8183539: Remove G1RemSet::_into_cset_dirty_card_queue_set
Reviewed-by: tschatzl, mgerdin
--- a/hotspot/src/share/vm/gc/g1/g1GCPhaseTimes.cpp Fri Jul 14 14:04:57 2017 +0200
+++ b/hotspot/src/share/vm/gc/g1/g1GCPhaseTimes.cpp Mon Jul 17 11:37:00 2017 +0200
@@ -116,7 +116,6 @@
_cur_collection_code_root_fixup_time_ms = 0.0;
_cur_strong_code_root_purge_time_ms = 0.0;
_cur_evac_fail_recalc_used = 0.0;
- _cur_evac_fail_restore_remsets = 0.0;
_cur_evac_fail_remove_self_forwards = 0.0;
_cur_string_dedup_fixup_time_ms = 0.0;
_cur_prepare_tlab_time_ms = 0.0;
@@ -346,8 +345,7 @@
double G1GCPhaseTimes::print_post_evacuate_collection_set() const {
const double evac_fail_handling = _cur_evac_fail_recalc_used +
- _cur_evac_fail_remove_self_forwards +
- _cur_evac_fail_restore_remsets;
+ _cur_evac_fail_remove_self_forwards;
const double sum_ms = evac_fail_handling +
_cur_collection_code_root_fixup_time_ms +
_recorded_preserve_cm_referents_time_ms +
@@ -383,7 +381,6 @@
debug_time("Evacuation Failure", evac_fail_handling);
trace_time("Recalculate Used", _cur_evac_fail_recalc_used);
trace_time("Remove Self Forwards",_cur_evac_fail_remove_self_forwards);
- trace_time("Restore RemSet", _cur_evac_fail_restore_remsets);
}
debug_time("Reference Enqueuing", _cur_ref_enq_time_ms);
--- a/hotspot/src/share/vm/gc/g1/g1GCPhaseTimes.hpp Fri Jul 14 14:04:57 2017 +0200
+++ b/hotspot/src/share/vm/gc/g1/g1GCPhaseTimes.hpp Mon Jul 17 11:37:00 2017 +0200
@@ -105,7 +105,6 @@
double _cur_strong_code_root_purge_time_ms;
double _cur_evac_fail_recalc_used;
- double _cur_evac_fail_restore_remsets;
double _cur_evac_fail_remove_self_forwards;
double _cur_string_dedup_fixup_time_ms;
@@ -228,10 +227,6 @@
_cur_evac_fail_recalc_used = ms;
}
- void record_evac_fail_restore_remsets(double ms) {
- _cur_evac_fail_restore_remsets = ms;
- }
-
void record_evac_fail_remove_self_forwards(double ms) {
_cur_evac_fail_remove_self_forwards = ms;
}
--- a/hotspot/src/share/vm/gc/g1/g1OopClosures.hpp Fri Jul 14 14:04:57 2017 +0200
+++ b/hotspot/src/share/vm/gc/g1/g1OopClosures.hpp Mon Jul 17 11:37:00 2017 +0200
@@ -62,16 +62,12 @@
// Used during the Update RS phase to refine remaining cards in the DCQ during garbage collection.
class G1ScanObjsDuringUpdateRSClosure: public G1ScanClosureBase {
uint _worker_i;
- bool _has_refs_into_cset;
public:
G1ScanObjsDuringUpdateRSClosure(G1CollectedHeap* g1h,
G1ParScanThreadState* pss,
uint worker_i) :
- G1ScanClosureBase(g1h, pss), _has_refs_into_cset(false), _worker_i(worker_i) { }
-
- void reset_has_refs_into_cset() { _has_refs_into_cset = false; }
- bool has_refs_into_cset() const { return _has_refs_into_cset; }
+ G1ScanClosureBase(g1h, pss), _worker_i(worker_i) { }
template <class T> void do_oop_nv(T* p);
virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
--- a/hotspot/src/share/vm/gc/g1/g1OopClosures.inline.hpp Fri Jul 14 14:04:57 2017 +0200
+++ b/hotspot/src/share/vm/gc/g1/g1OopClosures.inline.hpp Mon Jul 17 11:37:00 2017 +0200
@@ -166,8 +166,6 @@
// Since the source is always from outside the collection set, here we implicitly know
// that this is a cross-region reference too.
prefetch_and_push(p, obj);
-
- _has_refs_into_cset = true;
} else {
HeapRegion* to = _g1->heap_region_containing(obj);
if (_from == to) {
--- a/hotspot/src/share/vm/gc/g1/g1RemSet.cpp Fri Jul 14 14:04:57 2017 +0200
+++ b/hotspot/src/share/vm/gc/g1/g1RemSet.cpp Mon Jul 17 11:37:00 2017 +0200
@@ -288,17 +288,7 @@
_ct_bs(ct_bs),
_g1p(_g1->g1_policy()),
_hot_card_cache(hot_card_cache),
- _prev_period_summary(),
- _into_cset_dirty_card_queue_set(false)
-{
- // Initialize the card queue set used to hold cards containing
- // references into the collection set.
