1 /*
2 * Copyright (c) 2016, 2020, 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/g1CollectedHeap.inline.hpp"
29 #include "gc/g1/g1ConcurrentMarkThread.hpp"
30 #include "gc/g1/g1HeapVerifier.hpp"
31 #include "gc/g1/g1Policy.hpp"
32 #include "gc/g1/g1RemSet.hpp"
33 #include "gc/g1/g1RootProcessor.hpp"
34 #include "gc/g1/heapRegion.inline.hpp"
35 #include "gc/g1/heapRegionRemSet.hpp"
36 #include "gc/g1/g1StringDedup.hpp"
37 #include "logging/log.hpp"
38 #include "logging/logStream.hpp"
39 #include "memory/iterator.inline.hpp"
40 #include "memory/resourceArea.hpp"
41 #include "memory/universe.hpp"
42 #include "oops/access.inline.hpp"
43 #include "oops/compressedOops.inline.hpp"
44 #include "oops/oop.inline.hpp"
45 #include "runtime/handles.inline.hpp"
46
47 int G1HeapVerifier::_enabled_verification_types = G1HeapVerifier::G1VerifyAll;
48
49 class VerifyRootsClosure: public OopClosure {
50 private:
51 G1CollectedHeap* _g1h;
52 VerifyOption _vo;
53 bool _failures;
54 public:
55 // _vo == UsePrevMarking -> use "prev" marking information,
56 // _vo == UseNextMarking -> use "next" marking information,
57 // _vo == UseFullMarking -> use "next" marking bitmap but no TAMS
58 VerifyRootsClosure(VerifyOption vo) :
59 _g1h(G1CollectedHeap::heap()),
60 _vo(vo),
61 _failures(false) { }
62
63 bool failures() { return _failures; }
64
65 template <class T> void do_oop_work(T* p) {
66 T heap_oop = RawAccess<>::oop_load(p);
67 if (!CompressedOops::is_null(heap_oop)) {
68 oop obj = CompressedOops::decode_not_null(heap_oop);
69 if (_g1h->is_obj_dead_cond(obj, _vo)) {
70 Log(gc, verify) log;
71 log.error("Root location " PTR_FORMAT " points to dead obj " PTR_FORMAT " vo %d", p2i(p), p2i(obj), _vo);
72 ResourceMark rm;
73 LogStream ls(log.error());
74 obj->print_on(&ls);
75 _failures = true;
76 }
77 }
78 }
79
80 void do_oop(oop* p) { do_oop_work(p); }
81 void do_oop(narrowOop* p) { do_oop_work(p); }
82 };
83
84 class G1VerifyCodeRootOopClosure: public OopClosure {
85 G1CollectedHeap* _g1h;
86 OopClosure* _root_cl;
87 nmethod* _nm;
88 VerifyOption _vo;
89 bool _failures;
90
91 template <class T> void do_oop_work(T* p) {
92 // First verify that this root is live
93 _root_cl->do_oop(p);
94
95 if (!G1VerifyHeapRegionCodeRoots) {
96 // We're not verifying the code roots attached to heap region.
97 return;
98 }
99
100 // Don't check the code roots during marking verification in a full GC
101 if (_vo == VerifyOption_G1UseFullMarking) {
102 return;
103 }
104
105 // Now verify that the current nmethod (which contains p) is
106 // in the code root list of the heap region containing the
107 // object referenced by p.
