1 /*
2 * Copyright (c) 2001, 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 "code/nmethod.hpp"
27 #include "gc/g1/g1Allocator.inline.hpp"
28 #include "gc/g1/g1BlockOffsetTable.inline.hpp"
29 #include "gc/g1/g1CollectedHeap.inline.hpp"
30 #include "gc/g1/g1CollectionSet.hpp"
31 #include "gc/g1/g1HeapRegionTraceType.hpp"
32 #include "gc/g1/g1NUMA.hpp"
33 #include "gc/g1/g1OopClosures.inline.hpp"
34 #include "gc/g1/heapRegion.inline.hpp"
35 #include "gc/g1/heapRegionBounds.inline.hpp"
36 #include "gc/g1/heapRegionManager.inline.hpp"
37 #include "gc/g1/heapRegionRemSet.hpp"
38 #include "gc/g1/heapRegionTracer.hpp"
39 #include "gc/shared/genOopClosures.inline.hpp"
40 #include "logging/log.hpp"
41 #include "logging/logStream.hpp"
42 #include "memory/iterator.inline.hpp"
43 #include "memory/resourceArea.hpp"
44 #include "oops/access.inline.hpp"
45 #include "oops/compressedOops.inline.hpp"
46 #include "oops/oop.inline.hpp"
47 #include "runtime/globals_extension.hpp"
48 #include "utilities/powerOfTwo.hpp"
49
50 int HeapRegion::LogOfHRGrainBytes = 0;
51 int HeapRegion::LogCardsPerRegion = 0;
52 size_t HeapRegion::GrainBytes = 0;
53 size_t HeapRegion::GrainWords = 0;
54 size_t HeapRegion::CardsPerRegion = 0;
55
56 size_t HeapRegion::max_region_size() {
57 return HeapRegionBounds::max_size();
58 }
59
60 size_t HeapRegion::min_region_size_in_words() {
61 return HeapRegionBounds::min_size() >> LogHeapWordSize;
62 }
63
64 void HeapRegion::setup_heap_region_size(size_t max_heap_size) {
65 size_t region_size = G1HeapRegionSize;
66 // G1HeapRegionSize = 0 means decide ergonomically.
67 if (region_size == 0) {
68 region_size = MAX2(max_heap_size / HeapRegionBounds::target_number(),
69 HeapRegionBounds::min_size());
70 }
71
72 // Make sure region size is a power of 2. Rounding up since this
73 // is beneficial in most cases.
74 region_size = round_up_power_of_2(region_size);
75
76 // Now make sure that we don't go over or under our limits.
77 region_size = clamp(region_size, HeapRegionBounds::min_size(), HeapRegionBounds::max_size());
78
79 // Calculate the log for the region size.
80 int region_size_log = log2i_exact(region_size);
81
82 // Now, set up the globals.
83 guarantee(LogOfHRGrainBytes == 0, "we should only set it once");
84 LogOfHRGrainBytes = region_size_log;
85
86 guarantee(GrainBytes == 0, "we should only set it once");
87 // The cast to int is safe, given that we've bounded region_size by
88 // MIN_REGION_SIZE and MAX_REGION_SIZE.
89 GrainBytes = region_size;
90
91 guarantee(GrainWords == 0, "we should only set it once");
92 GrainWords = GrainBytes >> LogHeapWordSize;
93
94 guarantee(CardsPerRegion == 0, "we should only set it once");
95 CardsPerRegion = GrainBytes >> G1CardTable::card_shift;
96
97 LogCardsPerRegion = log2i(CardsPerRegion);
98
99 if (G1HeapRegionSize != GrainBytes) {
100 FLAG_SET_ERGO(G1HeapRegionSize, GrainBytes);
101 }
102 }
103
104 void HeapRegion::handle_evacuation_failure() {
105 uninstall_surv_rate_group();
106 clear_young_index_in_cset();
107 set_old();
108 _next_marked_bytes = 0;
109 }
110
111 void HeapRegion::unlink_from_list() {
112 set_next(NULL);
113 set_prev(NULL);
114 set_containing_set(NULL);
115 }
116
117 void HeapRegion::hr_clear(bool clear_space) {
118 assert(_humongous_start_region == NULL,
119 "we should have already filtered out humongous regions");
120
121 clear_young_index_in_cset();
122 clear_index_in_opt_cset();
123 uninstall_surv_rate_group();
124 set_free();
125 reset_pre_dummy_top();
126
127 rem_set()->clear_locked();
128
129 zero_marked_bytes();
130
131 init_top_at_mark_start();
132 if (clear_space) clear(SpaceDecorator::Mangle);
133
134 _gc_efficiency = -1.0;
135 }
136
137 void HeapRegion::clear_cardtable() {
138 G1CardTable* ct = G1CollectedHeap::heap()->card_table();
139 ct->clear(MemRegion(bottom(), end()));
140 }
141
142 void HeapRegion::calc_gc_efficiency() {
143 // GC efficiency is the ratio of how much space would be
144 // reclaimed over how long we predict it would take to reclaim it.
