8202018: Move card table clear before enqueuing pending references
Summary: Move card table clearing in preparation of removal of the Reference enqueue phase.
Reviewed-by: sangheki, sjohanss
--- a/src/hotspot/share/gc/g1/g1CollectedHeap.cpp Thu May 03 14:09:21 2018 +0200
+++ b/src/hotspot/share/gc/g1/g1CollectedHeap.cpp Thu May 03 14:09:39 2018 +0200
@@ -4053,12 +4053,17 @@
}
void G1CollectedHeap::post_evacuate_collection_set(EvacuationInfo& evacuation_info, G1ParScanThreadStateSet* per_thread_states) {
+ // Also cleans the card table from temporary duplicate detection information used
+ // during UpdateRS/ScanRS.
+ g1_rem_set()->cleanup_after_oops_into_collection_set_do();
+
// Process any discovered reference objects - we have
// to do this _before_ we retire the GC alloc regions
// as we may have to copy some 'reachable' referent
// objects (and their reachable sub-graphs) that were
// not copied during the pause.
process_discovered_references(per_thread_states);
+ enqueue_discovered_references(per_thread_states);
G1STWIsAliveClosure is_alive(this);
G1KeepAliveClosure keep_alive(this);
@@ -4081,8 +4086,6 @@
g1_policy()->phase_times()->record_string_dedup_fixup_time(fixup_time_ms);
}
- g1_rem_set()->cleanup_after_oops_into_collection_set_do();
-
if (evacuation_failed()) {
restore_after_evac_failure();
@@ -4094,15 +4097,6 @@
_preserved_marks_set.assert_empty();
- // Enqueue any remaining references remaining on the STW
- // reference processor's discovered lists. We need to do
- // this after the card table is cleaned (and verified) as
- // the act of enqueueing entries on to the pending list
- // will log these updates (and dirty their associated
- // cards). We need these updates logged to update any
- // RSets.
- enqueue_discovered_references(per_thread_states);
-
_allocator->release_gc_alloc_regions(evacuation_info);
merge_per_thread_state_info(per_thread_states);
--- a/src/hotspot/share/gc/g1/g1GCPhaseTimes.cpp Thu May 03 14:09:21 2018 +0200
+++ b/src/hotspot/share/gc/g1/g1GCPhaseTimes.cpp Thu May 03 14:09:39 2018 +0200
@@ -397,6 +397,8 @@
debug_time("Code Roots Fixup", _cur_collection_code_root_fixup_time_ms);
+ debug_time("Clear Card Table", _cur_clear_ct_time_ms);
+
debug_time_for_reference("Reference Processing", _cur_ref_proc_time_ms);
_ref_phase_times.print_all_references(2, false);
@@ -408,8 +410,6 @@
debug_phase(_gc_par_phases[StringDedupTableFixup]);
}
- debug_time("Clear Card Table", _cur_clear_ct_time_ms);
-
if (G1CollectedHeap::heap()->evacuation_failed()) {
debug_time("Evacuation Failure", evac_fail_handling);
trace_time("Recalculate Used", _cur_evac_fail_recalc_used);