1 /*
2 * Copyright (c) 2001, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "gc/parallel/objectStartArray.inline.hpp"
26 #include "gc/parallel/parallelArguments.hpp"
27 #include "gc/parallel/parallelInitLogger.hpp"
28 #include "gc/parallel/parallelScavengeHeap.inline.hpp"
29 #include "gc/parallel/psAdaptiveSizePolicy.hpp"
30 #include "gc/parallel/psMemoryPool.hpp"
31 #include "gc/parallel/psParallelCompact.inline.hpp"
32 #include "gc/parallel/psPromotionManager.hpp"
33 #include "gc/parallel/psScavenge.hpp"
34 #include "gc/parallel/psVMOperations.hpp"
35 #include "gc/shared/fullGCForwarding.inline.hpp"
36 #include "gc/shared/gcHeapSummary.hpp"
37 #include "gc/shared/gcLocker.inline.hpp"
38 #include "gc/shared/gcWhen.hpp"
39 #include "gc/shared/genArguments.hpp"
40 #include "gc/shared/locationPrinter.inline.hpp"
41 #include "gc/shared/scavengableNMethods.hpp"
42 #include "gc/shared/suspendibleThreadSet.hpp"
43 #include "logging/log.hpp"
44 #include "memory/iterator.hpp"
45 #include "memory/metaspaceCounters.hpp"
46 #include "memory/metaspaceUtils.hpp"
47 #include "memory/reservedSpace.hpp"
48 #include "memory/universe.hpp"
49 #include "oops/oop.inline.hpp"
50 #include "runtime/cpuTimeCounters.hpp"
51 #include "runtime/handles.inline.hpp"
52 #include "runtime/java.hpp"
53 #include "runtime/vmThread.hpp"
54 #include "services/memoryManager.hpp"
55 #include "utilities/macros.hpp"
56 #include "utilities/vmError.hpp"
57
58 PSYoungGen* ParallelScavengeHeap::_young_gen = nullptr;
59 PSOldGen* ParallelScavengeHeap::_old_gen = nullptr;
60 PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = nullptr;
61 PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = nullptr;
62
63 jint ParallelScavengeHeap::initialize() {
64 const size_t reserved_heap_size = ParallelArguments::heap_reserved_size_bytes();
65
66 ReservedHeapSpace heap_rs = Universe::reserve_heap(reserved_heap_size, HeapAlignment);
67
68 trace_actual_reserved_page_size(reserved_heap_size, heap_rs);
69
70 initialize_reserved_region(heap_rs);
71 // Layout the reserved space for the generations.
72 ReservedSpace old_rs = heap_rs.first_part(MaxOldSize, SpaceAlignment);
73 ReservedSpace young_rs = heap_rs.last_part(MaxOldSize, SpaceAlignment);
74 assert(young_rs.size() == MaxNewSize, "Didn't reserve all of the heap");
75
76 PSCardTable* card_table = new PSCardTable(_reserved);
77 card_table->initialize(old_rs.base(), young_rs.base());
78
79 CardTableBarrierSet* const barrier_set = new CardTableBarrierSet(card_table);
80 barrier_set->initialize();
81 BarrierSet::set_barrier_set(barrier_set);
82
83 // Set up WorkerThreads
84 _workers.initialize_workers();
85
86 // Create and initialize the generations.
