--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.cpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.cpp Thu Oct 09 13:42:29 2014 +0200
@@ -1683,6 +1683,8 @@
int _failures;
bool _verbose;
+ HeapRegionClaimer _hrclaimer;
+
public:
G1ParVerifyFinalCountTask(G1CollectedHeap* g1h,
BitMap* region_bm, BitMap* card_bm,
@@ -1692,19 +1694,8 @@
_actual_region_bm(region_bm), _actual_card_bm(card_bm),
_expected_region_bm(expected_region_bm), _expected_card_bm(expected_card_bm),
_failures(0), _verbose(false),
- _n_workers(0) {
+ _n_workers(_g1h->workers()->active_workers()), _hrclaimer(_n_workers) {
assert(VerifyDuringGC, "don't call this otherwise");
-
- // Use the value already set as the number of active threads
- // in the call to run_task().
- if (G1CollectedHeap::use_parallel_gc_threads()) {
- assert( _g1h->workers()->active_workers() > 0,
- "Should have been previously set");
- _n_workers = _g1h->workers()->active_workers();
- } else {
- _n_workers = 1;
- }
-
assert(_expected_card_bm->size() == _actual_card_bm->size(), "sanity");
assert(_expected_region_bm->size() == _actual_region_bm->size(), "sanity");
@@ -1721,10 +1712,7 @@
_verbose);
if (G1CollectedHeap::use_parallel_gc_threads()) {
- _g1h->heap_region_par_iterate_chunked(&verify_cl,
- worker_id,
- _n_workers,
- HeapRegion::VerifyCountClaimValue);
+ _g1h->heap_region_par_iterate(&verify_cl, worker_id, &_hrclaimer);
} else {
_g1h->heap_region_iterate(&verify_cl);
}
@@ -1813,22 +1801,14 @@
BitMap* _actual_card_bm;
uint _n_workers;
+ HeapRegionClaimer _hrclaimer;
public:
G1ParFinalCountTask(G1CollectedHeap* g1h, BitMap* region_bm, BitMap* card_bm)
: AbstractGangTask("G1 final counting"),
_g1h(g1h), _cm(_g1h->concurrent_mark()),
_actual_region_bm(region_bm), _actual_card_bm(card_bm),
- _n_workers(0) {
- // Use the value already set as the number of active threads
- // in the call to run_task().
- if (G1CollectedHeap::use_parallel_gc_threads()) {
- assert( _g1h->workers()->active_workers() > 0,
- "Should have been previously set");
- _n_workers = _g1h->workers()->active_workers();
- } else {
- _n_workers = 1;
- }
+ _n_workers(_g1h->workers()->active_workers()), _hrclaimer(_n_workers) {
}
void work(uint worker_id) {
@@ -1839,10 +1819,7 @@
_actual_card_bm);
if (G1CollectedHeap::use_parallel_gc_threads()) {
- _g1h->heap_region_par_iterate_chunked(&final_update_cl,
- worker_id,
- _n_workers,
- HeapRegion::FinalCountClaimValue);
+ _g1h->heap_region_par_iterate(&final_update_cl, worker_id, &_hrclaimer);
} else {
_g1h->heap_region_iterate(&final_update_cl);
}
@@ -1929,12 +1906,12 @@
size_t _max_live_bytes;
size_t _freed_bytes;
FreeRegionList* _cleanup_list;
+ HeapRegionClaimer _hrclaimer;
public:
- G1ParNoteEndTask(G1CollectedHeap* g1h,
- FreeRegionList* cleanup_list) :
- AbstractGangTask("G1 note end"), _g1h(g1h),
- _max_live_bytes(0), _freed_bytes(0), _cleanup_list(cleanup_list) { }
+ G1ParNoteEndTask(G1CollectedHeap* g1h, FreeRegionList* cleanup_list, uint n_workers) :
+ AbstractGangTask("G1 note end"), _g1h(g1h), _max_live_bytes(0), _freed_bytes(0), _cleanup_list(cleanup_list), _hrclaimer(n_workers) {
+ }
void work(uint worker_id) {
double start = os::elapsedTime();
@@ -1943,9 +1920,7 @@
G1NoteEndOfConcMarkClosure g1_note_end(_g1h, &local_cleanup_list,
&hrrs_cleanup_task);
if (G1CollectedHeap::use_parallel_gc_threads()) {
- _g1h->heap_region_par_iterate_chunked(&g1_note_end, worker_id,
- _g1h->workers()->active_workers(),
- HeapRegion::NoteEndClaimValue);
+ _g1h->heap_region_par_iterate(&g1_note_end, worker_id, &_hrclaimer);
} else {
_g1h->heap_region_iterate(&g1_note_end);
}
@@ -1991,16 +1966,16 @@
G1RemSet* _g1rs;
BitMap* _region_bm;
BitMap* _card_bm;
+ HeapRegionClaimer _hrclaimer;
+
public:
- G1ParScrubRemSetTask(G1CollectedHeap* g1h,
- BitMap* region_bm, BitMap* card_bm) :
- AbstractGangTask("G1 ScrubRS"), _g1rs(g1h->g1_rem_set()),
- _region_bm(region_bm), _card_bm(card_bm) { }
+ G1ParScrubRemSetTask(G1CollectedHeap* g1h, BitMap* region_bm, BitMap* card_bm, uint n_workers) :
+ AbstractGangTask("G1 ScrubRS"), _g1rs(g1h->g1_rem_set()), _region_bm(region_bm), _card_bm(card_bm), _hrclaimer(n_workers) {
+ }
void work(uint worker_id) {
if (G1CollectedHeap::use_parallel_gc_threads()) {
- _g1rs->scrub_par(_region_bm, _card_bm, worker_id,
- HeapRegion::ScrubRemSetClaimValue);
+ _g1rs->scrub_par(_region_bm, _card_bm, worker_id, &_hrclaimer);
} else {
_g1rs->scrub(_region_bm, _card_bm);
}
@@ -2043,9 +2018,6 @@
G1ParFinalCountTask g1_par_count_task(g1h, &_region_bm, &_card_bm);
if (G1CollectedHeap::use_parallel_gc_threads()) {
- assert(g1h->check_heap_region_claim_values(HeapRegion::InitialClaimValue),
- "sanity check");
-
g1h->set_par_threads();
n_workers = g1h->n_par_threads();
assert(g1h->n_par_threads() == n_workers,
@@ -2053,9 +2025,6 @@
g1h->workers()->run_task(&g1_par_count_task);
// Done with the parallel phase so reset to 0.
