1 /*
2 * Copyright (c) 2014, 2021, 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/g1/g1Allocator.inline.hpp"
27 #include "gc/g1/g1CollectedHeap.inline.hpp"
28 #include "gc/g1/g1CollectionSet.hpp"
29 #include "gc/g1/g1OopClosures.inline.hpp"
30 #include "gc/g1/g1ParScanThreadState.inline.hpp"
31 #include "gc/g1/g1RootClosures.hpp"
32 #include "gc/g1/g1StringDedup.hpp"
33 #include "gc/g1/g1Trace.hpp"
34 #include "gc/shared/partialArrayTaskStepper.inline.hpp"
35 #include "gc/shared/stringdedup/stringDedup.hpp"
36 #include "gc/shared/taskqueue.inline.hpp"
37 #include "memory/allocation.inline.hpp"
38 #include "oops/access.inline.hpp"
39 #include "oops/oop.inline.hpp"
40 #include "runtime/atomic.hpp"
41 #include "runtime/prefetch.inline.hpp"
42 #include "utilities/globalDefinitions.hpp"
43 #include "utilities/macros.hpp"
44
45 // In fastdebug builds the code size can get out of hand, potentially
46 // tripping over compiler limits (which may be bugs, but nevertheless
47 // need to be taken into consideration). A side benefit of limiting
48 // inlining is that we get more call frames that might aid debugging.
49 // And the fastdebug compile time for this file is much reduced.
50 // Explicit NOINLINE to block ATTRIBUTE_FLATTENing.
51 #define MAYBE_INLINE_EVACUATION NOT_DEBUG(inline) DEBUG_ONLY(NOINLINE)
52
53 G1ParScanThreadState::G1ParScanThreadState(G1CollectedHeap* g1h,
54 G1RedirtyCardsQueueSet* rdcqs,
55 uint worker_id,
56 uint n_workers,
57 size_t young_cset_length,
58 size_t optional_cset_length)
59 : _g1h(g1h),
60 _task_queue(g1h->task_queue(worker_id)),
61 _rdc_local_qset(rdcqs),
62 _ct(g1h->card_table()),
63 _closures(NULL),
64 _plab_allocator(NULL),
65 _age_table(false),
66 _tenuring_threshold(g1h->policy()->tenuring_threshold()),
67 _scanner(g1h, this),
68 _worker_id(worker_id),
69 _last_enqueued_card(SIZE_MAX),
70 _stack_trim_upper_threshold(GCDrainStackTargetSize * 2 + 1),
71 _stack_trim_lower_threshold(GCDrainStackTargetSize),
72 _trim_ticks(),
73 _surviving_young_words_base(NULL),
74 _surviving_young_words(NULL),
75 _surviving_words_length(young_cset_length + 1),
76 _old_gen_is_full(false),
77 _partial_objarray_chunk_size(ParGCArrayScanChunk),
78 _partial_array_stepper(n_workers),
79 _string_dedup_requests(),
80 _num_optional_regions(optional_cset_length),
81 _numa(g1h->numa()),
82 _obj_alloc_stat(NULL)
83 {
84 // We allocate number of young gen regions in the collection set plus one
85 // entries, since entry 0 keeps track of surviving bytes for non-young regions.
86 // We also add a few elements at the beginning and at the end in
87 // an attempt to eliminate cache contention
88 const size_t padding_elem_num = (DEFAULT_CACHE_LINE_SIZE / sizeof(size_t));
89 size_t array_length = padding_elem_num + _surviving_words_length + padding_elem_num;
90
91 _surviving_young_words_base = NEW_C_HEAP_ARRAY(size_t, array_length, mtGC);
92 _surviving_young_words = _surviving_young_words_base + padding_elem_num;
93 memset(_surviving_young_words, 0, _surviving_words_length * sizeof(size_t));
94
95 _plab_allocator = new G1PLABAllocator(_g1h->allocator());
96
97 // The dest for Young is used when the objects are aged enough to
98 // need to be moved to the next space.
