1 /*
2 * Copyright (c) 2001, 2013, 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 "precompiled.hpp"
26 #include "gc_implementation/parallelScavenge/adjoiningGenerations.hpp"
27 #include "gc_implementation/parallelScavenge/adjoiningVirtualSpaces.hpp"
28 #include "gc_implementation/parallelScavenge/cardTableExtension.hpp"
29 #include "gc_implementation/parallelScavenge/gcTaskManager.hpp"
30 #include "gc_implementation/parallelScavenge/generationSizer.hpp"
31 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
32 #include "gc_implementation/parallelScavenge/psAdaptiveSizePolicy.hpp"
33 #include "gc_implementation/parallelScavenge/psMarkSweep.hpp"
34 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp"
35 #include "gc_implementation/parallelScavenge/psPromotionManager.hpp"
36 #include "gc_implementation/parallelScavenge/psScavenge.hpp"
37 #include "gc_implementation/parallelScavenge/vmPSOperations.hpp"
38 #include "gc_implementation/shared/gcHeapSummary.hpp"
39 #include "gc_implementation/shared/gcWhen.hpp"
40 #include "memory/gcLocker.inline.hpp"
41 #include "oops/oop.inline.hpp"
42 #include "runtime/handles.inline.hpp"
43 #include "runtime/java.hpp"
44 #include "runtime/vmThread.hpp"
45 #include "services/memTracker.hpp"
46 #include "utilities/vmError.hpp"
47
48 PSYoungGen* ParallelScavengeHeap::_young_gen = NULL;
49 PSOldGen* ParallelScavengeHeap::_old_gen = NULL;
50 PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = NULL;
51 PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = NULL;
52 ParallelScavengeHeap* ParallelScavengeHeap::_psh = NULL;
53 GCTaskManager* ParallelScavengeHeap::_gc_task_manager = NULL;
54
55 static void trace_gen_sizes(const char* const str,
56 size_t og_min, size_t og_max,
57 size_t yg_min, size_t yg_max)
58 {
59 if (TracePageSizes) {
60 tty->print_cr("%s: " SIZE_FORMAT "," SIZE_FORMAT " "
61 SIZE_FORMAT "," SIZE_FORMAT " "
62 SIZE_FORMAT,
63 str,
64 og_min / K, og_max / K,
65 yg_min / K, yg_max / K,
66 (og_max + yg_max) / K);
67 }
68 }
69
70 jint ParallelScavengeHeap::initialize() {
71 CollectedHeap::pre_initialize();
72
73 // Cannot be initialized until after the flags are parsed
74 // GenerationSizer flag_parser;
75 _collector_policy = new GenerationSizer();
76
77 size_t yg_min_size = _collector_policy->min_young_gen_size();
78 size_t yg_max_size = _collector_policy->max_young_gen_size();
79 size_t og_min_size = _collector_policy->min_old_gen_size();
80 size_t og_max_size = _collector_policy->max_old_gen_size();
81
82 trace_gen_sizes("ps heap raw",
83 og_min_size, og_max_size,
84 yg_min_size, yg_max_size);
85
86 const size_t og_page_sz = os::page_size_for_region(yg_min_size + og_min_size,
87 yg_max_size + og_max_size,
88 8);
89
90 const size_t og_align = set_alignment(_old_gen_alignment, og_page_sz);
91 const size_t yg_align = set_alignment(_young_gen_alignment, og_page_sz);
92
93 // Update sizes to reflect the selected page size(s).
94 //
95 // NEEDS_CLEANUP. The default TwoGenerationCollectorPolicy uses NewRatio; it
96 // should check UseAdaptiveSizePolicy. Changes from generationSizer could
97 // move to the common code.
98 yg_min_size = align_size_up(yg_min_size, yg_align);
99 yg_max_size = align_size_up(yg_max_size, yg_align);
100 size_t yg_cur_size =
101 align_size_up(_collector_policy->young_gen_size(), yg_align);
102 yg_cur_size = MAX2(yg_cur_size, yg_min_size);
103
104 og_min_size = align_size_up(og_min_size, og_align);
105 // Align old gen size down to preserve specified heap size.