g1h->set_par_threads(0);
-
- assert(g1h->check_heap_region_claim_values(HeapRegion::FinalCountClaimValue),
- "sanity check");
} else {
n_workers = 1;
g1_par_count_task.work(0);
@@ -2080,9 +2049,6 @@
g1h->workers()->run_task(&g1_par_verify_task);
// Done with the parallel phase so reset to 0.
g1h->set_par_threads(0);
-
- assert(g1h->check_heap_region_claim_values(HeapRegion::VerifyCountClaimValue),
- "sanity check");
} else {
g1_par_verify_task.work(0);
}
@@ -2108,14 +2074,11 @@
g1h->reset_gc_time_stamp();
// Note end of marking in all heap regions.
- G1ParNoteEndTask g1_par_note_end_task(g1h, &_cleanup_list);
+ G1ParNoteEndTask g1_par_note_end_task(g1h, &_cleanup_list, n_workers);
if (G1CollectedHeap::use_parallel_gc_threads()) {
g1h->set_par_threads((int)n_workers);
g1h->workers()->run_task(&g1_par_note_end_task);
g1h->set_par_threads(0);
-
- assert(g1h->check_heap_region_claim_values(HeapRegion::NoteEndClaimValue),
- "sanity check");
} else {
g1_par_note_end_task.work(0);
}
@@ -2132,15 +2095,11 @@
// regions.
if (G1ScrubRemSets) {
double rs_scrub_start = os::elapsedTime();
- G1ParScrubRemSetTask g1_par_scrub_rs_task(g1h, &_region_bm, &_card_bm);
+ G1ParScrubRemSetTask g1_par_scrub_rs_task(g1h, &_region_bm, &_card_bm, n_workers);
if (G1CollectedHeap::use_parallel_gc_threads()) {
g1h->set_par_threads((int)n_workers);
g1h->workers()->run_task(&g1_par_scrub_rs_task);
g1h->set_par_threads(0);
-
- assert(g1h->check_heap_region_claim_values(
- HeapRegion::ScrubRemSetClaimValue),
- "sanity check");
} else {
g1_par_scrub_rs_task.work(0);
}
@@ -3288,6 +3247,7 @@
BitMap* _cm_card_bm;
uint _max_worker_id;
int _active_workers;
+ HeapRegionClaimer _hrclaimer;
public:
G1AggregateCountDataTask(G1CollectedHeap* g1h,
@@ -3295,18 +3255,18 @@
BitMap* cm_card_bm,
uint max_worker_id,
int n_workers) :
- AbstractGangTask("Count Aggregation"),
- _g1h(g1h), _cm(cm), _cm_card_bm(cm_card_bm),
- _max_worker_id(max_worker_id),
- _active_workers(n_workers) { }
+ AbstractGangTask("Count Aggregation"),
+ _g1h(g1h), _cm(cm), _cm_card_bm(cm_card_bm),
+ _max_worker_id(max_worker_id),
+ _active_workers(n_workers),
+ _hrclaimer(_active_workers) {
+ }
void work(uint worker_id) {
AggregateCountDataHRClosure cl(_g1h, _cm_card_bm, _max_worker_id);
if (G1CollectedHeap::use_parallel_gc_threads()) {
- _g1h->heap_region_par_iterate_chunked(&cl, worker_id,
- _active_workers,
- HeapRegion::AggregateCountClaimValue);
+ _g1h->heap_region_par_iterate(&cl, worker_id, &_hrclaimer);
} else {
_g1h->heap_region_iterate(&cl);
}
@@ -3323,15 +3283,9 @@
_max_worker_id, n_workers);
if (G1CollectedHeap::use_parallel_gc_threads()) {
- assert(_g1h->check_heap_region_claim_values(HeapRegion::InitialClaimValue),
- "sanity check");
_g1h->set_par_threads(n_workers);
_g1h->workers()->run_task(&g1_par_agg_task);
_g1h->set_par_threads(0);
-
- assert(_g1h->check_heap_region_claim_values(HeapRegion::AggregateCountClaimValue),
- "sanity check");
- _g1h->reset_heap_region_claim_values();
} else {
g1_par_agg_task.work(0);
}
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp Thu Oct 09 13:42:29 2014 +0200
@@ -90,8 +90,8 @@
// Notes on implementation of parallelism in different tasks.