87 _young_gen = new PSYoungGen(
88 young_rs,
89 NewSize,
90 MinNewSize,
91 MaxNewSize);
92 _old_gen = new PSOldGen(
93 old_rs,
94 OldSize,
95 MinOldSize,
96 MaxOldSize);
97
98 assert(young_gen()->max_gen_size() == young_rs.size(),"Consistency check");
99 assert(old_gen()->max_gen_size() == old_rs.size(), "Consistency check");
100
101 double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0;
102
103 const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes();
104 const size_t old_capacity = _old_gen->capacity_in_bytes();
105 const size_t initial_promo_size = MIN2(eden_capacity, old_capacity);
106 _size_policy =
107 new PSAdaptiveSizePolicy(eden_capacity,
108 initial_promo_size,
109 young_gen()->to_space()->capacity_in_bytes(),
110 SpaceAlignment,
111 max_gc_pause_sec,
112 GCTimeRatio
113 );
114
115 assert((old_gen()->virtual_space()->high_boundary() ==
116 young_gen()->virtual_space()->low_boundary()),
117 "Boundaries must meet");
118 // initialize the policy counters - 2 collectors, 2 generations
119 _gc_policy_counters =
120 new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 2, _size_policy);
121
122 if (!PSParallelCompact::initialize_aux_data()) {
123 return JNI_ENOMEM;
124 }
125
126 // Create CPU time counter
127 CPUTimeCounters::create_counter(CPUTimeGroups::CPUTimeType::gc_parallel_workers);
128
129 ParallelInitLogger::print();
130
131 FullGCForwarding::initialize(_reserved);
132
133 return JNI_OK;
134 }
135
136 void ParallelScavengeHeap::initialize_serviceability() {
137
138 _eden_pool = new EdenMutableSpacePool(_young_gen,
139 _young_gen->eden_space(),
140 "PS Eden Space",
141 false /* support_usage_threshold */);
142
143 _survivor_pool = new SurvivorMutableSpacePool(_young_gen,
144 "PS Survivor Space",
145 false /* support_usage_threshold */);
146
147 _old_pool = new PSGenerationPool(_old_gen,
148 "PS Old Gen",
149 true /* support_usage_threshold */);
150
151 _young_manager = new GCMemoryManager("PS Scavenge");
152 _old_manager = new GCMemoryManager("PS MarkSweep");
153
154 _old_manager->add_pool(_eden_pool);
155 _old_manager->add_pool(_survivor_pool);
156 _old_manager->add_pool(_old_pool);
157
158 _young_manager->add_pool(_eden_pool);
159 _young_manager->add_pool(_survivor_pool);
160
161 }
162
163 void ParallelScavengeHeap::safepoint_synchronize_begin() {
164 if (UseStringDeduplication) {
165 SuspendibleThreadSet::synchronize();
166 }
167 }
168
169 void ParallelScavengeHeap::safepoint_synchronize_end() {
170 if (UseStringDeduplication) {
171 SuspendibleThreadSet::desynchronize();
172 }
173 }
174 class PSIsScavengable : public BoolObjectClosure {
175 bool do_object_b(oop obj) {
176 return ParallelScavengeHeap::heap()->is_in_young(obj);
177 }
178 };
179
180 static PSIsScavengable _is_scavengable;
181
182 void ParallelScavengeHeap::post_initialize() {
183 CollectedHeap::post_initialize();
184 // Need to init the tenuring threshold
185 PSScavenge::initialize();
186 PSParallelCompact::post_initialize();
187 PSPromotionManager::initialize();
188
189 ScavengableNMethods::initialize(&_is_scavengable);
190 GCLocker::initialize();
191 }
192
193 void ParallelScavengeHeap::update_counters() {
194 young_gen()->update_counters();
195 old_gen()->update_counters();
196 MetaspaceCounters::update_performance_counters();
197 update_parallel_worker_threads_cpu_time();
198 }
199
200 size_t ParallelScavengeHeap::capacity() const {
201 size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes();
202 return value;
203 }
204
205 size_t ParallelScavengeHeap::used() const {
206 size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes();
207 return value;
208 }
209
210 size_t ParallelScavengeHeap::max_capacity() const {
211 size_t estimated = reserved_region().byte_size();
212 if (UseAdaptiveSizePolicy) {
213 estimated -= _size_policy->max_survivor_size(young_gen()->max_gen_size());
214 } else {
215 estimated -= young_gen()->to_space()->capacity_in_bytes();
216 }
217 return MAX2(estimated, capacity());
218 }
219
220 bool ParallelScavengeHeap::is_in(const void* p) const {
221 return young_gen()->is_in(p) || old_gen()->is_in(p);
222 }
223
224 bool ParallelScavengeHeap::is_in_reserved(const void* p) const {
225 return young_gen()->is_in_reserved(p) || old_gen()->is_in_reserved(p);
226 }
227
228 bool ParallelScavengeHeap::requires_barriers(stackChunkOop p) const {
229 return !is_in_young(p);
230 }
231
232 // There are two levels of allocation policy here.
