1 /*
2 * Copyright (c) 2001, 2017, 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.hpp"
41 #include "memory/resourceArea.hpp"
42 #include "oops/oop.inline.hpp"
43 #include "runtime/atomic.hpp"
44 #include "runtime/orderAccess.inline.hpp"
45
46 int HeapRegion::LogOfHRGrainBytes = 0;
47 int HeapRegion::LogOfHRGrainWords = 0;
48 size_t HeapRegion::GrainBytes = 0;
49 size_t HeapRegion::GrainWords = 0;
50 size_t HeapRegion::CardsPerRegion = 0;
51
52 size_t HeapRegion::max_region_size() {
53 return HeapRegionBounds::max_size();
54 }
55
56 size_t HeapRegion::min_region_size_in_words() {
57 return HeapRegionBounds::min_size() >> LogHeapWordSize;
58 }
59
60 void HeapRegion::setup_heap_region_size(size_t initial_heap_size, size_t max_heap_size) {
61 size_t region_size = G1HeapRegionSize;
62 if (FLAG_IS_DEFAULT(G1HeapRegionSize)) {
63 size_t average_heap_size = (initial_heap_size + max_heap_size) / 2;
64 region_size = MAX2(average_heap_size / HeapRegionBounds::target_number(),
65 HeapRegionBounds::min_size());
66 }
67
68 int region_size_log = log2_long((jlong) region_size);
69 // Recalculate the region size to make sure it's a power of
70 // 2. This means that region_size is the largest power of 2 that's
71 // <= what we've calculated so far.
72 region_size = ((size_t)1 << region_size_log);
73
74 // Now make sure that we don't go over or under our limits.
75 if (region_size < HeapRegionBounds::min_size()) {
76 region_size = HeapRegionBounds::min_size();
77 } else if (region_size > HeapRegionBounds::max_size()) {
78 region_size = HeapRegionBounds::max_size();
79 }
80
81 // And recalculate the log.
82 region_size_log = log2_long((jlong) region_size);
83
84 // Now, set up the globals.
85 guarantee(LogOfHRGrainBytes == 0, "we should only set it once");
86 LogOfHRGrainBytes = region_size_log;
87
88 guarantee(LogOfHRGrainWords == 0, "we should only set it once");
89 LogOfHRGrainWords = LogOfHRGrainBytes - LogHeapWordSize;
90
91 guarantee(GrainBytes == 0, "we should only set it once");
92 // The cast to int is safe, given that we've bounded region_size by
93 // MIN_REGION_SIZE and MAX_REGION_SIZE.
94 GrainBytes = region_size;
95 log_info(gc, heap)("Heap region size: " SIZE_FORMAT "M", GrainBytes / M);
96
97 guarantee(GrainWords == 0, "we should only set it once");
98 GrainWords = GrainBytes >> LogHeapWordSize;
99 guarantee((size_t) 1 << LogOfHRGrainWords == GrainWords, "sanity");
100
101 guarantee(CardsPerRegion == 0, "we should only set it once");
102 CardsPerRegion = GrainBytes >> CardTableModRefBS::card_shift;
103
104 if (G1HeapRegionSize != GrainBytes) {
105 FLAG_SET_ERGO(size_t, G1HeapRegionSize, GrainBytes);
106 }
107 }
108
109 void HeapRegion::reset_after_compaction() {
110 G1ContiguousSpace::reset_after_compaction();
111 // After a compaction the mark bitmap is invalid, so we must
112 // treat all objects as being inside the unmarked area.