//
-// G1ParVerifyTask uses heap_region_par_iterate_chunked() for parallelism.
-// The number of GC workers is passed to heap_region_par_iterate_chunked().
+// G1ParVerifyTask uses heap_region_par_iterate() for parallelism.
+// The number of GC workers is passed to heap_region_par_iterate().
// It does use run_task() which sets _n_workers in the task.
// G1ParTask executes g1_process_roots() ->
// SharedHeap::process_roots() which calls eventually to
@@ -1215,17 +1215,15 @@
class ParRebuildRSTask: public AbstractGangTask {
G1CollectedHeap* _g1;
+ HeapRegionClaimer _hrclaimer;
+
public:
- ParRebuildRSTask(G1CollectedHeap* g1)
- : AbstractGangTask("ParRebuildRSTask"),
- _g1(g1)
- { }
+ ParRebuildRSTask(G1CollectedHeap* g1) :
+ AbstractGangTask("ParRebuildRSTask"), _g1(g1), _hrclaimer(g1->workers()->active_workers()) {}
void work(uint worker_id) {
RebuildRSOutOfRegionClosure rebuild_rs(_g1, worker_id);
- _g1->heap_region_par_iterate_chunked(&rebuild_rs, worker_id,
- _g1->workers()->active_workers(),
- HeapRegion::RebuildRSClaimValue);
+ _g1->heap_region_par_iterate(&rebuild_rs, worker_id, &_hrclaimer);
}
};
@@ -1455,8 +1453,6 @@
set_par_threads(n_workers);
ParRebuildRSTask rebuild_rs_task(this);
- assert(check_heap_region_claim_values(
- HeapRegion::InitialClaimValue), "sanity check");
assert(UseDynamicNumberOfGCThreads ||
workers()->active_workers() == workers()->total_workers(),
"Unless dynamic should use total workers");
@@ -1466,9 +1462,6 @@
set_par_threads(workers()->active_workers());
workers()->run_task(&rebuild_rs_task);
set_par_threads(0);
- assert(check_heap_region_claim_values(
- HeapRegion::RebuildRSClaimValue), "sanity check");
- reset_heap_region_claim_values();
} else {
RebuildRSOutOfRegionClosure rebuild_rs(this);
heap_region_iterate(&rebuild_rs);
@@ -2343,6 +2336,7 @@
case GCCause::_gc_locker: return GCLockerInvokesConcurrent;
case GCCause::_java_lang_system_gc: return ExplicitGCInvokesConcurrent;
case GCCause::_g1_humongous_allocation: return true;
+ case GCCause::_update_allocation_context_stats_inc: return true;
default: return false;
}
}
@@ -2633,110 +2627,11 @@
}
void
-G1CollectedHeap::heap_region_par_iterate_chunked(HeapRegionClosure* cl,
- uint worker_id,
- uint num_workers,
- jint claim_value) const {
- _hrm.par_iterate(cl, worker_id, num_workers, claim_value);
-}
-
-class ResetClaimValuesClosure: public HeapRegionClosure {
-public:
- bool doHeapRegion(HeapRegion* r) {
- r->set_claim_value(HeapRegion::InitialClaimValue);
- return false;
- }
-};
-
-void G1CollectedHeap::reset_heap_region_claim_values() {
- ResetClaimValuesClosure blk;
- heap_region_iterate(&blk);
-}
-
-void G1CollectedHeap::reset_cset_heap_region_claim_values() {
- ResetClaimValuesClosure blk;
- collection_set_iterate(&blk);
-}
-
-#ifdef ASSERT
-// This checks whether all regions in the heap have the correct claim
-// value. I also piggy-backed on this a check to ensure that the
-// humongous_start_region() information on "continues humongous"
-// regions is correct.