106 assert(og_align == yg_align, "sanity");
107 og_max_size = align_size_down(og_max_size, og_align);
108 og_max_size = MAX2(og_max_size, og_min_size);
109 size_t og_cur_size =
110 align_size_down(_collector_policy->old_gen_size(), og_align);
111 og_cur_size = MAX2(og_cur_size, og_min_size);
112
113 trace_gen_sizes("ps heap rnd",
114 og_min_size, og_max_size,
115 yg_min_size, yg_max_size);
116
117 const size_t heap_size = og_max_size + yg_max_size;
118
119 ReservedSpace heap_rs = Universe::reserve_heap(heap_size, og_align);
120
121 MemTracker::record_virtual_memory_type((address)heap_rs.base(), mtJavaHeap);
122
123 os::trace_page_sizes("ps main", og_min_size + yg_min_size,
124 og_max_size + yg_max_size, og_page_sz,
125 heap_rs.base(),
126 heap_rs.size());
127 if (!heap_rs.is_reserved()) {
128 vm_shutdown_during_initialization(
129 "Could not reserve enough space for object heap");
130 return JNI_ENOMEM;
131 }
132
133 _reserved = MemRegion((HeapWord*)heap_rs.base(),
134 (HeapWord*)(heap_rs.base() + heap_rs.size()));
135
136 CardTableExtension* const barrier_set = new CardTableExtension(_reserved, 3);
137 _barrier_set = barrier_set;
138 oopDesc::set_bs(_barrier_set);
139 if (_barrier_set == NULL) {
140 vm_shutdown_during_initialization(
141 "Could not reserve enough space for barrier set");
142 return JNI_ENOMEM;
143 }
144
145 // Initial young gen size is 4 Mb
146 //
147 // XXX - what about flag_parser.young_gen_size()?
148 const size_t init_young_size = align_size_up(4 * M, yg_align);
149 yg_cur_size = MAX2(MIN2(init_young_size, yg_max_size), yg_cur_size);
150
151 // Make up the generations
152 // Calculate the maximum size that a generation can grow. This
153 // includes growth into the other generation. Note that the
154 // parameter _max_gen_size is kept as the maximum
155 // size of the generation as the boundaries currently stand.
156 // _max_gen_size is still used as that value.
157 double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0;
158 double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0;
159
160 _gens = new AdjoiningGenerations(heap_rs,
161 og_cur_size,
162 og_min_size,
163 og_max_size,
164 yg_cur_size,
165 yg_min_size,
166 yg_max_size,
167 yg_align);
168
169 _old_gen = _gens->old_gen();
170 _young_gen = _gens->young_gen();
171
172 const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes();
173 const size_t old_capacity = _old_gen->capacity_in_bytes();
174 const size_t initial_promo_size = MIN2(eden_capacity, old_capacity);
175 _size_policy =
176 new PSAdaptiveSizePolicy(eden_capacity,
177 initial_promo_size,
178 young_gen()->to_space()->capacity_in_bytes(),
179 intra_heap_alignment(),
180 max_gc_pause_sec,
181 max_gc_minor_pause_sec,
182 GCTimeRatio
183 );
184
185 assert(!UseAdaptiveGCBoundary ||
186 (old_gen()->virtual_space()->high_boundary() ==
187 young_gen()->virtual_space()->low_boundary()),
188 "Boundaries must meet");
189 // initialize the policy counters - 2 collectors, 3 generations
190 _gc_policy_counters =
191 new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 3, _size_policy);
192 _psh = this;
193
194 // Set up the GCTaskManager
195 _gc_task_manager = GCTaskManager::create(ParallelGCThreads);
196
197 if (UseParallelOldGC && !PSParallelCompact::initialize()) {
198 return JNI_ENOMEM;
199 }
200
201 return JNI_OK;
202 }
203
204 void ParallelScavengeHeap::post_initialize() {
205 // Need to init the tenuring threshold
206 PSScavenge::initialize();
207 if (UseParallelOldGC) {
208 PSParallelCompact::post_initialize();
209 } else {
210 PSMarkSweep::initialize();
211 }
212 PSPromotionManager::initialize();
213 }
214
215 void ParallelScavengeHeap::update_counters() {
216 young_gen()->update_counters();
217 old_gen()->update_counters();
218 MetaspaceCounters::update_performance_counters();
219 CompressedClassSpaceCounters::update_performance_counters();
220 }
221
222 size_t ParallelScavengeHeap::capacity() const {
223 size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes();
224 return value;
225 }
226
227 size_t ParallelScavengeHeap::used() const {
228 size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes();
