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 "gc/shared/tlab_globals.hpp"
27 #include "gc/shenandoah/shenandoahAsserts.hpp"
28 #include "gc/shenandoah/shenandoahForwarding.inline.hpp"
29 #include "gc/shenandoah/shenandoahPhaseTimings.hpp"
30 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
31 #include "gc/shenandoah/shenandoahHeapRegion.inline.hpp"
32 #include "gc/shenandoah/shenandoahRootProcessor.hpp"
33 #include "gc/shenandoah/shenandoahTaskqueue.inline.hpp"
34 #include "gc/shenandoah/shenandoahUtils.hpp"
35 #include "gc/shenandoah/shenandoahVerifier.hpp"
36 #include "memory/allocation.hpp"
37 #include "memory/iterator.inline.hpp"
38 #include "memory/resourceArea.hpp"
39 #include "oops/compressedOops.inline.hpp"
40 #include "runtime/atomic.hpp"
41 #include "runtime/orderAccess.hpp"
42 #include "runtime/threads.hpp"
43 #include "utilities/align.hpp"
44
45 // Avoid name collision on verify_oop (defined in macroAssembler_arm.hpp)
46 #ifdef verify_oop
47 #undef verify_oop
48 #endif
49
50 static bool is_instance_ref_klass(Klass* k) {
51 return k->is_instance_klass() && InstanceKlass::cast(k)->reference_type() != REF_NONE;
52 }
53
54 class ShenandoahIgnoreReferenceDiscoverer : public ReferenceDiscoverer {
55 public:
56 virtual bool discover_reference(oop obj, ReferenceType type) {
57 return true;
58 }
59 };
60
61 class ShenandoahVerifyOopClosure : public BasicOopIterateClosure {
62 private:
63 const char* _phase;
64 ShenandoahVerifier::VerifyOptions _options;
65 ShenandoahVerifierStack* _stack;
66 ShenandoahHeap* _heap;
67 MarkBitMap* _map;
68 ShenandoahLivenessData* _ld;
69 void* _interior_loc;
70 oop _loc;
71
72 public:
73 ShenandoahVerifyOopClosure(ShenandoahVerifierStack* stack, MarkBitMap* map, ShenandoahLivenessData* ld,
74 const char* phase, ShenandoahVerifier::VerifyOptions options) :
75 _phase(phase),
76 _options(options),
77 _stack(stack),
78 _heap(ShenandoahHeap::heap()),
79 _map(map),
80 _ld(ld),
81 _interior_loc(NULL),
82 _loc(NULL) {
83 if (options._verify_marked == ShenandoahVerifier::_verify_marked_complete_except_references ||
84 options._verify_marked == ShenandoahVerifier::_verify_marked_disable) {
85 set_ref_discoverer_internal(new ShenandoahIgnoreReferenceDiscoverer());
86 }
87 }
88
89 private:
90 void check(ShenandoahAsserts::SafeLevel level, oop obj, bool test, const char* label) {
91 if (!test) {
92 ShenandoahAsserts::print_failure(level, obj, _interior_loc, _loc, _phase, label, __FILE__, __LINE__);
93 }
94 }
95
96 template <class T>
97 void do_oop_work(T* p) {
98 T o = RawAccess<>::oop_load(p);
99 if (!CompressedOops::is_null(o)) {
100 oop obj = CompressedOops::decode_not_null(o);
101 if (is_instance_ref_klass(obj->klass())) {
102 obj = ShenandoahForwarding::get_forwardee(obj);
103 }
104 // Single threaded verification can use faster non-atomic stack and bitmap
105 // methods.
106 //
107 // For performance reasons, only fully verify non-marked field values.
108 // We are here when the host object for *p is already marked.
109
110 if (_map->par_mark(obj)) {
111 verify_oop_at(p, obj);
112 _stack->push(ShenandoahVerifierTask(obj));
113 }
114 }
115 }
116
117 void verify_oop(oop obj) {
118 // Perform consistency checks with gradually decreasing safety level. This guarantees
119 // that failure report would not try to touch something that was not yet verified to be
120 // safe to process.