-
-class CheckClaimValuesClosure : public HeapRegionClosure {
-private:
- jint _claim_value;
- uint _failures;
- HeapRegion* _sh_region;
-
-public:
- CheckClaimValuesClosure(jint claim_value) :
- _claim_value(claim_value), _failures(0), _sh_region(NULL) { }
- bool doHeapRegion(HeapRegion* r) {
- if (r->claim_value() != _claim_value) {
- gclog_or_tty->print_cr("Region " HR_FORMAT ", "
- "claim value = %d, should be %d",
- HR_FORMAT_PARAMS(r),
- r->claim_value(), _claim_value);
- ++_failures;
- }
- if (!r->is_humongous()) {
- _sh_region = NULL;
- } else if (r->is_starts_humongous()) {
- _sh_region = r;
- } else if (r->is_continues_humongous()) {
- if (r->humongous_start_region() != _sh_region) {
- gclog_or_tty->print_cr("Region " HR_FORMAT ", "
- "HS = "PTR_FORMAT", should be "PTR_FORMAT,
- HR_FORMAT_PARAMS(r),
- r->humongous_start_region(),
- _sh_region);
- ++_failures;
- }
- }
- return false;
- }
- uint failures() { return _failures; }
-};
-
-bool G1CollectedHeap::check_heap_region_claim_values(jint claim_value) {
- CheckClaimValuesClosure cl(claim_value);
- heap_region_iterate(&cl);
- return cl.failures() == 0;
-}
-
-class CheckClaimValuesInCSetHRClosure: public HeapRegionClosure {
-private:
- jint _claim_value;
- uint _failures;
-
-public:
- CheckClaimValuesInCSetHRClosure(jint claim_value) :
- _claim_value(claim_value), _failures(0) { }
-
- uint failures() { return _failures; }
-
- bool doHeapRegion(HeapRegion* hr) {
- assert(hr->in_collection_set(), "how?");
- assert(!hr->is_humongous(), "H-region in CSet");
- if (hr->claim_value() != _claim_value) {
- gclog_or_tty->print_cr("CSet Region " HR_FORMAT ", "
- "claim value = %d, should be %d",
- HR_FORMAT_PARAMS(hr),
- hr->claim_value(), _claim_value);
- _failures += 1;
- }
- return false;
- }
-};
-
-bool G1CollectedHeap::check_cset_heap_region_claim_values(jint claim_value) {
- CheckClaimValuesInCSetHRClosure cl(claim_value);
- collection_set_iterate(&cl);
- return cl.failures() == 0;
-}
-#endif // ASSERT
+G1CollectedHeap::heap_region_par_iterate(HeapRegionClosure* cl,
+ uint worker_id,
+ HeapRegionClaimer *hrclaimer) const {
+ _hrm.par_iterate(cl, worker_id, hrclaimer);
+}
// Clear the cached CSet starting regions and (more importantly)
// the time stamps. Called when we reset the GC time stamp.
@@ -3251,19 +3146,21 @@
class G1ParVerifyTask: public AbstractGangTask {
private:
- G1CollectedHeap* _g1h;
- VerifyOption _vo;
- bool _failures;
+ G1CollectedHeap* _g1h;
+ VerifyOption _vo;
+ bool _failures;
+ HeapRegionClaimer _hrclaimer;
public:
// _vo == UsePrevMarking -> use "prev" marking information,
// _vo == UseNextMarking -> use "next" marking information,
// _vo == UseMarkWord -> use mark word from object header.
G1ParVerifyTask(G1CollectedHeap* g1h, VerifyOption vo) :
- AbstractGangTask("Parallel verify task"),
- _g1h(g1h),
- _vo(vo),
- _failures(false) { }
+ AbstractGangTask("Parallel verify task"),
+ _g1h(g1h),
+ _vo(vo),
+ _failures(false),
+ _hrclaimer(g1h->workers()->active_workers()) {}
bool failures() {
return _failures;
@@ -3272,9 +3169,7 @@
void work(uint worker_id) {
HandleMark hm;
VerifyRegionClosure blk(true, _vo);
- _g1h->heap_region_par_iterate_chunked(&blk, worker_id,
- _g1h->workers()->active_workers(),
- HeapRegion::ParVerifyClaimValue);
+ _g1h->heap_region_par_iterate(&blk, worker_id, &_hrclaimer);
if (blk.failures()) {
_failures = true;
}
@@ -3316,8 +3211,6 @@
if (!silent) { gclog_or_tty->print("HeapRegions "); }
if (GCParallelVerificationEnabled && ParallelGCThreads > 1) {
- assert(check_heap_region_claim_values(HeapRegion::InitialClaimValue),
- "sanity check");
G1ParVerifyTask task(this, vo);
assert(UseDynamicNumberOfGCThreads ||
@@ -3331,15 +3224,6 @@
failures = true;
}
- // Checks that the expected amount of parallel work was done.
- // The implication is that n_workers is > 0.
- assert(check_heap_region_claim_values(HeapRegion::ParVerifyClaimValue),
- "sanity check");
-
- reset_heap_region_claim_values();
-
- assert(check_heap_region_claim_values(HeapRegion::InitialClaimValue),
- "sanity check");
} else {
VerifyRegionClosure blk(false, vo);
heap_region_iterate(&blk);
@@ -3926,8 +3810,6 @@
}
assert(check_young_list_well_formed(), "young list should be well formed");
- assert(check_heap_region_claim_values(HeapRegion::InitialClaimValue),
- "sanity check");
// Don't dynamically change the number of GC threads this early. A value of
// 0 is used to indicate serial work. When parallel work is done,
@@ -4288,26 +4170,12 @@
}
void G1CollectedHeap::remove_self_forwarding_pointers() {
- assert(check_cset_heap_region_claim_values(HeapRegion::InitialClaimValue), "sanity");
-
double remove_self_forwards_start = os::elapsedTime();
+ set_par_threads();
G1ParRemoveSelfForwardPtrsTask rsfp_task(this);
-
- if (G1CollectedHeap::use_parallel_gc_threads()) {
- set_par_threads();
- workers()->run_task(&rsfp_task);
- set_par_threads(0);
- } else {
- rsfp_task.work(0);
- }
-
- assert(check_cset_heap_region_claim_values(HeapRegion::ParEvacFailureClaimValue), "sanity");
-
- // Reset the claim values in the regions in the collection set.
