1 /*
2 * Copyright (c) 2001, 2018, 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/g1BlockOffsetTable.inline.hpp"
28 #include "gc/g1/g1CollectedHeap.inline.hpp"
29 #include "gc/g1/g1HeapRegionTraceType.hpp"
30 #include "gc/g1/g1OopClosures.inline.hpp"
31 #include "gc/g1/heapRegion.inline.hpp"
32 #include "gc/g1/heapRegionBounds.inline.hpp"
33 #include "gc/g1/heapRegionManager.inline.hpp"
34 #include "gc/g1/heapRegionRemSet.hpp"
35 #include "gc/g1/heapRegionTracer.hpp"
36 #include "gc/shared/genOopClosures.inline.hpp"
37 #include "gc/shared/space.inline.hpp"
38 #include "logging/log.hpp"
39 #include "logging/logStream.hpp"
40 #include "memory/iterator.inline.hpp"
41 #include "memory/resourceArea.hpp"
42 #include "oops/access.inline.hpp"
43 #include "oops/compressedOops.inline.hpp"
44 #include "oops/oop.inline.hpp"
45 #include "runtime/atomic.hpp"
46 #include "runtime/orderAccess.hpp"
47 #include "utilities/growableArray.hpp"
48
49 int HeapRegion::LogOfHRGrainBytes = 0;
50 int HeapRegion::LogOfHRGrainWords = 0;
51 size_t HeapRegion::GrainBytes = 0;
52 size_t HeapRegion::GrainWords = 0;
53 size_t HeapRegion::CardsPerRegion = 0;
54
55 size_t HeapRegion::max_region_size() {
56 return HeapRegionBounds::max_size();
57 }
58
59 size_t HeapRegion::min_region_size_in_words() {
60 return HeapRegionBounds::min_size() >> LogHeapWordSize;
61 }
62
63 void HeapRegion::setup_heap_region_size(size_t initial_heap_size, size_t max_heap_size) {
64 size_t region_size = G1HeapRegionSize;
65 if (FLAG_IS_DEFAULT(G1HeapRegionSize)) {
66 size_t average_heap_size = (initial_heap_size + max_heap_size) / 2;
67 region_size = MAX2(average_heap_size / HeapRegionBounds::target_number(),
68 HeapRegionBounds::min_size());
69 }
70
71 int region_size_log = log2_long((jlong) region_size);
72 // Recalculate the region size to make sure it's a power of
73 // 2. This means that region_size is the largest power of 2 that's
74 // <= what we've calculated so far.
75 region_size = ((size_t)1 << region_size_log);
76
77 // Now make sure that we don't go over or under our limits.
78 if (region_size < HeapRegionBounds::min_size()) {
79 region_size = HeapRegionBounds::min_size();
80 } else if (region_size > HeapRegionBounds::max_size()) {
81 region_size = HeapRegionBounds::max_size();
82 }
83
84 // And recalculate the log.
85 region_size_log = log2_long((jlong) region_size);
86
87 // Now, set up the globals.
88 guarantee(LogOfHRGrainBytes == 0, "we should only set it once");
89 LogOfHRGrainBytes = region_size_log;
90
91 guarantee(LogOfHRGrainWords == 0, "we should only set it once");
92 LogOfHRGrainWords = LogOfHRGrainBytes - LogHeapWordSize;
93
94 guarantee(GrainBytes == 0, "we should only set it once");
95 // The cast to int is safe, given that we've bounded region_size by
96 // MIN_REGION_SIZE and MAX_REGION_SIZE.
97 GrainBytes = region_size;
98 log_info(gc, heap)("Heap region size: " SIZE_FORMAT "M", GrainBytes / M);
99
100 guarantee(GrainWords == 0, "we should only set it once");
101 GrainWords = GrainBytes >> LogHeapWordSize;
102 guarantee((size_t) 1 << LogOfHRGrainWords == GrainWords, "sanity");
103
104 guarantee(CardsPerRegion == 0, "we should only set it once");
105 CardsPerRegion = GrainBytes >> G1CardTable::card_shift;
106
107 if (G1HeapRegionSize != GrainBytes) {
108 FLAG_SET_ERGO(size_t, G1HeapRegionSize, GrainBytes);
109 }
110 }
111
112 void HeapRegion::hr_clear(bool keep_remset, bool clear_space, bool locked) {
113 assert(_humongous_start_region == NULL,
114 "we should have already filtered out humongous regions");
115 assert(!in_collection_set(),
116 "Should not clear heap region %u in the collection set", hrm_index());
117
118 set_young_index_in_cset(-1);
119 uninstall_surv_rate_group();
120 set_free();
121 reset_pre_dummy_top();
122
123 if (!keep_remset) {
124 if (locked) {
125 rem_set()->clear_locked();
126 } else {
127 rem_set()->clear();
128 }
129 }
130
131 zero_marked_bytes();
132
133 init_top_at_mark_start();
134 if (clear_space) clear(SpaceDecorator::Mangle);
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 G1CollectedHeap* g1h = G1CollectedHeap::heap();
146 G1Policy* g1p = g1h->g1_policy();
147
148 // Retrieve a prediction of the elapsed time for this region for
149 // a mixed gc because the region will only be evacuated during a
150 // mixed gc.