121
122 check(ShenandoahAsserts::_safe_unknown, obj, _heap->is_in(obj),
123 "oop must be in heap");
124 check(ShenandoahAsserts::_safe_unknown, obj, is_object_aligned(obj),
125 "oop must be aligned");
126
127 ShenandoahHeapRegion *obj_reg = _heap->heap_region_containing(obj);
128 Klass* obj_klass = obj->klass_or_null();
129
130 // Verify that obj is not in dead space:
131 {
132 // Do this before touching obj->size()
133 check(ShenandoahAsserts::_safe_unknown, obj, obj_klass != NULL,
134 "Object klass pointer should not be NULL");
135 check(ShenandoahAsserts::_safe_unknown, obj, Metaspace::contains(obj_klass),
136 "Object klass pointer must go to metaspace");
137
138 HeapWord *obj_addr = cast_from_oop<HeapWord*>(obj);
139 check(ShenandoahAsserts::_safe_unknown, obj, obj_addr < obj_reg->top(),
140 "Object start should be within the region");
141
142 if (!obj_reg->is_humongous()) {
143 check(ShenandoahAsserts::_safe_unknown, obj, (obj_addr + obj->size()) <= obj_reg->top(),
144 "Object end should be within the region");
145 } else {
146 size_t humongous_start = obj_reg->index();
147 size_t humongous_end = humongous_start + (obj->size() >> ShenandoahHeapRegion::region_size_words_shift());
148 for (size_t idx = humongous_start + 1; idx < humongous_end; idx++) {
149 check(ShenandoahAsserts::_safe_unknown, obj, _heap->get_region(idx)->is_humongous_continuation(),
150 "Humongous object is in continuation that fits it");
151 }
152 }
153
154 // ------------ obj is safe at this point --------------
155
156 check(ShenandoahAsserts::_safe_oop, obj, obj_reg->is_active(),
157 "Object should be in active region");
158
159 switch (_options._verify_liveness) {
160 case ShenandoahVerifier::_verify_liveness_disable:
161 // skip
162 break;
163 case ShenandoahVerifier::_verify_liveness_complete:
164 Atomic::add(&_ld[obj_reg->index()], (uint) obj->size(), memory_order_relaxed);
165 // fallthrough for fast failure for un-live regions:
166 case ShenandoahVerifier::_verify_liveness_conservative:
167 check(ShenandoahAsserts::_safe_oop, obj, obj_reg->has_live(),
168 "Object must belong to region with live data");
169 break;
170 default:
171 assert(false, "Unhandled liveness verification");
172 }
173 }
174
175 oop fwd = ShenandoahForwarding::get_forwardee_raw_unchecked(obj);
176
177 ShenandoahHeapRegion* fwd_reg = NULL;
178
179 if (obj != fwd) {
180 check(ShenandoahAsserts::_safe_oop, obj, _heap->is_in(fwd),
181 "Forwardee must be in heap");
182 check(ShenandoahAsserts::_safe_oop, obj, !CompressedOops::is_null(fwd),
183 "Forwardee is set");
184 check(ShenandoahAsserts::_safe_oop, obj, is_object_aligned(fwd),
185 "Forwardee must be aligned");
186
187 // Do this before touching fwd->size()
188 Klass* fwd_klass = fwd->klass_or_null();
189 check(ShenandoahAsserts::_safe_oop, obj, fwd_klass != NULL,
190 "Forwardee klass pointer should not be NULL");
191 check(ShenandoahAsserts::_safe_oop, obj, Metaspace::contains(fwd_klass),
192 "Forwardee klass pointer must go to metaspace");
193 check(ShenandoahAsserts::_safe_oop, obj, obj_klass == fwd_klass,
194 "Forwardee klass pointer must go to metaspace");
195
196 fwd_reg = _heap->heap_region_containing(fwd);
197
198 // Verify that forwardee is not in the dead space:
199 check(ShenandoahAsserts::_safe_oop, obj, !fwd_reg->is_humongous(),
200 "Should have no humongous forwardees");
201
202 HeapWord *fwd_addr = cast_from_oop<HeapWord *>(fwd);
203 check(ShenandoahAsserts::_safe_oop, obj, fwd_addr < fwd_reg->top(),
204 "Forwardee start should be within the region");
205 check(ShenandoahAsserts::_safe_oop, obj, (fwd_addr + fwd->size()) <= fwd_reg->top(),
206 "Forwardee end should be within the region");
207
208 oop fwd2 = ShenandoahForwarding::get_forwardee_raw_unchecked(fwd);
209 check(ShenandoahAsserts::_safe_oop, obj, (fwd == fwd2),
210 "Double forwarding");
211 } else {
212 fwd_reg = obj_reg;
213 }
214
215 // ------------ obj and fwd are safe at this point --------------
216
217 switch (_options._verify_marked) {
218 case ShenandoahVerifier::_verify_marked_disable:
219 // skip
220 break;
221 case ShenandoahVerifier::_verify_marked_incomplete:
222 check(ShenandoahAsserts::_safe_all, obj, _heap->marking_context()->is_marked(obj),
223 "Must be marked in incomplete bitmap");
224 break;
225 case ShenandoahVerifier::_verify_marked_complete:
226 check(ShenandoahAsserts::_safe_all, obj, _heap->complete_marking_context()->is_marked(obj),
227 "Must be marked in complete bitmap");
228 break;
229 case ShenandoahVerifier::_verify_marked_complete_except_references:
230 check(ShenandoahAsserts::_safe_all, obj, _heap->complete_marking_context()->is_marked(obj),
231 "Must be marked in complete bitmap, except j.l.r.Reference referents");
232 break;
233 default:
234 assert(false, "Unhandled mark verification");
235 }
236
237 switch (_options._verify_forwarded) {
238 case ShenandoahVerifier::_verify_forwarded_disable:
239 // skip
240 break;
241 case ShenandoahVerifier::_verify_forwarded_none: {
242 check(ShenandoahAsserts::_safe_all, obj, (obj == fwd),
243 "Should not be forwarded");
244 break;
245 }
246 case ShenandoahVerifier::_verify_forwarded_allow: {
247 if (obj != fwd) {
248 check(ShenandoahAsserts::_safe_all, obj, obj_reg != fwd_reg,
249 "Forwardee should be in another region");
250 }
296 void verify_oop_standalone(oop obj) {
297 _interior_loc = NULL;
298 verify_oop(obj);
299 _interior_loc = NULL;
300 }
301
302 /**
303 * Verify oop fields from this object.