- reset_cset_heap_region_claim_values();
-
- assert(check_cset_heap_region_claim_values(HeapRegion::InitialClaimValue), "sanity");
+ workers()->run_task(&rsfp_task);
+ set_par_threads(0);
// Now restore saved marks, if any.
assert(_objs_with_preserved_marks.size() ==
@@ -5948,11 +5816,6 @@
purge_code_root_memory();
- if (g1_policy()->during_initial_mark_pause()) {
- // Reset the claim values set during marking the strong code roots
- reset_heap_region_claim_values();
- }
-
finalize_for_evac_failure();
if (evacuation_failed()) {
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp Thu Oct 09 13:42:29 2014 +0200
@@ -211,6 +211,7 @@
friend class G1FreeHumongousRegionClosure;
// Other related classes.
friend class G1MarkSweep;
+ friend class HeapRegionClaimer;
private:
// The one and only G1CollectedHeap, so static functions can find it.
@@ -1377,38 +1378,15 @@
inline HeapWord* bottom_addr_for_region(uint index) const;
- // Divide the heap region sequence into "chunks" of some size (the number
- // of regions divided by the number of parallel threads times some
- // overpartition factor, currently 4). Assumes that this will be called
- // in parallel by ParallelGCThreads worker threads with distinct worker
- // ids in the range [0..max(ParallelGCThreads-1, 1)], that all parallel
- // calls will use the same "claim_value", and that that claim value is
- // different from the claim_value of any heap region before the start of
- // the iteration. Applies "blk->doHeapRegion" to each of the regions, by
- // attempting to claim the first region in each chunk, and, if
- // successful, applying the closure to each region in the chunk (and
- // setting the claim value of the second and subsequent regions of the
- // chunk.) For now requires that "doHeapRegion" always returns "false",
- // i.e., that a closure never attempt to abort a traversal.
- void heap_region_par_iterate_chunked(HeapRegionClosure* cl,
- uint worker_id,
- uint num_workers,
- jint claim_value) const;
-
- // It resets all the region claim values to the default.
- void reset_heap_region_claim_values();
-
- // Resets the claim values of regions in the current
- // collection set to the default.
- void reset_cset_heap_region_claim_values();
-
-#ifdef ASSERT
- bool check_heap_region_claim_values(jint claim_value);
-
- // Same as the routine above but only checks regions in the
- // current collection set.
- bool check_cset_heap_region_claim_values(jint claim_value);
-#endif // ASSERT
+ // Iterate over the heap regions in parallel. Assumes that this will be called
+ // in parallel by ParallelGCThreads worker threads with distinct worker ids
+ // in the range [0..max(ParallelGCThreads-1, 1)]. Applies "blk->doHeapRegion"
+ // to each of the regions, by attempting to claim the region using the
+ // HeapRegionClaimer and, if successful, applying the closure to the claimed
+ // region.
+ void heap_region_par_iterate(HeapRegionClosure* cl,
+ uint worker_id,
+ HeapRegionClaimer* hrclaimer) const;
// Clear the cached cset start regions and (more importantly)
// the time stamps. Called when we reset the GC time stamp.
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp Thu Oct 09 13:42:29 2014 +0200
@@ -1598,19 +1598,17 @@
CollectionSetChooser* _hrSorted;
uint _chunk_size;
G1CollectedHeap* _g1;
+ HeapRegionClaimer _hrclaimer;
+
public:
- ParKnownGarbageTask(CollectionSetChooser* hrSorted, uint chunk_size) :
- AbstractGangTask("ParKnownGarbageTask"),
- _hrSorted(hrSorted), _chunk_size(chunk_size),
- _g1(G1CollectedHeap::heap()) { }
+ ParKnownGarbageTask(CollectionSetChooser* hrSorted, uint chunk_size, uint n_workers) :
+ AbstractGangTask("ParKnownGarbageTask"),
+ _hrSorted(hrSorted), _chunk_size(chunk_size),
+ _g1(G1CollectedHeap::heap()), _hrclaimer(n_workers) {}
void work(uint worker_id) {
ParKnownGarbageHRClosure parKnownGarbageCl(_hrSorted, _chunk_size);
-
- // Back to zero for the claim value.
