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
VerifyRootsClosure(VerifyOption vo)58 VerifyRootsClosure(VerifyOption vo) :
59 _g1h(G1CollectedHeap::heap()),
60 _vo(vo),
61 _failures(false) { }
62
failures()63 bool failures() { return _failures; }
64
do_oop_work(T * p)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 " in region " HR_FORMAT,
72 p2i(p), p2i(obj), HR_FORMAT_PARAMS(_g1h->heap_region_containing(obj)));
73 ResourceMark rm;
74 LogStream ls(log.error());
75 obj->print_on(&ls);
76 _failures = true;
77 }
78 }
79 }
80
do_oop(oop * p)81 void do_oop(oop* p) { do_oop_work(p); }
do_oop(narrowOop * p)82 void do_oop(narrowOop* p) { do_oop_work(p); }
83 };
84
85 class G1VerifyCodeRootOopClosure: public OopClosure {
86 G1CollectedHeap* _g1h;
87 OopClosure* _root_cl;
88 nmethod* _nm;
89 VerifyOption _vo;
90 bool _failures;
91
do_oop_work(T * p)92 template <class T> void do_oop_work(T* p) {
93 // First verify that this root is live
94 _root_cl->do_oop(p);
95
96 if (!G1VerifyHeapRegionCodeRoots) {
97 // We're not verifying the code roots attached to heap region.
98 return;
99 }
100
101 // Don't check the code roots during marking verification in a full GC
102 if (_vo == VerifyOption_G1UseFullMarking) {
103 return;
104 }
105
106 // Now verify that the current nmethod (which contains p) is
107 // in the code root list of the heap region containing the
108 // object referenced by p.
109
110 T heap_oop = RawAccess<>::oop_load(p);
111 if (!CompressedOops::is_null(heap_oop)) {
112 oop obj = CompressedOops::decode_not_null(heap_oop);
113
114 // Now fetch the region containing the object
115 HeapRegion* hr = _g1h->heap_region_containing(obj);
116 HeapRegionRemSet* hrrs = hr->rem_set();
117 // Verify that the strong code root list for this region
118 // contains the nmethod
119 if (!hrrs->strong_code_roots_list_contains(_nm)) {
120 log_error(gc, verify)("Code root location " PTR_FORMAT " "
121 "from nmethod " PTR_FORMAT " not in strong "
122 "code roots for region [" PTR_FORMAT "," PTR_FORMAT ")",
123 p2i(p), p2i(_nm), p2i(hr->bottom()), p2i(hr->end()));
124 _failures = true;
125 }
126 }
127 }
128
129 public:
G1VerifyCodeRootOopClosure(G1CollectedHeap * g1h,OopClosure * root_cl,VerifyOption vo)130 G1VerifyCodeRootOopClosure(G1CollectedHeap* g1h, OopClosure* root_cl, VerifyOption vo):
131 _g1h(g1h), _root_cl(root_cl), _nm(NULL), _vo(vo), _failures(false) {}
132
do_oop(oop * p)133 void do_oop(oop* p) { do_oop_work(p); }
do_oop(narrowOop * p)134 void do_oop(narrowOop* p) { do_oop_work(p); }
135
set_nmethod(nmethod * nm)136 void set_nmethod(nmethod* nm) { _nm = nm; }
failures()137 bool failures() { return _failures; }
138 };
139
140 class G1VerifyCodeRootBlobClosure: public CodeBlobClosure {
141 G1VerifyCodeRootOopClosure* _oop_cl;
142
143 public:
G1VerifyCodeRootBlobClosure(G1VerifyCodeRootOopClosure * oop_cl)144 G1VerifyCodeRootBlobClosure(G1VerifyCodeRootOopClosure* oop_cl):
145 _oop_cl(oop_cl) {}
146
do_code_blob(CodeBlob * cb)147 void do_code_blob(CodeBlob* cb) {
148 nmethod* nm = cb->as_nmethod_or_null();
149 if (nm != NULL) {
150 _oop_cl->set_nmethod(nm);
151 nm->oops_do(_oop_cl);
152 }
153 }
154 };
155
156 class YoungRefCounterClosure : public OopClosure {
157 G1CollectedHeap* _g1h;
158 int _count;
159 public:
YoungRefCounterClosure(G1CollectedHeap * g1h)160 YoungRefCounterClosure(G1CollectedHeap* g1h) : _g1h(g1h), _count(0) {}
do_oop(oop * p)161 void do_oop(oop* p) { if (_g1h->is_in_young(*p)) { _count++; } }
do_oop(narrowOop * p)162 void do_oop(narrowOop* p) { ShouldNotReachHere(); }
163
count()164 int count() { return _count; }
reset_count()165 void reset_count() { _count = 0; };
166 };
167
168 class VerifyCLDClosure: public CLDClosure {
169 YoungRefCounterClosure _young_ref_counter_closure;
170 OopClosure *_oop_closure;
171 public:
VerifyCLDClosure(G1CollectedHeap * g1h,OopClosure * cl)172 VerifyCLDClosure(G1CollectedHeap* g1h, OopClosure* cl) : _young_ref_counter_closure(g1h), _oop_closure(cl) {}
