7096030: G1: PrintGCDetails enhancements

7102445: G1: Unnecessary Resource allocations during RSet scanning
Summary: Add a new per-worker thread line in the PrintGCDetails output. GC Worker Other is the difference between the elapsed time for the parallel phase of the evacuation pause and the sum of the times of the sub-phases (external root scanning, mark stack scanning, RSet updating, RSet scanning, object copying, and termination) for that worker. During RSet scanning, stack allocate DirtyCardToOopClosure objects; allocating these in a resource area was causing abnormally high GC Worker Other times while the worker thread freed ResourceArea chunks.
Reviewed-by: tonyp, jwilhelm, brutisso

src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp

@@ -5502,34 +5502,36 @@ void G1CollectedHeap::cleanUpCardTable() {
   CardTableModRefBS* ct_bs = (CardTableModRefBS*) (barrier_set());
   double start = os::elapsedTime();
 
-  // Iterate over the dirty cards region list.
-  G1ParCleanupCTTask cleanup_task(ct_bs, this);
+  {
+    // Iterate over the dirty cards region list.
+    G1ParCleanupCTTask cleanup_task(ct_bs, this);
 
-  if (ParallelGCThreads > 0) {
-    set_par_threads(workers()->total_workers());
-    workers()->run_task(&cleanup_task);
-    set_par_threads(0);
-  } else {
-    while (_dirty_cards_region_list) {
-      HeapRegion* r = _dirty_cards_region_list;
-      cleanup_task.clear_cards(r);
-      _dirty_cards_region_list = r->get_next_dirty_cards_region();
-      if (_dirty_cards_region_list == r) {
-        // The last region.
-        _dirty_cards_region_list = NULL;
+    if (ParallelGCThreads > 0) {
+      set_par_threads(workers()->total_workers());
+      workers()->run_task(&cleanup_task);
+      set_par_threads(0);
+    } else {
+      while (_dirty_cards_region_list) {
+        HeapRegion* r = _dirty_cards_region_list;
+        cleanup_task.clear_cards(r);
+        _dirty_cards_region_list = r->get_next_dirty_cards_region();
+        if (_dirty_cards_region_list == r) {
+          // The last region.
+          _dirty_cards_region_list = NULL;
+        }
+        r->set_next_dirty_cards_region(NULL);
       }
-      r->set_next_dirty_cards_region(NULL);
     }
+#ifndef PRODUCT
+    if (G1VerifyCTCleanup || VerifyAfterGC) {
+      G1VerifyCardTableCleanup cleanup_verifier(this, ct_bs);
+      heap_region_iterate(&cleanup_verifier);
+    }
+#endif
   }
 
   double elapsed = os::elapsedTime() - start;
   g1_policy()->record_clear_ct_time(elapsed * 1000.0);
-#ifndef PRODUCT
-  if (G1VerifyCTCleanup || VerifyAfterGC) {
-    G1VerifyCardTableCleanup cleanup_verifier(this, ct_bs);
-    heap_region_iterate(&cleanup_verifier);
-  }
-#endif
 }
 
 void G1CollectedHeap::free_collection_set(HeapRegion* cs_head) {

src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp

@@ -320,6 +320,7 @@ G1CollectorPolicy::G1CollectorPolicy() :
   _par_last_termination_attempts = new double[_parallel_gc_threads];
   _par_last_gc_worker_end_times_ms = new double[_parallel_gc_threads];
   _par_last_gc_worker_times_ms = new double[_parallel_gc_threads];
+  _par_last_gc_worker_other_times_ms = new double[_parallel_gc_threads];
 
   // start conservatively
   _expensive_region_limit_ms = 0.5 * (double) MaxGCPauseMillis;
@@ -976,6 +977,7 @@ void G1CollectorPolicy::record_collection_pause_start(double start_time_sec,
     _par_last_termination_attempts[i] = -1234.0;
     _par_last_gc_worker_end_times_ms[i] = -1234.0;
     _par_last_gc_worker_times_ms[i] = -1234.0;
+    _par_last_gc_worker_other_times_ms[i] = -1234.0;
   }
 #endif
 
@@ -984,8 +986,10 @@ void G1CollectorPolicy::record_collection_pause_start(double start_time_sec,
     _cur_aux_times_set[i] = false;
   }
 
-  _satb_drain_time_set = false;
-  _last_satb_drain_processed_buffers = -1;
+  // These are initialized to zero here and they are set during
+  // the evacuation pause if marking is in progress.
+  _cur_satb_drain_time_ms = 0.0;
+  _last_satb_drain_processed_buffers = 0;
 