151 double region_elapsed_time_ms =
152 g1p->predict_region_elapsed_time_ms(this, false /* for_young_gc */);
153 _gc_efficiency = (double) reclaimable_bytes() / region_elapsed_time_ms;
154 }
155
156 void HeapRegion::set_free() {
157 report_region_type_change(G1HeapRegionTraceType::Free);
158 _type.set_free();
159 }
160
161 void HeapRegion::set_eden() {
162 report_region_type_change(G1HeapRegionTraceType::Eden);
163 _type.set_eden();
164 }
165
166 void HeapRegion::set_eden_pre_gc() {
167 report_region_type_change(G1HeapRegionTraceType::Eden);
168 _type.set_eden_pre_gc();
169 }
170
171 void HeapRegion::set_survivor() {
172 report_region_type_change(G1HeapRegionTraceType::Survivor);
173 _type.set_survivor();
174 }
175
176 void HeapRegion::move_to_old() {
177 if (_type.relabel_as_old()) {
178 report_region_type_change(G1HeapRegionTraceType::Old);
179 }
180 }
181
182 void HeapRegion::set_old() {
183 report_region_type_change(G1HeapRegionTraceType::Old);
184 _type.set_old();
185 }
186
187 void HeapRegion::set_premature_old() {
188 report_region_type_change(G1HeapRegionTraceType::Old);
189 _type.set_premature_old();
190 }
191
192 void HeapRegion::set_open_archive() {
193 report_region_type_change(G1HeapRegionTraceType::OpenArchive);
194 _type.set_open_archive();
195 }
196
197 void HeapRegion::set_closed_archive() {
198 report_region_type_change(G1HeapRegionTraceType::ClosedArchive);
199 _type.set_closed_archive();
200 }
201
202 void HeapRegion::set_starts_humongous(HeapWord* obj_top, size_t fill_size) {
203 assert(!is_humongous(), "sanity / pre-condition");
204 assert(top() == bottom(), "should be empty");
205
206 report_region_type_change(G1HeapRegionTraceType::StartsHumongous);
207 _type.set_starts_humongous();
208 _humongous_start_region = this;
209
210 _bot_part.set_for_starts_humongous(obj_top, fill_size);
211 }
212
213 void HeapRegion::set_continues_humongous(HeapRegion* first_hr) {
214 assert(!is_humongous(), "sanity / pre-condition");
215 assert(top() == bottom(), "should be empty");
216 assert(first_hr->is_starts_humongous(), "pre-condition");
217
218 report_region_type_change(G1HeapRegionTraceType::ContinuesHumongous);
219 _type.set_continues_humongous();
220 _humongous_start_region = first_hr;
221
222 _bot_part.set_object_can_span(true);
223 }
224
225 void HeapRegion::clear_humongous() {
226 assert(is_humongous(), "pre-condition");
227
228 assert(capacity() == HeapRegion::GrainBytes, "pre-condition");
229 _humongous_start_region = NULL;
230
231 _bot_part.set_object_can_span(false);
232 }
233
234 HeapRegion::HeapRegion(uint hrm_index,
235 G1BlockOffsetTable* bot,
236 MemRegion mr) :
237 G1ContiguousSpace(bot),
238 _rem_set(NULL),
239 _hrm_index(hrm_index),
240 _type(),
241 _humongous_start_region(NULL),
242 _evacuation_failed(false),
243 _next(NULL), _prev(NULL),
244 #ifdef ASSERT
245 _containing_set(NULL),
246 #endif
247 _prev_marked_bytes(0), _next_marked_bytes(0), _gc_efficiency(0.0),
248 _young_index_in_cset(-1), _surv_rate_group(NULL), _age_index(-1),