113 zero_marked_bytes();
114 init_top_at_mark_start();
115 }
116
117 void HeapRegion::hr_clear(bool keep_remset, bool clear_space, bool locked) {
118 assert(_humongous_start_region == NULL,
119 "we should have already filtered out humongous regions");
120 assert(!in_collection_set(),
121 "Should not clear heap region %u in the collection set", hrm_index());
122
123 set_allocation_context(AllocationContext::system());
124 set_young_index_in_cset(-1);
125 uninstall_surv_rate_group();
126 set_free();
127 reset_pre_dummy_top();
128
129 if (!keep_remset) {
130 if (locked) {
131 rem_set()->clear_locked();
132 } else {
133 rem_set()->clear();
134 }
135 }
136
137 zero_marked_bytes();
138
139 init_top_at_mark_start();
140 _gc_time_stamp = G1CollectedHeap::heap()->get_gc_time_stamp();
141 if (clear_space) clear(SpaceDecorator::Mangle);
142 }
143
144 void HeapRegion::par_clear() {
145 assert(used() == 0, "the region should have been already cleared");
146 assert(capacity() == HeapRegion::GrainBytes, "should be back to normal");
147 HeapRegionRemSet* hrrs = rem_set();
148 hrrs->clear();
149 CardTableModRefBS* ct_bs =
150 barrier_set_cast<CardTableModRefBS>(G1CollectedHeap::heap()->barrier_set());
151 ct_bs->clear(MemRegion(bottom(), end()));
152 }
153
154 void HeapRegion::calc_gc_efficiency() {
155 // GC efficiency is the ratio of how much space would be
156 // reclaimed over how long we predict it would take to reclaim it.
157 G1CollectedHeap* g1h = G1CollectedHeap::heap();
158 G1Policy* g1p = g1h->g1_policy();
159
160 // Retrieve a prediction of the elapsed time for this region for
161 // a mixed gc because the region will only be evacuated during a
162 // mixed gc.
163 double region_elapsed_time_ms =
164 g1p->predict_region_elapsed_time_ms(this, false /* for_young_gc */);
165 _gc_efficiency = (double) reclaimable_bytes() / region_elapsed_time_ms;
166 }
167
168 void HeapRegion::set_free() {
169 report_region_type_change(G1HeapRegionTraceType::Free);
170 _type.set_free();
171 }
172
173 void HeapRegion::set_eden() {
174 report_region_type_change(G1HeapRegionTraceType::Eden);
175 _type.set_eden();
176 }
177
178 void HeapRegion::set_eden_pre_gc() {
179 report_region_type_change(G1HeapRegionTraceType::Eden);
180 _type.set_eden_pre_gc();
181 }
182
183 void HeapRegion::set_survivor() {
184 report_region_type_change(G1HeapRegionTraceType::Survivor);
185 _type.set_survivor();
186 }
187
188 void HeapRegion::set_old() {
189 report_region_type_change(G1HeapRegionTraceType::Old);
190 _type.set_old();
191 }
192
193 void HeapRegion::set_archive() {
194 report_region_type_change(G1HeapRegionTraceType::Archive);
195 _type.set_archive();
196 }
197
198 void HeapRegion::set_starts_humongous(HeapWord* obj_top, size_t fill_size) {
199 assert(!is_humongous(), "sanity / pre-condition");
200 assert(top() == bottom(), "should be empty");
201
202 report_region_type_change(G1HeapRegionTraceType::StartsHumongous);
203 _type.set_starts_humongous();
204 _humongous_start_region = this;
205