99 _dest[G1HeapRegionAttr::Young] = G1HeapRegionAttr::Old;
100 _dest[G1HeapRegionAttr::Old] = G1HeapRegionAttr::Old;
101
102 _closures = G1EvacuationRootClosures::create_root_closures(this, _g1h);
103
104 _oops_into_optional_regions = new G1OopStarChunkedList[_num_optional_regions];
105
106 initialize_numa_stats();
107 }
108
109 size_t G1ParScanThreadState::flush(size_t* surviving_young_words) {
110 _rdc_local_qset.flush();
111 flush_numa_stats();
112 // Update allocation statistics.
113 _plab_allocator->flush_and_retire_stats();
114 _g1h->policy()->record_age_table(&_age_table);
115
116 size_t sum = 0;
117 for (uint i = 0; i < _surviving_words_length; i++) {
118 surviving_young_words[i] += _surviving_young_words[i];
119 sum += _surviving_young_words[i];
120 }
121 return sum;
122 }
123
124 G1ParScanThreadState::~G1ParScanThreadState() {
125 delete _plab_allocator;
126 delete _closures;
127 FREE_C_HEAP_ARRAY(size_t, _surviving_young_words_base);
128 delete[] _oops_into_optional_regions;
129 FREE_C_HEAP_ARRAY(size_t, _obj_alloc_stat);
130 }
131
132 size_t G1ParScanThreadState::lab_waste_words() const {
133 return _plab_allocator->waste();
134 }
135
136 size_t G1ParScanThreadState::lab_undo_waste_words() const {
137 return _plab_allocator->undo_waste();
138 }
139
140 #ifdef ASSERT
141 void G1ParScanThreadState::verify_task(narrowOop* task) const {
142 assert(task != NULL, "invariant");
143 assert(UseCompressedOops, "sanity");
144 oop p = RawAccess<>::oop_load(task);
145 assert(_g1h->is_in_reserved(p),
146 "task=" PTR_FORMAT " p=" PTR_FORMAT, p2i(task), p2i(p));
147 }
148
149 void G1ParScanThreadState::verify_task(oop* task) const {
150 assert(task != NULL, "invariant");
151 oop p = RawAccess<>::oop_load(task);
152 assert(_g1h->is_in_reserved(p),
153 "task=" PTR_FORMAT " p=" PTR_FORMAT, p2i(task), p2i(p));
154 }
155
156 void G1ParScanThreadState::verify_task(PartialArrayScanTask task) const {
157 // Must be in the collection set--it's already been copied.
158 oop p = task.to_source_array();
159 assert(_g1h->is_in_cset(p), "p=" PTR_FORMAT, p2i(p));
160 }
161
162 void G1ParScanThreadState::verify_task(ScannerTask task) const {
163 if (task.is_narrow_oop_ptr()) {
164 verify_task(task.to_narrow_oop_ptr());
165 } else if (task.is_oop_ptr()) {
166 verify_task(task.to_oop_ptr());
167 } else if (task.is_partial_array_task()) {
168 verify_task(task.to_partial_array_task());
169 } else {
170 ShouldNotReachHere();
171 }
172 }
173 #endif // ASSERT
174
175 template <class T>
176 MAYBE_INLINE_EVACUATION
177 void G1ParScanThreadState::do_oop_evac(T* p) {
178 // Reference should not be NULL here as such are never pushed to the task queue.
179 oop obj = RawAccess<IS_NOT_NULL>::oop_load(p);
180
181 // Although we never intentionally push references outside of the collection
182 // set, due to (benign) races in the claim mechanism during RSet scanning more
183 // than one thread might claim the same card. So the same card may be
184 // processed multiple times, and so we might get references into old gen here.
185 // So we need to redo this check.
186 const G1HeapRegionAttr region_attr = _g1h->region_attr(obj);
187 // References pushed onto the work stack should never point to a humongous region
188 // as they are not added to the collection set due to above precondition.
189 assert(!region_attr.is_humongous(),
190 "Obj " PTR_FORMAT " should not refer to humongous region %u from " PTR_FORMAT,
191 p2i(obj), _g1h->addr_to_region(cast_from_oop<HeapWord*>(obj)), p2i(p));
192
193 if (!region_attr.is_in_cset()) {
194 // In this case somebody else already did all the work.