229 return value;
230 }
231
232 bool ParallelScavengeHeap::is_maximal_no_gc() const {
233 return old_gen()->is_maximal_no_gc() && young_gen()->is_maximal_no_gc();
234 }
235
236
237 size_t ParallelScavengeHeap::max_capacity() const {
238 size_t estimated = reserved_region().byte_size();
239 if (UseAdaptiveSizePolicy) {
240 estimated -= _size_policy->max_survivor_size(young_gen()->max_size());
241 } else {
242 estimated -= young_gen()->to_space()->capacity_in_bytes();
243 }
244 return MAX2(estimated, capacity());
245 }
246
247 bool ParallelScavengeHeap::is_in(const void* p) const {
248 if (young_gen()->is_in(p)) {
249 return true;
250 }
251
252 if (old_gen()->is_in(p)) {
253 return true;
254 }
255
256 return false;
257 }
258
259 bool ParallelScavengeHeap::is_in_reserved(const void* p) const {
260 if (young_gen()->is_in_reserved(p)) {
261 return true;
262 }
263
264 if (old_gen()->is_in_reserved(p)) {
265 return true;
266 }
267
268 return false;
269 }
270
271 bool ParallelScavengeHeap::is_scavengable(const void* addr) {
272 return is_in_young((oop)addr);
273 }
274
275 #ifdef ASSERT
276 // Don't implement this by using is_in_young(). This method is used
277 // in some cases to check that is_in_young() is correct.
278 bool ParallelScavengeHeap::is_in_partial_collection(const void *p) {
279 assert(is_in_reserved(p) || p == NULL,
280 "Does not work if address is non-null and outside of the heap");
281 // The order of the generations is old (low addr), young (high addr)
282 return p >= old_gen()->reserved().end();
283 }
284 #endif
285
286 // There are two levels of allocation policy here.
287 //
288 // When an allocation request fails, the requesting thread must invoke a VM
289 // operation, transfer control to the VM thread, and await the results of a
290 // garbage collection. That is quite expensive, and we should avoid doing it
291 // multiple times if possible.
292 //
293 // To accomplish this, we have a basic allocation policy, and also a
294 // failed allocation policy.
295 //
296 // The basic allocation policy controls how you allocate memory without
297 // attempting garbage collection. It is okay to grab locks and
298 // expand the heap, if that can be done without coming to a safepoint.
299 // It is likely that the basic allocation policy will not be very
300 // aggressive.
301 //
302 // The failed allocation policy is invoked from the VM thread after
303 // the basic allocation policy is unable to satisfy a mem_allocate
304 // request. This policy needs to cover the entire range of collection,
305 // heap expansion, and out-of-memory conditions. It should make every
306 // attempt to allocate the requested memory.
307
308 // Basic allocation policy. Should never be called at a safepoint, or
309 // from the VM thread.
310 //
311 // This method must handle cases where many mem_allocate requests fail
312 // simultaneously. When that happens, only one VM operation will succeed,
313 // and the rest will not be executed. For that reason, this method loops
314 // during failed allocation attempts. If the java heap becomes exhausted,
315 // we rely on the size_policy object to force a bail out.
316 HeapWord* ParallelScavengeHeap::mem_allocate(
317 size_t size,
318 bool* gc_overhead_limit_was_exceeded) {
319 assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint");
320 assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread");
321 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
322
323 // In general gc_overhead_limit_was_exceeded should be false so
324 // set it so here and reset it to true only if the gc time
325 // limit is being exceeded as checked below.
326 *gc_overhead_limit_was_exceeded = false;
327
328 HeapWord* result = young_gen()->allocate(size);
329
330 uint loop_count = 0;
331 uint gc_count = 0;
332 int gclocker_stalled_count = 0;
333
334 while (result == NULL) {
335 // We don't want to have multiple collections for a single filled generation.
336 // To prevent this, each thread tracks the total_collections() value, and if
337 // the count has changed, does not do a new collection.