do_cld(ClassLoaderData * cld)173 void do_cld(ClassLoaderData* cld) {
174 cld->oops_do(_oop_closure, ClassLoaderData::_claim_none);
175
176 _young_ref_counter_closure.reset_count();
177 cld->oops_do(&_young_ref_counter_closure, ClassLoaderData::_claim_none);
178 if (_young_ref_counter_closure.count() > 0) {
179 guarantee(cld->has_modified_oops(), "CLD " PTR_FORMAT ", has young %d refs but is not dirty.", p2i(cld), _young_ref_counter_closure.count());
180 }
181 }
182 };
183
184 class VerifyLivenessOopClosure: public BasicOopIterateClosure {
185 G1CollectedHeap* _g1h;
186 VerifyOption _vo;
187 public:
VerifyLivenessOopClosure(G1CollectedHeap * g1h,VerifyOption vo)188 VerifyLivenessOopClosure(G1CollectedHeap* g1h, VerifyOption vo):
189 _g1h(g1h), _vo(vo)
190 { }
do_oop(narrowOop * p)191 void do_oop(narrowOop *p) { do_oop_work(p); }
do_oop(oop * p)192 void do_oop( oop *p) { do_oop_work(p); }
193
do_oop_work(T * p)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 "Dead object referenced by a not dead object");
198 }
199 };
200
201 class VerifyObjsInRegionClosure: public ObjectClosure {
202 private:
203 G1CollectedHeap* _g1h;
204 size_t _live_bytes;
205 HeapRegion *_hr;
206 VerifyOption _vo;
207 public:
208 // _vo == UsePrevMarking -> use "prev" marking information,
209 // _vo == UseNextMarking -> use "next" marking information,
210 // _vo == UseFullMarking -> use "next" marking bitmap but no TAMS.
VerifyObjsInRegionClosure(HeapRegion * hr,VerifyOption vo)211 VerifyObjsInRegionClosure(HeapRegion *hr, VerifyOption vo)
212 : _live_bytes(0), _hr(hr), _vo(vo) {
213 _g1h = G1CollectedHeap::heap();
214 }
do_object(oop o)215 void do_object(oop o) {
216 VerifyLivenessOopClosure isLive(_g1h, _vo);
217 assert(o != NULL, "Huh?");
218 if (!_g1h->is_obj_dead_cond(o, _vo)) {
219 // If the object is alive according to the full gc mark,
220 // then verify that the marking information agrees.
221 // Note we can't verify the contra-positive of the
222 // above: if the object is dead (according to the mark
223 // word), it may not be marked, or may have been marked
224 // but has since became dead, or may have been allocated
225 // since the last marking.
226 if (_vo == VerifyOption_G1UseFullMarking) {
227 guarantee(!_g1h->is_obj_dead(o), "Full GC marking and concurrent mark mismatch");
228 }
229
230 o->oop_iterate(&isLive);
231 if (!_hr->obj_allocated_since_prev_marking(o)) {
232 size_t obj_size = o->size(); // Make sure we don't overflow
233 _live_bytes += (obj_size * HeapWordSize);
234 }
235 }
236 }
live_bytes()237 size_t live_bytes() { return _live_bytes; }
238 };
239
240 class VerifyArchiveOopClosure: public BasicOopIterateClosure {
241 HeapRegion* _hr;
242 public:
VerifyArchiveOopClosure(HeapRegion * hr)243 VerifyArchiveOopClosure(HeapRegion *hr) : _hr(hr) { }
do_oop(narrowOop * p)244 void do_oop(narrowOop *p) { do_oop_work(p); }
do_oop(oop * p)245 void do_oop( oop *p) { do_oop_work(p); }
246
do_oop_work(T * p)247 template <class T> void do_oop_work(T *p) {
248 oop obj = RawAccess<>::oop_load(p);
249
250 if (_hr->is_open_archive()) {
251 guarantee(obj == NULL || G1CollectedHeap::heap()->heap_region_containing(obj)->is_archive(),
252 "Archive object at " PTR_FORMAT " references a non-archive object at " PTR_FORMAT,
253 p2i(p), p2i(obj));
254 } else {
255 assert(_hr->is_closed_archive(), "should be closed archive region");
256 guarantee(obj == NULL || G1CollectedHeap::heap()->heap_region_containing(obj)->is_closed_archive(),
257 "Archive object at " PTR_FORMAT " references a non-archive object at " PTR_FORMAT,
258 p2i(p), p2i(obj));
259 }
260 }
261 };
262
263 class VerifyObjectInArchiveRegionClosure: public ObjectClosure {
264 HeapRegion* _hr;
265 public:
VerifyObjectInArchiveRegionClosure(HeapRegion * hr,bool verbose)266 VerifyObjectInArchiveRegionClosure(HeapRegion *hr, bool verbose)
267 : _hr(hr) { }
268 // Verify that all object pointers are to archive regions.