108
109 T heap_oop = RawAccess<>::oop_load(p);
110 if (!CompressedOops::is_null(heap_oop)) {
111 oop obj = CompressedOops::decode_not_null(heap_oop);
112
113 // Now fetch the region containing the object
114 HeapRegion* hr = _g1h->heap_region_containing(obj);
115 HeapRegionRemSet* hrrs = hr->rem_set();
116 // Verify that the strong code root list for this region
117 // contains the nmethod
118 if (!hrrs->strong_code_roots_list_contains(_nm)) {
119 log_error(gc, verify)("Code root location " PTR_FORMAT " "
120 "from nmethod " PTR_FORMAT " not in strong "
121 "code roots for region [" PTR_FORMAT "," PTR_FORMAT ")",
122 p2i(p), p2i(_nm), p2i(hr->bottom()), p2i(hr->end()));
123 _failures = true;
124 }
125 }
126 }
127
128 public:
129 G1VerifyCodeRootOopClosure(G1CollectedHeap* g1h, OopClosure* root_cl, VerifyOption vo):
130 _g1h(g1h), _root_cl(root_cl), _nm(NULL), _vo(vo), _failures(false) {}
131
132 void do_oop(oop* p) { do_oop_work(p); }
133 void do_oop(narrowOop* p) { do_oop_work(p); }
134
135 void set_nmethod(nmethod* nm) { _nm = nm; }
136 bool failures() { return _failures; }
137 };
138
139 class G1VerifyCodeRootBlobClosure: public CodeBlobClosure {
140 G1VerifyCodeRootOopClosure* _oop_cl;
141
142 public:
143 G1VerifyCodeRootBlobClosure(G1VerifyCodeRootOopClosure* oop_cl):
144 _oop_cl(oop_cl) {}
145
146 void do_code_blob(CodeBlob* cb) {
147 nmethod* nm = cb->as_nmethod_or_null();
148 if (nm != NULL) {
149 _oop_cl->set_nmethod(nm);
150 nm->oops_do(_oop_cl);
151 }
152 }
153 };
154
155 class YoungRefCounterClosure : public OopClosure {
156 G1CollectedHeap* _g1h;
157 int _count;
158 public:
159 YoungRefCounterClosure(G1CollectedHeap* g1h) : _g1h(g1h), _count(0) {}
160 void do_oop(oop* p) { if (_g1h->is_in_young(*p)) { _count++; } }
161 void do_oop(narrowOop* p) { ShouldNotReachHere(); }
162
163 int count() { return _count; }
164 void reset_count() { _count = 0; };
165 };
166
167 class VerifyCLDClosure: public CLDClosure {
168 YoungRefCounterClosure _young_ref_counter_closure;
169 OopClosure *_oop_closure;
170 public:
171 VerifyCLDClosure(G1CollectedHeap* g1h, OopClosure* cl) : _young_ref_counter_closure(g1h), _oop_closure(cl) {}
172 void do_cld(ClassLoaderData* cld) {
173 cld->oops_do(_oop_closure, ClassLoaderData::_claim_none);
174
175 _young_ref_counter_closure.reset_count();
176 cld->oops_do(&_young_ref_counter_closure, ClassLoaderData::_claim_none);
177 if (_young_ref_counter_closure.count() > 0) {
178 guarantee(cld->has_modified_oops(), "CLD " PTR_FORMAT ", has young %d refs but is not dirty.", p2i(cld), _young_ref_counter_closure.count());
179 }
180 }
181 };
182
183 class VerifyLivenessOopClosure: public BasicOopIterateClosure {
184 G1CollectedHeap* _g1h;
185 VerifyOption _vo;
186 oop _o;
187 public:
188 VerifyLivenessOopClosure(G1CollectedHeap* g1h, VerifyOption vo, oop o):
189 _g1h(g1h), _vo(vo), _o(o)
190 { }
191 void do_oop(narrowOop *p) { do_oop_work(p); }
192 void do_oop( oop *p) { do_oop_work(p); }
193
194 template <class T> void do_oop_work(T *p) {
195 oop obj = RawAccess<>::oop_load(p);
196 guarantee(obj == NULL || !_g1h->is_obj_dead_cond(obj, _vo),
197 "vo %d Dead object " PTR_FORMAT " (%s) referenced by a not dead object " PTR_FORMAT " (%s) _g1h->is_obj_dead_cond(obj, _vo) %d marked %d since prev mark %d since next mark %d",
198 _vo,
199 p2i(obj), _g1h->heap_region_containing(obj)->get_short_type_str(),
200 p2i(_o), _g1h->heap_region_containing(_o)->get_short_type_str(),
201 _g1h->is_obj_dead_cond(obj, _vo),
202 _g1h->concurrent_mark()->prev_mark_bitmap()->is_marked(_o),
203 _g1h->heap_region_containing(_o)->obj_allocated_since_prev_marking(_o),
204 _g1h->heap_region_containing(_o)->obj_allocated_since_next_marking(_o)
205 );
206 }
207 };
208
209 class VerifyObjsInRegionClosure: public ObjectClosure {
210 private:
211 G1CollectedHeap* _g1h;
212 size_t _live_bytes;
213 HeapRegion *_hr;
214 VerifyOption _vo;
215 public:
216 // _vo == UsePrevMarking -> use "prev" marking information,
217 // _vo == UseNextMarking -> use "next" marking information,
218 // _vo == UseFullMarking -> use "next" marking bitmap but no TAMS.