338 //
339 // The collection count must be read only while holding the heap lock. VM
340 // operations also hold the heap lock during collections. There is a lock
341 // contention case where thread A blocks waiting on the Heap_lock, while
342 // thread B is holding it doing a collection. When thread A gets the lock,
343 // the collection count has already changed. To prevent duplicate collections,
344 // The policy MUST attempt allocations during the same period it reads the
345 // total_collections() value!
346 {
347 MutexLocker ml(Heap_lock);
348 gc_count = Universe::heap()->total_collections();
349
350 result = young_gen()->allocate(size);
351 if (result != NULL) {
352 return result;
353 }
354
355 // If certain conditions hold, try allocating from the old gen.
356 result = mem_allocate_old_gen(size);
357 if (result != NULL) {
358 return result;
359 }
360
361 if (gclocker_stalled_count > GCLockerRetryAllocationCount) {
362 return NULL;
363 }
364
365 // Failed to allocate without a gc.
366 if (GC_locker::is_active_and_needs_gc()) {
367 // If this thread is not in a jni critical section, we stall
368 // the requestor until the critical section has cleared and
369 // GC allowed. When the critical section clears, a GC is
370 // initiated by the last thread exiting the critical section; so
371 // we retry the allocation sequence from the beginning of the loop,
372 // rather than causing more, now probably unnecessary, GC attempts.
373 JavaThread* jthr = JavaThread::current();
374 if (!jthr->in_critical()) {
375 MutexUnlocker mul(Heap_lock);
376 GC_locker::stall_until_clear();
377 gclocker_stalled_count += 1;
378 continue;
379 } else {
380 if (CheckJNICalls) {
381 fatal("Possible deadlock due to allocating while"
382 " in jni critical section");
383 }
384 return NULL;
385 }
386 }
387 }
388
389 if (result == NULL) {
390 // Generate a VM operation
391 VM_ParallelGCFailedAllocation op(size, gc_count);
392 VMThread::execute(&op);
393
394 // Did the VM operation execute? If so, return the result directly.
395 // This prevents us from looping until time out on requests that can
396 // not be satisfied.
397 if (op.prologue_succeeded()) {
398 assert(Universe::heap()->is_in_or_null(op.result()),
399 "result not in heap");
400
401 // If GC was locked out during VM operation then retry allocation
402 // and/or stall as necessary.
403 if (op.gc_locked()) {
404 assert(op.result() == NULL, "must be NULL if gc_locked() is true");
405 continue; // retry and/or stall as necessary
406 }
407
408 // Exit the loop if the gc time limit has been exceeded.
409 // The allocation must have failed above ("result" guarding
410 // this path is NULL) and the most recent collection has exceeded the
411 // gc overhead limit (although enough may have been collected to
412 // satisfy the allocation). Exit the loop so that an out-of-memory
413 // will be thrown (return a NULL ignoring the contents of
414 // op.result()),
415 // but clear gc_overhead_limit_exceeded so that the next collection
416 // starts with a clean slate (i.e., forgets about previous overhead
417 // excesses). Fill op.result() with a filler object so that the
418 // heap remains parsable.
419 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded();
420 const bool softrefs_clear = collector_policy()->all_soft_refs_clear();
421
422 if (limit_exceeded && softrefs_clear) {
423 *gc_overhead_limit_was_exceeded = true;
424 size_policy()->set_gc_overhead_limit_exceeded(false);
425 if (PrintGCDetails && Verbose) {
426 gclog_or_tty->print_cr("ParallelScavengeHeap::mem_allocate: "
427 "return NULL because gc_overhead_limit_exceeded is set");
428 }
429 if (op.result() != NULL) {
430 CollectedHeap::fill_with_object(op.result(), size);
431 }
432 return NULL;
433 }
434
435 return op.result();
436 }
437 }
438
439 // The policy object will prevent us from looping forever. If the
440 // time spent in gc crosses a threshold, we will bail out.
441 loop_count++;
442 if ((result == NULL) && (QueuedAllocationWarningCount > 0) &&
443 (loop_count % QueuedAllocationWarningCount == 0)) {
444 warning("ParallelScavengeHeap::mem_allocate retries %d times \n\t"
445 " size=%d", loop_count, size);
446 }
447 }
448
449 return result;
450 }
451
452 // A "death march" is a series of ultra-slow allocations in which a full gc is
453 // done before each allocation, and after the full gc the allocation still
454 // cannot be satisfied from the young gen. This routine detects that condition;
455 // it should be called after a full gc has been done and the allocation
456 // attempted from the young gen. The parameter 'addr' should be the result of
457 // that young gen allocation attempt.