195 return;
196 }
197
198 markWord m = obj->mark();
199 if (m.is_marked()) {
200 obj = obj->forwardee(m);
201 } else {
202 obj = do_copy_to_survivor_space(region_attr, obj, m);
203 }
204 RawAccess<IS_NOT_NULL>::oop_store(p, obj);
205
206 write_ref_field_post(p, obj);
207 }
208
209 MAYBE_INLINE_EVACUATION
210 void G1ParScanThreadState::do_partial_array(PartialArrayScanTask task) {
211 oop from_obj = task.to_source_array();
212
213 assert(_g1h->is_in_reserved(from_obj), "must be in heap.");
214 assert(UseCompactObjectHeaders || from_obj->is_objArray(), "must be obj array");
215 assert(from_obj->is_forwarded(), "must be forwarded");
216
217 oop to_obj = from_obj->forwardee();
218 assert(from_obj != to_obj, "should not be chunking self-forwarded objects");
219 assert(to_obj->is_objArray(), "must be obj array");
220 objArrayOop to_array = objArrayOop(to_obj);
221
222 PartialArrayTaskStepper::Step step
223 = _partial_array_stepper.next(objArrayOop(from_obj),
224 to_array,
225 _partial_objarray_chunk_size);
226 for (uint i = 0; i < step._ncreate; ++i) {
227 push_on_queue(ScannerTask(PartialArrayScanTask(from_obj)));
228 }
229
230 HeapRegion* hr = _g1h->heap_region_containing(to_array);
231 G1ScanInYoungSetter x(&_scanner, hr->is_young());
232 // Process claimed task. The length of to_array is not correct, but
233 // fortunately the iteration ignores the length field and just relies
234 // on start/end.
235 to_array->oop_iterate_range(&_scanner,
236 step._index,
237 step._index + _partial_objarray_chunk_size);
238 }
239
240 MAYBE_INLINE_EVACUATION
241 void G1ParScanThreadState::start_partial_objarray(G1HeapRegionAttr dest_attr,
242 oop from_obj,
243 oop to_obj) {
244 assert(UseCompactObjectHeaders || from_obj->is_objArray(), "precondition");
245 assert(from_obj->is_forwarded(), "precondition");
246 assert(from_obj->forwardee() == to_obj, "precondition");
247 assert(from_obj != to_obj, "should not be scanning self-forwarded objects");
248 assert(to_obj->is_objArray(), "precondition");
249
250 objArrayOop to_array = objArrayOop(to_obj);
251
252 PartialArrayTaskStepper::Step step
253 = _partial_array_stepper.start(objArrayOop(from_obj),
254 to_array,
255 _partial_objarray_chunk_size);
256
257 // Push any needed partial scan tasks. Pushed before processing the
258 // intitial chunk to allow other workers to steal while we're processing.
259 for (uint i = 0; i < step._ncreate; ++i) {
260 push_on_queue(ScannerTask(PartialArrayScanTask(from_obj)));
261 }
262
263 G1ScanInYoungSetter x(&_scanner, dest_attr.is_young());
264 // Process the initial chunk. No need to process the type in the
265 // klass, as it will already be handled by processing the built-in
266 // module. The length of to_array is not correct, but fortunately
267 // the iteration ignores that length field and relies on start/end.
268 to_array->oop_iterate_range(&_scanner, 0, step._index);
269 }
270
271 MAYBE_INLINE_EVACUATION
272 void G1ParScanThreadState::dispatch_task(ScannerTask task) {
273 verify_task(task);
274 if (task.is_narrow_oop_ptr()) {
275 do_oop_evac(task.to_narrow_oop_ptr());
276 } else if (task.is_oop_ptr()) {
277 do_oop_evac(task.to_oop_ptr());
278 } else {
279 do_partial_array(task.to_partial_array_task());
280 }
281 }
282
283 // Process tasks until overflow queue is empty and local queue
284 // contains no more than threshold entries. NOINLINE to prevent
285 // inlining into steal_and_trim_queue.
286 ATTRIBUTE_FLATTEN NOINLINE
287 void G1ParScanThreadState::trim_queue_to_threshold(uint threshold) {
288 ScannerTask task;
289 do {
290 while (_task_queue->pop_overflow(task)) {
291 if (!_task_queue->try_push_to_taskqueue(task)) {
292 dispatch_task(task);
293 }
294 }
295 while (_task_queue->pop_local(task, threshold)) {
296 dispatch_task(task);
297 }
298 } while (!_task_queue->overflow_empty());
299 }
300
301 ATTRIBUTE_FLATTEN
302 void G1ParScanThreadState::steal_and_trim_queue(G1ScannerTasksQueueSet* task_queues) {
303 ScannerTask stolen_task;
304 while (task_queues->steal(_worker_id, stolen_task)) {
305 dispatch_task(stolen_task);
306 // Processing stolen task may have added tasks to our queue.