219 VerifyObjsInRegionClosure(HeapRegion *hr, VerifyOption vo)
220 : _live_bytes(0), _hr(hr), _vo(vo) {
221 _g1h = G1CollectedHeap::heap();
222 }
223 void do_object(oop o) {
224 VerifyLivenessOopClosure isLive(_g1h, _vo, o);
225 assert(o != NULL, "Huh?");
226 if (!_g1h->is_obj_dead_cond(o, _vo)) {
227 // If the object is alive according to the full gc mark,
228 // then verify that the marking information agrees.
229 // Note we can't verify the contra-positive of the
230 // above: if the object is dead (according to the mark
231 // word), it may not be marked, or may have been marked
232 // but has since became dead, or may have been allocated
233 // since the last marking.
234 if (_vo == VerifyOption_G1UseFullMarking) {
235 guarantee(!_g1h->is_obj_dead(o), "Full GC marking and concurrent mark mismatch");
236 }
237
238 o->oop_iterate(&isLive);
239 if (!_hr->obj_allocated_since_prev_marking(o)) {
240 size_t obj_size = o->size(); // Make sure we don't overflow
241 _live_bytes += (obj_size * HeapWordSize);
242 }
243 }
244 }
245 size_t live_bytes() { return _live_bytes; }
246 };
247
248 class VerifyArchiveOopClosure: public BasicOopIterateClosure {
249 HeapRegion* _hr;
250 public:
251 VerifyArchiveOopClosure(HeapRegion *hr)
252 : _hr(hr) { }
253 void do_oop(narrowOop *p) { do_oop_work(p); }
254 void do_oop( oop *p) { do_oop_work(p); }
255
256 template <class T> void do_oop_work(T *p) {
257 oop obj = RawAccess<>::oop_load(p);
258
259 if (_hr->is_open_archive()) {
260 guarantee(obj == NULL || G1ArchiveAllocator::is_archived_object(obj),
261 "Archive object at " PTR_FORMAT " references a non-archive object at " PTR_FORMAT,
262 p2i(p), p2i(obj));
263 } else {
264 assert(_hr->is_closed_archive(), "should be closed archive region");
265 guarantee(obj == NULL || G1ArchiveAllocator::is_closed_archive_object(obj),
266 "Archive object at " PTR_FORMAT " references a non-archive object at " PTR_FORMAT,
267 p2i(p), p2i(obj));
268 }
269 }
270 };
271
272 class VerifyObjectInArchiveRegionClosure: public ObjectClosure {
273 HeapRegion* _hr;
274 public:
275 VerifyObjectInArchiveRegionClosure(HeapRegion *hr, bool verbose)
276 : _hr(hr) { }
277 // Verify that all object pointers are to archive regions.
278 void do_object(oop o) {
279 VerifyArchiveOopClosure checkOop(_hr);
280 assert(o != NULL, "Should not be here for NULL oops");
281 o->oop_iterate(&checkOop);
282 }
283 };
284
285 // Should be only used at CDS dump time
286 class VerifyReadyForArchivingRegionClosure : public HeapRegionClosure {
287 bool _seen_free;
288 bool _has_holes;
289 bool _has_unexpected_holes;
290 bool _has_humongous;
291 public:
292 bool has_holes() {return _has_holes;}
293 bool has_unexpected_holes() {return _has_unexpected_holes;}
294 bool has_humongous() {return _has_humongous;}
295
296 VerifyReadyForArchivingRegionClosure() : HeapRegionClosure() {
297 _seen_free = false;
298 _has_holes = false;
299 _has_unexpected_holes = false;
300 _has_humongous = false;
301 }
302 virtual bool do_heap_region(HeapRegion* hr) {
303 const char* hole = "";
304
305 if (hr->is_free()) {
306 _seen_free = true;
307 } else {
308 if (_seen_free) {
309 _has_holes = true;
310 if (hr->is_humongous()) {
311 hole = " hole";
312 } else {
313 _has_unexpected_holes = true;
314 hole = " hole **** unexpected ****";
315 }
316 }
317 }
318 if (hr->is_humongous()) {
319 _has_humongous = true;
320 }
321 log_info(gc, region, cds)("HeapRegion " INTPTR_FORMAT " %s%s", p2i(hr->bottom()), hr->get_type_str(), hole);
322 return false;
323 }
324 };
325
326 // We want all used regions to be moved to the bottom-end of the heap, so we have
327 // a contiguous range of free regions at the top end of the heap. This way, we can
328 // avoid fragmentation while allocating the archive regions.
329 //
330 // Before calling this, a full GC should have been executed with a single worker thread,
331 // so that no old regions would be moved to the middle of the heap.