   _last_young_gc_full = false;
 
@@ -1097,61 +1101,65 @@ void G1CollectorPolicy::print_par_sizes(int level,
     (int)total, (int)avg, (int)min, (int)max, (int)max - (int)min);
 }
 
-void G1CollectorPolicy::print_stats (int level,
-                                     const char* str,
-                                     double value) {
+void G1CollectorPolicy::print_stats(int level,
+                                    const char* str,
+                                    double value) {
   LineBuffer(level).append_and_print_cr("[%s: %5.1lf ms]", str, value);
 }
 
-void G1CollectorPolicy::print_stats (int level,
-                                     const char* str,
-                                     int value) {
+void G1CollectorPolicy::print_stats(int level,
+                                    const char* str,
+                                    int value) {
   LineBuffer(level).append_and_print_cr("[%s: %d]", str, value);
 }
 
-double G1CollectorPolicy::avg_value (double* data) {
+double G1CollectorPolicy::avg_value(double* data) {
   if (G1CollectedHeap::use_parallel_gc_threads()) {
     double ret = 0.0;
-    for (uint i = 0; i < ParallelGCThreads; ++i)
+    for (uint i = 0; i < ParallelGCThreads; ++i) {
       ret += data[i];
+    }
     return ret / (double) ParallelGCThreads;
   } else {
     return data[0];
   }
 }
 
-double G1CollectorPolicy::max_value (double* data) {
+double G1CollectorPolicy::max_value(double* data) {
   if (G1CollectedHeap::use_parallel_gc_threads()) {
     double ret = data[0];
-    for (uint i = 1; i < ParallelGCThreads; ++i)
-      if (data[i] > ret)
+    for (uint i = 1; i < ParallelGCThreads; ++i) {
+      if (data[i] > ret) {
         ret = data[i];
+      }
+    }
     return ret;
   } else {
     return data[0];
   }
 }
 
-double G1CollectorPolicy::sum_of_values (double* data) {
+double G1CollectorPolicy::sum_of_values(double* data) {
   if (G1CollectedHeap::use_parallel_gc_threads()) {
     double sum = 0.0;
-    for (uint i = 0; i < ParallelGCThreads; i++)
+    for (uint i = 0; i < ParallelGCThreads; i++) {
       sum += data[i];
+    }
     return sum;
   } else {
     return data[0];
   }
 }
 
-double G1CollectorPolicy::max_sum (double* data1,
-                                   double* data2) {
+double G1CollectorPolicy::max_sum(double* data1, double* data2) {
   double ret = data1[0] + data2[0];
 
   if (G1CollectedHeap::use_parallel_gc_threads()) {
     for (uint i = 1; i < ParallelGCThreads; ++i) {
       double data = data1[i] + data2[i];
-      if (data > ret)
+      if (data > ret) {
         ret = data;
+      }
     }
   }
   return ret;
@@ -1251,6 +1259,10 @@ void G1CollectorPolicy::record_collection_pause_end() {
 
   _n_pauses++;
 
+  // These values are used to update the summary information that is
+  // displayed when TraceGen0Time is enabled, and are output as part
+  // of the PrintGCDetails output, in the non-parallel case.
+
   double ext_root_scan_time = avg_value(_par_last_ext_root_scan_times_ms);
   double mark_stack_scan_time = avg_value(_par_last_mark_stack_scan_times_ms);
   double update_rs_time = avg_value(_par_last_update_rs_times_ms);
@@ -1260,42 +1272,68 @@ void G1CollectorPolicy::record_collection_pause_end() {
   double obj_copy_time = avg_value(_par_last_obj_copy_times_ms);
   double termination_time = avg_value(_par_last_termination_times_ms);
 
-  double parallel_known_time = update_rs_time +
-                               ext_root_scan_time +
-                               mark_stack_scan_time +
-                               scan_rs_time +
-                               obj_copy_time +
-                               termination_time;
+  double known_time = ext_root_scan_time +
+                      mark_stack_scan_time +
+                      update_rs_time +
+                      scan_rs_time +
+                      obj_copy_time;
+
+  double other_time_ms = elapsed_ms;
+
+  // Subtract the SATB drain time. It's initialized to zero at the
+  // start of the pause and is updated during the pause if marking
+  // is in progress.
+  other_time_ms -= _cur_satb_drain_time_ms;
+
+  if (parallel) {
+    other_time_ms -= _cur_collection_par_time_ms;
+  } else {
+    other_time_ms -= known_time;
+  }
 