- _g1->heap_region_par_iterate_chunked(&parKnownGarbageCl, worker_id,
- _g1->workers()->active_workers(),
- HeapRegion::InitialClaimValue);
+ _g1->heap_region_par_iterate(&parKnownGarbageCl, worker_id, &_hrclaimer);
}
};
@@ -1641,12 +1639,8 @@
}
_collectionSetChooser->prepare_for_par_region_addition(_g1->num_regions(),
WorkUnit);
- ParKnownGarbageTask parKnownGarbageTask(_collectionSetChooser,
- (int) WorkUnit);
+ ParKnownGarbageTask parKnownGarbageTask(_collectionSetChooser, WorkUnit, (uint) no_of_gc_threads);
_g1->workers()->run_task(&parKnownGarbageTask);
-
- assert(_g1->check_heap_region_claim_values(HeapRegion::InitialClaimValue),
- "sanity check");
} else {
KnownGarbageClosure knownGarbagecl(_collectionSetChooser);
_g1->heap_region_iterate(&knownGarbagecl);
--- a/hotspot/src/share/vm/gc_implementation/g1/g1EvacFailure.hpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1EvacFailure.hpp Thu Oct 09 13:42:29 2014 +0200
@@ -177,16 +177,18 @@
G1CollectedHeap* _g1h;
ConcurrentMark* _cm;
uint _worker_id;
+ HeapRegionClaimer* _hrclaimer;
DirtyCardQueue _dcq;
UpdateRSetDeferred _update_rset_cl;
public:
RemoveSelfForwardPtrHRClosure(G1CollectedHeap* g1h,
- uint worker_id) :
- _g1h(g1h), _dcq(&g1h->dirty_card_queue_set()), _update_rset_cl(g1h, &_dcq),
- _worker_id(worker_id), _cm(_g1h->concurrent_mark()) {
- }
+ uint worker_id,
+ HeapRegionClaimer* hrclaimer) :
+ _g1h(g1h), _dcq(&g1h->dirty_card_queue_set()), _update_rset_cl(g1h, &_dcq),
+ _worker_id(worker_id), _cm(_g1h->concurrent_mark()), _hrclaimer(hrclaimer) {
+ }
bool doHeapRegion(HeapRegion *hr) {
bool during_initial_mark = _g1h->g1_policy()->during_initial_mark_pause();
@@ -195,7 +197,7 @@
assert(!hr->is_humongous(), "sanity");
assert(hr->in_collection_set(), "bad CS");
- if (hr->claimHeapRegion(HeapRegion::ParEvacFailureClaimValue)) {
+ if (_hrclaimer->claim_region(hr->hrm_index())) {
if (hr->evacuation_failed()) {
RemoveSelfForwardPtrObjClosure rspc(_g1h, _cm, hr, &_update_rset_cl,
during_initial_mark,
@@ -233,14 +235,15 @@
class G1ParRemoveSelfForwardPtrsTask: public AbstractGangTask {
protected:
G1CollectedHeap* _g1h;
+ HeapRegionClaimer _hrclaimer;
public:
G1ParRemoveSelfForwardPtrsTask(G1CollectedHeap* g1h) :
- AbstractGangTask("G1 Remove Self-forwarding Pointers"),
- _g1h(g1h) { }
+ AbstractGangTask("G1 Remove Self-forwarding Pointers"), _g1h(g1h),
+ _hrclaimer(g1h->workers()->active_workers()) {}
void work(uint worker_id) {
- RemoveSelfForwardPtrHRClosure rsfp_cl(_g1h, worker_id);
+ RemoveSelfForwardPtrHRClosure rsfp_cl(_g1h, worker_id, &_hrclaimer);
HeapRegion* hr = _g1h->start_cset_region_for_worker(worker_id);
_g1h->collection_set_iterate_from(hr, &rsfp_cl);
--- a/hotspot/src/share/vm/gc_implementation/g1/g1RemSet.cpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1RemSet.cpp Thu Oct 09 13:42:29 2014 +0200
@@ -425,13 +425,9 @@
_g1->heap_region_iterate(&scrub_cl);
}
-void G1RemSet::scrub_par(BitMap* region_bm, BitMap* card_bm,
- uint worker_num, int claim_val) {
+void G1RemSet::scrub_par(BitMap* region_bm, BitMap* card_bm, uint worker_num, HeapRegionClaimer *hrclaimer) {
ScrubRSClosure scrub_cl(region_bm, card_bm);
- _g1->heap_region_par_iterate_chunked(&scrub_cl,
- worker_num,
- n_workers(),
- claim_val);
+ _g1->heap_region_par_iterate(&scrub_cl, worker_num, hrclaimer);
}
G1TriggerClosure::G1TriggerClosure() :
--- a/hotspot/src/share/vm/gc_implementation/g1/g1RemSet.hpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1RemSet.hpp Thu Oct 09 13:42:29 2014 +0200
@@ -128,10 +128,10 @@
void scrub(BitMap* region_bm, BitMap* card_bm);
// Like the above, but assumes is called in parallel: "worker_num" is the
- // parallel thread id of the current thread, and "claim_val" is the
- // value that should be used to claim heap regions.
+ // parallel thread id of the current thread, and "hrclaimer" is the shared
+ // HeapRegionClaimer that should be used to claim heap regions.
void scrub_par(BitMap* region_bm, BitMap* card_bm,
- uint worker_num, int claim_val);
+ uint worker_num, HeapRegionClaimer* hrclaimer);
// Refine the card corresponding to "card_ptr".
// If check_for_refs_into_cset is true, a true result is returned
--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegion.cpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegion.cpp Thu Oct 09 13:42:29 2014 +0200
@@ -217,7 +217,6 @@
} else {
hrrs->clear();
}
- _claimed = InitialClaimValue;
}
zero_marked_bytes();
@@ -294,17 +293,6 @@
_humongous_start_region = NULL;
}
-bool HeapRegion::claimHeapRegion(jint claimValue) {
- jint current = _claimed;
- if (current != claimValue) {
- jint res = Atomic::cmpxchg(claimValue, &_claimed, current);
- if (res == current) {
- return true;
- }
- }
- return false;
-}
-
HeapRegion::HeapRegion(uint hrm_index,
G1BlockOffsetSharedArray* sharedOffsetArray,
MemRegion mr) :
@@ -314,7 +302,7 @@
_humongous_start_region(NULL),
_in_collection_set(false),
_next_in_special_set(NULL),
- _claimed(InitialClaimValue), _evacuation_failed(false),
+ _evacuation_failed(false),
_prev_marked_bytes(0), _next_marked_bytes(0), _gc_efficiency(0.0),
_next_young_region(NULL),
_next_dirty_cards_region(NULL), _next(NULL), _prev(NULL),
--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegion.hpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegion.hpp Thu Oct 09 13:42:29 2014 +0200
@@ -254,9 +254,6 @@
HeapRegionSetBase* _containing_set;
#endif // ASSERT
- // For parallel heapRegion traversal.