332 void G1HeapVerifier::verify_ready_for_archiving() {
333 VerifyReadyForArchivingRegionClosure cl;
334 G1CollectedHeap::heap()->heap_region_iterate(&cl);
335 if (cl.has_holes()) {
336 log_warning(gc, verify)("All free regions should be at the top end of the heap, but"
337 " we found holes. This is probably caused by (unmovable) humongous"
338 " allocations or active GCLocker, and may lead to fragmentation while"
339 " writing archive heap memory regions.");
340 }
341 if (cl.has_humongous()) {
342 log_warning(gc, verify)("(Unmovable) humongous regions have been found and"
343 " may lead to fragmentation while"
344 " writing archive heap memory regions.");
345 }
346 }
347
348 class VerifyArchivePointerRegionClosure: public HeapRegionClosure {
349 virtual bool do_heap_region(HeapRegion* r) {
350 if (r->is_archive()) {
351 VerifyObjectInArchiveRegionClosure verify_oop_pointers(r, false);
352 r->object_iterate(&verify_oop_pointers);
353 }
354 return false;
355 }
356 };
357
358 void G1HeapVerifier::verify_archive_regions() {
359 G1CollectedHeap* g1h = G1CollectedHeap::heap();
360 VerifyArchivePointerRegionClosure cl;
361 g1h->heap_region_iterate(&cl);
362 }
363
364 class VerifyRegionClosure: public HeapRegionClosure {
365 private:
366 bool _par;
367 VerifyOption _vo;
368 bool _failures;
369 public:
370 // _vo == UsePrevMarking -> use "prev" marking information,
371 // _vo == UseNextMarking -> use "next" marking information,
372 // _vo == UseFullMarking -> use "next" marking bitmap but no TAMS
373 VerifyRegionClosure(bool par, VerifyOption vo)
374 : _par(par),
375 _vo(vo),
376 _failures(false) {}
377
378 bool failures() {
379 return _failures;
380 }
381
382 bool do_heap_region(HeapRegion* r) {
383 guarantee(!r->has_index_in_opt_cset(), "Region %u still has opt collection set index %u", r->hrm_index(), r->index_in_opt_cset());
384 guarantee(!r->is_young() || r->rem_set()->is_complete(), "Remembered set for Young region %u must be complete, is %s", r->hrm_index(), r->rem_set()->get_state_str());
385 // Humongous and old regions regions might be of any state, so can't check here.
386 guarantee(!r->is_free() || !r->rem_set()->is_tracked(), "Remembered set for free region %u must be untracked, is %s", r->hrm_index(), r->rem_set()->get_state_str());
387 // Verify that the continues humongous regions' remembered set state matches the
388 // one from the starts humongous region.
389 if (r->is_continues_humongous()) {
390 if (r->rem_set()->get_state_str() != r->humongous_start_region()->rem_set()->get_state_str()) {
391 log_error(gc, verify)("Remset states differ: Region %u (%s) remset %s with starts region %u (%s) remset %s",
392 r->hrm_index(),
393 r->get_short_type_str(),
394 r->rem_set()->get_state_str(),
395 r->humongous_start_region()->hrm_index(),
396 r->humongous_start_region()->get_short_type_str(),
397 r->humongous_start_region()->rem_set()->get_state_str());
398 _failures = true;
399 }
400 }
401 // For archive regions, verify there are no heap pointers to
402 // non-pinned regions. For all others, verify liveness info.
403 if (r->is_closed_archive()) {
404 VerifyObjectInArchiveRegionClosure verify_oop_pointers(r, false);
405 r->object_iterate(&verify_oop_pointers);
406 return true;
407 } else if (r->is_open_archive()) {
408 VerifyObjsInRegionClosure verify_open_archive_oop(r, _vo);
409 r->object_iterate(&verify_open_archive_oop);
410 return true;
411 } else if (!r->is_continues_humongous()) {
412 bool failures = false;
413 r->verify(_vo, &failures);
414 if (failures) {
415 _failures = true;
416 } else if (!r->is_starts_humongous()) {
417 VerifyObjsInRegionClosure not_dead_yet_cl(r, _vo);
418 r->object_iterate(¬_dead_yet_cl);
419 if (_vo != VerifyOption_G1UseNextMarking) {
420 if (r->max_live_bytes() < not_dead_yet_cl.live_bytes()) {
421 log_error(gc, verify)("[" PTR_FORMAT "," PTR_FORMAT "] max_live_bytes " SIZE_FORMAT " < calculated " SIZE_FORMAT,
422 p2i(r->bottom()), p2i(r->end()), r->max_live_bytes(), not_dead_yet_cl.live_bytes());
423 _failures = true;
424 }
425 } else {
426 // When vo == UseNextMarking we cannot currently do a sanity
427 // check on the live bytes as the calculation has not been
428 // finalized yet.