145 G1Policy* policy = G1CollectedHeap::heap()->policy();
146
147 // Retrieve a prediction of the elapsed time for this region for
148 // a mixed gc because the region will only be evacuated during a
149 // mixed gc.
150 double region_elapsed_time_ms = policy->predict_region_total_time_ms(this, false /* for_young_gc */);
151 _gc_efficiency = (double) reclaimable_bytes() / region_elapsed_time_ms;
152 }
153
154 void HeapRegion::set_free() {
155 report_region_type_change(G1HeapRegionTraceType::Free);
156 _type.set_free();
157 }
158
159 void HeapRegion::set_eden() {
160 report_region_type_change(G1HeapRegionTraceType::Eden);
161 _type.set_eden();
162 }
163
164 void HeapRegion::set_eden_pre_gc() {
165 report_region_type_change(G1HeapRegionTraceType::Eden);
166 _type.set_eden_pre_gc();
167 }
168
169 void HeapRegion::set_survivor() {
170 report_region_type_change(G1HeapRegionTraceType::Survivor);
171 _type.set_survivor();
172 }
173
174 void HeapRegion::move_to_old() {
175 if (_type.relabel_as_old()) {
176 report_region_type_change(G1HeapRegionTraceType::Old);
177 }
178 }
179
180 void HeapRegion::set_old() {
181 report_region_type_change(G1HeapRegionTraceType::Old);
182 _type.set_old();
183 }
184
185 void HeapRegion::set_open_archive() {
186 report_region_type_change(G1HeapRegionTraceType::OpenArchive);
187 _type.set_open_archive();
188 }
189
190 void HeapRegion::set_closed_archive() {
191 report_region_type_change(G1HeapRegionTraceType::ClosedArchive);
192 _type.set_closed_archive();
193 }
194
195 void HeapRegion::set_starts_humongous(HeapWord* obj_top, size_t fill_size) {
196 assert(!is_humongous(), "sanity / pre-condition");
197 assert(top() == bottom(), "should be empty");
198
199 report_region_type_change(G1HeapRegionTraceType::StartsHumongous);
200 _type.set_starts_humongous();
201 _humongous_start_region = this;
202
203 _bot_part.set_for_starts_humongous(obj_top, fill_size);
204 }
205
206 void HeapRegion::set_continues_humongous(HeapRegion* first_hr) {
207 assert(!is_humongous(), "sanity / pre-condition");
208 assert(top() == bottom(), "should be empty");
209 assert(first_hr->is_starts_humongous(), "pre-condition");
210
211 report_region_type_change(G1HeapRegionTraceType::ContinuesHumongous);
212 _type.set_continues_humongous();
213 _humongous_start_region = first_hr;
214
215 _bot_part.set_object_can_span(true);
216 }
217
218 void HeapRegion::clear_humongous() {
219 assert(is_humongous(), "pre-condition");
220
221 assert(capacity() == HeapRegion::GrainBytes, "pre-condition");
222 _humongous_start_region = NULL;
223
224 _bot_part.set_object_can_span(false);
225 }
226
227 HeapRegion::HeapRegion(uint hrm_index,
228 G1BlockOffsetTable* bot,
229 MemRegion mr) :
230 _bottom(mr.start()),
231 _end(mr.end()),
232 _top(NULL),
233 _compaction_top(NULL),
234 _bot_part(bot, this),
235 _par_alloc_lock(Mutex::leaf, "HeapRegion par alloc lock", true),
236 _pre_dummy_top(NULL),
237 _rem_set(NULL),
238 _hrm_index(hrm_index),
239 _type(),
240 _humongous_start_region(NULL),
241 _index_in_opt_cset(InvalidCSetIndex),
242 _next(NULL), _prev(NULL),
243 #ifdef ASSERT
244 _containing_set(NULL),
245 #endif
246 _prev_top_at_mark_start(NULL), _next_top_at_mark_start(NULL),
247 _prev_marked_bytes(0), _next_marked_bytes(0),