307 trim_queue();
308 }
309 }
310
311 HeapWord* G1ParScanThreadState::allocate_in_next_plab(G1HeapRegionAttr* dest,
312 size_t word_sz,
313 bool previous_plab_refill_failed,
314 uint node_index) {
315
316 assert(dest->is_in_cset_or_humongous(), "Unexpected dest: %s region attr", dest->get_type_str());
317
318 // Right now we only have two types of regions (young / old) so
319 // let's keep the logic here simple. We can generalize it when necessary.
320 if (dest->is_young()) {
321 bool plab_refill_in_old_failed = false;
322 HeapWord* const obj_ptr = _plab_allocator->allocate(G1HeapRegionAttr::Old,
323 word_sz,
324 &plab_refill_in_old_failed,
325 node_index);
326 // Make sure that we won't attempt to copy any other objects out
327 // of a survivor region (given that apparently we cannot allocate
328 // any new ones) to avoid coming into this slow path again and again.
329 // Only consider failed PLAB refill here: failed inline allocations are
330 // typically large, so not indicative of remaining space.
331 if (previous_plab_refill_failed) {
332 _tenuring_threshold = 0;
333 }
334
335 if (obj_ptr != NULL) {
336 dest->set_old();
337 } else {
338 // We just failed to allocate in old gen. The same idea as explained above
339 // for making survivor gen unavailable for allocation applies for old gen.
340 _old_gen_is_full = plab_refill_in_old_failed;
341 }
342 return obj_ptr;
343 } else {
344 _old_gen_is_full = previous_plab_refill_failed;
345 assert(dest->is_old(), "Unexpected dest region attr: %s", dest->get_type_str());
346 // no other space to try.
347 return NULL;
348 }
349 }
350
351 G1HeapRegionAttr G1ParScanThreadState::next_region_attr(G1HeapRegionAttr const region_attr, markWord const m, uint& age) {
352 if (region_attr.is_young()) {
353 age = !m.has_displaced_mark_helper() ? m.age()
354 : m.displaced_mark_helper().age();
355 if (age < _tenuring_threshold) {
356 return region_attr;
357 }
358 }
359 return dest(region_attr);
360 }
361
362 void G1ParScanThreadState::report_promotion_event(G1HeapRegionAttr const dest_attr,
363 Klass* klass, size_t word_sz, uint age,
364 HeapWord * const obj_ptr, uint node_index) const {
365 PLAB* alloc_buf = _plab_allocator->alloc_buffer(dest_attr, node_index);
366 if (alloc_buf->contains(obj_ptr)) {
367 _g1h->_gc_tracer_stw->report_promotion_in_new_plab_event(klass, word_sz * HeapWordSize, age,
368 dest_attr.type() == G1HeapRegionAttr::Old,
369 alloc_buf->word_sz() * HeapWordSize);
370 } else {
371 _g1h->_gc_tracer_stw->report_promotion_outside_plab_event(klass, word_sz * HeapWordSize, age,
372 dest_attr.type() == G1HeapRegionAttr::Old);
373 }
374 }
375
376 NOINLINE
377 HeapWord* G1ParScanThreadState::allocate_copy_slow(G1HeapRegionAttr* dest_attr,
378 Klass* klass,
379 size_t word_sz,
380 uint age,
381 uint node_index) {
382 HeapWord* obj_ptr = NULL;
383 // Try slow-path allocation unless we're allocating old and old is already full.