-  double parallel_other_time = _cur_collection_par_time_ms - parallel_known_time;
+  // Subtract the time taken to clean the card table from the
+  // current value of "other time"
+  other_time_ms -= _cur_clear_ct_time_ms;
 
-  PauseSummary* summary = _summary;
+  // TraceGen0Time and TraceGen1Time summary info updating.
+  _all_pause_times_ms->add(elapsed_ms);
 
   if (update_stats) {
     _recent_rs_scan_times_ms->add(scan_rs_time);
     _recent_pause_times_ms->add(elapsed_ms);
     _recent_rs_sizes->add(rs_size);
 
-    MainBodySummary* body_summary = summary->main_body_summary();
-    guarantee(body_summary != NULL, "should not be null!");
+    _summary->record_total_time_ms(elapsed_ms);
+    _summary->record_other_time_ms(other_time_ms);
+
+    MainBodySummary* body_summary = _summary->main_body_summary();
+    assert(body_summary != NULL, "should not be null!");
 
-    if (_satb_drain_time_set)
-      body_summary->record_satb_drain_time_ms(_cur_satb_drain_time_ms);
-    else
-      body_summary->record_satb_drain_time_ms(0.0);
+    // This will be non-zero iff marking is currently in progress (i.e.
+    // _g1->mark_in_progress() == true) and the currrent pause was not
+    // an initial mark pause. Since the body_summary items are NumberSeqs,
+    // however, they have to be consistent and updated in lock-step with
+    // each other. Therefore we unconditionally record the SATB drain
+    // time - even if it's zero.
+    body_summary->record_satb_drain_time_ms(_cur_satb_drain_time_ms);
 
     body_summary->record_ext_root_scan_time_ms(ext_root_scan_time);
     body_summary->record_mark_stack_scan_time_ms(mark_stack_scan_time);
     body_summary->record_update_rs_time_ms(update_rs_time);
     body_summary->record_scan_rs_time_ms(scan_rs_time);
     body_summary->record_obj_copy_time_ms(obj_copy_time);
+
     if (parallel) {
       body_summary->record_parallel_time_ms(_cur_collection_par_time_ms);
-      body_summary->record_clear_ct_time_ms(_cur_clear_ct_time_ms);
       body_summary->record_termination_time_ms(termination_time);
+
+      double parallel_known_time = known_time + termination_time;
+      double parallel_other_time = _cur_collection_par_time_ms - parallel_known_time;
       body_summary->record_parallel_other_time_ms(parallel_other_time);
     }
+
     body_summary->record_mark_closure_time_ms(_mark_closure_time_ms);
+    body_summary->record_clear_ct_time_ms(_cur_clear_ct_time_ms);
 
     // We exempt parallel collection from this check because Alloc Buffer
     // fragmentation can produce negative collections.  Same with evac
@@ -1307,6 +1345,7 @@ void G1CollectorPolicy::record_collection_pause_end() {
            || _g1->evacuation_failed()
            || surviving_bytes <= _collection_set_bytes_used_before,
            "Or else negative collection!");
+
     _recent_CS_bytes_used_before->add(_collection_set_bytes_used_before);
     _recent_CS_bytes_surviving->add(surviving_bytes);
 
@@ -1357,6 +1396,13 @@ void G1CollectorPolicy::record_collection_pause_end() {
     }
   }
 
+  for (int i = 0; i < _aux_num; ++i) {
+    if (_cur_aux_times_set[i]) {
+      _all_aux_times_ms[i].add(_cur_aux_times_ms[i]);
+    }
+  }
+
+
   if (G1PolicyVerbose > 1) {
     gclog_or_tty->print_cr("   Recording collection pause(%d)", _n_pauses);
   }
@@ -1383,61 +1429,60 @@ void G1CollectorPolicy::record_collection_pause_end() {
                            recent_avg_pause_time_ratio() * 100.0);
   }
 
-  double other_time_ms = elapsed_ms;
-
-  if (_satb_drain_time_set) {
-    other_time_ms -= _cur_satb_drain_time_ms;
-  }
-
-  if (parallel) {
-    other_time_ms -= _cur_collection_par_time_ms + _cur_clear_ct_time_ms;
-  } else {
-    other_time_ms -=
-      update_rs_time +
-      ext_root_scan_time + mark_stack_scan_time +
-      scan_rs_time + obj_copy_time;
-  }
-
+  // PrintGCDetails output
   if (PrintGCDetails) {
+    bool print_marking_info =
+      _g1->mark_in_progress() && !last_pause_included_initial_mark;
+
     gclog_or_tty->print_cr("%s, %1.8lf secs]",
                            (last_pause_included_initial_mark) ? " (initial-mark)" : "",
                            elapsed_ms / 1000.0);
 
