8183281: Remove unnecessary call to increment_gc_time_stamp
Reviewed-by: sjohanss, tschatzl
--- a/hotspot/src/share/vm/gc/g1/g1CollectedHeap.cpp Mon Jul 03 09:01:34 2017 +0200
+++ b/hotspot/src/share/vm/gc/g1/g1CollectedHeap.cpp Mon Jul 03 14:24:07 2017 +0200
@@ -3266,29 +3266,6 @@
MemoryService::track_memory_usage();
- // In prepare_for_verify() below we'll need to scan the deferred
- // update buffers to bring the RSets up-to-date if
- // G1HRRSFlushLogBuffersOnVerify has been set. While scanning
- // the update buffers we'll probably need to scan cards on the
- // regions we just allocated to (i.e., the GC alloc
- // regions). However, during the last GC we called
- // set_saved_mark() on all the GC alloc regions, so card
- // scanning might skip the [saved_mark_word()...top()] area of
- // those regions (i.e., the area we allocated objects into
- // during the last GC). But it shouldn't. Given that
- // saved_mark_word() is conditional on whether the GC time stamp
- // on the region is current or not, by incrementing the GC time
- // stamp here we invalidate all the GC time stamps on all the
- // regions and saved_mark_word() will simply return top() for
- // all the regions. This is a nicer way of ensuring this rather
- // than iterating over the regions and fixing them. In fact, the
- // GC time stamp increment here also ensures that
- // saved_mark_word() will return top() between pauses, i.e.,
- // during concurrent refinement. So we don't need the
- // is_gc_active() check to decided which top to use when
- // scanning cards (see CR 7039627).
- increment_gc_time_stamp();
-
if (VerifyRememberedSets) {
log_info(gc, verify)("[Verifying RemSets after GC]");
VerifyRegionRemSetClosure v_cl;