384 if (!(dest_attr->is_old() && _old_gen_is_full)) {
385 bool plab_refill_failed = false;
386 obj_ptr = _plab_allocator->allocate_direct_or_new_plab(*dest_attr,
387 word_sz,
388 &plab_refill_failed,
389 node_index);
390 if (obj_ptr == NULL) {
391 obj_ptr = allocate_in_next_plab(dest_attr,
392 word_sz,
393 plab_refill_failed,
394 node_index);
395 }
396 }
397 if (obj_ptr != NULL) {
398 update_numa_stats(node_index);
399 if (_g1h->_gc_tracer_stw->should_report_promotion_events()) {
400 // The events are checked individually as part of the actual commit
401 report_promotion_event(*dest_attr, klass, word_sz, age, obj_ptr, node_index);
402 }
403 }
404 return obj_ptr;
405 }
406
407 NOINLINE
408 void G1ParScanThreadState::undo_allocation(G1HeapRegionAttr dest_attr,
409 HeapWord* obj_ptr,
410 size_t word_sz,
411 uint node_index) {
412 _plab_allocator->undo_allocation(dest_attr, obj_ptr, word_sz, node_index);
413 }
414
415 // Private inline function, for direct internal use and providing the
416 // implementation of the public not-inline function.
417 MAYBE_INLINE_EVACUATION
418 oop G1ParScanThreadState::do_copy_to_survivor_space(G1HeapRegionAttr const region_attr,
419 oop const old,
420 markWord const old_mark) {
421 assert(region_attr.is_in_cset(),
422 "Unexpected region attr type: %s", region_attr.get_type_str());
423
424 // Get the klass once. We'll need it again later, and this avoids
425 // re-decoding when it's compressed.
426 // NOTE: With compact headers, it is not safe to load the Klass* from o, because
427 // that would access the mark-word, and the mark-word might change at any time by
428 // concurrent promotion. The promoted mark-word would point to the forwardee, which
429 // may not yet have completed copying. Therefore we must load the Klass* from
430 // the mark-word that we have already loaded. This is safe, because we have checked
431 // that this is not yet forwarded in the caller.
432 Klass* klass = old->forward_safe_klass(old_mark);
433 const size_t word_sz = old->size_given_klass(klass);
434
435 uint age = 0;
436 G1HeapRegionAttr dest_attr = next_region_attr(region_attr, old_mark, age);
437 HeapRegion* const from_region = _g1h->heap_region_containing(old);
438 uint node_index = from_region->node_index();
439
440 HeapWord* obj_ptr = _plab_allocator->plab_allocate(dest_attr, word_sz, node_index);
441
442 // PLAB allocations should succeed most of the time, so we'll
443 // normally check against NULL once and that's it.
444 if (obj_ptr == NULL) {
445 obj_ptr = allocate_copy_slow(&dest_attr, klass, word_sz, age, node_index);
446 if (obj_ptr == NULL) {
447 // This will either forward-to-self, or detect that someone else has
448 // installed a forwarding pointer.
449 return handle_evacuation_failure_par(old, old_mark);
450 }
451 }
452
453 assert(obj_ptr != NULL, "when we get here, allocation should have succeeded");
454 assert(_g1h->is_in_reserved(obj_ptr), "Allocated memory should be in the heap");
455
456 #ifndef PRODUCT
457 // Should this evacuation fail?
458 if (_g1h->evacuation_should_fail()) {
459 // Doing this after all the allocation attempts also tests the
460 // undo_allocation() method too.
461 undo_allocation(dest_attr, obj_ptr, word_sz, node_index);
462 return handle_evacuation_failure_par(old, old_mark);
463 }
464 #endif // !PRODUCT
465
466 // We're going to allocate linearly, so might as well prefetch ahead.
467 Prefetch::write(obj_ptr, PrefetchCopyIntervalInBytes);
468
469 const oop obj = cast_to_oop(obj_ptr);
470 const oop forward_ptr = old->forward_to_atomic(obj, old_mark, memory_order_relaxed);
471 if (forward_ptr == NULL) {
472 Copy::aligned_disjoint_words(cast_from_oop<HeapWord*>(old), obj_ptr, word_sz);
473
474 {
475 const uint young_index = from_region->young_index_in_cset();
476 assert((from_region->is_young() && young_index > 0) ||
477 (!from_region->is_young() && young_index == 0), "invariant" );
478 _surviving_young_words[young_index] += word_sz;
479 }
480
481 if (dest_attr.is_young()) {
482 if (age < markWord::max_age) {
483 age++;
484 }
485 if (old_mark.has_displaced_mark_helper()) {
486 // In this case, we have to install the old mark word containing the
487 // displacement tag, and update the age in the displaced mark word.