429 }
430 }
431 }
432 return false; // stop the region iteration if we hit a failure
433 }
434 };
435
436 // This is the task used for parallel verification of the heap regions
437
438 class G1ParVerifyTask: public AbstractGangTask {
439 private:
440 G1CollectedHeap* _g1h;
441 VerifyOption _vo;
442 bool _failures;
443 HeapRegionClaimer _hrclaimer;
444
445 public:
446 // _vo == UsePrevMarking -> use "prev" marking information,
447 // _vo == UseNextMarking -> use "next" marking information,
448 // _vo == UseFullMarking -> use "next" marking bitmap but no TAMS
449 G1ParVerifyTask(G1CollectedHeap* g1h, VerifyOption vo) :
450 AbstractGangTask("Parallel verify task"),
451 _g1h(g1h),
452 _vo(vo),
453 _failures(false),
454 _hrclaimer(g1h->workers()->active_workers()) {}
455
456 bool failures() {
457 return _failures;
458 }
459
460 void work(uint worker_id) {
461 VerifyRegionClosure blk(true, _vo);
462 _g1h->heap_region_par_iterate_from_worker_offset(&blk, &_hrclaimer, worker_id);
463 if (blk.failures()) {
464 _failures = true;
465 }
466 }
467 };
468
469 void G1HeapVerifier::enable_verification_type(G1VerifyType type) {
470 // First enable will clear _enabled_verification_types.
471 if (_enabled_verification_types == G1VerifyAll) {
472 _enabled_verification_types = type;
473 } else {
474 _enabled_verification_types |= type;
475 }
476 }
477
478 bool G1HeapVerifier::should_verify(G1VerifyType type) {
479 return (_enabled_verification_types & type) == type;
480 }
481
482 void G1HeapVerifier::verify(VerifyOption vo) {
483 if (!SafepointSynchronize::is_at_safepoint()) {
484 log_info(gc, verify)("Skipping verification. Not at safepoint.");
485 }
486
487 assert(Thread::current()->is_VM_thread(),
488 "Expected to be executed serially by the VM thread at this point");
489
490 log_debug(gc, verify)("Roots");
491 VerifyRootsClosure rootsCl(vo);
492 VerifyCLDClosure cldCl(_g1h, &rootsCl);
493
494 // We apply the relevant closures to all the oops in the
495 // system dictionary, class loader data graph, the string table
496 // and the nmethods in the code cache.
497 G1VerifyCodeRootOopClosure codeRootsCl(_g1h, &rootsCl, vo);
498 G1VerifyCodeRootBlobClosure blobsCl(&codeRootsCl);
499
500 {
501 G1RootProcessor root_processor(_g1h, 1);
502 root_processor.process_all_roots(&rootsCl, &cldCl, &blobsCl);
503 }
504
505 bool failures = rootsCl.failures() || codeRootsCl.failures();
506
507 if (!_g1h->policy()->collector_state()->in_full_gc()) {
508 // If we're verifying during a full GC then the region sets
509 // will have been torn down at the start of the GC. Therefore
510 // verifying the region sets will fail. So we only verify
511 // the region sets when not in a full GC.
512 log_debug(gc, verify)("HeapRegionSets");
513 verify_region_sets();
514 }
515
516 log_debug(gc, verify)("HeapRegions");
517 if (GCParallelVerificationEnabled && ParallelGCThreads > 1) {
518
519 G1ParVerifyTask task(_g1h, vo);
520 _g1h->workers()->run_task(&task);
521 if (task.failures()) {
522 failures = true;
523 }
524
525 } else {
526 VerifyRegionClosure blk(false, vo);
527 _g1h->heap_region_iterate(&blk);
528 if (blk.failures()) {
529 failures = true;
530 }
531 }
532
533 if (G1StringDedup::is_enabled()) {
534 log_debug(gc, verify)("StrDedup");
535 G1StringDedup::verify();
536 }
537
538 if (failures) {
539 log_error(gc, verify)("Heap after failed verification (kind %d):", vo);
540 // It helps to have the per-region information in the output to
541 // help us track down what went wrong. This is why we call
542 // print_extended_on() instead of print_on().