do_object(oop o)269 void do_object(oop o) {
270 VerifyArchiveOopClosure checkOop(_hr);
271 assert(o != NULL, "Should not be here for NULL oops");
272 o->oop_iterate(&checkOop);
273 }
274 };
275
276 // Should be only used at CDS dump time
277 class VerifyReadyForArchivingRegionClosure : public HeapRegionClosure {
278 bool _seen_free;
279 bool _has_holes;
280 bool _has_unexpected_holes;
281 bool _has_humongous;
282 public:
has_holes()283 bool has_holes() {return _has_holes;}
has_unexpected_holes()284 bool has_unexpected_holes() {return _has_unexpected_holes;}
has_humongous()285 bool has_humongous() {return _has_humongous;}
286
VerifyReadyForArchivingRegionClosure()287 VerifyReadyForArchivingRegionClosure() : HeapRegionClosure() {
288 _seen_free = false;
289 _has_holes = false;
290 _has_unexpected_holes = false;
291 _has_humongous = false;
292 }
do_heap_region(HeapRegion * hr)293 virtual bool do_heap_region(HeapRegion* hr) {
294 const char* hole = "";
295
296 if (hr->is_free()) {
297 _seen_free = true;
298 } else {
299 if (_seen_free) {
300 _has_holes = true;
301 if (hr->is_humongous()) {
302 hole = " hole";
303 } else {
304 _has_unexpected_holes = true;
305 hole = " hole **** unexpected ****";
306 }
307 }
308 }
309 if (hr->is_humongous()) {
310 _has_humongous = true;
311 }
312 log_info(gc, region, cds)("HeapRegion " INTPTR_FORMAT " %s%s", p2i(hr->bottom()), hr->get_type_str(), hole);
313 return false;
314 }
315 };
316
317 // We want all used regions to be moved to the bottom-end of the heap, so we have
318 // a contiguous range of free regions at the top end of the heap. This way, we can
319 // avoid fragmentation while allocating the archive regions.
320 //
321 // Before calling this, a full GC should have been executed with a single worker thread,
322 // so that no old regions would be moved to the middle of the heap.
verify_ready_for_archiving()323 void G1HeapVerifier::verify_ready_for_archiving() {
324 VerifyReadyForArchivingRegionClosure cl;
325 G1CollectedHeap::heap()->heap_region_iterate(&cl);
326 if (cl.has_holes()) {
327 log_warning(gc, verify)("All free regions should be at the top end of the heap, but"
328 " we found holes. This is probably caused by (unmovable) humongous"
329 " allocations or active GCLocker, and may lead to fragmentation while"
330 " writing archive heap memory regions.");
331 }
332 if (cl.has_humongous()) {
333 log_warning(gc, verify)("(Unmovable) humongous regions have been found and"
334 " may lead to fragmentation while"
335 " writing archive heap memory regions.");
336 }
337 }
338
339 class VerifyArchivePointerRegionClosure: public HeapRegionClosure {
do_heap_region(HeapRegion * r)340 virtual bool do_heap_region(HeapRegion* r) {
341 if (r->is_archive()) {
342 VerifyObjectInArchiveRegionClosure verify_oop_pointers(r, false);
343 r->object_iterate(&verify_oop_pointers);
344 }
345 return false;
346 }
347 };
348
verify_archive_regions()349 void G1HeapVerifier::verify_archive_regions() {
350 G1CollectedHeap* g1h = G1CollectedHeap::heap();
351 VerifyArchivePointerRegionClosure cl;
352 g1h->heap_region_iterate(&cl);
353 }
354
355 class VerifyRegionClosure: public HeapRegionClosure {
356 private:
357 bool _par;
358 VerifyOption _vo;
359 bool _failures;
360 public:
361 // _vo == UsePrevMarking -> use "prev" marking information,
362 // _vo == UseNextMarking -> use "next" marking information,
363 // _vo == UseFullMarking -> use "next" marking bitmap but no TAMS
VerifyRegionClosure(bool par,VerifyOption vo)364 VerifyRegionClosure(bool par, VerifyOption vo)
365 : _par(par),
366 _vo(vo),
367 _failures(false) {}
368
failures()369 bool failures() {
370 return _failures;
371 }
372
do_heap_region(HeapRegion * r)373 bool do_heap_region(HeapRegion* r) {
374 guarantee(!r->has_index_in_opt_cset(), "Region %u still has opt collection set index %u", r->hrm_index(), r->index_in_opt_cset());
375 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());
376 // Humongous and old regions regions might be of any state, so can't check here.