458 void
459 ParallelScavengeHeap::death_march_check(HeapWord* const addr, size_t size) {
460 if (addr != NULL) {
461 _death_march_count = 0; // death march has ended
462 } else if (_death_march_count == 0) {
463 if (should_alloc_in_eden(size)) {
464 _death_march_count = 1; // death march has started
465 }
466 }
467 }
468
469 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) {
470 if (!should_alloc_in_eden(size) || GC_locker::is_active_and_needs_gc()) {
471 // Size is too big for eden, or gc is locked out.
472 return old_gen()->allocate(size);
473 }
474
475 // If a "death march" is in progress, allocate from the old gen a limited
476 // number of times before doing a GC.
477 if (_death_march_count > 0) {
478 if (_death_march_count < 64) {
479 ++_death_march_count;
480 return old_gen()->allocate(size);
481 } else {
482 _death_march_count = 0;
483 }
484 }
485 return NULL;
486 }
487
488 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) {
489 if (UseParallelOldGC) {
490 // The do_full_collection() parameter clear_all_soft_refs
491 // is interpreted here as maximum_compaction which will
492 // cause SoftRefs to be cleared.
493 bool maximum_compaction = clear_all_soft_refs;
494 PSParallelCompact::invoke(maximum_compaction);
495 } else {
496 PSMarkSweep::invoke(clear_all_soft_refs);
497 }
498 }
499
500 // Failed allocation policy. Must be called from the VM thread, and
501 // only at a safepoint! Note that this method has policy for allocation
502 // flow, and NOT collection policy. So we do not check for gc collection
503 // time over limit here, that is the responsibility of the heap specific
504 // collection methods. This method decides where to attempt allocations,
505 // and when to attempt collections, but no collection specific policy.
506 HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size) {
507 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
508 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
509 assert(!Universe::heap()->is_gc_active(), "not reentrant");
510 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
511
512 // We assume that allocation in eden will fail unless we collect.
513
514 // First level allocation failure, scavenge and allocate in young gen.
515 GCCauseSetter gccs(this, GCCause::_allocation_failure);
516 const bool invoked_full_gc = PSScavenge::invoke();
517 HeapWord* result = young_gen()->allocate(size);
518
519 // Second level allocation failure.
520 // Mark sweep and allocate in young generation.
521 if (result == NULL && !invoked_full_gc) {
522 do_full_collection(false);
523 result = young_gen()->allocate(size);
524 }
525
526 death_march_check(result, size);
527
528 // Third level allocation failure.
529 // After mark sweep and young generation allocation failure,
530 // allocate in old generation.
531 if (result == NULL) {
532 result = old_gen()->allocate(size);
533 }
534
535 // Fourth level allocation failure. We're running out of memory.
536 // More complete mark sweep and allocate in young generation.
537 if (result == NULL) {
538 do_full_collection(true);
539 result = young_gen()->allocate(size);
540 }
541
542 // Fifth level allocation failure.
543 // After more complete mark sweep, allocate in old generation.
544 if (result == NULL) {
545 result = old_gen()->allocate(size);
546 }
547
548 return result;
549 }
550
551 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) {
552 CollectedHeap::ensure_parsability(retire_tlabs);
553 young_gen()->eden_space()->ensure_parsability();
554 }
555
556 size_t ParallelScavengeHeap::unsafe_max_alloc() {
557 return young_gen()->eden_space()->free_in_bytes();
558 }
559
560 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const {
561 return young_gen()->eden_space()->tlab_capacity(thr);
562 }
563
564 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const {
565 return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr);
566 }
567
568 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t size) {
569 return young_gen()->allocate(size);
570 }
571
572 void ParallelScavengeHeap::accumulate_statistics_all_tlabs() {
573 CollectedHeap::accumulate_statistics_all_tlabs();
574 }
575
576 void ParallelScavengeHeap::resize_all_tlabs() {
577 CollectedHeap::resize_all_tlabs();
578 }
579
580 bool ParallelScavengeHeap::can_elide_initializing_store_barrier(oop new_obj) {
581 // We don't need barriers for stores to objects in the
582 // young gen and, a fortiori, for initializing stores to
583 // objects therein.