248 _young_index_in_cset(-1),
249 _surv_rate_group(NULL), _age_index(G1SurvRateGroup::InvalidAgeIndex), _gc_efficiency(-1.0),
250 _node_index(G1NUMA::UnknownNodeIndex)
251 {
252 assert(Universe::on_page_boundary(mr.start()) && Universe::on_page_boundary(mr.end()),
253 "invalid space boundaries");
254
255 _rem_set = new HeapRegionRemSet(bot, this);
256 initialize();
257 }
258
259 void HeapRegion::initialize(bool clear_space, bool mangle_space) {
260 assert(_rem_set->is_empty(), "Remembered set must be empty");
261
262 if (clear_space) {
263 clear(mangle_space);
264 }
265
266 set_top(bottom());
267 set_compaction_top(bottom());
268 reset_bot();
269
270 hr_clear(false /*clear_space*/);
271 }
272
273 void HeapRegion::report_region_type_change(G1HeapRegionTraceType::Type to) {
274 HeapRegionTracer::send_region_type_change(_hrm_index,
275 get_trace_type(),
276 to,
277 (uintptr_t)bottom(),
278 used());
279 }
280
281 void HeapRegion::note_self_forwarding_removal_start(bool during_concurrent_start,
282 bool during_conc_mark) {
283 // We always recreate the prev marking info and we'll explicitly
284 // mark all objects we find to be self-forwarded on the prev
285 // bitmap. So all objects need to be below PTAMS.
286 _prev_marked_bytes = 0;
287
288 if (during_concurrent_start) {
289 // During concurrent start, we'll also explicitly mark all objects
290 // we find to be self-forwarded on the next bitmap. So all
291 // objects need to be below NTAMS.
292 _next_top_at_mark_start = top();
293 _next_marked_bytes = 0;
294 } else if (during_conc_mark) {
295 // During concurrent mark, all objects in the CSet (including
296 // the ones we find to be self-forwarded) are implicitly live.
297 // So all objects need to be above NTAMS.
298 _next_top_at_mark_start = bottom();
299 _next_marked_bytes = 0;
300 }
301 }
302
303 void HeapRegion::note_self_forwarding_removal_end(size_t marked_bytes) {
304 assert(marked_bytes <= used(),
305 "marked: " SIZE_FORMAT " used: " SIZE_FORMAT, marked_bytes, used());
306 _prev_top_at_mark_start = top();
307 _prev_marked_bytes = marked_bytes;
308 }
309
310 // Code roots support
311
312 void HeapRegion::add_strong_code_root(nmethod* nm) {
313 HeapRegionRemSet* hrrs = rem_set();
314 hrrs->add_strong_code_root(nm);
315 }
316
317 void HeapRegion::add_strong_code_root_locked(nmethod* nm) {
318 assert_locked_or_safepoint(CodeCache_lock);
319 HeapRegionRemSet* hrrs = rem_set();
320 hrrs->add_strong_code_root_locked(nm);
321 }
322
323 void HeapRegion::remove_strong_code_root(nmethod* nm) {
324 HeapRegionRemSet* hrrs = rem_set();
325 hrrs->remove_strong_code_root(nm);
326 }
327
328 void HeapRegion::strong_code_roots_do(CodeBlobClosure* blk) const {
329 HeapRegionRemSet* hrrs = rem_set();
330 hrrs->strong_code_roots_do(blk);
331 }
332
333 class VerifyStrongCodeRootOopClosure: public OopClosure {
334 const HeapRegion* _hr;
335 bool _failures;
336 bool _has_oops_in_region;
337
338 template <class T> void do_oop_work(T* p) {
339 T heap_oop = RawAccess<>::oop_load(p);
340 if (!CompressedOops::is_null(heap_oop)) {
341 oop obj = CompressedOops::decode_not_null(heap_oop);
342
343 // Note: not all the oops embedded in the nmethod are in the
344 // current region. We only look at those which are.