377 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());
378 // Verify that the continues humongous regions' remembered set state matches the
379 // one from the starts humongous region.
380 if (r->is_continues_humongous()) {
381 if (r->rem_set()->get_state_str() != r->humongous_start_region()->rem_set()->get_state_str()) {
382 log_error(gc, verify)("Remset states differ: Region %u (%s) remset %s with starts region %u (%s) remset %s",
383 r->hrm_index(),
384 r->get_short_type_str(),
385 r->rem_set()->get_state_str(),
386 r->humongous_start_region()->hrm_index(),
387 r->humongous_start_region()->get_short_type_str(),
388 r->humongous_start_region()->rem_set()->get_state_str());
389 _failures = true;
390 }
391 }
392 // For archive regions, verify there are no heap pointers to
393 // non-pinned regions. For all others, verify liveness info.
394 if (r->is_closed_archive()) {
395 VerifyObjectInArchiveRegionClosure verify_oop_pointers(r, false);
396 r->object_iterate(&verify_oop_pointers);
397 return true;
398 } else if (r->is_open_archive()) {
399 VerifyObjsInRegionClosure verify_open_archive_oop(r, _vo);
400 r->object_iterate(&verify_open_archive_oop);
401 return true;
402 } else if (!r->is_continues_humongous()) {
403 bool failures = false;
404 r->verify(_vo, &failures);
405 if (failures) {
406 _failures = true;
407 } else if (!r->is_starts_humongous()) {
408 VerifyObjsInRegionClosure not_dead_yet_cl(r, _vo);
409 r->object_iterate(¬_dead_yet_cl);
410 if (_vo != VerifyOption_G1UseNextMarking) {
411 if (r->max_live_bytes() < not_dead_yet_cl.live_bytes()) {
412 log_error(gc, verify)("[" PTR_FORMAT "," PTR_FORMAT "] max_live_bytes " SIZE_FORMAT " < calculated " SIZE_FORMAT,
413 p2i(r->bottom()), p2i(r->end()), r->max_live_bytes(), not_dead_yet_cl.live_bytes());
414 _failures = true;
415 }
416 } else {
417 // When vo == UseNextMarking we cannot currently do a sanity
418 // check on the live bytes as the calculation has not been
419 // finalized yet.
420 }
421 }
422 }
423 return false; // stop the region iteration if we hit a failure
424 }
425 };
426
427 // This is the task used for parallel verification of the heap regions
428
429 class G1ParVerifyTask: public AbstractGangTask {
430 private:
431 G1CollectedHeap* _g1h;
432 VerifyOption _vo;
433 bool _failures;
434 HeapRegionClaimer _hrclaimer;
435
436 public:
437 // _vo == UsePrevMarking -> use "prev" marking information,
438 // _vo == UseNextMarking -> use "next" marking information,
439 // _vo == UseFullMarking -> use "next" marking bitmap but no TAMS
G1ParVerifyTask(G1CollectedHeap * g1h,VerifyOption vo)440 G1ParVerifyTask(G1CollectedHeap* g1h, VerifyOption vo) :
441 AbstractGangTask("Parallel verify task"),
442 _g1h(g1h),
443 _vo(vo),
444 _failures(false),
445 _hrclaimer(g1h->workers()->active_workers()) {}
446
failures()447 bool failures() {
448 return _failures;
449 }
450
work(uint worker_id)451 void work(uint worker_id) {
452 VerifyRegionClosure blk(true, _vo);
453 _g1h->heap_region_par_iterate_from_worker_offset(&blk, &_hrclaimer, worker_id);
454 if (blk.failures()) {
455 _failures = true;
456 }
457 }
458 };
459
enable_verification_type(G1VerifyType type)460 void G1HeapVerifier::enable_verification_type(G1VerifyType type) {
461 // First enable will clear _enabled_verification_types.