249 _prev_top_at_mark_start(NULL), _next_top_at_mark_start(NULL),
250 _recorded_rs_length(0), _predicted_elapsed_time_ms(0)
251 {
252 _rem_set = new HeapRegionRemSet(bot, this);
253
254 initialize(mr);
255 }
256
257 void HeapRegion::initialize(MemRegion mr, bool clear_space, bool mangle_space) {
258 assert(_rem_set->is_empty(), "Remembered set must be empty");
259
260 G1ContiguousSpace::initialize(mr, clear_space, mangle_space);
261
262 hr_clear(false /*par*/, false /*clear_space*/);
263 set_top(bottom());
264 }
265
266 void HeapRegion::report_region_type_change(G1HeapRegionTraceType::Type to) {
267 HeapRegionTracer::send_region_type_change(_hrm_index,
268 get_trace_type(),
269 to,
270 (uintptr_t)bottom(),
271 used());
272 }
273
274 void HeapRegion::note_self_forwarding_removal_start(bool during_initial_mark,
275 bool during_conc_mark) {
276 // We always recreate the prev marking info and we'll explicitly
277 // mark all objects we find to be self-forwarded on the prev
278 // bitmap. So all objects need to be below PTAMS.
279 _prev_marked_bytes = 0;
280
281 if (during_initial_mark) {
282 // During initial-mark, we'll also explicitly mark all objects
283 // we find to be self-forwarded on the next bitmap. So all
284 // objects need to be below NTAMS.
285 _next_top_at_mark_start = top();
286 _next_marked_bytes = 0;
287 } else if (during_conc_mark) {
288 // During concurrent mark, all objects in the CSet (including
289 // the ones we find to be self-forwarded) are implicitly live.
290 // So all objects need to be above NTAMS.
291 _next_top_at_mark_start = bottom();
292 _next_marked_bytes = 0;
293 }
294 }
295
296 void HeapRegion::note_self_forwarding_removal_end(size_t marked_bytes) {
297 assert(marked_bytes <= used(),
298 "marked: " SIZE_FORMAT " used: " SIZE_FORMAT, marked_bytes, used());
299 _prev_top_at_mark_start = top();
300 _prev_marked_bytes = marked_bytes;
301 }
302
303 // Code roots support
304
305 void HeapRegion::add_strong_code_root(nmethod* nm) {
306 HeapRegionRemSet* hrrs = rem_set();
307 hrrs->add_strong_code_root(nm);
308 }
309
310 void HeapRegion::add_strong_code_root_locked(nmethod* nm) {
311 assert_locked_or_safepoint(CodeCache_lock);
312 HeapRegionRemSet* hrrs = rem_set();
313 hrrs->add_strong_code_root_locked(nm);
314 }
315
316 void HeapRegion::remove_strong_code_root(nmethod* nm) {
317 HeapRegionRemSet* hrrs = rem_set();
318 hrrs->remove_strong_code_root(nm);
319 }
320
321 void HeapRegion::strong_code_roots_do(CodeBlobClosure* blk) const {
322 HeapRegionRemSet* hrrs = rem_set();
323 hrrs->strong_code_roots_do(blk);
324 }
325
326 class VerifyStrongCodeRootOopClosure: public OopClosure {
327 const HeapRegion* _hr;
328 bool _failures;
329 bool _has_oops_in_region;
330
331 template <class T> void do_oop_work(T* p) {
332 T heap_oop = RawAccess<>::oop_load(p);
333 if (!CompressedOops::is_null(heap_oop)) {
334 oop obj = CompressedOops::decode_not_null(heap_oop);
335
336 // Note: not all the oops embedded in the nmethod are in the
337 // current region. We only look at those which are.