233 //
234 // When an allocation request fails, the requesting thread must invoke a VM
235 // operation, transfer control to the VM thread, and await the results of a
236 // garbage collection. That is quite expensive, and we should avoid doing it
237 // multiple times if possible.
238 //
239 // To accomplish this, we have a basic allocation policy, and also a
240 // failed allocation policy.
241 //
242 // The basic allocation policy controls how you allocate memory without
243 // attempting garbage collection. It is okay to grab locks and
244 // expand the heap, if that can be done without coming to a safepoint.
245 // It is likely that the basic allocation policy will not be very
246 // aggressive.
247 //
248 // The failed allocation policy is invoked from the VM thread after
249 // the basic allocation policy is unable to satisfy a mem_allocate
250 // request. This policy needs to cover the entire range of collection,
251 // heap expansion, and out-of-memory conditions. It should make every
252 // attempt to allocate the requested memory.
253
254 // Basic allocation policy. Should never be called at a safepoint, or
255 // from the VM thread.
256 //
257 // This method must handle cases where many mem_allocate requests fail
258 // simultaneously. When that happens, only one VM operation will succeed,
259 // and the rest will not be executed. For that reason, this method loops
260 // during failed allocation attempts. If the java heap becomes exhausted,
261 // we rely on the size_policy object to force a bail out.
262 HeapWord* ParallelScavengeHeap::mem_allocate(size_t size,
263 bool* gc_overhead_limit_was_exceeded) {
264 assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint");
265 assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread");
266 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
267
268 bool is_tlab = false;
269 return mem_allocate_work(size, is_tlab, gc_overhead_limit_was_exceeded);
270 }
271
272 HeapWord* ParallelScavengeHeap::mem_allocate_work(size_t size,
273 bool is_tlab,
274 bool* gc_overhead_limit_was_exceeded) {
275
276 // In general gc_overhead_limit_was_exceeded should be false so
277 // set it so here and reset it to true only if the gc time
278 // limit is being exceeded as checked below.
279 *gc_overhead_limit_was_exceeded = false;
280
281 HeapWord* result = young_gen()->allocate(size);
282
283 uint loop_count = 0;
284 uint gc_count = 0;
285
286 while (result == nullptr) {
287 // We don't want to have multiple collections for a single filled generation.
288 // To prevent this, each thread tracks the total_collections() value, and if
289 // the count has changed, does not do a new collection.
290 //
291 // The collection count must be read only while holding the heap lock. VM
292 // operations also hold the heap lock during collections. There is a lock
293 // contention case where thread A blocks waiting on the Heap_lock, while
294 // thread B is holding it doing a collection. When thread A gets the lock,
295 // the collection count has already changed. To prevent duplicate collections,
296 // The policy MUST attempt allocations during the same period it reads the
297 // total_collections() value!
298 {
299 MutexLocker ml(Heap_lock);
300 gc_count = total_collections();
301
302 result = young_gen()->allocate(size);
303 if (result != nullptr) {
304 return result;
305 }
306
307 // If certain conditions hold, try allocating from the old gen.
308 if (!is_tlab) {
309 result = mem_allocate_old_gen(size);
310 if (result != nullptr) {
311 return result;
312 }
313 }
314 }
315
316 assert(result == nullptr, "inv");
317 {
318 VM_ParallelCollectForAllocation op(size, is_tlab, gc_count);
319 VMThread::execute(&op);
320
321 // Did the VM operation execute? If so, return the result directly.
322 // This prevents us from looping until time out on requests that can
323 // not be satisfied.
324 if (op.gc_succeeded()) {
325 assert(is_in_or_null(op.result()), "result not in heap");
326
327 // Exit the loop if the gc time limit has been exceeded.