-    if (_satb_drain_time_set) {
+    if (print_marking_info) {
       print_stats(1, "SATB Drain Time", _cur_satb_drain_time_ms);
-    }
-    if (_last_satb_drain_processed_buffers >= 0) {
       print_stats(2, "Processed Buffers", _last_satb_drain_processed_buffers);
     }
+
     if (parallel) {
       print_stats(1, "Parallel Time", _cur_collection_par_time_ms);
-      print_par_stats(2, "GC Worker Start Time", _par_last_gc_worker_start_times_ms);
+      print_par_stats(2, "GC Worker Start", _par_last_gc_worker_start_times_ms);
+      print_par_stats(2, "Ext Root Scanning", _par_last_ext_root_scan_times_ms);
+      if (print_marking_info) {
+        print_par_stats(2, "Mark Stack Scanning", _par_last_mark_stack_scan_times_ms);
+      }
       print_par_stats(2, "Update RS", _par_last_update_rs_times_ms);
       print_par_sizes(3, "Processed Buffers", _par_last_update_rs_processed_buffers);
-      print_par_stats(2, "Ext Root Scanning", _par_last_ext_root_scan_times_ms);
-      print_par_stats(2, "Mark Stack Scanning", _par_last_mark_stack_scan_times_ms);
       print_par_stats(2, "Scan RS", _par_last_scan_rs_times_ms);
       print_par_stats(2, "Object Copy", _par_last_obj_copy_times_ms);
       print_par_stats(2, "Termination", _par_last_termination_times_ms);
       print_par_sizes(3, "Termination Attempts", _par_last_termination_attempts);
-      print_par_stats(2, "GC Worker End Time", _par_last_gc_worker_end_times_ms);
+      print_par_stats(2, "GC Worker End", _par_last_gc_worker_end_times_ms);
 
       for (int i = 0; i < _parallel_gc_threads; i++) {
         _par_last_gc_worker_times_ms[i] = _par_last_gc_worker_end_times_ms[i] - _par_last_gc_worker_start_times_ms[i];
-      }
-      print_par_stats(2, "GC Worker Times", _par_last_gc_worker_times_ms);
 
-      print_stats(2, "Parallel Other", parallel_other_time);
-      print_stats(1, "Clear CT", _cur_clear_ct_time_ms);
+        double worker_known_time = _par_last_ext_root_scan_times_ms[i] +
+                                   _par_last_mark_stack_scan_times_ms[i] +
+                                   _par_last_update_rs_times_ms[i] +
+                                   _par_last_scan_rs_times_ms[i] +
+                                   _par_last_obj_copy_times_ms[i] +
+                                   _par_last_termination_times_ms[i];
+
+        _par_last_gc_worker_other_times_ms[i] = _cur_collection_par_time_ms - worker_known_time;
+      }
+      print_par_stats(2, "GC Worker", _par_last_gc_worker_times_ms);
+      print_par_stats(2, "GC Worker Other", _par_last_gc_worker_other_times_ms);
     } else {
-      print_stats(1, "Update RS", update_rs_time);
-      print_stats(2, "Processed Buffers",
-                  (int)update_rs_processed_buffers);
       print_stats(1, "Ext Root Scanning", ext_root_scan_time);
-      print_stats(1, "Mark Stack Scanning", mark_stack_scan_time);
+      if (print_marking_info) {
+        print_stats(1, "Mark Stack Scanning", mark_stack_scan_time);
+      }
+      print_stats(1, "Update RS", update_rs_time);
+      print_stats(2, "Processed Buffers", (int)update_rs_processed_buffers);
       print_stats(1, "Scan RS", scan_rs_time);
       print_stats(1, "Object Copying", obj_copy_time);
     }
+    print_stats(1, "Clear CT", _cur_clear_ct_time_ms);
 #ifndef PRODUCT
     print_stats(1, "Cur Clear CC", _cur_clear_cc_time_ms);
     print_stats(1, "Cum Clear CC", _cum_clear_cc_time_ms);
@@ -1461,16 +1506,6 @@ void G1CollectorPolicy::record_collection_pause_end() {
     }
   }
 