345 if (_hr->is_in(obj)) {
346 // Object is in the region. Check that its less than top
347 if (_hr->top() <= cast_from_oop<HeapWord*>(obj)) {
348 // Object is above top
349 log_error(gc, verify)("Object " PTR_FORMAT " in region " HR_FORMAT " is above top ",
350 p2i(obj), HR_FORMAT_PARAMS(_hr));
351 _failures = true;
352 return;
353 }
354 // Nmethod has at least one oop in the current region
355 _has_oops_in_region = true;
356 }
357 }
358 }
359
360 public:
361 VerifyStrongCodeRootOopClosure(const HeapRegion* hr):
362 _hr(hr), _failures(false), _has_oops_in_region(false) {}
363
364 void do_oop(narrowOop* p) { do_oop_work(p); }
365 void do_oop(oop* p) { do_oop_work(p); }
366
367 bool failures() { return _failures; }
368 bool has_oops_in_region() { return _has_oops_in_region; }
369 };
370
371 class VerifyStrongCodeRootCodeBlobClosure: public CodeBlobClosure {
372 const HeapRegion* _hr;
373 bool _failures;
374 public:
375 VerifyStrongCodeRootCodeBlobClosure(const HeapRegion* hr) :
376 _hr(hr), _failures(false) {}
377
378 void do_code_blob(CodeBlob* cb) {
379 nmethod* nm = (cb == NULL) ? NULL : cb->as_compiled_method()->as_nmethod_or_null();
380 if (nm != NULL) {
381 // Verify that the nemthod is live
382 if (!nm->is_alive()) {
383 log_error(gc, verify)("region [" PTR_FORMAT "," PTR_FORMAT "] has dead nmethod " PTR_FORMAT " in its strong code roots",
384 p2i(_hr->bottom()), p2i(_hr->end()), p2i(nm));
385 _failures = true;
386 } else {
387 VerifyStrongCodeRootOopClosure oop_cl(_hr);
388 nm->oops_do(&oop_cl);
389 if (!oop_cl.has_oops_in_region()) {
390 log_error(gc, verify)("region [" PTR_FORMAT "," PTR_FORMAT "] has nmethod " PTR_FORMAT " in its strong code roots with no pointers into region",
391 p2i(_hr->bottom()), p2i(_hr->end()), p2i(nm));
392 _failures = true;
393 } else if (oop_cl.failures()) {
394 log_error(gc, verify)("region [" PTR_FORMAT "," PTR_FORMAT "] has other failures for nmethod " PTR_FORMAT,
395 p2i(_hr->bottom()), p2i(_hr->end()), p2i(nm));
396 _failures = true;
397 }
398 }
399 }
400 }
401
402 bool failures() { return _failures; }
403 };
404
405 void HeapRegion::verify_strong_code_roots(VerifyOption vo, bool* failures) const {
406 if (!G1VerifyHeapRegionCodeRoots) {
407 // We're not verifying code roots.
408 return;
409 }
410 if (vo == VerifyOption_G1UseFullMarking) {
411 // Marking verification during a full GC is performed after class
412 // unloading, code cache unloading, etc so the strong code roots
413 // attached to each heap region are in an inconsistent state. They won't
414 // be consistent until the strong code roots are rebuilt after the
415 // actual GC. Skip verifying the strong code roots in this particular
416 // time.