328 // The allocation must have failed above ("result" guarding
329 // this path is null) and the most recent collection has exceeded the
330 // gc overhead limit (although enough may have been collected to
331 // satisfy the allocation). Exit the loop so that an out-of-memory
332 // will be thrown (return a null ignoring the contents of
333 // op.result()),
334 // but clear gc_overhead_limit_exceeded so that the next collection
335 // starts with a clean slate (i.e., forgets about previous overhead
336 // excesses). Fill op.result() with a filler object so that the
337 // heap remains parsable.
338 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded();
339 const bool softrefs_clear = soft_ref_policy()->all_soft_refs_clear();
340
341 if (limit_exceeded && softrefs_clear) {
342 *gc_overhead_limit_was_exceeded = true;
343 size_policy()->set_gc_overhead_limit_exceeded(false);
344 log_trace(gc)("ParallelScavengeHeap::mem_allocate: return null because gc_overhead_limit_exceeded is set");
345 if (op.result() != nullptr) {
346 CollectedHeap::fill_with_object(op.result(), size);
347 }
348 return nullptr;
349 }
350
351 return op.result();
352 }
353 }
354
355 // The policy object will prevent us from looping forever. If the
356 // time spent in gc crosses a threshold, we will bail out.
357 loop_count++;
358 if ((result == nullptr) && (QueuedAllocationWarningCount > 0) &&
359 (loop_count % QueuedAllocationWarningCount == 0)) {
360 log_warning(gc)("ParallelScavengeHeap::mem_allocate retries %d times", loop_count);
361 log_warning(gc)("\tsize=%zu", size);
362 }
363 }
364
365 return result;
366 }
367
368 HeapWord* ParallelScavengeHeap::allocate_old_gen_and_record(size_t size) {
369 assert_locked_or_safepoint(Heap_lock);
370 HeapWord* res = old_gen()->allocate(size);
371 if (res != nullptr) {
372 _size_policy->tenured_allocation(size * HeapWordSize);
373 }
374 return res;
375 }
376
377 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) {
378 if (!should_alloc_in_eden(size)) {
379 // Size is too big for eden.
380 return allocate_old_gen_and_record(size);
381 }
382
383 return nullptr;
384 }
385
386 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) {
387 PSParallelCompact::invoke(clear_all_soft_refs);
388 }
389
390 HeapWord* ParallelScavengeHeap::expand_heap_and_allocate(size_t size, bool is_tlab) {
391 HeapWord* result = nullptr;
392
393 result = young_gen()->allocate(size);
394 if (result == nullptr && !is_tlab) {
395 result = old_gen()->expand_and_allocate(size);
396 }
397 return result; // Could be null if we are out of space.
398 }
399
400 HeapWord* ParallelScavengeHeap::satisfy_failed_allocation(size_t size, bool is_tlab) {
401 assert(size != 0, "precondition");
402
403 HeapWord* result = nullptr;
404
405 // If young-gen can handle this allocation, attempt young-gc firstly.
406 bool should_run_young_gc = is_tlab || should_alloc_in_eden(size);
407 collect_at_safepoint(!should_run_young_gc);
408
409 result = expand_heap_and_allocate(size, is_tlab);
410 if (result != nullptr) {
411 return result;
412 }
413
414 // If we reach this point, we're really out of memory. Try every trick
415 // we can to reclaim memory. Force collection of soft references. Force
416 // a complete compaction of the heap. Any additional methods for finding
417 // free memory should be here, especially if they are expensive. If this
418 // attempt fails, an OOM exception will be thrown.
419 {
420 // Make sure the heap is fully compacted
421 uintx old_interval = HeapMaximumCompactionInterval;
422 HeapMaximumCompactionInterval = 0;
423
424 const bool clear_all_soft_refs = true;
425 PSParallelCompact::invoke(clear_all_soft_refs);
426
427 // Restore
428 HeapMaximumCompactionInterval = old_interval;
429 }
430
431 result = expand_heap_and_allocate(size, is_tlab);
432 if (result != nullptr) {
433 return result;
434 }
435
436 // What else? We might try synchronous finalization later. If the total
437 // space available is large enough for the allocation, then a more
438 // complete compaction phase than we've tried so far might be
439 // appropriate.