543 Log(gc, verify) log;
544 ResourceMark rm;
545 LogStream ls(log.error());
546 _g1h->print_extended_on(&ls);
547 }
548 guarantee(!failures, "there should not have been any failures");
549 }
550
551 // Heap region set verification
552
553 class VerifyRegionListsClosure : public HeapRegionClosure {
554 private:
555 HeapRegionSet* _old_set;
556 HeapRegionSet* _archive_set;
557 HeapRegionSet* _humongous_set;
558 HeapRegionManager* _hrm;
559
560 public:
561 uint _old_count;
562 uint _archive_count;
563 uint _humongous_count;
564 uint _free_count;
565
566 VerifyRegionListsClosure(HeapRegionSet* old_set,
567 HeapRegionSet* archive_set,
568 HeapRegionSet* humongous_set,
569 HeapRegionManager* hrm) :
570 _old_set(old_set), _archive_set(archive_set), _humongous_set(humongous_set), _hrm(hrm),
571 _old_count(), _archive_count(), _humongous_count(), _free_count(){ }
572
573 bool do_heap_region(HeapRegion* hr) {
574 if (hr->is_young()) {
575 // TODO
576 } else if (hr->is_humongous()) {
577 assert(hr->containing_set() == _humongous_set, "Heap region %u is humongous but not in humongous set.", hr->hrm_index());
578 _humongous_count++;
579 } else if (hr->is_empty()) {
580 assert(_hrm->is_free(hr), "Heap region %u is empty but not on the free list.", hr->hrm_index());
581 _free_count++;
582 } else if (hr->is_archive()) {
583 assert(hr->containing_set() == _archive_set, "Heap region %u is archive but not in the archive set.", hr->hrm_index());
584 _archive_count++;
585 } else if (hr->is_old()) {
586 assert(hr->containing_set() == _old_set, "Heap region %u is old but not in the old set.", hr->hrm_index());
587 _old_count++;
588 } else {
589 // There are no other valid region types. Check for one invalid
590 // one we can identify: pinned without old or humongous set.
591 assert(!hr->is_pinned(), "Heap region %u is pinned but not old (archive) or humongous.", hr->hrm_index());
592 ShouldNotReachHere();
593 }
594 return false;
595 }
596
597 void verify_counts(HeapRegionSet* old_set, HeapRegionSet* archive_set, HeapRegionSet* humongous_set, HeapRegionManager* free_list) {
598 guarantee(old_set->length() == _old_count, "Old set count mismatch. Expected %u, actual %u.", old_set->length(), _old_count);
599 guarantee(archive_set->length() == _archive_count, "Archive set count mismatch. Expected %u, actual %u.", archive_set->length(), _archive_count);
600 guarantee(humongous_set->length() == _humongous_count, "Hum set count mismatch. Expected %u, actual %u.", humongous_set->length(), _humongous_count);
601 guarantee(free_list->num_free_regions() == _free_count, "Free list count mismatch. Expected %u, actual %u.", free_list->num_free_regions(), _free_count);
602 }
603 };
604
605 void G1HeapVerifier::verify_region_sets() {
606 assert_heap_locked_or_at_safepoint(true /* should_be_vm_thread */);
607
608 // First, check the explicit lists.
609 _g1h->_hrm->verify();
610
611 // Finally, make sure that the region accounting in the lists is
612 // consistent with what we see in the heap.