338 if (_hr->is_in(obj)) {
339 // Object is in the region. Check that its less than top
340 if (_hr->top() <= (HeapWord*)obj) {
341 // Object is above top
342 log_error(gc, verify)("Object " PTR_FORMAT " in region [" PTR_FORMAT ", " PTR_FORMAT ") is above top " PTR_FORMAT,
343 p2i(obj), p2i(_hr->bottom()), p2i(_hr->end()), p2i(_hr->top()));
344 _failures = true;
345 return;
346 }
347 // Nmethod has at least one oop in the current region
348 _has_oops_in_region = true;
349 }
350 }
351 }
352
353 public:
354 VerifyStrongCodeRootOopClosure(const HeapRegion* hr):
355 _hr(hr), _failures(false), _has_oops_in_region(false) {}
356
357 void do_oop(narrowOop* p) { do_oop_work(p); }
358 void do_oop(oop* p) { do_oop_work(p); }
359
360 bool failures() { return _failures; }
361 bool has_oops_in_region() { return _has_oops_in_region; }
362 };
363
364 class VerifyStrongCodeRootCodeBlobClosure: public CodeBlobClosure {
365 const HeapRegion* _hr;
366 bool _failures;
367 public:
368 VerifyStrongCodeRootCodeBlobClosure(const HeapRegion* hr) :
369 _hr(hr), _failures(false) {}
370
371 void do_code_blob(CodeBlob* cb) {
372 nmethod* nm = (cb == NULL) ? NULL : cb->as_compiled_method()->as_nmethod_or_null();
373 if (nm != NULL) {
374 // Verify that the nemthod is live
375 if (!nm->is_alive()) {
376 log_error(gc, verify)("region [" PTR_FORMAT "," PTR_FORMAT "] has dead nmethod " PTR_FORMAT " in its strong code roots",
377 p2i(_hr->bottom()), p2i(_hr->end()), p2i(nm));
378 _failures = true;
379 } else {
380 VerifyStrongCodeRootOopClosure oop_cl(_hr);
381 nm->oops_do(&oop_cl);
382 if (!oop_cl.has_oops_in_region()) {
383 log_error(gc, verify)("region [" PTR_FORMAT "," PTR_FORMAT "] has nmethod " PTR_FORMAT " in its strong code roots with no pointers into region",
384 p2i(_hr->bottom()), p2i(_hr->end()), p2i(nm));
385 _failures = true;
386 } else if (oop_cl.failures()) {
387 log_error(gc, verify)("region [" PTR_FORMAT "," PTR_FORMAT "] has other failures for nmethod " PTR_FORMAT,
388 p2i(_hr->bottom()), p2i(_hr->end()), p2i(nm));
389 _failures = true;
390 }
391 }
392 }
393 }
394
395 bool failures() { return _failures; }
396 };
397
398 void HeapRegion::verify_strong_code_roots(VerifyOption vo, bool* failures) const {
399 if (!G1VerifyHeapRegionCodeRoots) {
400 // We're not verifying code roots.
401 return;
402 }
403 if (vo == VerifyOption_G1UseFullMarking) {
404 // Marking verification during a full GC is performed after class
405 // unloading, code cache unloading, etc so the strong code roots
406 // attached to each heap region are in an inconsistent state. They won't
407 // be consistent until the strong code roots are rebuilt after the
408 // actual GC. Skip verifying the strong code roots in this particular
409 // time.
410 assert(VerifyDuringGC, "only way to get here");
411 return;
412 }
413
414 HeapRegionRemSet* hrrs = rem_set();
415 size_t strong_code_roots_length = hrrs->strong_code_roots_list_length();
416
417 // if this region is empty then there should be no entries
418 // on its strong code root list
419 if (is_empty()) {
420 if (strong_code_roots_length > 0) {
421 log_error(gc, verify)("region [" PTR_FORMAT "," PTR_FORMAT "] is empty but has " SIZE_FORMAT " code root entries",
422 p2i(bottom()), p2i(end()), strong_code_roots_length);
423 *failures = true;
424 }
425 return;
426 }
427
428 if (is_continues_humongous()) {
429 if (strong_code_roots_length > 0) {
430 log_error(gc, verify)("region " HR_FORMAT " is a continuation of a humongous region but has " SIZE_FORMAT " code root entries",
431 HR_FORMAT_PARAMS(this), strong_code_roots_length);
432 *failures = true;
433 }
434 return;
435 }
436
437 VerifyStrongCodeRootCodeBlobClosure cb_cl(this);
438 strong_code_roots_do(&cb_cl);
439
440 if (cb_cl.failures()) {
441 *failures = true;
442 }
443 }
444
445 void HeapRegion::print() const { print_on(tty); }
446 void HeapRegion::print_on(outputStream* st) const {
447 st->print("|%4u", this->_hrm_index);
448 st->print("|" PTR_FORMAT ", " PTR_FORMAT ", " PTR_FORMAT,
449 p2i(bottom()), p2i(top()), p2i(end()));
450 st->print("|%3d%%", (int) ((double) used() * 100 / capacity()));
451 st->print("|%2s", get_short_type_str());
452 if (in_collection_set()) {
453 st->print("|CS");
454 } else {
455 st->print("| ");
456 }
457 st->print_cr("|TAMS " PTR_FORMAT ", " PTR_FORMAT "| %s ",
458 p2i(prev_top_at_mark_start()), p2i(next_top_at_mark_start()), rem_set()->get_state_str());
459 }
460
461 class G1VerificationClosure : public BasicOopIterateClosure {
462 protected:
463 G1CollectedHeap* _g1h;
464 G1CardTable *_ct;
465 oop _containing_obj;
466 bool _failures;
467 int _n_failures;
468 VerifyOption _vo;
469 public:
470 // _vo == UsePrevMarking -> use "prev" marking information,
471 // _vo == UseNextMarking -> use "next" marking information,
472 // _vo == UseFullMarking -> use "next" marking bitmap but no TAMS.