488 markWord new_mark = old_mark.displaced_mark_helper().set_age(age);
489 old_mark.set_displaced_mark_helper(new_mark);
490 obj->set_mark(old_mark);
491 } else {
492 obj->set_mark(old_mark.set_age(age));
493 }
494 _age_table.add(age, word_sz);
495 } else {
496 obj->set_mark(old_mark);
497 }
498
499 // Most objects are not arrays, so do one array check rather than
500 // checking for each array category for each object.
501 if (klass->is_array_klass()) {
502 if (klass->is_objArray_klass()) {
503 start_partial_objarray(dest_attr, old, obj);
504 } else {
505 // Nothing needs to be done for typeArrays. Body doesn't contain
506 // any oops to scan, and the type in the klass will already be handled
507 // by processing the built-in module.
508 assert(klass->is_typeArray_klass(), "invariant");
509 }
510 return obj;
511 }
512
513 // Check for deduplicating young Strings.
514 if (G1StringDedup::is_candidate_from_evacuation(klass,
515 region_attr,
516 dest_attr,
517 age)) {
518 // Record old; request adds a new weak reference, which reference
519 // processing expects to refer to a from-space object.
520 _string_dedup_requests.add(old);
521 }
522
523 G1ScanInYoungSetter x(&_scanner, dest_attr.is_young());
524 obj->oop_iterate_backwards(&_scanner, klass);
525 return obj;
526
527 } else {
528 _plab_allocator->undo_allocation(dest_attr, obj_ptr, word_sz, node_index);
529 return forward_ptr;
530 }
531 }
532
533 // Public not-inline entry point.
534 ATTRIBUTE_FLATTEN
535 oop G1ParScanThreadState::copy_to_survivor_space(G1HeapRegionAttr region_attr,
536 oop old,
537 markWord old_mark) {
538 return do_copy_to_survivor_space(region_attr, old, old_mark);
539 }
540
541 G1ParScanThreadState* G1ParScanThreadStateSet::state_for_worker(uint worker_id) {
542 assert(worker_id < _n_workers, "out of bounds access");
543 if (_states[worker_id] == NULL) {
544 _states[worker_id] =
545 new G1ParScanThreadState(_g1h, _rdcqs,
546 worker_id, _n_workers,
547 _young_cset_length, _optional_cset_length);
548 }
549 return _states[worker_id];
550 }
551
552 const size_t* G1ParScanThreadStateSet::surviving_young_words() const {
553 assert(_flushed, "thread local state from the per thread states should have been flushed");
554 return _surviving_young_words_total;
555 }
556
557 void G1ParScanThreadStateSet::flush() {
558 assert(!_flushed, "thread local state from the per thread states should be flushed once");
559
560 for (uint worker_id = 0; worker_id < _n_workers; ++worker_id) {
561 G1ParScanThreadState* pss = _states[worker_id];
562
563 if (pss == NULL) {
564 continue;
565 }
566
567 G1GCPhaseTimes* p = _g1h->phase_times();
568
569 // Need to get the following two before the call to G1ParThreadScanState::flush()
570 // because it resets the PLAB allocator where we get this info from.
571 size_t lab_waste_bytes = pss->lab_waste_words() * HeapWordSize;
572 size_t lab_undo_waste_bytes = pss->lab_undo_waste_words() * HeapWordSize;
573 size_t copied_bytes = pss->flush(_surviving_young_words_total) * HeapWordSize;
574
575 p->record_or_add_thread_work_item(G1GCPhaseTimes::MergePSS, worker_id, copied_bytes, G1GCPhaseTimes::MergePSSCopiedBytes);
576 p->record_or_add_thread_work_item(G1GCPhaseTimes::MergePSS, worker_id, lab_waste_bytes, G1GCPhaseTimes::MergePSSLABWasteBytes);
577 p->record_or_add_thread_work_item(G1GCPhaseTimes::MergePSS, worker_id, lab_undo_waste_bytes, G1GCPhaseTimes::MergePSSLABUndoWasteBytes);
578
579 delete pss;
580 _states[worker_id] = NULL;
581 }
582 _flushed = true;
583 }
584
585 void G1ParScanThreadStateSet::record_unused_optional_region(HeapRegion* hr) {
586 for (uint worker_index = 0; worker_index < _n_workers; ++worker_index) {
587 G1ParScanThreadState* pss = _states[worker_index];
588
589 if (pss == NULL) {
590 continue;
591 }
592
593 size_t used_memory = pss->oops_into_optional_region(hr)->used_memory();
594 _g1h->phase_times()->record_or_add_thread_work_item(G1GCPhaseTimes::OptScanHR, worker_index, used_memory, G1GCPhaseTimes::ScanHRUsedMemory);
595 }
596 }
597
598 NOINLINE
599 oop G1ParScanThreadState::handle_evacuation_failure_par(oop old, markWord m) {
600 assert(_g1h->is_in_cset(old), "Object " PTR_FORMAT " should be in the CSet", p2i(old));
601
602 oop forward_ptr = old->forward_to_self_atomic(m, memory_order_relaxed);
603 if (forward_ptr == NULL) {
604 // Forward-to-self succeeded. We are the "owner" of the object.