440 return nullptr;
441 }
442
443
444 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) {
445 CollectedHeap::ensure_parsability(retire_tlabs);
446 young_gen()->eden_space()->ensure_parsability();
447 }
448
449 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const {
450 return young_gen()->eden_space()->tlab_capacity(thr);
451 }
452
453 size_t ParallelScavengeHeap::tlab_used(Thread* thr) const {
454 return young_gen()->eden_space()->tlab_used(thr);
455 }
456
457 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const {
458 return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr);
459 }
460
461 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size) {
462 bool dummy;
463 HeapWord* result = mem_allocate_work(requested_size /* size */,
464 true /* is_tlab */,
465 &dummy);
466 if (result != nullptr) {
467 *actual_size = requested_size;
468 }
469
470 return result;
471 }
472
473 void ParallelScavengeHeap::resize_all_tlabs() {
474 CollectedHeap::resize_all_tlabs();
475 }
476
477 void ParallelScavengeHeap::prune_scavengable_nmethods() {
478 ScavengableNMethods::prune_nmethods_not_into_young();
479 }
480
481 void ParallelScavengeHeap::prune_unlinked_nmethods() {
482 ScavengableNMethods::prune_unlinked_nmethods();
483 }
484
485 void ParallelScavengeHeap::collect(GCCause::Cause cause) {
486 assert(!Heap_lock->owned_by_self(),
487 "this thread should not own the Heap_lock");
488
489 uint gc_count = 0;
490 uint full_gc_count = 0;
491 {
492 MutexLocker ml(Heap_lock);
493 // This value is guarded by the Heap_lock
494 gc_count = total_collections();
495 full_gc_count = total_full_collections();
496 }
497
498 VM_ParallelGCCollect op(gc_count, full_gc_count, cause);
499 VMThread::execute(&op);
500 }
501
502 bool ParallelScavengeHeap::must_clear_all_soft_refs() {
503 return _gc_cause == GCCause::_metadata_GC_clear_soft_refs ||
504 _gc_cause == GCCause::_wb_full_gc;
505 }
506
507 void ParallelScavengeHeap::collect_at_safepoint(bool full) {
508 assert(!GCLocker::is_active(), "precondition");
509 bool clear_soft_refs = must_clear_all_soft_refs();
510
511 if (!full) {
512 bool success = PSScavenge::invoke(clear_soft_refs);
513 if (success) {
514 return;
515 }
516 // Upgrade to Full-GC if young-gc fails
517 }
518 PSParallelCompact::invoke(clear_soft_refs);
519 }
520
521 void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) {
522 young_gen()->object_iterate(cl);
523 old_gen()->object_iterate(cl);
524 }
525
526 // The HeapBlockClaimer is used during parallel iteration over the heap,
527 // allowing workers to claim heap areas ("blocks"), gaining exclusive rights to these.
528 // The eden and survivor spaces are treated as single blocks as it is hard to divide
529 // these spaces.
530 // The old space is divided into fixed-size blocks.
531 class HeapBlockClaimer : public StackObj {
532 size_t _claimed_index;
533
534 public:
535 static const size_t InvalidIndex = SIZE_MAX;
536 static const size_t EdenIndex = 0;
537 static const size_t SurvivorIndex = 1;
538 static const size_t NumNonOldGenClaims = 2;
539
540 HeapBlockClaimer() : _claimed_index(EdenIndex) { }
541 // Claim the block and get the block index.