462 if (_enabled_verification_types == G1VerifyAll) {
463 _enabled_verification_types = type;
464 } else {
465 _enabled_verification_types |= type;
466 }
467 }
468
should_verify(G1VerifyType type)469 bool G1HeapVerifier::should_verify(G1VerifyType type) {
470 return (_enabled_verification_types & type) == type;
471 }
472
verify(VerifyOption vo)473 void G1HeapVerifier::verify(VerifyOption vo) {
474 assert_at_safepoint_on_vm_thread();
475 assert(Heap_lock->is_locked(), "heap must be locked");
476
477 log_debug(gc, verify)("Roots");
478 VerifyRootsClosure rootsCl(vo);
479 VerifyCLDClosure cldCl(_g1h, &rootsCl);
480
481 // We apply the relevant closures to all the oops in the
482 // system dictionary, class loader data graph, the string table
483 // and the nmethods in the code cache.
484 G1VerifyCodeRootOopClosure codeRootsCl(_g1h, &rootsCl, vo);
485 G1VerifyCodeRootBlobClosure blobsCl(&codeRootsCl);
486
487 {
488 G1RootProcessor root_processor(_g1h, 1);
489 root_processor.process_all_roots(&rootsCl, &cldCl, &blobsCl);
490 }
491
492 bool failures = rootsCl.failures() || codeRootsCl.failures();
493
494 if (!_g1h->policy()->collector_state()->in_full_gc()) {
495 // If we're verifying during a full GC then the region sets
496 // will have been torn down at the start of the GC. Therefore
497 // verifying the region sets will fail. So we only verify
498 // the region sets when not in a full GC.
499 log_debug(gc, verify)("HeapRegionSets");
500 verify_region_sets();
501 }
502
503 log_debug(gc, verify)("HeapRegions");
504 if (GCParallelVerificationEnabled && ParallelGCThreads > 1) {
505
506 G1ParVerifyTask task(_g1h, vo);
507 _g1h->workers()->run_task(&task);
508 if (task.failures()) {
509 failures = true;
510 }
511
512 } else {
513 VerifyRegionClosure blk(false, vo);
514 _g1h->heap_region_iterate(&blk);
515 if (blk.failures()) {
516 failures = true;
517 }
518 }
519
520 if (G1StringDedup::is_enabled()) {
521 log_debug(gc, verify)("StrDedup");
522 G1StringDedup::verify();
523 }
524
525 if (failures) {
526 log_error(gc, verify)("Heap after failed verification (kind %d):", vo);
527 // It helps to have the per-region information in the output to
528 // help us track down what went wrong. This is why we call
529 // print_extended_on() instead of print_on().
530 Log(gc, verify) log;
531 ResourceMark rm;
532 LogStream ls(log.error());
533 _g1h->print_extended_on(&ls);
534 }
535 guarantee(!failures, "there should not have been any failures");
536 }
537
538 // Heap region set verification
539
540 class VerifyRegionListsClosure : public HeapRegionClosure {
541 private:
542 HeapRegionSet* _old_set;
543 HeapRegionSet* _archive_set;
544 HeapRegionSet* _humongous_set;
545 HeapRegionManager* _hrm;
546
547 public:
548 uint _old_count;
549 uint _archive_count;
550 uint _humongous_count;
551 uint _free_count;
552
VerifyRegionListsClosure(HeapRegionSet * old_set,HeapRegionSet * archive_set,HeapRegionSet * humongous_set,HeapRegionManager * hrm)553 VerifyRegionListsClosure(HeapRegionSet* old_set,
554 HeapRegionSet* archive_set,
555 HeapRegionSet* humongous_set,
556 HeapRegionManager* hrm) :
557 _old_set(old_set), _archive_set(archive_set), _humongous_set(humongous_set), _hrm(hrm),
558 _old_count(), _archive_count(), _humongous_count(), _free_count(){ }
559
do_heap_region(HeapRegion * hr)560 bool do_heap_region(HeapRegion* hr) {
561 if (hr->is_young()) {
562 // TODO
563 } else if (hr->is_humongous()) {
564 assert(hr->containing_set() == _humongous_set, "Heap region %u is humongous but not in humongous set.", hr->hrm_index());
565 _humongous_count++;
566 } else if (hr->is_empty()) {
567 assert(_hrm->is_free(hr), "Heap region %u is empty but not on the free list.", hr->hrm_index());
568 _free_count++;
569 } else if (hr->is_archive()) {
570 assert(hr->containing_set() == _archive_set, "Heap region %u is archive but not in the archive set.", hr->hrm_index());
571 _archive_count++;
572 } else if (hr->is_old()) {
573 assert(hr->containing_set() == _old_set, "Heap region %u is old but not in the old set.", hr->hrm_index());
574 _old_count++;
575 } else {
576 // There are no other valid region types. Check for one invalid
577 // one we can identify: pinned without old or humongous set.
