHeap::post_evacuate_collection_set(EvacuationInfo& evacuation_info, G1ParScanThreadStateSet* per_thread_states) {
+  _allocator->release_gc_alloc_regions(evacuation_info);
+
+  per_thread_states->flush();
+
+  record_obj_copy_mem_stats();
+
+  // Reset and re-enable the hot card cache.
+  // Note the counts for the cards in the regions in the
+  // collection set are reset when the collection set is freed.
+  G1HotCardCache* hot_card_cache = _cg1r->hot_card_cache();
+  hot_card_cache->reset_hot_cache();
+  hot_card_cache->set_use_cache(true);
+
+  purge_code_root_memory();
 
   redirty_logged_cards();
 #if defined(COMPILER2) || INCLUDE_JVMCI

--- a/hotspot/src/share/vm/gc/g1/g1CollectedHeap.hpp	Mon Oct 26 12:22:24 2015 -0400
+++ b/hotspot/src/share/vm/gc/g1/g1CollectedHeap.hpp	Wed Oct 14 14:51:10 2015 +0200
@@ -728,7 +728,10 @@
   bool do_collection_pause_at_safepoint(double target_pause_time_ms);
 
   // Actually do the work of evacuating the collection set.
-  void evacuate_collection_set(EvacuationInfo& evacuation_info, G1ParScanThreadStateSet* per_thread_states);
+  virtual void evacuate_collection_set(EvacuationInfo& evacuation_info, G1ParScanThreadStateSet* per_thread_states);
+
+  void pre_evacuate_collection_set();
+  void post_evacuate_collection_set(EvacuationInfo& evacuation_info, G1ParScanThreadStateSet* pss);
 
   // Print the header for the per-thread termination statistics.
   static void print_termination_stats_hdr(outputStream* const st);