542 size_t claim_and_get_block() {
543 size_t block_index;
544 block_index = Atomic::fetch_then_add(&_claimed_index, 1u);
545
546 PSOldGen* old_gen = ParallelScavengeHeap::heap()->old_gen();
547 size_t num_claims = old_gen->num_iterable_blocks() + NumNonOldGenClaims;
548
549 return block_index < num_claims ? block_index : InvalidIndex;
550 }
551 };
552
553 void ParallelScavengeHeap::object_iterate_parallel(ObjectClosure* cl,
554 HeapBlockClaimer* claimer) {
555 size_t block_index = claimer->claim_and_get_block();
556 // Iterate until all blocks are claimed
557 if (block_index == HeapBlockClaimer::EdenIndex) {
558 young_gen()->eden_space()->object_iterate(cl);
559 block_index = claimer->claim_and_get_block();
560 }
561 if (block_index == HeapBlockClaimer::SurvivorIndex) {
562 young_gen()->from_space()->object_iterate(cl);
563 young_gen()->to_space()->object_iterate(cl);
564 block_index = claimer->claim_and_get_block();
565 }
566 while (block_index != HeapBlockClaimer::InvalidIndex) {
567 old_gen()->object_iterate_block(cl, block_index - HeapBlockClaimer::NumNonOldGenClaims);
568 block_index = claimer->claim_and_get_block();
569 }
570 }
571
572 class PSScavengeParallelObjectIterator : public ParallelObjectIteratorImpl {
573 private:
574 ParallelScavengeHeap* _heap;
575 HeapBlockClaimer _claimer;
576
577 public:
578 PSScavengeParallelObjectIterator() :
579 _heap(ParallelScavengeHeap::heap()),
580 _claimer() {}
581
582 virtual void object_iterate(ObjectClosure* cl, uint worker_id) {
583 _heap->object_iterate_parallel(cl, &_claimer);
584 }
585 };
586
587 ParallelObjectIteratorImpl* ParallelScavengeHeap::parallel_object_iterator(uint thread_num) {
588 return new PSScavengeParallelObjectIterator();
589 }
590
591 HeapWord* ParallelScavengeHeap::block_start(const void* addr) const {
592 if (young_gen()->is_in_reserved(addr)) {
593 assert(young_gen()->is_in(addr),
594 "addr should be in allocated part of young gen");
595 // called from os::print_location by find or VMError
596 if (DebuggingContext::is_enabled() || VMError::is_error_reported()) {
597 return nullptr;
598 }
599 Unimplemented();
600 } else if (old_gen()->is_in_reserved(addr)) {
601 assert(old_gen()->is_in(addr),
602 "addr should be in allocated part of old gen");
603 return old_gen()->start_array()->object_start((HeapWord*)addr);
604 }
605 return nullptr;
606 }
607
608 bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const {
609 return block_start(addr) == addr;
610 }
611
612 void ParallelScavengeHeap::prepare_for_verify() {
613 ensure_parsability(false); // no need to retire TLABs for verification
614 }
615
616 PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() {
617 PSOldGen* old = old_gen();
618 HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr();
619 HeapWord* old_reserved_start = old->reserved().start();
620 HeapWord* old_reserved_end = old->reserved().end();
621 VirtualSpaceSummary old_summary(old_reserved_start, old_committed_end, old_reserved_end);
622 SpaceSummary old_space(old_reserved_start, old_committed_end, old->used_in_bytes());
623
624 PSYoungGen* young = young_gen();
625 VirtualSpaceSummary young_summary(young->reserved().start(),
626 (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end());
627
628 MutableSpace* eden = young_gen()->eden_space();
629 SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes());
630
631 MutableSpace* from = young_gen()->from_space();
632 SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes());
633
634 MutableSpace* to = young_gen()->to_space();
635 SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes());
636