417 assert(VerifyDuringGC, "only way to get here");
418 return;
419 }
420
421 HeapRegionRemSet* hrrs = rem_set();
422 size_t strong_code_roots_length = hrrs->strong_code_roots_list_length();
423
424 // if this region is empty then there should be no entries
425 // on its strong code root list
426 if (is_empty()) {
427 if (strong_code_roots_length > 0) {
428 log_error(gc, verify)("region " HR_FORMAT " is empty but has " SIZE_FORMAT " code root entries",
429 HR_FORMAT_PARAMS(this), strong_code_roots_length);
430 *failures = true;
431 }
432 return;
433 }
434
435 if (is_continues_humongous()) {
436 if (strong_code_roots_length > 0) {
437 log_error(gc, verify)("region " HR_FORMAT " is a continuation of a humongous region but has " SIZE_FORMAT " code root entries",
438 HR_FORMAT_PARAMS(this), strong_code_roots_length);
439 *failures = true;
440 }
441 return;
442 }
443
444 VerifyStrongCodeRootCodeBlobClosure cb_cl(this);
445 strong_code_roots_do(&cb_cl);
446
447 if (cb_cl.failures()) {
448 *failures = true;
449 }
450 }
451
452 void HeapRegion::print() const { print_on(tty); }
453
454 void HeapRegion::print_on(outputStream* st) const {
455 st->print("|%4u", this->_hrm_index);
456 st->print("|" PTR_FORMAT ", " PTR_FORMAT ", " PTR_FORMAT,
457 p2i(bottom()), p2i(top()), p2i(end()));
458 st->print("|%3d%%", (int) ((double) used() * 100 / capacity()));
459 st->print("|%2s", get_short_type_str());
460 if (in_collection_set()) {
461 st->print("|CS");
462 } else {
463 st->print("| ");
464 }
465 st->print("|TAMS " PTR_FORMAT ", " PTR_FORMAT "| %s ",
466 p2i(prev_top_at_mark_start()), p2i(next_top_at_mark_start()), rem_set()->get_state_str());
467 if (UseNUMA) {
468 G1NUMA* numa = G1NUMA::numa();
469 if (node_index() < numa->num_active_nodes()) {
470 st->print("|%d", numa->numa_id(node_index()));
471 } else {
472 st->print("|-");
473 }
474 }
475 st->print_cr("");
476 }
477
478 class G1VerificationClosure : public BasicOopIterateClosure {
479 protected:
480 G1CollectedHeap* _g1h;
481 G1CardTable *_ct;
482 oop _containing_obj;
483 bool _failures;
484 int _n_failures;
485 VerifyOption _vo;
486 public:
487 // _vo == UsePrevMarking -> use "prev" marking information,
488 // _vo == UseNextMarking -> use "next" marking information,
489 // _vo == UseFullMarking -> use "next" marking bitmap but no TAMS.
490 G1VerificationClosure(G1CollectedHeap* g1h, VerifyOption vo) :
491 _g1h(g1h), _ct(g1h->card_table()),
492 _containing_obj(NULL), _failures(false), _n_failures(0), _vo(vo) {
493 }
494
495 void set_containing_obj(oop obj) {
496 _containing_obj = obj;
497 }
498
499 bool failures() { return _failures; }
500 int n_failures() { return _n_failures; }
501
502 void print_object(outputStream* out, oop obj) {
503 #ifdef PRODUCT
504 Klass* k = obj->klass();
505 const char* class_name = k->external_name();
506 out->print_cr("class name %s", class_name);
507 #else // PRODUCT
508 obj->print_on(out);
509 #endif // PRODUCT
510 }
511 };
512
513 class VerifyLiveClosure : public G1VerificationClosure {
514 public:
515 VerifyLiveClosure(G1CollectedHeap* g1h, VerifyOption vo) : G1VerificationClosure(g1h, vo) {}
516 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
517 virtual void do_oop(oop* p) { do_oop_work(p); }
518
519 template <class T>
520 void do_oop_work(T* p) {
521 assert(_containing_obj != NULL, "Precondition");
522 assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo),
523 "Precondition");
524 verify_liveness(p);
525 }
526
527 template <class T>
528 void verify_liveness(T* p) {
529 T heap_oop = RawAccess<>::oop_load(p);
530 Log(gc, verify) log;
531 if (!CompressedOops::is_null(heap_oop)) {
532 oop obj = CompressedOops::decode_not_null(heap_oop);
533 bool failed = false;
534 if (!_g1h->is_in(obj) || _g1h->is_obj_dead_cond(obj, _vo)) {
