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

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rev 2896 : 6484965: G1: piggy-back liveness accounting phase on marking
Summary: Remove the separate counting phase of concurrent marking by tracking the amount of marked bytes and the cards spanned by marked objects in marking task/worker thread local data structures, which are updated as individual objects are marked.
Reviewed-by: brutisso

@@ -42,12 +42,11 @@
   ConcurrentGCThread(),
   _cm(cm),
   _started(false),
   _in_progress(false),
   _vtime_accum(0.0),
-  _vtime_mark_accum(0.0),
-  _vtime_count_accum(0.0)
+  _vtime_mark_accum(0.0)
 {
   create_and_start();
 }
 
 class CMCheckpointRootsFinalClosure: public VoidClosure {

@@ -146,40 +145,16 @@
             gclog_or_tty->print_cr("[GC concurrent-mark-restart-for-overflow]");
           }
         }
       } while (cm()->restart_for_overflow());
 
-      double counting_start_time = os::elapsedVTime();
-      if (!cm()->has_aborted()) {
-        double count_start_sec = os::elapsedTime();
-        if (PrintGC) {
-          gclog_or_tty->date_stamp(PrintGCDateStamps);
-          gclog_or_tty->stamp(PrintGCTimeStamps);
-          gclog_or_tty->print_cr("[GC concurrent-count-start]");
-        }
-
-        _sts.join();
-        _cm->calcDesiredRegions();
-        _sts.leave();
-
-        if (!cm()->has_aborted()) {
-          double count_end_sec = os::elapsedTime();
-          if (PrintGC) {
-            gclog_or_tty->date_stamp(PrintGCDateStamps);
-            gclog_or_tty->stamp(PrintGCTimeStamps);
-            gclog_or_tty->print_cr("[GC concurrent-count-end, %1.7lf]",
-                                   count_end_sec - count_start_sec);
-          }
-        }
-      }
-
       double end_time = os::elapsedVTime();
-      _vtime_count_accum += (end_time - counting_start_time);
       // Update the total virtual time before doing this, since it will try
       // to measure it to get the vtime for this marking.  We purposely
       // neglect the presumably-short "completeCleanup" phase here.
       _vtime_accum = (end_time - _vtime_start);
+
       if (!cm()->has_aborted()) {
         if (g1_policy->adaptive_young_list_length()) {
           double now = os::elapsedTime();
           double cleanup_prediction_ms = g1_policy->predict_cleanup_time_ms();
           jlong sleep_time_ms = mmu_tracker->when_ms(now, cleanup_prediction_ms);