584 return is_in_young(new_obj);
585 }
586
587 // This method is used by System.gc() and JVMTI.
588 void ParallelScavengeHeap::collect(GCCause::Cause cause) {
589 assert(!Heap_lock->owned_by_self(),
590 "this thread should not own the Heap_lock");
591
592 unsigned int gc_count = 0;
593 unsigned int full_gc_count = 0;
594 {
595 MutexLocker ml(Heap_lock);
596 // This value is guarded by the Heap_lock
597 gc_count = Universe::heap()->total_collections();
598 full_gc_count = Universe::heap()->total_full_collections();
599 }
600
601 VM_ParallelGCSystemGC op(gc_count, full_gc_count, cause);
602 VMThread::execute(&op);
603 }
604
605 void ParallelScavengeHeap::oop_iterate(ExtendedOopClosure* cl) {
606 Unimplemented();
607 }
608
609 void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) {
610 young_gen()->object_iterate(cl);
611 old_gen()->object_iterate(cl);
612 }
613
614
615 HeapWord* ParallelScavengeHeap::block_start(const void* addr) const {
616 if (young_gen()->is_in_reserved(addr)) {
617 assert(young_gen()->is_in(addr),
618 "addr should be in allocated part of young gen");
619 // called from os::print_location by find or VMError
620 if (Debugging || VMError::fatal_error_in_progress()) return NULL;
621 Unimplemented();
622 } else if (old_gen()->is_in_reserved(addr)) {
623 assert(old_gen()->is_in(addr),
624 "addr should be in allocated part of old gen");
625 return old_gen()->start_array()->object_start((HeapWord*)addr);
626 }
627 return 0;
628 }
629
630 size_t ParallelScavengeHeap::block_size(const HeapWord* addr) const {
631 return oop(addr)->size();
632 }
633
634 bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const {
635 return block_start(addr) == addr;
636 }
637
638 jlong ParallelScavengeHeap::millis_since_last_gc() {
639 return UseParallelOldGC ?
640 PSParallelCompact::millis_since_last_gc() :
641 PSMarkSweep::millis_since_last_gc();
642 }
643
644 void ParallelScavengeHeap::prepare_for_verify() {
645 ensure_parsability(false); // no need to retire TLABs for verification
646 }
647
648 PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() {
649 PSOldGen* old = old_gen();
650 HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr();
651 VirtualSpaceSummary old_summary(old->reserved().start(), old_committed_end, old->reserved().end());
652 SpaceSummary old_space(old->reserved().start(), old_committed_end, old->used_in_bytes());
653
654 PSYoungGen* young = young_gen();
655 VirtualSpaceSummary young_summary(young->reserved().start(),
656 (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end());
657
658 MutableSpace* eden = young_gen()->eden_space();
659 SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes());
660
661 MutableSpace* from = young_gen()->from_space();
662 SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes());
663
664 MutableSpace* to = young_gen()->to_space();
665 SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes());
666
667 VirtualSpaceSummary heap_summary = create_heap_space_summary();
668 return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space);
669 }
670
671 void ParallelScavengeHeap::print_on(outputStream* st) const {
672 young_gen()->print_on(st);
673 old_gen()->print_on(st);
674 MetaspaceAux::print_on(st);
675 }
676
677 void ParallelScavengeHeap::print_on_error(outputStream* st) const {
678 this->CollectedHeap::print_on_error(st);
679
680 if (UseParallelOldGC) {
681 st->cr();
682 PSParallelCompact::print_on_error(st);
683 }
684 }
685
686 void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const {
687 PSScavenge::gc_task_manager()->threads_do(tc);
688 }
689
690 void ParallelScavengeHeap::print_gc_threads_on(outputStream* st) const {
691 PSScavenge::gc_task_manager()->print_threads_on(st);
692 }
693
694 void ParallelScavengeHeap::print_tracing_info() const {
695 if (TraceGen0Time) {
696 double time = PSScavenge::accumulated_time()->seconds();
697 tty->print_cr("[Accumulated GC generation 0 time %3.7f secs]", time);
698 }
699 if (TraceGen1Time) {
700 double time = UseParallelOldGC ? PSParallelCompact::accumulated_time()->seconds() : PSMarkSweep::accumulated_time()->seconds();
701 tty->print_cr("[Accumulated GC generation 1 time %3.7f secs]", time);
702 }
703 }
704
705
706 void ParallelScavengeHeap::verify(bool silent, VerifyOption option /* ignored */) {
707 // Why do we need the total_collections()-filter below?