535 MutexLocker x(ParGCRareEvent_lock,
536 Mutex::_no_safepoint_check_flag);
537
538 if (!_failures) {
539 log.error("----------");
540 }
541 ResourceMark rm;
542 if (!_g1h->is_in(obj)) {
543 HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
544 log.error("Field " PTR_FORMAT " of live obj " PTR_FORMAT " in region " HR_FORMAT,
545 p2i(p), p2i(_containing_obj), HR_FORMAT_PARAMS(from));
546 LogStream ls(log.error());
547 print_object(&ls, _containing_obj);
548 HeapRegion* const to = _g1h->heap_region_containing(obj);
549 log.error("points to obj " PTR_FORMAT " in region " HR_FORMAT " remset %s",
550 p2i(obj), HR_FORMAT_PARAMS(to), to->rem_set()->get_state_str());
551 } else {
552 HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
553 HeapRegion* to = _g1h->heap_region_containing(obj);
554 log.error("Field " PTR_FORMAT " of live obj " PTR_FORMAT " in region " HR_FORMAT,
555 p2i(p), p2i(_containing_obj), HR_FORMAT_PARAMS(from));
556 LogStream ls(log.error());
557 print_object(&ls, _containing_obj);
558 log.error("points to dead obj " PTR_FORMAT " in region " HR_FORMAT,
559 p2i(obj), HR_FORMAT_PARAMS(to));
560 print_object(&ls, obj);
561 }
562 log.error("----------");
563 _failures = true;
564 failed = true;
565 _n_failures++;
566 }
567 }
568 }
569 };
570
571 class VerifyRemSetClosure : public G1VerificationClosure {
572 public:
573 VerifyRemSetClosure(G1CollectedHeap* g1h, VerifyOption vo) : G1VerificationClosure(g1h, vo) {}
574 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
575 virtual void do_oop(oop* p) { do_oop_work(p); }
576
577 template <class T>
578 void do_oop_work(T* p) {
579 assert(_containing_obj != NULL, "Precondition");
580 assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo),
581 "Precondition");
582 verify_remembered_set(p);
583 }
584
585 template <class T>
586 void verify_remembered_set(T* p) {
587 T heap_oop = RawAccess<>::oop_load(p);
588 Log(gc, verify) log;
589 if (!CompressedOops::is_null(heap_oop)) {
590 oop obj = CompressedOops::decode_not_null(heap_oop);
591 HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
592 HeapRegion* to = _g1h->heap_region_containing(obj);
593 if (from != NULL && to != NULL &&
594 from != to &&
595 !to->is_pinned() &&
596 to->rem_set()->is_complete()) {
597 jbyte cv_obj = *_ct->byte_for_const(_containing_obj);
598 jbyte cv_field = *_ct->byte_for_const(p);
599 const jbyte dirty = G1CardTable::dirty_card_val();
600
601 bool is_bad = !(from->is_young()
602 || to->rem_set()->contains_reference(p)
603 || (_containing_obj->is_objArray() ?
604 cv_field == dirty :
605 cv_obj == dirty || cv_field == dirty));
606 if (is_bad) {
607 MutexLocker x(ParGCRareEvent_lock,
608 Mutex::_no_safepoint_check_flag);
609
610 if (!_failures) {
611 log.error("----------");
612 }
613 log.error("Missing rem set entry:");
614 log.error("Field " PTR_FORMAT " of obj " PTR_FORMAT " in region " HR_FORMAT,
615 p2i(p), p2i(_containing_obj), HR_FORMAT_PARAMS(from));
616 ResourceMark rm;
617 LogStream ls(log.error());
618 _containing_obj->print_on(&ls);
619 log.error("points to obj " PTR_FORMAT " in region " HR_FORMAT " remset %s",
620 p2i(obj), HR_FORMAT_PARAMS(to), to->rem_set()->get_state_str());
621 if (oopDesc::is_oop(obj)) {
622 obj->print_on(&ls);
623 }
624 log.error("Obj head CTE = %d, field CTE = %d.", cv_obj, cv_field);
625 log.error("----------");
626 _failures = true;
627 _n_failures++;
628 }
629 }
630 }
631 }
632 };
633
634 // Closure that applies the given two closures in sequence.
635 class G1Mux2Closure : public BasicOopIterateClosure {
636 OopClosure* _c1;
637 OopClosure* _c2;
638 public:
639 G1Mux2Closure(OopClosure *c1, OopClosure *c2) { _c1 = c1; _c2 = c2; }
640 template <class T> inline void do_oop_work(T* p) {
641 // Apply first closure; then apply the second.