578 assert(!hr->is_pinned(), "Heap region %u is pinned but not old (archive) or humongous.", hr->hrm_index());
579 ShouldNotReachHere();
580 }
581 return false;
582 }
583
verify_counts(HeapRegionSet * old_set,HeapRegionSet * archive_set,HeapRegionSet * humongous_set,HeapRegionManager * free_list)584 void verify_counts(HeapRegionSet* old_set, HeapRegionSet* archive_set, HeapRegionSet* humongous_set, HeapRegionManager* free_list) {
585 guarantee(old_set->length() == _old_count, "Old set count mismatch. Expected %u, actual %u.", old_set->length(), _old_count);
586 guarantee(archive_set->length() == _archive_count, "Archive set count mismatch. Expected %u, actual %u.", archive_set->length(), _archive_count);
587 guarantee(humongous_set->length() == _humongous_count, "Hum set count mismatch. Expected %u, actual %u.", humongous_set->length(), _humongous_count);
588 guarantee(free_list->num_free_regions() == _free_count, "Free list count mismatch. Expected %u, actual %u.", free_list->num_free_regions(), _free_count);
589 }
590 };
591
verify_region_sets()592 void G1HeapVerifier::verify_region_sets() {
593 assert_heap_locked_or_at_safepoint(true /* should_be_vm_thread */);
594
595 // First, check the explicit lists.
596 _g1h->_hrm.verify();
597
598 // Finally, make sure that the region accounting in the lists is
599 // consistent with what we see in the heap.
600
601 VerifyRegionListsClosure cl(&_g1h->_old_set, &_g1h->_archive_set, &_g1h->_humongous_set, &_g1h->_hrm);
602 _g1h->heap_region_iterate(&cl);
603 cl.verify_counts(&_g1h->_old_set, &_g1h->_archive_set, &_g1h->_humongous_set, &_g1h->_hrm);
604 }
605
prepare_for_verify()606 void G1HeapVerifier::prepare_for_verify() {
607 if (SafepointSynchronize::is_at_safepoint() || ! UseTLAB) {
608 _g1h->ensure_parsability(false);
609 }
610 }
611
verify(G1VerifyType type,VerifyOption vo,const char * msg)612 double G1HeapVerifier::verify(G1VerifyType type, VerifyOption vo, const char* msg) {
613 double verify_time_ms = 0.0;
614
615 if (should_verify(type) && _g1h->total_collections() >= VerifyGCStartAt) {
616 double verify_start = os::elapsedTime();
617 prepare_for_verify();
618 Universe::verify(vo, msg);
619 verify_time_ms = (os::elapsedTime() - verify_start) * 1000;
620 }
621
622 return verify_time_ms;
623 }
624
verify_before_gc(G1VerifyType type)625 void G1HeapVerifier::verify_before_gc(G1VerifyType type) {
626 if (VerifyBeforeGC) {
627 double verify_time_ms = verify(type, VerifyOption_G1UsePrevMarking, "Before GC");
628 _g1h->phase_times()->record_verify_before_time_ms(verify_time_ms);
629 }
630 }
631
verify_after_gc(G1VerifyType type)632 void G1HeapVerifier::verify_after_gc(G1VerifyType type) {
633 if (VerifyAfterGC) {
634 double verify_time_ms = verify(type, VerifyOption_G1UsePrevMarking, "After GC");
635 _g1h->phase_times()->record_verify_after_time_ms(verify_time_ms);
636 }
637 }
638
639
640 #ifndef PRODUCT
641 class G1VerifyCardTableCleanup: public HeapRegionClosure {
642 G1HeapVerifier* _verifier;
643 public:
G1VerifyCardTableCleanup(G1HeapVerifier * verifier)644 G1VerifyCardTableCleanup(G1HeapVerifier* verifier)
645 : _verifier(verifier) { }
do_heap_region(HeapRegion * r)646 virtual bool do_heap_region(HeapRegion* r) {
647 if (r->is_survivor()) {
648 _verifier->verify_dirty_region(r);
649 } else {
650 _verifier->verify_not_dirty_region(r);
651 }
652 return false;
653 }
654 };
655
verify_card_table_cleanup()656 void G1HeapVerifier::verify_card_table_cleanup() {
657 if (G1VerifyCTCleanup || VerifyAfterGC) {
658 G1VerifyCardTableCleanup cleanup_verifier(this);
659 _g1h->heap_region_iterate(&cleanup_verifier);
660 }
661 }
662
verify_not_dirty_region(HeapRegion * hr)663 void G1HeapVerifier::verify_not_dirty_region(HeapRegion* hr) {
664 // All of the region should be clean.