- _into_cset_dirty_card_queue_set.initialize(DirtyCardQ_CBL_mon,
- DirtyCardQ_FL_lock,
- -1, // never trigger processing
- -1, // no limit on length
- Shared_DirtyCardQ_lock,
- &JavaThread::dirty_card_queue_set());
+ _prev_period_summary() {
}
G1RemSet::~G1RemSet() {
@@ -446,18 +436,13 @@
p->record_time_secs(G1GCPhaseTimes::CodeRoots, worker_i, cl.strong_code_root_scan_time_sec());
}
-// Closure used for updating RSets and recording references that
-// point into the collection set. Only called during an
-// evacuation pause.
+// Closure used for updating rem sets. Only called during an evacuation pause.
class G1RefineCardClosure: public CardTableEntryClosure {
G1RemSet* _g1rs;
- DirtyCardQueue* _into_cset_dcq;
G1ScanObjsDuringUpdateRSClosure* _update_rs_cl;
public:
- G1RefineCardClosure(G1CollectedHeap* g1h,
- DirtyCardQueue* into_cset_dcq,
- G1ScanObjsDuringUpdateRSClosure* update_rs_cl) :
- _g1rs(g1h->g1_rem_set()), _into_cset_dcq(into_cset_dcq), _update_rs_cl(update_rs_cl)
+ G1RefineCardClosure(G1CollectedHeap* g1h, G1ScanObjsDuringUpdateRSClosure* update_rs_cl) :
+ _g1rs(g1h->g1_rem_set()), _update_rs_cl(update_rs_cl)
{}
bool do_card_ptr(jbyte* card_ptr, uint worker_i) {
@@ -467,24 +452,14 @@
// In this case worker_i should be the id of a GC worker thread.
assert(SafepointSynchronize::is_at_safepoint(), "not during an evacuation pause");
- if (_g1rs->refine_card_during_gc(card_ptr, _update_rs_cl)) {
- // 'card_ptr' contains references that point into the collection
- // set. We need to record the card in the DCQS
- // (_into_cset_dirty_card_queue_set)
- // that's used for that purpose.
- //
- // Enqueue the card
- _into_cset_dcq->enqueue(card_ptr);
- }
+ _g1rs->refine_card_during_gc(card_ptr, _update_rs_cl);
return true;
}
};
-void G1RemSet::update_rem_set(DirtyCardQueue* into_cset_dcq,
- G1ParScanThreadState* pss,
- uint worker_i) {
+void G1RemSet::update_rem_set(G1ParScanThreadState* pss, uint worker_i) {
G1ScanObjsDuringUpdateRSClosure update_rs_cl(_g1, pss, worker_i);
- G1RefineCardClosure refine_card_cl(_g1, into_cset_dcq, &update_rs_cl);
+ G1RefineCardClosure refine_card_cl(_g1, &update_rs_cl);
G1GCParPhaseTimesTracker x(_g1p->phase_times(), G1GCPhaseTimes::UpdateRS, worker_i);
if (G1HotCardCache::default_use_cache()) {
@@ -503,18 +478,7 @@
void G1RemSet::oops_into_collection_set_do(G1ParScanThreadState* pss,
CodeBlobClosure* heap_region_codeblobs,
uint worker_i) {
- // A DirtyCardQueue that is used to hold cards containing references
- // that point into the collection set. This DCQ is associated with a
- // special DirtyCardQueueSet (see g1CollectedHeap.hpp). Under normal
- // circumstances (i.e. the pause successfully completes), these cards
- // are just discarded (there's no need to update the RSets of regions
- // that were in the collection set - after the pause these regions
- // are wholly 'free' of live objects. In the event of an evacuation
- // failure the cards/buffers in this queue set are passed to the
- // DirtyCardQueueSet that is used to manage RSet updates
- DirtyCardQueue into_cset_dcq(&_into_cset_dirty_card_queue_set);
-
- update_rem_set(&into_cset_dcq, pss, worker_i);
+ update_rem_set(pss, worker_i);
scan_rem_set(pss, heap_region_codeblobs, worker_i);;
}
@@ -532,26 +496,6 @@
double start = os::elapsedTime();
_scan_state->clear_card_table(_g1->workers());
phase_times->record_clear_ct_time((os::elapsedTime() - start) * 1000.0);
-
- DirtyCardQueueSet& into_cset_dcqs = _into_cset_dirty_card_queue_set;
-
- if (_g1->evacuation_failed()) {
- double restore_remembered_set_start = os::elapsedTime();
-
- // Restore remembered sets for the regions pointing into the collection set.