206 _bot_part.set_for_starts_humongous(obj_top, fill_size);
207 }
208
209 void HeapRegion::set_continues_humongous(HeapRegion* first_hr) {
210 assert(!is_humongous(), "sanity / pre-condition");
211 assert(top() == bottom(), "should be empty");
212 assert(first_hr->is_starts_humongous(), "pre-condition");
213
214 report_region_type_change(G1HeapRegionTraceType::ContinuesHumongous);
215 _type.set_continues_humongous();
216 _humongous_start_region = first_hr;
217
218 _bot_part.set_object_can_span(true);
219 }
220
221 void HeapRegion::clear_humongous() {
222 assert(is_humongous(), "pre-condition");
223
224 assert(capacity() == HeapRegion::GrainBytes, "pre-condition");
225 _humongous_start_region = NULL;
226
227 _bot_part.set_object_can_span(false);
228 }
229
230 HeapRegion::HeapRegion(uint hrm_index,
231 G1BlockOffsetTable* bot,
232 MemRegion mr) :
233 G1ContiguousSpace(bot),
234 _hrm_index(hrm_index),
235 _allocation_context(AllocationContext::system()),
236 _humongous_start_region(NULL),
237 _evacuation_failed(false),
238 _prev_marked_bytes(0), _next_marked_bytes(0), _gc_efficiency(0.0),
239 _next(NULL), _prev(NULL),
240 #ifdef ASSERT
241 _containing_set(NULL),
242 #endif // ASSERT
243 _young_index_in_cset(-1), _surv_rate_group(NULL), _age_index(-1),
244 _rem_set(NULL), _recorded_rs_length(0), _predicted_elapsed_time_ms(0)
245 {
246 _rem_set = new HeapRegionRemSet(bot, this);
247
248 initialize(mr);
249 }
250
251 void HeapRegion::initialize(MemRegion mr, bool clear_space, bool mangle_space) {
252 assert(_rem_set->is_empty(), "Remembered set must be empty");
253
254 G1ContiguousSpace::initialize(mr, clear_space, mangle_space);
255
256 hr_clear(false /*par*/, false /*clear_space*/);
257 set_top(bottom());
258 record_timestamp();
259 }
260
261 void HeapRegion::report_region_type_change(G1HeapRegionTraceType::Type to) {
262 HeapRegionTracer::send_region_type_change(_hrm_index,
263 get_trace_type(),
264 to,
265 (uintptr_t)bottom(),
266 used(),
267 (uint)allocation_context());
268 }
269
270 CompactibleSpace* HeapRegion::next_compaction_space() const {
271 return G1CollectedHeap::heap()->next_compaction_region(this);
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 = oopDesc::load_heap_oop(p);
333 if (!oopDesc::is_null(heap_oop)) {
334 oop obj = oopDesc::decode_heap_oop_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_G1UseMarkWord) {
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("|TS%3u", _gc_time_stamp);
458 st->print("|AC%3u", allocation_context());
459 st->print_cr("|TAMS " PTR_FORMAT ", " PTR_FORMAT "|",
460 p2i(prev_top_at_mark_start()), p2i(next_top_at_mark_start()));
461 }
462
463 class G1VerificationClosure : public OopClosure {
464 protected:
465 G1CollectedHeap* _g1h;
466 CardTableModRefBS* _bs;
467 oop _containing_obj;
468 bool _failures;
469 int _n_failures;
470 VerifyOption _vo;
471 public:
472 // _vo == UsePrevMarking -> use "prev" marking information,
473 // _vo == UseNextMarking -> use "next" marking information,
474 // _vo == UseMarkWord -> use mark word from object header.