-  _all_pause_times_ms->add(elapsed_ms);
-  if (update_stats) {
-    summary->record_total_time_ms(elapsed_ms);
-    summary->record_other_time_ms(other_time_ms);
-  }
-  for (int i = 0; i < _aux_num; ++i)
-    if (_cur_aux_times_set[i]) {
-      _all_aux_times_ms[i].add(_cur_aux_times_ms[i]);
-    }
-
   // Update the efficiency-since-mark vars.
   double proc_ms = elapsed_ms * (double) _parallel_gc_threads;
   if (elapsed_ms < MIN_TIMER_GRANULARITY) {
@@ -2138,17 +2173,17 @@ void G1CollectorPolicy::count_CS_bytes_used() {
   _g1->collection_set_iterate(&cs_closure);
 }
 
-void G1CollectorPolicy::print_summary (int level,
-                                       const char* str,
-                                       NumberSeq* seq) const {
+void G1CollectorPolicy::print_summary(int level,
+                                      const char* str,
+                                      NumberSeq* seq) const {
   double sum = seq->sum();
   LineBuffer(level + 1).append_and_print_cr("%-24s = %8.2lf s (avg = %8.2lf ms)",
                 str, sum / 1000.0, seq->avg());
 }
 
-void G1CollectorPolicy::print_summary_sd (int level,
-                                          const char* str,
-                                          NumberSeq* seq) const {
+void G1CollectorPolicy::print_summary_sd(int level,
+                                         const char* str,
+                                         NumberSeq* seq) const {
   print_summary(level, str, seq);
   LineBuffer(level + 6).append_and_print_cr("(num = %5d, std dev = %8.2lf ms, max = %8.2lf ms)",
                 seq->num(), seq->sd(), seq->maximum());
@@ -2211,20 +2246,18 @@ void G1CollectorPolicy::print_summary(PauseSummary* summary) const {
       print_summary(1, "SATB Drain", body_summary->get_satb_drain_seq());
       if (parallel) {
         print_summary(1, "Parallel Time", body_summary->get_parallel_seq());
+        print_summary(2, "Ext Root Scanning", body_summary->get_ext_root_scan_seq());
+        print_summary(2, "Mark Stack Scanning", body_summary->get_mark_stack_scan_seq());
         print_summary(2, "Update RS", body_summary->get_update_rs_seq());
-        print_summary(2, "Ext Root Scanning",
-                      body_summary->get_ext_root_scan_seq());
-        print_summary(2, "Mark Stack Scanning",
-                      body_summary->get_mark_stack_scan_seq());
         print_summary(2, "Scan RS", body_summary->get_scan_rs_seq());
         print_summary(2, "Object Copy", body_summary->get_obj_copy_seq());
         print_summary(2, "Termination", body_summary->get_termination_seq());
-        print_summary(2, "Other", body_summary->get_parallel_other_seq());
+        print_summary(2, "Parallel Other", body_summary->get_parallel_other_seq());
         {
           NumberSeq* other_parts[] = {
-            body_summary->get_update_rs_seq(),
             body_summary->get_ext_root_scan_seq(),
             body_summary->get_mark_stack_scan_seq(),
+            body_summary->get_update_rs_seq(),
             body_summary->get_scan_rs_seq(),
             body_summary->get_obj_copy_seq(),
             body_summary->get_termination_seq()
@@ -2234,18 +2267,16 @@ void G1CollectorPolicy::print_summary(PauseSummary* summary) const {
           check_other_times(2, body_summary->get_parallel_other_seq(),
                             &calc_other_times_ms);
         }
-        print_summary(1, "Mark Closure", body_summary->get_mark_closure_seq());
-        print_summary(1, "Clear CT", body_summary->get_clear_ct_seq());
       } else {
+        print_summary(1, "Ext Root Scanning", body_summary->get_ext_root_scan_seq());
+        print_summary(1, "Mark Stack Scanning", body_summary->get_mark_stack_scan_seq());
         print_summary(1, "Update RS", body_summary->get_update_rs_seq());
-        print_summary(1, "Ext Root Scanning",
-                      body_summary->get_ext_root_scan_seq());
-        print_summary(1, "Mark Stack Scanning",
-                      body_summary->get_mark_stack_scan_seq());
         print_summary(1, "Scan RS", body_summary->get_scan_rs_seq());
         print_summary(1, "Object Copy", body_summary->get_obj_copy_seq());
       }
     }
+    print_summary(1, "Mark Closure", body_summary->get_mark_closure_seq());
+    print_summary(1, "Clear CT", body_summary->get_clear_ct_seq());
     print_summary(1, "Other", summary->get_other_seq());
     {
       if (body_summary != NULL) {