- // We just need to transfer the completed buffers from the DirtyCardQueueSet
- // used to hold cards that contain references that point into the collection set
- // to the DCQS used to hold the deferred RS updates.
- _g1->dirty_card_queue_set().merge_bufferlists(&into_cset_dcqs);
- phase_times->record_evac_fail_restore_remsets((os::elapsedTime() - restore_remembered_set_start) * 1000.0);
- }
-
- // Free any completed buffers in the DirtyCardQueueSet used to hold cards
- // which contain references that point into the collection.
- _into_cset_dirty_card_queue_set.clear();
- assert(_into_cset_dirty_card_queue_set.completed_buffers_num() == 0,
- "all buffers should be freed");
- _into_cset_dirty_card_queue_set.clear_n_completed_buffers();
}
class G1ScrubRSClosure: public HeapRegionClosure {
@@ -736,7 +680,7 @@
}
}
-bool G1RemSet::refine_card_during_gc(jbyte* card_ptr,
+void G1RemSet::refine_card_during_gc(jbyte* card_ptr,
G1ScanObjsDuringUpdateRSClosure* update_rs_cl) {
assert(_g1->is_gc_active(), "Only call during GC");
@@ -745,9 +689,7 @@
// If the card is no longer dirty, nothing to do. This covers cards that were already
// scanned as parts of the remembered sets.
if (*card_ptr != CardTableModRefBS::dirty_card_val()) {
- // No need to return that this card contains refs that point
- // into the collection set.
- return false;
+ return;
}
// During GC we can immediately clean the card since we will not re-enqueue stale
@@ -762,7 +704,7 @@
HeapWord* scan_limit = _scan_state->scan_top(r->hrm_index());
if (scan_limit <= card_start) {
// If the card starts above the area in the region containing objects to scan, skip it.
- return false;
+ return;
}
// Don't use addr_for(card_ptr + 1) which can ask for
@@ -772,12 +714,8 @@
assert(!dirty_region.is_empty(), "sanity");
update_rs_cl->set_region(r);
- update_rs_cl->reset_has_refs_into_cset();
-
bool card_processed = r->oops_on_card_seq_iterate_careful<true>(dirty_region, update_rs_cl);
assert(card_processed, "must be");
-
- return update_rs_cl->has_refs_into_cset();
}
void G1RemSet::print_periodic_summary_info(const char* header, uint period_count) {
--- a/hotspot/src/share/vm/gc/g1/g1RemSet.hpp Fri Jul 14 14:04:57 2017 +0200
+++ b/hotspot/src/share/vm/gc/g1/g1RemSet.hpp Mon Jul 17 11:37:00 2017 +0200
@@ -59,12 +59,6 @@
G1RemSetSummary _prev_period_summary;
- // A DirtyCardQueueSet that is used to hold cards that contain
- // references into the current collection set. This is used to
- // update the remembered sets of the regions in the collection
- // set in the event of an evacuation failure.
- DirtyCardQueueSet _into_cset_dirty_card_queue_set;
-
// Scan all remembered sets of the collection set for references into the collection
// set.
void scan_rem_set(G1ParScanThreadState* pss,
@@ -73,7 +67,7 @@
// Flush remaining refinement buffers for cross-region references to either evacuate references
// into the collection set or update the remembered set.
- void update_rem_set(DirtyCardQueue* into_cset_dcq, G1ParScanThreadState* pss, uint worker_i);
+ void update_rem_set(G1ParScanThreadState* pss, uint worker_i);
G1CollectedHeap* _g1;
size_t _num_conc_refined_cards; // Number of cards refined concurrently to the mutator.
@@ -133,11 +127,8 @@
uint worker_i);
// Refine the card corresponding to "card_ptr", applying the given closure to
- // all references found. Returns "true" if the given card contains
- // oops that have references into the current collection set. Must only be
- // called during gc.
- bool refine_card_during_gc(jbyte* card_ptr,
- G1ScanObjsDuringUpdateRSClosure* update_rs_cl);
+ // all references found. Must only be called during gc.
+ void refine_card_during_gc(jbyte* card_ptr, G1ScanObjsDuringUpdateRSClosure* update_rs_cl);
// Print accumulated summary info from the start of the VM.
void print_summary_info();
--- a/hotspot/test/gc/g1/TestGCLogMessages.java Fri Jul 14 14:04:57 2017 +0200
+++ b/hotspot/test/gc/g1/TestGCLogMessages.java Mon Jul 17 11:37:00 2017 +0200
@@ -196,7 +196,6 @@
new LogMessageWithLevel("Evacuation Failure", Level.DEBUG),
new LogMessageWithLevel("Recalculate Used", Level.TRACE),
new LogMessageWithLevel("Remove Self Forwards", Level.TRACE),
- new LogMessageWithLevel("Restore RemSet", Level.TRACE),
};
private void testWithToSpaceExhaustionLogs() throws Exception {