642 _c1->do_oop(p);
643 _c2->do_oop(p);
644 }
645 virtual inline void do_oop(oop* p) { do_oop_work(p); }
646 virtual inline void do_oop(narrowOop* p) { do_oop_work(p); }
647 };
648
649 void HeapRegion::verify(VerifyOption vo,
650 bool* failures) const {
651 G1CollectedHeap* g1h = G1CollectedHeap::heap();
652 *failures = false;
653 HeapWord* p = bottom();
654 HeapWord* prev_p = NULL;
655 VerifyLiveClosure vl_cl(g1h, vo);
656 VerifyRemSetClosure vr_cl(g1h, vo);
657 bool is_region_humongous = is_humongous();
658 size_t object_num = 0;
659 while (p < top()) {
660 oop obj = cast_to_oop(p);
661 size_t obj_size = block_size(p);
662 object_num += 1;
663
664 if (!g1h->is_obj_dead_cond(obj, this, vo)) {
665 if (oopDesc::is_oop(obj)) {
666 Klass* klass = obj->klass();
667 bool is_metaspace_object = Metaspace::contains(klass);
668 if (!is_metaspace_object) {
669 log_error(gc, verify)("klass " PTR_FORMAT " of object " PTR_FORMAT " "
670 "not metadata", p2i(klass), p2i(obj));
671 *failures = true;
672 return;
673 } else if (!klass->is_klass()) {
674 log_error(gc, verify)("klass " PTR_FORMAT " of object " PTR_FORMAT " "
675 "not a klass", p2i(klass), p2i(obj));
676 *failures = true;
677 return;
678 } else {
679 vl_cl.set_containing_obj(obj);
680 if (!g1h->collector_state()->in_full_gc() || G1VerifyRSetsDuringFullGC) {
681 // verify liveness and rem_set
682 vr_cl.set_containing_obj(obj);
683 G1Mux2Closure mux(&vl_cl, &vr_cl);
684 obj->oop_iterate(&mux);
685
686 if (vr_cl.failures()) {
687 *failures = true;
688 }
689 if (G1MaxVerifyFailures >= 0 &&
690 vr_cl.n_failures() >= G1MaxVerifyFailures) {
691 return;
692 }
693 } else {
694 // verify only liveness
695 obj->oop_iterate(&vl_cl);
696 }
697 if (vl_cl.failures()) {
698 *failures = true;
699 }
700 if (G1MaxVerifyFailures >= 0 &&
701 vl_cl.n_failures() >= G1MaxVerifyFailures) {
702 return;
703 }
704 }
705 } else {
706 log_error(gc, verify)(PTR_FORMAT " not an oop", p2i(obj));
707 *failures = true;
708 return;
709 }
710 }
711 prev_p = p;
712 p += obj_size;
713 }
714
715 if (!is_empty()) {
716 _bot_part.verify();
717 }
718
719 if (is_region_humongous) {
720 oop obj = cast_to_oop(this->humongous_start_region()->bottom());
721 if (cast_from_oop<HeapWord*>(obj) > bottom() || cast_from_oop<HeapWord*>(obj) + obj->size() < bottom()) {
722 log_error(gc, verify)("this humongous region is not part of its' humongous object " PTR_FORMAT, p2i(obj));
723 *failures = true;
724 return;
725 }
726 }
727
728 if (!is_region_humongous && p != top()) {
729 log_error(gc, verify)("end of last object " PTR_FORMAT " "
730 "does not match top " PTR_FORMAT, p2i(p), p2i(top()));
731 *failures = true;
732 return;
733 }
734
735 HeapWord* the_end = end();
736 // Do some extra BOT consistency checking for addresses in the
737 // range [top, end). BOT look-ups in this range should yield
738 // top. No point in doing that if top == end (there's nothing there).