475 G1VerificationClosure(G1CollectedHeap* g1h, VerifyOption vo) :
476 _g1h(g1h), _bs(barrier_set_cast<CardTableModRefBS>(g1h->barrier_set())),
477 _containing_obj(NULL), _failures(false), _n_failures(0), _vo(vo) {
478 }
479
480 void set_containing_obj(oop obj) {
481 _containing_obj = obj;
482 }
483
484 bool failures() { return _failures; }
485 int n_failures() { return _n_failures; }
486
487 void print_object(outputStream* out, oop obj) {
488 #ifdef PRODUCT
489 Klass* k = obj->klass();
490 const char* class_name = k->external_name();
491 out->print_cr("class name %s", class_name);
492 #else // PRODUCT
493 obj->print_on(out);
494 #endif // PRODUCT
495 }
496 };
497
498 class VerifyLiveClosure : public G1VerificationClosure {
499 public:
500 VerifyLiveClosure(G1CollectedHeap* g1h, VerifyOption vo) : G1VerificationClosure(g1h, vo) {}
501 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
502 virtual void do_oop(oop* p) { do_oop_work(p); }
503
504 template <class T>
505 void do_oop_work(T* p) {
506 assert(_containing_obj != NULL, "Precondition");
507 assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo),
508 "Precondition");
509 verify_liveness(p);
510 }
511
512 template <class T>
513 void verify_liveness(T* p) {
514 T heap_oop = oopDesc::load_heap_oop(p);
515 Log(gc, verify) log;
516 if (!oopDesc::is_null(heap_oop)) {
517 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
518 bool failed = false;
519 if (!_g1h->is_in_closed_subset(obj) || _g1h->is_obj_dead_cond(obj, _vo)) {
520 MutexLockerEx x(ParGCRareEvent_lock,
521 Mutex::_no_safepoint_check_flag);
522
523 if (!_failures) {
524 log.error("----------");
525 }
526 ResourceMark rm;
527 if (!_g1h->is_in_closed_subset(obj)) {
528 HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
529 log.error("Field " PTR_FORMAT " of live obj " PTR_FORMAT " in region [" PTR_FORMAT ", " PTR_FORMAT ")",
530 p2i(p), p2i(_containing_obj), p2i(from->bottom()), p2i(from->end()));
531 LogStream ls(log.error());
532 print_object(&ls, _containing_obj);
533 log.error("points to obj " PTR_FORMAT " not in the heap", p2i(obj));
534 } else {
535 HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
536 HeapRegion* to = _g1h->heap_region_containing((HeapWord*)obj);
537 log.error("Field " PTR_FORMAT " of live obj " PTR_FORMAT " in region [" PTR_FORMAT ", " PTR_FORMAT ")",
538 p2i(p), p2i(_containing_obj), p2i(from->bottom()), p2i(from->end()));
539 LogStream ls(log.error());
540 print_object(&ls, _containing_obj);
541 log.error("points to dead obj " PTR_FORMAT " in region [" PTR_FORMAT ", " PTR_FORMAT ")",
542 p2i(obj), p2i(to->bottom()), p2i(to->end()));
543 print_object(&ls, obj);
544 }
545 log.error("----------");
546 _failures = true;
547 failed = true;
548 _n_failures++;
549 }
550 }
551 }
552 };
553
554 class VerifyRemSetClosure : public G1VerificationClosure {
555 public:
556 VerifyRemSetClosure(G1CollectedHeap* g1h, VerifyOption vo) : G1VerificationClosure(g1h, vo) {}
557 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
558 virtual void do_oop(oop* p) { do_oop_work(p); }
559
560 template <class T>
561 void do_oop_work(T* p) {
562 assert(_containing_obj != NULL, "Precondition");
563 assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo),
564 "Precondition");
565 verify_remembered_set(p);
566 }
567
568 template <class T>
569 void verify_remembered_set(T* p) {
570 T heap_oop = oopDesc::load_heap_oop(p);
571 Log(gc, verify) log;
572 if (!oopDesc::is_null(heap_oop)) {
573 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
574 HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
575 HeapRegion* to = _g1h->heap_region_containing(obj);
576 if (from != NULL && to != NULL &&
577 from != to &&
578 !to->is_pinned()) {
579 jbyte cv_obj = *_bs->byte_for_const(_containing_obj);
580 jbyte cv_field = *_bs->byte_for_const(p);
581 const jbyte dirty = CardTableModRefBS::dirty_card_val();
582
583 bool is_bad = !(from->is_young()
584 || to->rem_set()->contains_reference(p)
585 || (_containing_obj->is_objArray() ?