473 G1VerificationClosure(G1CollectedHeap* g1h, VerifyOption vo) :
474 _g1h(g1h), _ct(g1h->card_table()),
475 _containing_obj(NULL), _failures(false), _n_failures(0), _vo(vo) {
476 }
477
478 void set_containing_obj(oop obj) {
479 _containing_obj = obj;
480 }
481
482 bool failures() { return _failures; }
483 int n_failures() { return _n_failures; }
484
485 void print_object(outputStream* out, oop obj) {
486 #ifdef PRODUCT
487 Klass* k = obj->klass();
488 const char* class_name = k->external_name();
489 out->print_cr("class name %s", class_name);
490 #else // PRODUCT
491 obj->print_on(out);
492 #endif // PRODUCT
493 }
494
495 // This closure provides its own oop verification code.
496 debug_only(virtual bool should_verify_oops() { return false; })
497 };
498
499 class VerifyLiveClosure : public G1VerificationClosure {
500 public:
501 VerifyLiveClosure(G1CollectedHeap* g1h, VerifyOption vo) : G1VerificationClosure(g1h, vo) {}
502 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
503 virtual void do_oop(oop* p) { do_oop_work(p); }
504
505 template <class T>
506 void do_oop_work(T* p) {
507 assert(_containing_obj != NULL, "Precondition");
508 assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo),
509 "Precondition");
510 verify_liveness(p);
511 }
512
513 template <class T>
514 void verify_liveness(T* p) {
515 T heap_oop = RawAccess<>::oop_load(p);
516 Log(gc, verify) log;
517 if (!CompressedOops::is_null(heap_oop)) {
518 oop obj = CompressedOops::decode_not_null(heap_oop);
519 bool failed = false;
520 if (!_g1h->is_in_closed_subset(obj) || _g1h->is_obj_dead_cond(obj, _vo)) {
521 MutexLockerEx x(ParGCRareEvent_lock,
522 Mutex::_no_safepoint_check_flag);
523
524 if (!_failures) {
525 log.error("----------");
526 }
527 ResourceMark rm;
528 if (!_g1h->is_in_closed_subset(obj)) {
529 HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
530 log.error("Field " PTR_FORMAT " of live obj " PTR_FORMAT " in region [" PTR_FORMAT ", " PTR_FORMAT ")",
531 p2i(p), p2i(_containing_obj), p2i(from->bottom()), p2i(from->end()));
532 LogStream ls(log.error());
533 print_object(&ls, _containing_obj);
534 HeapRegion* const to = _g1h->heap_region_containing(obj);
535 log.error("points to obj " PTR_FORMAT " in region " HR_FORMAT " remset %s", p2i(obj), HR_FORMAT_PARAMS(to), to->rem_set()->get_state_str());
536 } else {
537 HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
538 HeapRegion* to = _g1h->heap_region_containing((HeapWord*)obj);
539 log.error("Field " PTR_FORMAT " of live obj " PTR_FORMAT " in region [" PTR_FORMAT ", " PTR_FORMAT ")",
540 p2i(p), p2i(_containing_obj), p2i(from->bottom()), p2i(from->end()));
541 LogStream ls(log.error());
542 print_object(&ls, _containing_obj);
543 log.error("points to dead obj " PTR_FORMAT " in region [" PTR_FORMAT ", " PTR_FORMAT ")",
544 p2i(obj), p2i(to->bottom()), p2i(to->end()));
545 print_object(&ls, obj);
546 }
547 log.error("----------");
548 _failures = true;
549 failed = true;
550 _n_failures++;
