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

rev 3985 : 7132678: G1: verify that the marking bitmaps have no marks for objects over TAMS
Summary: Verify that parts of the marking bitmaps that should not have marks do not have marks, i.e., the parts of the bitmap that cover [TAMS:top) areas for each heap region.
Reviewed-by:

*** 1258,1267 ****
--- 1258,1268 ----
      gclog_or_tty->print(" VerifyDuringGC:(before)");
      Universe::heap()->prepare_for_verify();
      Universe::verify(/* silent */ false,
                       /* option */ VerifyOption_G1UsePrevMarking);
    }
+   g1h->check_bitmaps("Remark Start");
  
    G1CollectorPolicy* g1p = g1h->g1_policy();
    g1p->record_concurrent_mark_remark_start();
  
    double start = os::elapsedTime();
*** 1298,1307 ****
--- 1299,1309 ----
        gclog_or_tty->print(" VerifyDuringGC:(after)");
        Universe::heap()->prepare_for_verify();
        Universe::verify(/* silent */ false,
                         /* option */ VerifyOption_G1UseNextMarking);
      }
+     g1h->check_bitmaps("Remark End");
      assert(!restart_for_overflow(), "sanity");
      // Completely reset the marking state since marking completed
      set_non_marking_state();
    }
  
*** 1952,1961 ****
--- 1954,1964 ----
      gclog_or_tty->print(" VerifyDuringGC:(before)");
      Universe::heap()->prepare_for_verify();
      Universe::verify(/* silent */ false,
                       /* option */ VerifyOption_G1UsePrevMarking);
    }
+   g1h->check_bitmaps("Cleanup Start");
  
    G1CollectorPolicy* g1p = G1CollectedHeap::heap()->g1_policy();
    g1p->record_concurrent_mark_cleanup_start();
  
    double start = os::elapsedTime();
*** 2107,2116 ****
--- 2110,2120 ----
      gclog_or_tty->print(" VerifyDuringGC:(after)");
      Universe::heap()->prepare_for_verify();
      Universe::verify(/* silent */ false,
                       /* option */ VerifyOption_G1UsePrevMarking);
    }
+   g1h->check_bitmaps("Cleanup End");
  
    g1h->verify_region_sets_optional();
  }
  
  void ConcurrentMark::completeCleanup() {
*** 3180,3189 ****
--- 3184,3198 ----
  
  // abandon current marking iteration due to a Full GC
  void ConcurrentMark::abort() {
    // Clear all marks to force marking thread to do nothing
    _nextMarkBitMap->clearAll();
+  
+   // Note we cannot clear the previous marking bitmap here
+   // since VerifyDuringGC verifies the objects marked during
+   // a full GC against the previous bitmap.
+ 
    // Clear the liveness counting data
    clear_all_count_data();
    // Empty mark stack
    reset_marking_state();
    for (uint i = 0; i < _max_worker_id; ++i) {