637 VirtualSpaceSummary heap_summary = create_heap_space_summary();
638 return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space);
639 }
640
641 bool ParallelScavengeHeap::print_location(outputStream* st, void* addr) const {
642 return BlockLocationPrinter<ParallelScavengeHeap>::print_location(st, addr);
643 }
644
645 void ParallelScavengeHeap::print_heap_on(outputStream* st) const {
646 if (young_gen() != nullptr) {
647 young_gen()->print_on(st);
648 }
649 if (old_gen() != nullptr) {
650 old_gen()->print_on(st);
651 }
652 }
653
654 void ParallelScavengeHeap::print_gc_on(outputStream* st) const {
655 BarrierSet* bs = BarrierSet::barrier_set();
656 if (bs != nullptr) {
657 bs->print_on(st);
658 }
659 st->cr();
660
661 PSParallelCompact::print_on(st);
662 }
663
664 void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const {
665 ParallelScavengeHeap::heap()->workers().threads_do(tc);
666 }
667
668 void ParallelScavengeHeap::print_tracing_info() const {
669 AdaptiveSizePolicyOutput::print();
670 log_debug(gc, heap, exit)("Accumulated young generation GC time %3.7f secs", PSScavenge::accumulated_time()->seconds());
671 log_debug(gc, heap, exit)("Accumulated old generation GC time %3.7f secs", PSParallelCompact::accumulated_time()->seconds());
672 }
673
674 PreGenGCValues ParallelScavengeHeap::get_pre_gc_values() const {
675 const PSYoungGen* const young = young_gen();
676 const MutableSpace* const eden = young->eden_space();
677 const MutableSpace* const from = young->from_space();
678 const PSOldGen* const old = old_gen();
679
680 return PreGenGCValues(young->used_in_bytes(),
681 young->capacity_in_bytes(),
682 eden->used_in_bytes(),
683 eden->capacity_in_bytes(),
684 from->used_in_bytes(),
685 from->capacity_in_bytes(),
686 old->used_in_bytes(),
687 old->capacity_in_bytes());
688 }
689
690 void ParallelScavengeHeap::print_heap_change(const PreGenGCValues& pre_gc_values) const {
691 const PSYoungGen* const young = young_gen();
692 const MutableSpace* const eden = young->eden_space();
693 const MutableSpace* const from = young->from_space();
694 const PSOldGen* const old = old_gen();
695
696 log_info(gc, heap)(HEAP_CHANGE_FORMAT" "
697 HEAP_CHANGE_FORMAT" "
698 HEAP_CHANGE_FORMAT,
699 HEAP_CHANGE_FORMAT_ARGS(young->name(),
700 pre_gc_values.young_gen_used(),
701 pre_gc_values.young_gen_capacity(),
702 young->used_in_bytes(),
703 young->capacity_in_bytes()),
704 HEAP_CHANGE_FORMAT_ARGS("Eden",
705 pre_gc_values.eden_used(),
706 pre_gc_values.eden_capacity(),
707 eden->used_in_bytes(),
708 eden->capacity_in_bytes()),
709 HEAP_CHANGE_FORMAT_ARGS("From",
710 pre_gc_values.from_used(),
711 pre_gc_values.from_capacity(),
712 from->used_in_bytes(),
713 from->capacity_in_bytes()));
714 log_info(gc, heap)(HEAP_CHANGE_FORMAT,
715 HEAP_CHANGE_FORMAT_ARGS(old->name(),
716 pre_gc_values.old_gen_used(),
717 pre_gc_values.old_gen_capacity(),
718 old->used_in_bytes(),
719 old->capacity_in_bytes()));
720 MetaspaceUtils::print_metaspace_change(pre_gc_values.metaspace_sizes());
721 }
722
723 void ParallelScavengeHeap::verify(VerifyOption option /* ignored */) {
724 // Why do we need the total_collections()-filter below?
725 if (total_collections() > 0) {
726 log_debug(gc, verify)("Tenured");
727 old_gen()->verify();
728
729 log_debug(gc, verify)("Eden");
730 young_gen()->verify();
731
732 log_debug(gc, verify)("CardTable");
733 card_table()->verify_all_young_refs_imprecise();
734 }
735 }
736
737 void ParallelScavengeHeap::trace_actual_reserved_page_size(const size_t reserved_heap_size, const ReservedSpace rs) {
738 // Check if Info level is enabled, since os::trace_page_sizes() logs on Info level.