605 HeapRegion* r = _g1h->heap_region_containing(old);
606
607 if (_g1h->notify_region_failed_evacuation(r->hrm_index())) {
608 _g1h->hr_printer()->evac_failure(r);
609 }
610
611 _g1h->preserve_mark_during_evac_failure(_worker_id, old, m);
612
613 G1ScanInYoungSetter x(&_scanner, r->is_young());
614 old->oop_iterate_backwards(&_scanner);
615
616 return old;
617 } else {
618 // Forward-to-self failed. Either someone else managed to allocate
619 // space for this object (old != forward_ptr) or they beat us in
620 // self-forwarding it (old == forward_ptr).
621 assert(old == forward_ptr || !_g1h->is_in_cset(forward_ptr),
622 "Object " PTR_FORMAT " forwarded to: " PTR_FORMAT " "
623 "should not be in the CSet",
624 p2i(old), p2i(forward_ptr));
625 return forward_ptr;
626 }
627 }
628
629 void G1ParScanThreadState::initialize_numa_stats() {
630 if (_numa->is_enabled()) {
631 LogTarget(Info, gc, heap, numa) lt;
632
633 if (lt.is_enabled()) {
634 uint num_nodes = _numa->num_active_nodes();
635 // Record only if there are multiple active nodes.
636 _obj_alloc_stat = NEW_C_HEAP_ARRAY(size_t, num_nodes, mtGC);
637 memset(_obj_alloc_stat, 0, sizeof(size_t) * num_nodes);
638 }
639 }
640 }
641
642 void G1ParScanThreadState::flush_numa_stats() {
643 if (_obj_alloc_stat != NULL) {
644 uint node_index = _numa->index_of_current_thread();
645 _numa->copy_statistics(G1NUMAStats::LocalObjProcessAtCopyToSurv, node_index, _obj_alloc_stat);
646 }
647 }
648
649 void G1ParScanThreadState::update_numa_stats(uint node_index) {
650 if (_obj_alloc_stat != NULL) {
651 _obj_alloc_stat[node_index]++;
652 }
653 }
654
655 G1ParScanThreadStateSet::G1ParScanThreadStateSet(G1CollectedHeap* g1h,
656 G1RedirtyCardsQueueSet* rdcqs,
657 uint n_workers,
658 size_t young_cset_length,
659 size_t optional_cset_length) :
660 _g1h(g1h),
661 _rdcqs(rdcqs),
662 _states(NEW_C_HEAP_ARRAY(G1ParScanThreadState*, n_workers, mtGC)),
663 _surviving_young_words_total(NEW_C_HEAP_ARRAY(size_t, young_cset_length + 1, mtGC)),
664 _young_cset_length(young_cset_length),
665 _optional_cset_length(optional_cset_length),
666 _n_workers(n_workers),
667 _flushed(false) {
668 for (uint i = 0; i < n_workers; ++i) {
669 _states[i] = NULL;
670 }
671 memset(_surviving_young_words_total, 0, (young_cset_length + 1) * sizeof(size_t));
672 }
673
674 G1ParScanThreadStateSet::~G1ParScanThreadStateSet() {
675 assert(_flushed, "thread local state from the per thread states should have been flushed");
676 FREE_C_HEAP_ARRAY(G1ParScanThreadState*, _states);
677 FREE_C_HEAP_ARRAY(size_t, _surviving_young_words_total);
678 }