708 if (total_collections() > 0) {
709 if (!silent) {
710 gclog_or_tty->print("tenured ");
711 }
712 old_gen()->verify();
713
714 if (!silent) {
715 gclog_or_tty->print("eden ");
716 }
717 young_gen()->verify();
718 }
719 }
720
721 void ParallelScavengeHeap::print_heap_change(size_t prev_used) {
722 if (PrintGCDetails && Verbose) {
723 gclog_or_tty->print(" " SIZE_FORMAT
724 "->" SIZE_FORMAT
725 "(" SIZE_FORMAT ")",
726 prev_used, used(), capacity());
727 } else {
728 gclog_or_tty->print(" " SIZE_FORMAT "K"
729 "->" SIZE_FORMAT "K"
730 "(" SIZE_FORMAT "K)",
731 prev_used / K, used() / K, capacity() / K);
732 }
733 }
734
735 void ParallelScavengeHeap::trace_heap(GCWhen::Type when, GCTracer* gc_tracer) {
736 const PSHeapSummary& heap_summary = create_ps_heap_summary();
737 const MetaspaceSummary& metaspace_summary = create_metaspace_summary();
738 gc_tracer->report_gc_heap_summary(when, heap_summary, metaspace_summary);
739 }
740
741 ParallelScavengeHeap* ParallelScavengeHeap::heap() {
742 assert(_psh != NULL, "Uninitialized access to ParallelScavengeHeap::heap()");
743 assert(_psh->kind() == CollectedHeap::ParallelScavengeHeap, "not a parallel scavenge heap");
744 return _psh;
745 }
746
747 // Before delegating the resize to the young generation,
748 // the reserved space for the young and old generations
749 // may be changed to accomodate the desired resize.
750 void ParallelScavengeHeap::resize_young_gen(size_t eden_size,
751 size_t survivor_size) {
752 if (UseAdaptiveGCBoundary) {
753 if (size_policy()->bytes_absorbed_from_eden() != 0) {
754 size_policy()->reset_bytes_absorbed_from_eden();
755 return; // The generation changed size already.
756 }
757 gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size);
758 }
759
760 // Delegate the resize to the generation.
761 _young_gen->resize(eden_size, survivor_size);
762 }
763
764 // Before delegating the resize to the old generation,
765 // the reserved space for the young and old generations
766 // may be changed to accomodate the desired resize.
767 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) {
768 if (UseAdaptiveGCBoundary) {
769 if (size_policy()->bytes_absorbed_from_eden() != 0) {
770 size_policy()->reset_bytes_absorbed_from_eden();
771 return; // The generation changed size already.
772 }
773 gens()->adjust_boundary_for_old_gen_needs(desired_free_space);
774 }
775
776 // Delegate the resize to the generation.
777 _old_gen->resize(desired_free_space);
778 }
779
780 ParallelScavengeHeap::ParStrongRootsScope::ParStrongRootsScope() {
781 // nothing particular
782 }
783
784 ParallelScavengeHeap::ParStrongRootsScope::~ParStrongRootsScope() {
785 // nothing particular
786 }
787
788 #ifndef PRODUCT
789 void ParallelScavengeHeap::record_gen_tops_before_GC() {
790 if (ZapUnusedHeapArea) {
791 young_gen()->record_spaces_top();
792 old_gen()->record_spaces_top();
793 }
794 }
795
796 void ParallelScavengeHeap::gen_mangle_unused_area() {
797 if (ZapUnusedHeapArea) {
798 young_gen()->eden_space()->mangle_unused_area();
799 young_gen()->to_space()->mangle_unused_area();
800 young_gen()->from_space()->mangle_unused_area();
801 old_gen()->object_space()->mangle_unused_area();
802 }
803 }
804 #endif