665 G1CardTable* ct = _g1h->card_table();
666 MemRegion mr(hr->bottom(), hr->end());
667 ct->verify_not_dirty_region(mr);
668 }
669
verify_dirty_region(HeapRegion * hr)670 void G1HeapVerifier::verify_dirty_region(HeapRegion* hr) {
671 // We cannot guarantee that [bottom(),end()] is dirty. Threads
672 // dirty allocated blocks as they allocate them. The thread that
673 // retires each region and replaces it with a new one will do a
674 // maximal allocation to fill in [pre_dummy_top(),end()] but will
675 // not dirty that area (one less thing to have to do while holding
676 // a lock). So we can only verify that [bottom(),pre_dummy_top()]
677 // is dirty.
678 G1CardTable* ct = _g1h->card_table();
679 MemRegion mr(hr->bottom(), hr->pre_dummy_top());
680 if (hr->is_young()) {
681 ct->verify_g1_young_region(mr);
682 } else {
683 ct->verify_dirty_region(mr);
684 }
685 }
686
687 class G1VerifyDirtyYoungListClosure : public HeapRegionClosure {
688 private:
689 G1HeapVerifier* _verifier;
690 public:
G1VerifyDirtyYoungListClosure(G1HeapVerifier * verifier)691 G1VerifyDirtyYoungListClosure(G1HeapVerifier* verifier) : HeapRegionClosure(), _verifier(verifier) { }
do_heap_region(HeapRegion * r)692 virtual bool do_heap_region(HeapRegion* r) {
693 _verifier->verify_dirty_region(r);
694 return false;
695 }
696 };
697
verify_dirty_young_regions()698 void G1HeapVerifier::verify_dirty_young_regions() {
699 G1VerifyDirtyYoungListClosure cl(this);
700 _g1h->collection_set()->iterate(&cl);
701 }
702
verify_no_bits_over_tams(const char * bitmap_name,const G1CMBitMap * const bitmap,HeapWord * tams,HeapWord * end)703 bool G1HeapVerifier::verify_no_bits_over_tams(const char* bitmap_name, const G1CMBitMap* const bitmap,
704 HeapWord* tams, HeapWord* end) {
705 guarantee(tams <= end,
706 "tams: " PTR_FORMAT " end: " PTR_FORMAT, p2i(tams), p2i(end));
707 HeapWord* result = bitmap->get_next_marked_addr(tams, end);
708 if (result < end) {
709 log_error(gc, verify)("## wrong marked address on %s bitmap: " PTR_FORMAT, bitmap_name, p2i(result));
710 log_error(gc, verify)("## %s tams: " PTR_FORMAT " end: " PTR_FORMAT, bitmap_name, p2i(tams), p2i(end));
711 return false;
712 }
713 return true;
714 }
715
verify_bitmaps(const char * caller,HeapRegion * hr)716 bool G1HeapVerifier::verify_bitmaps(const char* caller, HeapRegion* hr) {
717 const G1CMBitMap* const prev_bitmap = _g1h->concurrent_mark()->prev_mark_bitmap();
718 const G1CMBitMap* const next_bitmap = _g1h->concurrent_mark()->next_mark_bitmap();
719
720 HeapWord* ptams = hr->prev_top_at_mark_start();
721 HeapWord* ntams = hr->next_top_at_mark_start();
722 HeapWord* end = hr->end();
723
724 bool res_p = verify_no_bits_over_tams("prev", prev_bitmap, ptams, end);
725
726 bool res_n = true;
727 // We cannot verify the next bitmap while we are about to clear it.