551 }
552 }
553 }
554 };
555
556 class VerifyRemSetClosure : public G1VerificationClosure {
557 public:
558 VerifyRemSetClosure(G1CollectedHeap* g1h, VerifyOption vo) : G1VerificationClosure(g1h, vo) {}
559 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
560 virtual void do_oop(oop* p) { do_oop_work(p); }
561
562 template <class T>
563 void do_oop_work(T* p) {
564 assert(_containing_obj != NULL, "Precondition");
565 assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo),
566 "Precondition");
567 verify_remembered_set(p);
568 }
569
570 template <class T>
571 void verify_remembered_set(T* p) {
572 T heap_oop = RawAccess<>::oop_load(p);
573 Log(gc, verify) log;
574 if (!CompressedOops::is_null(heap_oop)) {
575 oop obj = CompressedOops::decode_not_null(heap_oop);
576 HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
577 HeapRegion* to = _g1h->heap_region_containing(obj);
578 if (from != NULL && to != NULL &&
579 from != to &&
580 !to->is_pinned() &&
581 to->rem_set()->is_complete()) {
582 jbyte cv_obj = *_ct->byte_for_const(_containing_obj);
583 jbyte cv_field = *_ct->byte_for_const(p);
584 const jbyte dirty = G1CardTable::dirty_card_val();
585
586 bool is_bad = !(from->is_young()
587 || to->rem_set()->contains_reference(p)
588 || (_containing_obj->is_objArray() ?
589 cv_field == dirty :
590 cv_obj == dirty || cv_field == dirty));
591 if (is_bad) {
592 MutexLockerEx x(ParGCRareEvent_lock,
593 Mutex::_no_safepoint_check_flag);
594
595 if (!_failures) {
596 log.error("----------");
597 }
598 log.error("Missing rem set entry:");
599 log.error("Field " PTR_FORMAT " of obj " PTR_FORMAT ", in region " HR_FORMAT,
600 p2i(p), p2i(_containing_obj), HR_FORMAT_PARAMS(from));
601 ResourceMark rm;
602 LogStream ls(log.error());
603 _containing_obj->print_on(&ls);
604 log.error("points to obj " PTR_FORMAT " in region " HR_FORMAT " remset %s", p2i(obj), HR_FORMAT_PARAMS(to), to->rem_set()->get_state_str());
605 if (oopDesc::is_oop(obj)) {
606 obj->print_on(&ls);
607 }
608 log.error("Obj head CTE = %d, field CTE = %d.", cv_obj, cv_field);
609 log.error("----------");
610 _failures = true;
611 _n_failures++;
612 }
613 }
614 }
615 }
616 };
617
618 // Closure that applies the given two closures in sequence.
619 class G1Mux2Closure : public BasicOopIterateClosure {
620 OopClosure* _c1;
621 OopClosure* _c2;
622 public:
623 G1Mux2Closure(OopClosure *c1, OopClosure *c2) { _c1 = c1; _c2 = c2; }
624 template <class T> inline void do_oop_work(T* p) {
625 // Apply first closure; then apply the second.
626 _c1->do_oop(p);
627 _c2->do_oop(p);
628 }
629 virtual inline void do_oop(oop* p) { do_oop_work(p); }
630 virtual inline void do_oop(narrowOop* p) { do_oop_work(p); }
631
632 // This closure provides its own oop verification code.
633 debug_only(virtual bool should_verify_oops() { return false; })
634 };
635
636 // This really ought to be commoned up into OffsetTableContigSpace somehow.
637 // We would need a mechanism to make that code skip dead objects.