613
614 VerifyRegionListsClosure cl(&_g1h->_old_set, &_g1h->_archive_set, &_g1h->_humongous_set, _g1h->_hrm);
615 _g1h->heap_region_iterate(&cl);
616 cl.verify_counts(&_g1h->_old_set, &_g1h->_archive_set, &_g1h->_humongous_set, _g1h->_hrm);
617 }
618
619 void G1HeapVerifier::prepare_for_verify() {
620 if (SafepointSynchronize::is_at_safepoint() || ! UseTLAB) {
621 _g1h->ensure_parsability(false);
622 }
623 }
624
625 double G1HeapVerifier::verify(G1VerifyType type, VerifyOption vo, const char* msg) {
626 double verify_time_ms = 0.0;
627
628 if (should_verify(type) && _g1h->total_collections() >= VerifyGCStartAt) {
629 double verify_start = os::elapsedTime();
630 prepare_for_verify();
631 Universe::verify(vo, msg);
632 verify_time_ms = (os::elapsedTime() - verify_start) * 1000;
633 }
634
635 return verify_time_ms;
636 }
637
638 void G1HeapVerifier::verify_before_gc(G1VerifyType type) {
639 if (VerifyBeforeGC) {
640 double verify_time_ms = verify(type, VerifyOption_G1UsePrevMarking, "Before GC");
641 _g1h->phase_times()->record_verify_before_time_ms(verify_time_ms);
642 }
643 }
644
645 void G1HeapVerifier::verify_after_gc(G1VerifyType type) {
646 if (VerifyAfterGC) {
647 double verify_time_ms = verify(type, VerifyOption_G1UsePrevMarking, "After GC");
648 _g1h->phase_times()->record_verify_after_time_ms(verify_time_ms);
649 }
650 }
651
652
653 #ifndef PRODUCT
654 class G1VerifyCardTableCleanup: public HeapRegionClosure {
655 G1HeapVerifier* _verifier;
656 public:
657 G1VerifyCardTableCleanup(G1HeapVerifier* verifier)
658 : _verifier(verifier) { }
659 virtual bool do_heap_region(HeapRegion* r) {
660 if (r->is_survivor()) {
661 _verifier->verify_dirty_region(r);
662 } else {
663 _verifier->verify_not_dirty_region(r);
664 }
665 return false;
666 }
667 };
668
669 void G1HeapVerifier::verify_card_table_cleanup() {
670 if (G1VerifyCTCleanup || VerifyAfterGC) {
671 G1VerifyCardTableCleanup cleanup_verifier(this);
672 _g1h->heap_region_iterate(&cleanup_verifier);
673 }
674 }
675
676 void G1HeapVerifier::verify_not_dirty_region(HeapRegion* hr) {
677 // All of the region should be clean.
678 G1CardTable* ct = _g1h->card_table();
679 MemRegion mr(hr->bottom(), hr->end());
680 ct->verify_not_dirty_region(mr);
681 }
682
683 void G1HeapVerifier::verify_dirty_region(HeapRegion* hr) {
684 // We cannot guarantee that [bottom(),end()] is dirty. Threads
685 // dirty allocated blocks as they allocate them. The thread that
686 // retires each region and replaces it with a new one will do a
687 // maximal allocation to fill in [pre_dummy_top(),end()] but will
688 // not dirty that area (one less thing to have to do while holding
689 // a lock). So we can only verify that [bottom(),pre_dummy_top()]
690 // is dirty.
691 G1CardTable* ct = _g1h->card_table();
692 MemRegion mr(hr->bottom(), hr->pre_dummy_top());
693 if (hr->is_young()) {
694 ct->verify_g1_young_region(mr);
695 } else {
696 ct->verify_dirty_region(mr);
697 }
698 }
699
700 class G1VerifyDirtyYoungListClosure : public HeapRegionClosure {
701 private:
702 G1HeapVerifier* _verifier;
703 public:
704 G1VerifyDirtyYoungListClosure(G1HeapVerifier* verifier) : HeapRegionClosure(), _verifier(verifier) { }
705 virtual bool do_heap_region(HeapRegion* r) {
706 _verifier->verify_dirty_region(r);
707 return false;
708 }
709 };
710
711 void G1HeapVerifier::verify_dirty_young_regions() {
712 G1VerifyDirtyYoungListClosure cl(this);
713 _g1h->collection_set()->iterate(&cl);
714 }
715
716 bool G1HeapVerifier::verify_no_bits_over_tams(const char* bitmap_name, const G1CMBitMap* const bitmap,
717 HeapWord* tams, HeapWord* end) {
718 guarantee(tams <= end,
719 "tams: " PTR_FORMAT " end: " PTR_FORMAT, p2i(tams), p2i(end));
720 HeapWord* result = bitmap->get_next_marked_addr(tams, end);
721 if (result < end) {
722 log_error(gc, verify)("## wrong marked address on %s bitmap: " PTR_FORMAT, bitmap_name, p2i(result));
723 log_error(gc, verify)("## %s tams: " PTR_FORMAT " end: " PTR_FORMAT, bitmap_name, p2i(tams), p2i(end));
724 return false;
725 }
726 return true;
727 }
728
729 bool G1HeapVerifier::verify_bitmaps(const char* caller, HeapRegion* hr) {
730 const G1CMBitMap* const prev_bitmap = _g1h->concurrent_mark()->prev_mark_bitmap();
731 const G1CMBitMap* const next_bitmap = _g1h->concurrent_mark()->next_mark_bitmap();
732
733 HeapWord* ptams = hr->prev_top_at_mark_start();
734 HeapWord* ntams = hr->next_top_at_mark_start();
735 HeapWord* end = hr->end();
736
737 bool res_p = verify_no_bits_over_tams("prev", prev_bitmap, ptams, end);
738
739 bool res_n = true;
740 // We cannot verify the next bitmap while we are about to clear it.