586 cv_field == dirty :
587 cv_obj == dirty || cv_field == dirty));
588 if (is_bad) {
589 MutexLockerEx x(ParGCRareEvent_lock,
590 Mutex::_no_safepoint_check_flag);
591
592 if (!_failures) {
593 log.error("----------");
594 }
595 log.error("Missing rem set entry:");
596 log.error("Field " PTR_FORMAT " of obj " PTR_FORMAT ", in region " HR_FORMAT,
597 p2i(p), p2i(_containing_obj), HR_FORMAT_PARAMS(from));
598 ResourceMark rm;
599 LogStream ls(log.error());
600 _containing_obj->print_on(&ls);
601 log.error("points to obj " PTR_FORMAT " in region " HR_FORMAT, p2i(obj), HR_FORMAT_PARAMS(to));
602 if (obj->is_oop()) {
603 obj->print_on(&ls);
604 }
605 log.error("Obj head CTE = %d, field CTE = %d.", cv_obj, cv_field);
606 log.error("----------");
607 _failures = true;
608 _n_failures++;
609 }
610 }
611 }
612 }
613 };
614
615 // Closure that applies the given two closures in sequence.
616 class G1Mux2Closure : public OopClosure {
617 OopClosure* _c1;
618 OopClosure* _c2;
619 public:
620 G1Mux2Closure(OopClosure *c1, OopClosure *c2) { _c1 = c1; _c2 = c2; }
621 template <class T> inline void do_oop_work(T* p) {
622 // Apply first closure; then apply the second.
623 _c1->do_oop(p);
624 _c2->do_oop(p);
625 }
626 virtual inline void do_oop(oop* p) { do_oop_work(p); }
627 virtual inline void do_oop(narrowOop* p) { do_oop_work(p); }
628 };
629
630 // This really ought to be commoned up into OffsetTableContigSpace somehow.
631 // We would need a mechanism to make that code skip dead objects.
632
633 void HeapRegion::verify(VerifyOption vo,
634 bool* failures) const {
635 G1CollectedHeap* g1 = G1CollectedHeap::heap();
636 *failures = false;
637 HeapWord* p = bottom();
638 HeapWord* prev_p = NULL;
639 VerifyLiveClosure vl_cl(g1, vo);
640 VerifyRemSetClosure vr_cl(g1, vo);
641 bool is_region_humongous = is_humongous();
642 size_t object_num = 0;
643 while (p < top()) {
644 oop obj = oop(p);
645 size_t obj_size = block_size(p);
646 object_num += 1;
647
648 if (!g1->is_obj_dead_cond(obj, this, vo)) {
649 if (obj->is_oop()) {
650 Klass* klass = obj->klass();
651 bool is_metaspace_object = Metaspace::contains(klass) ||
652 (vo == VerifyOption_G1UsePrevMarking &&
653 ClassLoaderDataGraph::unload_list_contains(klass));
654 if (!is_metaspace_object) {
655 log_error(gc, verify)("klass " PTR_FORMAT " of object " PTR_FORMAT " "
656 "not metadata", p2i(klass), p2i(obj));
657 *failures = true;
658 return;
659 } else if (!klass->is_klass()) {
660 log_error(gc, verify)("klass " PTR_FORMAT " of object " PTR_FORMAT " "
661 "not a klass", p2i(klass), p2i(obj));
662 *failures = true;
663 return;
664 } else {
665 vl_cl.set_containing_obj(obj);
666 if (!g1->collector_state()->full_collection() || G1VerifyRSetsDuringFullGC) {
667 // verify liveness and rem_set
668 vr_cl.set_containing_obj(obj);
669 G1Mux2Closure mux(&vl_cl, &vr_cl);
670 obj->oop_iterate_no_header(&mux);
671
672 if (vr_cl.failures()) {
673 *failures = true;
674 }
675 if (G1MaxVerifyFailures >= 0 &&
676 vr_cl.n_failures() >= G1MaxVerifyFailures) {
677 return;
678 }
679 } else {
680 // verify only liveness