728 if (!_g1h->collector_state()->clearing_next_bitmap()) {
729 res_n = verify_no_bits_over_tams("next", next_bitmap, ntams, end);
730 }
731 if (!res_p || !res_n) {
732 log_error(gc, verify)("#### Bitmap verification failed for " HR_FORMAT, HR_FORMAT_PARAMS(hr));
733 log_error(gc, verify)("#### Caller: %s", caller);
734 return false;
735 }
736 return true;
737 }
738
check_bitmaps(const char * caller,HeapRegion * hr)739 void G1HeapVerifier::check_bitmaps(const char* caller, HeapRegion* hr) {
740 if (!G1VerifyBitmaps) {
741 return;
742 }
743
744 guarantee(verify_bitmaps(caller, hr), "bitmap verification");
745 }
746
747 class G1VerifyBitmapClosure : public HeapRegionClosure {
748 private:
749 const char* _caller;
750 G1HeapVerifier* _verifier;
751 bool _failures;
752
753 public:
G1VerifyBitmapClosure(const char * caller,G1HeapVerifier * verifier)754 G1VerifyBitmapClosure(const char* caller, G1HeapVerifier* verifier) :
755 _caller(caller), _verifier(verifier), _failures(false) { }
756
failures()757 bool failures() { return _failures; }
758
do_heap_region(HeapRegion * hr)759 virtual bool do_heap_region(HeapRegion* hr) {
760 bool result = _verifier->verify_bitmaps(_caller, hr);
761 if (!result) {
762 _failures = true;
763 }
764 return false;
765 }
766 };
767
check_bitmaps(const char * caller)768 void G1HeapVerifier::check_bitmaps(const char* caller) {
769 if (!G1VerifyBitmaps) {
770 return;
771 }
772
773 G1VerifyBitmapClosure cl(caller, this);
774 _g1h->heap_region_iterate(&cl);
775 guarantee(!cl.failures(), "bitmap verification");
776 }
777
778 class G1CheckRegionAttrTableClosure : public HeapRegionClosure {
779 private:
780 bool _failures;
781
782 public:
G1CheckRegionAttrTableClosure()783 G1CheckRegionAttrTableClosure() : HeapRegionClosure(), _failures(false) { }
784
do_heap_region(HeapRegion * hr)785 virtual bool do_heap_region(HeapRegion* hr) {
786 uint i = hr->hrm_index();
787 G1HeapRegionAttr region_attr = (G1HeapRegionAttr) G1CollectedHeap::heap()->_region_attr.get_by_index(i);
788 if (hr->is_humongous()) {
789 if (hr->in_collection_set()) {
790 log_error(gc, verify)("## humongous region %u in CSet", i);
791 _failures = true;
792 return true;
793 }
794 if (region_attr.is_in_cset()) {
795 log_error(gc, verify)("## inconsistent region attr type %s for humongous region %u", region_attr.get_type_str(), i);
796 _failures = true;
797 return true;
798 }
799 if (hr->is_continues_humongous() && region_attr.is_humongous()) {
800 log_error(gc, verify)("## inconsistent region attr type %s for continues humongous region %u", region_attr.get_type_str(), i);
801 _failures = true;
802 return true;
803 }
804 } else {
805 if (region_attr.is_humongous()) {
806 log_error(gc, verify)("## inconsistent region attr type %s for non-humongous region %u", region_attr.get_type_str(), i);
807 _failures = true;
808 return true;
809 }
810 if (hr->in_collection_set() != region_attr.is_in_cset()) {
811 log_error(gc, verify)("## in CSet %d / region attr type %s inconsistency for region %u",
812 hr->in_collection_set(), region_attr.get_type_str(), i);
813 _failures = true;
814 return true;
815 }
816 if (region_attr.is_in_cset()) {
817 if (hr->is_archive()) {
818 log_error(gc, verify)("## is_archive in collection set for region %u", i);
819 _failures = true;
820 return true;
821 }
822 if (hr->is_young() != (region_attr.is_young())) {
823 log_error(gc, verify)("## is_young %d / region attr type %s inconsistency for region %u",
824 hr->is_young(), region_attr.get_type_str(), i);
825 _failures = true;
826 return true;
827 }
828 if (hr->is_old() != (region_attr.is_old())) {
829 log_error(gc, verify)("## is_old %d / region attr type %s inconsistency for region %u",
830 hr->is_old(), region_attr.get_type_str(), i);
831 _failures = true;
832 return true;
833 }
834 }
835 }
836 return false;
837 }
838
failures() const839 bool failures() const { return _failures; }
840 };
841
check_region_attr_table()842 bool G1HeapVerifier::check_region_attr_table() {
843 G1CheckRegionAttrTableClosure cl;
844 _g1h->_hrm.iterate(&cl);
845 return !cl.failures();
846 }
847 #endif // PRODUCT
848