638
639 void HeapRegion::verify(VerifyOption vo,
640 bool* failures) const {
641 G1CollectedHeap* g1h = G1CollectedHeap::heap();
642 *failures = false;
643 HeapWord* p = bottom();
644 HeapWord* prev_p = NULL;
645 VerifyLiveClosure vl_cl(g1h, vo);
646 VerifyRemSetClosure vr_cl(g1h, vo);
647 bool is_region_humongous = is_humongous();
648 size_t object_num = 0;
649 while (p < top()) {
650 oop obj = oop(p);
651 size_t obj_size = block_size(p);
652 object_num += 1;
653
654 if (!g1h->is_obj_dead_cond(obj, this, vo)) {
655 if (oopDesc::is_oop(obj)) {
656 Klass* klass = obj->klass();
657 bool is_metaspace_object = Metaspace::contains(klass);
658 if (!is_metaspace_object) {
659 log_error(gc, verify)("klass " PTR_FORMAT " of object " PTR_FORMAT " "
660 "not metadata", p2i(klass), p2i(obj));
661 *failures = true;
662 return;
663 } else if (!klass->is_klass()) {
664 log_error(gc, verify)("klass " PTR_FORMAT " of object " PTR_FORMAT " "
665 "not a klass", p2i(klass), p2i(obj));
666 *failures = true;
667 return;
668 } else {
669 vl_cl.set_containing_obj(obj);
670 if (!g1h->collector_state()->in_full_gc() || G1VerifyRSetsDuringFullGC) {
671 // verify liveness and rem_set
672 vr_cl.set_containing_obj(obj);
673 G1Mux2Closure mux(&vl_cl, &vr_cl);
674 obj->oop_iterate(&mux);
675
676 if (vr_cl.failures()) {
677 *failures = true;
678 }
679 if (G1MaxVerifyFailures >= 0 &&
680 vr_cl.n_failures() >= G1MaxVerifyFailures) {
681 return;
682 }
683 } else {
684 // verify only liveness
685 obj->oop_iterate(&vl_cl);
686 }
687 if (vl_cl.failures()) {
688 *failures = true;
689 }
690 if (G1MaxVerifyFailures >= 0 &&
691 vl_cl.n_failures() >= G1MaxVerifyFailures) {
692 return;
693 }
694 }
695 } else {
696 log_error(gc, verify)(PTR_FORMAT " not an oop", p2i(obj));
697 *failures = true;
698 return;
699 }
700 }
701 prev_p = p;
702 p += obj_size;
703 }
704
705 if (!is_young() && !is_empty()) {
706 _bot_part.verify();
707 }
708
709 if (is_region_humongous) {
710 oop obj = oop(this->humongous_start_region()->bottom());
711 if ((HeapWord*)obj > bottom() || (HeapWord*)obj + obj->size() < bottom()) {
712 log_error(gc, verify)("this humongous region is not part of its' humongous object " PTR_FORMAT, p2i(obj));
713 *failures = true;
714 return;
715 }
716 }
717
718 if (!is_region_humongous && p != top()) {
719 log_error(gc, verify)("end of last object " PTR_FORMAT " "
720 "does not match top " PTR_FORMAT, p2i(p), p2i(top()));
721 *failures = true;
722 return;
723 }
724
725 HeapWord* the_end = end();
726 // Do some extra BOT consistency checking for addresses in the
727 // range [top, end). BOT look-ups in this range should yield
728 // top. No point in doing that if top == end (there's nothing there).
729 if (p < the_end) {
730 // Look up top
731 HeapWord* addr_1 = p;
732 HeapWord* b_start_1 = _bot_part.block_start_const(addr_1);
733 if (b_start_1 != p) {
734 log_error(gc, verify)("BOT look up for top: " PTR_FORMAT " "
735 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
736 p2i(addr_1), p2i(b_start_1), p2i(p));
737 *failures = true;
738 return;
739 }
740
741 // Look up top + 1
742 HeapWord* addr_2 = p + 1;
743 if (addr_2 < the_end) {
744 HeapWord* b_start_2 = _bot_part.block_start_const(addr_2);
745 if (b_start_2 != p) {
746 log_error(gc, verify)("BOT look up for top + 1: " PTR_FORMAT " "
747 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
748 p2i(addr_2), p2i(b_start_2), p2i(p));
749 *failures = true;
750 return;
751 }
752 }
753
754 // Look up an address between top and end
755 size_t diff = pointer_delta(the_end, p) / 2;
756 HeapWord* addr_3 = p + diff;
757 if (addr_3 < the_end) {
758 HeapWord* b_start_3 = _bot_part.block_start_const(addr_3);
759 if (b_start_3 != p) {