739 if (p < the_end) {
740 // Look up top
741 HeapWord* addr_1 = p;
742 HeapWord* b_start_1 = block_start_const(addr_1);
743 if (b_start_1 != p) {
744 log_error(gc, verify)("BOT look up for top: " PTR_FORMAT " "
745 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
746 p2i(addr_1), p2i(b_start_1), p2i(p));
747 *failures = true;
748 return;
749 }
750
751 // Look up top + 1
752 HeapWord* addr_2 = p + 1;
753 if (addr_2 < the_end) {
754 HeapWord* b_start_2 = block_start_const(addr_2);
755 if (b_start_2 != p) {
756 log_error(gc, verify)("BOT look up for top + 1: " PTR_FORMAT " "
757 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
758 p2i(addr_2), p2i(b_start_2), p2i(p));
759 *failures = true;
760 return;
761 }
762 }
763
764 // Look up an address between top and end
765 size_t diff = pointer_delta(the_end, p) / 2;
766 HeapWord* addr_3 = p + diff;
767 if (addr_3 < the_end) {
768 HeapWord* b_start_3 = block_start_const(addr_3);
769 if (b_start_3 != p) {
770 log_error(gc, verify)("BOT look up for top + diff: " PTR_FORMAT " "
771 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
772 p2i(addr_3), p2i(b_start_3), p2i(p));
773 *failures = true;
774 return;
775 }
776 }
777
778 // Look up end - 1
779 HeapWord* addr_4 = the_end - 1;
780 HeapWord* b_start_4 = block_start_const(addr_4);
781 if (b_start_4 != p) {
782 log_error(gc, verify)("BOT look up for end - 1: " PTR_FORMAT " "
783 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
784 p2i(addr_4), p2i(b_start_4), p2i(p));
785 *failures = true;
786 return;
787 }
788 }
789
790 verify_strong_code_roots(vo, failures);
791 }
792
793 void HeapRegion::verify() const {
794 bool dummy = false;
795 verify(VerifyOption_G1UsePrevMarking, /* failures */ &dummy);
796 }
797
798 void HeapRegion::verify_rem_set(VerifyOption vo, bool* failures) const {
799 G1CollectedHeap* g1h = G1CollectedHeap::heap();
800 *failures = false;
801 HeapWord* p = bottom();
802 HeapWord* prev_p = NULL;
803 VerifyRemSetClosure vr_cl(g1h, vo);
804 while (p < top()) {
805 oop obj = cast_to_oop(p);
806 size_t obj_size = block_size(p);
807
808 if (!g1h->is_obj_dead_cond(obj, this, vo)) {
809 if (oopDesc::is_oop(obj)) {
810 vr_cl.set_containing_obj(obj);
811 obj->oop_iterate(&vr_cl);
812
813 if (vr_cl.failures()) {
814 *failures = true;
815 }
816 if (G1MaxVerifyFailures >= 0 &&
817 vr_cl.n_failures() >= G1MaxVerifyFailures) {
818 return;
819 }
820 } else {
821 log_error(gc, verify)(PTR_FORMAT " not an oop", p2i(obj));
822 *failures = true;
823 return;
824 }
825 }
826
827 prev_p = p;
828 p += obj_size;
829 }
830 }
831
832 void HeapRegion::verify_rem_set() const {
833 bool failures = false;
834 verify_rem_set(VerifyOption_G1UsePrevMarking, &failures);
835 guarantee(!failures, "HeapRegion RemSet verification failed");
836 }
837
838 void HeapRegion::clear(bool mangle_space) {
839 set_top(bottom());
840 set_compaction_top(bottom());
841
842 if (ZapUnusedHeapArea && mangle_space) {
843 mangle_unused_area();
844 }
845 reset_bot();
846 }
847
848 #ifndef PRODUCT
849 void HeapRegion::mangle_unused_area() {
850 SpaceMangler::mangle_region(MemRegion(top(), end()));
851 }
852 #endif
853
854 HeapWord* HeapRegion::initialize_threshold() {
855 return _bot_part.initialize_threshold();
856 }
857
858 HeapWord* HeapRegion::cross_threshold(HeapWord* start, HeapWord* end) {
859 _bot_part.alloc_block(start, end);
860 return _bot_part.threshold();
861 }
862
863 template<bool RESOLVE>
864 void HeapRegion::object_iterate_impl(ObjectClosure* blk) {
865 HeapWord* p = bottom();
866 while (p < top()) {
867 if (block_is_obj(p)) {
868 blk->do_object(cast_to_oop(p));
869 }
870 p += block_size<RESOLVE>(p);
871 }
872 }
873
874 void HeapRegion::object_iterate(ObjectClosure* blk) {
875 if (!UseCompactObjectHeaders || G1CollectedHeap::heap()->collector_state()->in_full_gc()) {
876 object_iterate_impl<false>(blk);
877 } else {
878 object_iterate_impl<true>(blk);
879 }
880 }