- jint _claimed;
-
// We use concurrent marking to determine the amount of live data
// in each heap region.
size_t _prev_marked_bytes; // Bytes known to be live via last completed marking.
@@ -336,19 +333,6 @@
// up once during initialization time.
static void setup_heap_region_size(size_t initial_heap_size, size_t max_heap_size);
- enum ClaimValues {
- InitialClaimValue = 0,
- FinalCountClaimValue = 1,
- NoteEndClaimValue = 2,
- ScrubRemSetClaimValue = 3,
- ParVerifyClaimValue = 4,
- RebuildRSClaimValue = 5,
- ParEvacFailureClaimValue = 6,
- AggregateCountClaimValue = 7,
- VerifyCountClaimValue = 8,
- ParMarkRootClaimValue = 9
- };
-
// All allocated blocks are occupied by objects in a HeapRegion
bool block_is_obj(const HeapWord* p) const;
@@ -691,12 +675,6 @@
return (HeapWord *) obj >= next_top_at_mark_start();
}
- // For parallel heapRegion traversal.
- bool claimHeapRegion(int claimValue);
- jint claim_value() { return _claimed; }
- // Use this carefully: only when you're sure no one is claiming...
- void set_claim_value(int claimValue) { _claimed = claimValue; }
-
// Returns the "evacuation_failed" property of the region.
bool evacuation_failed() { return _evacuation_failed; }
--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegionManager.cpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegionManager.cpp Thu Oct 09 13:42:29 2014 +0200
@@ -260,20 +260,17 @@
return num_regions;
}
-uint HeapRegionManager::start_region_for_worker(uint worker_i, uint num_workers, uint num_regions) const {
- return num_regions * worker_i / num_workers;
-}
-
-void HeapRegionManager::par_iterate(HeapRegionClosure* blk, uint worker_id, uint num_workers, jint claim_value) const {
- const uint start_index = start_region_for_worker(worker_id, num_workers, _allocated_heapregions_length);
+void HeapRegionManager::par_iterate(HeapRegionClosure* blk, uint worker_id, HeapRegionClaimer* hrclaimer) const {
+ const uint start_index = hrclaimer->start_region_for_worker(worker_id);
// Every worker will actually look at all regions, skipping over regions that
// are currently not committed.
// This also (potentially) iterates over regions newly allocated during GC. This
// is no problem except for some extra work.
- for (uint count = 0; count < _allocated_heapregions_length; count++) {
- const uint index = (start_index + count) % _allocated_heapregions_length;
- assert(0 <= index && index < _allocated_heapregions_length, "sanity");
+ const uint n_regions = hrclaimer->n_regions();
+ for (uint count = 0; count < n_regions; count++) {
+ const uint index = (start_index + count) % n_regions;
+ assert(0 <= index && index < n_regions, "sanity");
// Skip over unavailable regions
if (!is_available(index)) {
continue;
@@ -282,11 +279,11 @@
// We'll ignore "continues humongous" regions (we'll process them
// when we come across their corresponding "start humongous"
// region) and regions already claimed.
- if (r->claim_value() == claim_value || r->is_continues_humongous()) {
+ if (hrclaimer->is_region_claimed(index) || r->is_continues_humongous()) {
continue;
}
// OK, try to claim it
- if (!r->claimHeapRegion(claim_value)) {
+ if (!hrclaimer->claim_region(index)) {
continue;
}
// Success!
@@ -306,13 +303,11 @@
assert(chr->humongous_start_region() == r,
err_msg("Must work on humongous continuation of the original start region "
PTR_FORMAT ", but is " PTR_FORMAT, p2i(r), p2i(chr)));
- assert(chr->claim_value() != claim_value,
+ assert(!hrclaimer->is_region_claimed(ch_index),
"Must not have been claimed yet because claiming of humongous continuation first claims the start region");
- bool claim_result = chr->claimHeapRegion(claim_value);
- // We should always be able to claim it; no one else should
- // be trying to claim this region.
- guarantee(claim_result, "We should always be able to claim the is_continues_humongous part of the humongous object");
+ // There's no need to actually claim the continues humongous region, but we can do it in an assert as an extra precaution.