760 log_error(gc, verify)("BOT look up for top + diff: " PTR_FORMAT " "
761 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
762 p2i(addr_3), p2i(b_start_3), p2i(p));
763 *failures = true;
764 return;
765 }
766 }
767
768 // Look up end - 1
769 HeapWord* addr_4 = the_end - 1;
770 HeapWord* b_start_4 = _bot_part.block_start_const(addr_4);
771 if (b_start_4 != p) {
772 log_error(gc, verify)("BOT look up for end - 1: " PTR_FORMAT " "
773 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
774 p2i(addr_4), p2i(b_start_4), p2i(p));
775 *failures = true;
776 return;
777 }
778 }
779
780 verify_strong_code_roots(vo, failures);
781 }
782
783 void HeapRegion::verify() const {
784 bool dummy = false;
785 verify(VerifyOption_G1UsePrevMarking, /* failures */ &dummy);
786 }
787
788 void HeapRegion::verify_rem_set(VerifyOption vo, bool* failures) const {
789 G1CollectedHeap* g1h = G1CollectedHeap::heap();
790 *failures = false;
791 HeapWord* p = bottom();
792 HeapWord* prev_p = NULL;
793 VerifyRemSetClosure vr_cl(g1h, vo);
794 while (p < top()) {
795 oop obj = oop(p);
796 size_t obj_size = block_size(p);
797
798 if (!g1h->is_obj_dead_cond(obj, this, vo)) {
799 if (oopDesc::is_oop(obj)) {
800 vr_cl.set_containing_obj(obj);
801 obj->oop_iterate(&vr_cl);
802
803 if (vr_cl.failures()) {
804 *failures = true;
805 }
806 if (G1MaxVerifyFailures >= 0 &&
807 vr_cl.n_failures() >= G1MaxVerifyFailures) {
808 return;
809 }
810 } else {
811 log_error(gc, verify)(PTR_FORMAT " not an oop", p2i(obj));
812 *failures = true;
813 return;
814 }
815 }
816
817 prev_p = p;
818 p += obj_size;
819 }
820 }
821
822 void HeapRegion::verify_rem_set() const {
823 bool failures = false;
824 verify_rem_set(VerifyOption_G1UsePrevMarking, &failures);
825 guarantee(!failures, "HeapRegion RemSet verification failed");
826 }
827
828 void HeapRegion::prepare_for_compaction(CompactPoint* cp) {
829 // Not used for G1 anymore, but pure virtual in Space.
830 ShouldNotReachHere();
831 }
832
833 // G1OffsetTableContigSpace code; copied from space.cpp. Hope this can go
834 // away eventually.
835
836 void G1ContiguousSpace::clear(bool mangle_space) {
837 set_top(bottom());
838 CompactibleSpace::clear(mangle_space);
839 reset_bot();
840 }
841 #ifndef PRODUCT
842 void G1ContiguousSpace::mangle_unused_area() {
843 mangle_unused_area_complete();
844 }
845
846 void G1ContiguousSpace::mangle_unused_area_complete() {
847 SpaceMangler::mangle_region(MemRegion(top(), end()));
848 }
849 #endif
850
851 void G1ContiguousSpace::print() const {
852 print_short();
853 tty->print_cr(" [" INTPTR_FORMAT ", " INTPTR_FORMAT ", "
854 INTPTR_FORMAT ", " INTPTR_FORMAT ")",
855 p2i(bottom()), p2i(top()), p2i(_bot_part.threshold()), p2i(end()));
856 }
857
858 HeapWord* G1ContiguousSpace::initialize_threshold() {
859 return _bot_part.initialize_threshold();
860 }
861
862 HeapWord* G1ContiguousSpace::cross_threshold(HeapWord* start,
863 HeapWord* end) {
864 _bot_part.alloc_block(start, end);
865 return _bot_part.threshold();
866 }
867
868 void G1ContiguousSpace::safe_object_iterate(ObjectClosure* blk) {
869 object_iterate(blk);
870 }
871
872 void G1ContiguousSpace::object_iterate(ObjectClosure* blk) {
873 HeapWord* p = bottom();
874 while (p < top()) {
875 if (block_is_obj(p)) {
876 blk->do_object(oop(p));
877 }
878 p += block_size(p);
879 }
880 }
881
882 G1ContiguousSpace::G1ContiguousSpace(G1BlockOffsetTable* bot) :
883 _bot_part(bot, this),
884 _par_alloc_lock(Mutex::leaf, "OffsetTableContigSpace par alloc lock", true)
885 {
886 }
887
888 void G1ContiguousSpace::initialize(MemRegion mr, bool clear_space, bool mangle_space) {
889 CompactibleSpace::initialize(mr, clear_space, mangle_space);
890 _top = bottom();
891 set_saved_mark_word(NULL);
892 reset_bot();
893 }