739 if(log_is_enabled(Info, pagesize)) {
740 const size_t page_size = rs.page_size();
741 os::trace_page_sizes("Heap",
742 MinHeapSize,
743 reserved_heap_size,
744 rs.base(),
745 rs.size(),
746 page_size);
747 }
748 }
749
750 void ParallelScavengeHeap::trace_heap(GCWhen::Type when, const GCTracer* gc_tracer) {
751 const PSHeapSummary& heap_summary = create_ps_heap_summary();
752 gc_tracer->report_gc_heap_summary(when, heap_summary);
753
754 const MetaspaceSummary& metaspace_summary = create_metaspace_summary();
755 gc_tracer->report_metaspace_summary(when, metaspace_summary);
756 }
757
758 CardTableBarrierSet* ParallelScavengeHeap::barrier_set() {
759 return barrier_set_cast<CardTableBarrierSet>(BarrierSet::barrier_set());
760 }
761
762 PSCardTable* ParallelScavengeHeap::card_table() {
763 return static_cast<PSCardTable*>(barrier_set()->card_table());
764 }
765
766 void ParallelScavengeHeap::resize_young_gen(size_t eden_size,
767 size_t survivor_size) {
768 // Delegate the resize to the generation.
769 _young_gen->resize(eden_size, survivor_size);
770 }
771
772 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) {
773 // Delegate the resize to the generation.
774 _old_gen->resize(desired_free_space);
775 }
776
777 HeapWord* ParallelScavengeHeap::allocate_loaded_archive_space(size_t size) {
778 return _old_gen->allocate(size);
779 }
780
781 void ParallelScavengeHeap::complete_loaded_archive_space(MemRegion archive_space) {
782 assert(_old_gen->object_space()->used_region().contains(archive_space),
783 "Archive space not contained in old gen");
784 _old_gen->complete_loaded_archive_space(archive_space);
785 }
786
787 void ParallelScavengeHeap::register_nmethod(nmethod* nm) {
788 ScavengableNMethods::register_nmethod(nm);
789 }
790
791 void ParallelScavengeHeap::unregister_nmethod(nmethod* nm) {
792 ScavengableNMethods::unregister_nmethod(nm);
793 }
794
795 void ParallelScavengeHeap::verify_nmethod(nmethod* nm) {
796 ScavengableNMethods::verify_nmethod(nm);
797 }
798
799 GrowableArray<GCMemoryManager*> ParallelScavengeHeap::memory_managers() {
800 GrowableArray<GCMemoryManager*> memory_managers(2);
801 memory_managers.append(_young_manager);
802 memory_managers.append(_old_manager);
803 return memory_managers;
804 }
805
806 GrowableArray<MemoryPool*> ParallelScavengeHeap::memory_pools() {
807 GrowableArray<MemoryPool*> memory_pools(3);
808 memory_pools.append(_eden_pool);
809 memory_pools.append(_survivor_pool);
810 memory_pools.append(_old_pool);
811 return memory_pools;
812 }
813
814 void ParallelScavengeHeap::pin_object(JavaThread* thread, oop obj) {
815 GCLocker::enter(thread);
816 }
817
818 void ParallelScavengeHeap::unpin_object(JavaThread* thread, oop obj) {
819 GCLocker::exit(thread);
820 }
821
822 void ParallelScavengeHeap::update_parallel_worker_threads_cpu_time() {
823 assert(Thread::current()->is_VM_thread(),
824 "Must be called from VM thread to avoid races");
825 if (!UsePerfData || !os::is_thread_cpu_time_supported()) {
826 return;
827 }
828
829 // Ensure ThreadTotalCPUTimeClosure destructor is called before publishing gc
830 // time.
831 {
832 ThreadTotalCPUTimeClosure tttc(CPUTimeGroups::CPUTimeType::gc_parallel_workers);
833 // Currently parallel worker threads in GCTaskManager never terminate, so it
834 // is safe for VMThread to read their CPU times. If upstream changes this
835 // behavior, we should rethink if it is still safe.
836 gc_threads_do(&tttc);
837 }
838
839 CPUTimeCounters::publish_gc_total_cpu_time();
840 }