741 if (!_g1h->collector_state()->clearing_next_bitmap()) {
742 res_n = verify_no_bits_over_tams("next", next_bitmap, ntams, end);
743 }
744 if (!res_p || !res_n) {
745 log_error(gc, verify)("#### Bitmap verification failed for " HR_FORMAT, HR_FORMAT_PARAMS(hr));
746 log_error(gc, verify)("#### Caller: %s", caller);
747 return false;
748 }
749 return true;
750 }
751
752 void G1HeapVerifier::check_bitmaps(const char* caller, HeapRegion* hr) {
753 if (!G1VerifyBitmaps) {
754 return;
755 }
756
757 guarantee(verify_bitmaps(caller, hr), "bitmap verification");
758 }
759
760 class G1VerifyBitmapClosure : public HeapRegionClosure {
761 private:
762 const char* _caller;
763 G1HeapVerifier* _verifier;
764 bool _failures;
765
766 public:
767 G1VerifyBitmapClosure(const char* caller, G1HeapVerifier* verifier) :
768 _caller(caller), _verifier(verifier), _failures(false) { }
769
770 bool failures() { return _failures; }
771
772 virtual bool do_heap_region(HeapRegion* hr) {
773 bool result = _verifier->verify_bitmaps(_caller, hr);
774 if (!result) {
775 _failures = true;
776 }
777 return false;
778 }
779 };
780
781 void G1HeapVerifier::check_bitmaps(const char* caller) {
782 if (!G1VerifyBitmaps) {
783 return;
784 }
785
786 G1VerifyBitmapClosure cl(caller, this);
787 _g1h->heap_region_iterate(&cl);
788 guarantee(!cl.failures(), "bitmap verification");
789 }
790
791 class G1CheckRegionAttrTableClosure : public HeapRegionClosure {
792 private:
793 bool _failures;
794
795 public:
796 G1CheckRegionAttrTableClosure() : HeapRegionClosure(), _failures(false) { }
797
798 virtual bool do_heap_region(HeapRegion* hr) {
799 uint i = hr->hrm_index();
800 G1HeapRegionAttr region_attr = (G1HeapRegionAttr) G1CollectedHeap::heap()->_region_attr.get_by_index(i);
801 if (hr->is_humongous()) {
802 if (hr->in_collection_set()) {
803 log_error(gc, verify)("## humongous region %u in CSet", i);
804 _failures = true;
805 return true;
806 }
807 if (region_attr.is_in_cset()) {
808 log_error(gc, verify)("## inconsistent region attr type %s for humongous region %u", region_attr.get_type_str(), i);
809 _failures = true;
810 return true;
811 }
812 if (hr->is_continues_humongous() && region_attr.is_humongous()) {
813 log_error(gc, verify)("## inconsistent region attr type %s for continues humongous region %u", region_attr.get_type_str(), i);
814 _failures = true;
815 return true;
816 }
817 } else {
818 if (region_attr.is_humongous()) {
819 log_error(gc, verify)("## inconsistent region attr type %s for non-humongous region %u", region_attr.get_type_str(), i);
820 _failures = true;
821 return true;
822 }
823 if (hr->in_collection_set() != region_attr.is_in_cset()) {
824 log_error(gc, verify)("## in CSet %d / region attr type %s inconsistency for region %u",
825 hr->in_collection_set(), region_attr.get_type_str(), i);
826 _failures = true;
827 return true;
828 }
829 if (region_attr.is_in_cset()) {
830 if (hr->is_archive()) {
831 log_error(gc, verify)("## is_archive in collection set for region %u", i);
832 _failures = true;
833 return true;
834 }
835 if (hr->is_young() != (region_attr.is_young())) {
836 log_error(gc, verify)("## is_young %d / region attr type %s inconsistency for region %u",
837 hr->is_young(), region_attr.get_type_str(), i);
838 _failures = true;
839 return true;
840 }
841 if (hr->is_old() != (region_attr.is_old())) {
842 log_error(gc, verify)("## is_old %d / region attr type %s inconsistency for region %u",
843 hr->is_old(), region_attr.get_type_str(), i);
844 _failures = true;
845 return true;
846 }
847 }
848 }
849 return false;
850 }
851
852 bool failures() const { return _failures; }
853 };
854
855 bool G1HeapVerifier::check_region_attr_table() {
856 G1CheckRegionAttrTableClosure cl;
857 _g1h->_hrm->iterate(&cl);
858 return !cl.failures();
859 }
860 #endif // PRODUCT