+ assert(hrclaimer->claim_region(ch_index), "We should always be able to claim the continuesHumongous part of the humongous object");
bool res2 = blk->doHeapRegion(chr);
if (res2) {
@@ -445,3 +440,31 @@
}
#endif // PRODUCT
+HeapRegionClaimer::HeapRegionClaimer(uint n_workers) :
+ _n_workers(n_workers), _n_regions(G1CollectedHeap::heap()->_hrm._allocated_heapregions_length), _claims(NULL) {
+ assert(n_workers > 0, "Need at least one worker.");
+ _claims = NEW_C_HEAP_ARRAY(uint, _n_regions, mtGC);
+ memset(_claims, Unclaimed, sizeof(*_claims) * _n_regions);
+}
+
+HeapRegionClaimer::~HeapRegionClaimer() {
+ if (_claims != NULL) {
+ FREE_C_HEAP_ARRAY(uint, _claims, mtGC);
+ }
+}
+
+uint HeapRegionClaimer::start_region_for_worker(uint worker_id) const {
+ assert(worker_id < _n_workers, "Invalid worker_id.");
+ return _n_regions * worker_id / _n_workers;
+}
+
+bool HeapRegionClaimer::is_region_claimed(uint region_index) const {
+ assert(region_index < _n_regions, "Invalid index.");
+ return _claims[region_index] == Claimed;
+}
+
+bool HeapRegionClaimer::claim_region(uint region_index) {
+ assert(region_index < _n_regions, "Invalid index.");
+ uint old_val = Atomic::cmpxchg(Claimed, &_claims[region_index], Unclaimed);
+ return old_val == Unclaimed;
+}
--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegionManager.hpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegionManager.hpp Thu Oct 09 13:42:29 2014 +0200
@@ -31,6 +31,7 @@
class HeapRegion;
class HeapRegionClosure;
+class HeapRegionClaimer;
class FreeRegionList;
class G1HeapRegionTable : public G1BiasedMappedArray<HeapRegion*> {
@@ -66,6 +67,7 @@
class HeapRegionManager: public CHeapObj<mtGC> {
friend class VMStructs;
+ friend class HeapRegionClaimer;
G1HeapRegionTable _regions;
@@ -99,9 +101,6 @@
// Notify other data structures about change in the heap layout.
void update_committed_space(HeapWord* old_end, HeapWord* new_end);
- // Calculate the starting region for each worker during parallel iteration so
- // that they do not all start from the same region.
- uint start_region_for_worker(uint worker_i, uint num_workers, uint num_regions) const;
// Find a contiguous set of empty or uncommitted regions of length num and return
// the index of the first region or G1_NO_HRM_INDEX if the search was unsuccessful.
@@ -223,7 +222,7 @@
// terminating the iteration early if doHeapRegion() returns true.
void iterate(HeapRegionClosure* blk) const;
- void par_iterate(HeapRegionClosure* blk, uint worker_id, uint no_of_par_workers, jint claim_value) const;
+ void par_iterate(HeapRegionClosure* blk, uint worker_id, HeapRegionClaimer* hrclaimer) const;
// Uncommit up to num_regions_to_remove regions that are completely free.
// Return the actual number of uncommitted regions.
@@ -235,5 +234,33 @@
void verify_optional() PRODUCT_RETURN;
};
+// The HeapRegionClaimer is used during parallel iteration over heap regions,
+// allowing workers to claim heap regions, gaining exclusive rights to these regions.
+class HeapRegionClaimer : public StackObj {
+ uint _n_workers;
+ uint _n_regions;
+ uint* _claims;
+
+ static const uint Unclaimed = 0;
+ static const uint Claimed = 1;
+
+ public:
+ HeapRegionClaimer(uint n_workers);
+ ~HeapRegionClaimer();
+
+ inline uint n_regions() const {
+ return _n_regions;
+ }
+
+ // Calculate the starting region for given worker so
+ // that they do not all start from the same region.
+ uint start_region_for_worker(uint worker_id) const;
+
+ // Check if region has been claimed with this HRClaimer.
+ bool is_region_claimed(uint region_index) const;
+
+ // Claim the given region, returns true if successfully claimed.
+ bool claim_region(uint region_index);
+};
#endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONMANAGER_HPP
--- a/hotspot/src/share/vm/gc_implementation/g1/vm_operations_g1.cpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_implementation/g1/vm_operations_g1.cpp Thu Oct 09 13:42:29 2014 +0200
@@ -95,8 +95,9 @@
assert(!_should_initiate_conc_mark ||
((_gc_cause == GCCause::_gc_locker && GCLockerInvokesConcurrent) ||
(_gc_cause == GCCause::_java_lang_system_gc && ExplicitGCInvokesConcurrent) ||
- _gc_cause == GCCause::_g1_humongous_allocation),
- "only a GC locker, a System.gc() or a hum allocation induced GC should start a cycle");
+ _gc_cause == GCCause::_g1_humongous_allocation ||
+ _gc_cause == GCCause::_update_allocation_context_stats_inc),
+ "only a GC locker, a System.gc(), stats update or a hum allocation induced GC should start a cycle");
if (_word_size > 0) {
// An allocation has been requested. So, try to do that first.
--- a/hotspot/src/share/vm/gc_interface/gcCause.cpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_interface/gcCause.cpp Thu Oct 09 13:42:29 2014 +0200
@@ -54,7 +54,8 @@
case _wb_young_gc:
return "WhiteBox Initiated Young GC";
- case _update_allocation_context_stats:
+ case _update_allocation_context_stats_inc:
+ case _update_allocation_context_stats_full:
return "Update Allocation Context Stats";
case _no_gc:
--- a/hotspot/src/share/vm/gc_interface/gcCause.hpp Fri Oct 03 13:56:18 2014 -0700
+++ b/hotspot/src/share/vm/gc_interface/gcCause.hpp Thu Oct 09 13:42:29 2014 +0200
@@ -47,7 +47,8 @@
_heap_inspection,
_heap_dump,
_wb_young_gc,
- _update_allocation_context_stats,
+ _update_allocation_context_stats_inc,
+ _update_allocation_context_stats_full,
/* implementation independent, but reserved for GC use */
_no_gc,