681 obj->oop_iterate_no_header(&vl_cl);
682 }
683 if (vl_cl.failures()) {
684 *failures = true;
685 }
686 if (G1MaxVerifyFailures >= 0 &&
687 vl_cl.n_failures() >= G1MaxVerifyFailures) {
688 return;
689 }
690 }
691 } else {
692 log_error(gc, verify)(PTR_FORMAT " not an oop", p2i(obj));
693 *failures = true;
694 return;
695 }
696 }
697 prev_p = p;
698 p += obj_size;
699 }
700
701 if (!is_young() && !is_empty()) {
702 _bot_part.verify();
703 }
704
705 if (is_region_humongous) {
706 oop obj = oop(this->humongous_start_region()->bottom());
707 if ((HeapWord*)obj > bottom() || (HeapWord*)obj + obj->size() < bottom()) {
708 log_error(gc, verify)("this humongous region is not part of its' humongous object " PTR_FORMAT, p2i(obj));
709 *failures = true;
710 return;
711 }
712 }
713
714 if (!is_region_humongous && p != top()) {
715 log_error(gc, verify)("end of last object " PTR_FORMAT " "
716 "does not match top " PTR_FORMAT, p2i(p), p2i(top()));
717 *failures = true;
718 return;
719 }
720
721 HeapWord* the_end = end();
722 // Do some extra BOT consistency checking for addresses in the
723 // range [top, end). BOT look-ups in this range should yield
724 // top. No point in doing that if top == end (there's nothing there).
725 if (p < the_end) {
726 // Look up top
727 HeapWord* addr_1 = p;
728 HeapWord* b_start_1 = _bot_part.block_start_const(addr_1);
729 if (b_start_1 != p) {
730 log_error(gc, verify)("BOT look up for top: " PTR_FORMAT " "
731 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
732 p2i(addr_1), p2i(b_start_1), p2i(p));
733 *failures = true;
734 return;
735 }
736
737 // Look up top + 1
738 HeapWord* addr_2 = p + 1;
739 if (addr_2 < the_end) {
740 HeapWord* b_start_2 = _bot_part.block_start_const(addr_2);
741 if (b_start_2 != p) {
742 log_error(gc, verify)("BOT look up for top + 1: " PTR_FORMAT " "
743 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
744 p2i(addr_2), p2i(b_start_2), p2i(p));
745 *failures = true;
746 return;
747 }
748 }
749
750 // Look up an address between top and end
751 size_t diff = pointer_delta(the_end, p) / 2;
752 HeapWord* addr_3 = p + diff;
753 if (addr_3 < the_end) {
754 HeapWord* b_start_3 = _bot_part.block_start_const(addr_3);
755 if (b_start_3 != p) {
756 log_error(gc, verify)("BOT look up for top + diff: " PTR_FORMAT " "
757 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
758 p2i(addr_3), p2i(b_start_3), p2i(p));
759 *failures = true;
760 return;
761 }
762 }
763
764 // Look up end - 1
765 HeapWord* addr_4 = the_end - 1;
766 HeapWord* b_start_4 = _bot_part.block_start_const(addr_4);
767 if (b_start_4 != p) {
768 log_error(gc, verify)("BOT look up for end - 1: " PTR_FORMAT " "
769 " yielded " PTR_FORMAT ", expecting " PTR_FORMAT,
770 p2i(addr_4), p2i(b_start_4), p2i(p));
771 *failures = true;
772 return;
773 }
774 }
775
776 verify_strong_code_roots(vo, failures);
777 }
778
779 void HeapRegion::verify() const {
780 bool dummy = false;
781 verify(VerifyOption_G1UsePrevMarking, /* failures */ &dummy);
782 }
783
784 void HeapRegion::verify_rem_set(VerifyOption vo, bool* failures) const {
785 G1CollectedHeap* g1 = G1CollectedHeap::heap();