src/share/vm/gc_implementation/g1/g1CollectorPolicy.hpp

@@ -74,7 +74,7 @@ class MainBodySummary: public CHeapObj {
     define_num_seq(termination) // parallel only
     define_num_seq(parallel_other) // parallel only
   define_num_seq(mark_closure)
-  define_num_seq(clear_ct)  // parallel only
+  define_num_seq(clear_ct)
 };
 
 class Summary: public PauseSummary,
@@ -115,7 +115,6 @@ private:
   double _cur_collection_par_time_ms;
   double _cur_satb_drain_time_ms;
   double _cur_clear_ct_time_ms;
-  bool   _satb_drain_time_set;
   double _cur_ref_proc_time_ms;
   double _cur_ref_enq_time_ms;
 
@@ -176,6 +175,11 @@ private:
   double* _par_last_gc_worker_end_times_ms;
   double* _par_last_gc_worker_times_ms;
 
+  // Each workers 'other' time i.e. the elapsed time of the parallel
+  // phase of the pause minus the sum of the individual sub-phase
+  // times for a given worker thread.
+  double* _par_last_gc_worker_other_times_ms;
+
   // indicates whether we are in full young or partially young GC mode
   bool _full_young_gcs;
 
@@ -892,11 +896,12 @@ public:
   }
 
   void record_satb_drain_time(double ms) {
+    assert(_g1->mark_in_progress(), "shouldn't be here otherwise");
     _cur_satb_drain_time_ms = ms;
-    _satb_drain_time_set    = true;
   }
 
-  void record_satb_drain_processed_buffers (int processed_buffers) {
+  void record_satb_drain_processed_buffers(int processed_buffers) {
+    assert(_g1->mark_in_progress(), "shouldn't be here otherwise");
     _last_satb_drain_processed_buffers = processed_buffers;
   }
 

src/share/vm/gc_implementation/g1/g1RemSet.cpp

@@ -122,10 +122,10 @@ public:
   void set_try_claimed() { _try_claimed = true; }
 
   void scanCard(size_t index, HeapRegion *r) {
-    DirtyCardToOopClosure* cl =
-      r->new_dcto_closure(_oc,
-                         CardTableModRefBS::Precise,
-                         HeapRegionDCTOC::IntoCSFilterKind);
+    // Stack allocate the DirtyCardToOopClosure instance
+    HeapRegionDCTOC cl(_g1h, r, _oc,
+                       CardTableModRefBS::Precise,
+                       HeapRegionDCTOC::IntoCSFilterKind);
 
     // Set the "from" region in the closure.
     _oc->set_region(r);
@@ -140,7 +140,7 @@ public:
       // scans (the rsets of the regions in the cset can intersect).
       _ct_bs->set_card_claimed(index);
       _cards_done++;
-      cl->do_MemRegion(mr);
+      cl.do_MemRegion(mr);
     }
   }
 

src/share/vm/gc_implementation/g1/heapRegion.cpp

@@ -340,14 +340,6 @@ void HeapRegion::reset_after_compaction() {
   init_top_at_mark_start();
 }
 
-DirtyCardToOopClosure*
-HeapRegion::new_dcto_closure(OopClosure* cl,
-                             CardTableModRefBS::PrecisionStyle precision,
-                             HeapRegionDCTOC::FilterKind fk) {
-  return new HeapRegionDCTOC(G1CollectedHeap::heap(),
-                             this, cl, precision, fk);
-}
-
 void HeapRegion::hr_clear(bool par, bool clear_space) {
   assert(_humongous_type == NotHumongous,
          "we should have already filtered out humongous regions");

src/share/vm/gc_implementation/g1/heapRegion.hpp

@@ -577,11 +577,6 @@ class HeapRegion: public G1OffsetTableContigSpace {
   // allocated in the current region before the last call to "save_mark".
   void oop_before_save_marks_iterate(OopClosure* cl);
 
-  DirtyCardToOopClosure*
-  new_dcto_closure(OopClosure* cl,
-                   CardTableModRefBS::PrecisionStyle precision,
-                   HeapRegionDCTOC::FilterKind fk);
-
   // Note the start or end of marking. This tells the heap region
   // that the collector is about to start or has finished (concurrently)
   // marking the heap.