786 *failures = false;
787 HeapWord* p = bottom();
788 HeapWord* prev_p = NULL;
789 VerifyRemSetClosure vr_cl(g1, vo);
790 while (p < top()) {
791 oop obj = oop(p);
792 size_t obj_size = block_size(p);
793
794 if (!g1->is_obj_dead_cond(obj, this, vo)) {
795 if (obj->is_oop()) {
796 vr_cl.set_containing_obj(obj);
797 obj->oop_iterate_no_header(&vr_cl);
798
799 if (vr_cl.failures()) {
800 *failures = true;
801 }
802 if (G1MaxVerifyFailures >= 0 &&
803 vr_cl.n_failures() >= G1MaxVerifyFailures) {
804 return;
805 }
806 } else {
807 log_error(gc, verify)(PTR_FORMAT " not an oop", p2i(obj));
808 *failures = true;
809 return;
810 }
811 }
812
813 prev_p = p;
814 p += obj_size;
815 }
816 }
817
818 void HeapRegion::verify_rem_set() const {
819 bool failures = false;
820 verify_rem_set(VerifyOption_G1UsePrevMarking, &failures);
821 guarantee(!failures, "HeapRegion RemSet verification failed");
822 }
823
824 void HeapRegion::prepare_for_compaction(CompactPoint* cp) {
825 scan_and_forward(this, cp);
826 }
827
828 // G1OffsetTableContigSpace code; copied from space.cpp. Hope this can go
829 // away eventually.
830
831 void G1ContiguousSpace::clear(bool mangle_space) {
832 set_top(bottom());
833 CompactibleSpace::clear(mangle_space);
834 reset_bot();
835 }
836
837 #ifndef PRODUCT
838 void G1ContiguousSpace::mangle_unused_area() {
839 mangle_unused_area_complete();
840 }
841
842 void G1ContiguousSpace::mangle_unused_area_complete() {
843 SpaceMangler::mangle_region(MemRegion(top(), end()));
844 }
845 #endif
846
847 void G1ContiguousSpace::print() const {
848 print_short();
849 tty->print_cr(" [" INTPTR_FORMAT ", " INTPTR_FORMAT ", "
850 INTPTR_FORMAT ", " INTPTR_FORMAT ")",
851 p2i(bottom()), p2i(top()), p2i(_bot_part.threshold()), p2i(end()));
852 }
853
854 HeapWord* G1ContiguousSpace::initialize_threshold() {
855 return _bot_part.initialize_threshold();
856 }
857
858 HeapWord* G1ContiguousSpace::cross_threshold(HeapWord* start,
859 HeapWord* end) {
860 _bot_part.alloc_block(start, end);
861 return _bot_part.threshold();
862 }
863
864 void G1ContiguousSpace::record_timestamp() {
865 G1CollectedHeap* g1h = G1CollectedHeap::heap();
866 uint curr_gc_time_stamp = g1h->get_gc_time_stamp();
867
868 if (_gc_time_stamp < curr_gc_time_stamp) {
869 _gc_time_stamp = curr_gc_time_stamp;
870 }
871 }
872
873 void G1ContiguousSpace::safe_object_iterate(ObjectClosure* blk) {
874 object_iterate(blk);
875 }
876
877 void G1ContiguousSpace::object_iterate(ObjectClosure* blk) {
878 HeapWord* p = bottom();
879 while (p < top()) {
880 if (block_is_obj(p)) {
881 blk->do_object(oop(p));
882 }
883 p += block_size(p);
884 }
885 }
886
887 G1ContiguousSpace::G1ContiguousSpace(G1BlockOffsetTable* bot) :
888 _bot_part(bot, this),
889 _par_alloc_lock(Mutex::leaf, "OffsetTableContigSpace par alloc lock", true),
890 _gc_time_stamp(0)
891 {
892 }
893
894 void G1ContiguousSpace::initialize(MemRegion mr, bool clear_space, bool mangle_space) {
895 CompactibleSpace::initialize(mr, clear_space, mangle_space);
896 _top = bottom();
897 set_saved_mark_word(NULL);
898 reset_bot();
899 }