304 * @param obj host object for verified fields
305 */
306 void verify_oops_from(oop obj) {
307 _loc = obj;
308 obj->oop_iterate(this);
309 _loc = NULL;
310 }
311
312 virtual void do_oop(oop* p) { do_oop_work(p); }
313 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
314 };
315
316 class ShenandoahCalculateRegionStatsClosure : public ShenandoahHeapRegionClosure {
317 private:
318 size_t _used, _committed, _garbage;
319 public:
320 ShenandoahCalculateRegionStatsClosure() : _used(0), _committed(0), _garbage(0) {};
321
322 void heap_region_do(ShenandoahHeapRegion* r) {
323 _used += r->used();
324 _garbage += r->garbage();
325 _committed += r->is_committed() ? ShenandoahHeapRegion::region_size_bytes() : 0;
326 }
327
328 size_t used() { return _used; }
329 size_t committed() { return _committed; }
330 size_t garbage() { return _garbage; }
331 };
332
333 class ShenandoahVerifyHeapRegionClosure : public ShenandoahHeapRegionClosure {
334 private:
335 ShenandoahHeap* _heap;
336 const char* _phase;
337 ShenandoahVerifier::VerifyRegions _regions;
338 public:
339 ShenandoahVerifyHeapRegionClosure(const char* phase, ShenandoahVerifier::VerifyRegions regions) :
340 _heap(ShenandoahHeap::heap()),
341 _phase(phase),
342 _regions(regions) {};
343
344 void print_failure(ShenandoahHeapRegion* r, const char* label) {
345 ResourceMark rm;
346
347 ShenandoahMessageBuffer msg("Shenandoah verification failed; %s: %s\n\n", _phase, label);
348
349 stringStream ss;
350 r->print_on(&ss);
394 "Complete TAMS should not be larger than top");
395
396 verify(r, r->get_live_data_bytes() <= r->capacity(),
397 "Live data cannot be larger than capacity");
398
399 verify(r, r->garbage() <= r->capacity(),
400 "Garbage cannot be larger than capacity");
401
402 verify(r, r->used() <= r->capacity(),
403 "Used cannot be larger than capacity");
404
405 verify(r, r->get_shared_allocs() <= r->capacity(),
406 "Shared alloc count should not be larger than capacity");
407
408 verify(r, r->get_tlab_allocs() <= r->capacity(),
409 "TLAB alloc count should not be larger than capacity");
410
411 verify(r, r->get_gclab_allocs() <= r->capacity(),
412 "GCLAB alloc count should not be larger than capacity");
413
414 verify(r, r->get_shared_allocs() + r->get_tlab_allocs() + r->get_gclab_allocs() == r->used(),
415 "Accurate accounting: shared + TLAB + GCLAB = used");
416
417 verify(r, !r->is_empty() || !r->has_live(),
418 "Empty regions should not have live data");
419
420 verify(r, r->is_cset() == _heap->collection_set()->is_in(r),
421 "Transitional: region flags and collection set agree");
422 }
423 };
424
425 class ShenandoahVerifierReachableTask : public WorkerTask {
426 private:
427 const char* _label;
428 ShenandoahVerifier::VerifyOptions _options;
429 ShenandoahHeap* _heap;
430 ShenandoahLivenessData* _ld;
431 MarkBitMap* _bitmap;
432 volatile size_t _processed;
433
434 public:
435 ShenandoahVerifierReachableTask(MarkBitMap* bitmap,
472
473 if (ShenandoahVerifyLevel >= 3) {
474 ShenandoahVerifyOopClosure cl(&stack, _bitmap, _ld,
475 ShenandoahMessageBuffer("%s, Reachable", _label),
476 _options);
477 while (!stack.is_empty()) {
478 processed++;
479 ShenandoahVerifierTask task = stack.pop();
480 cl.verify_oops_from(task.obj());
481 }
482 }
483
484 Atomic::add(&_processed, processed, memory_order_relaxed);
485 }
486 };
487
488 class ShenandoahVerifierMarkedRegionTask : public WorkerTask {
489 private:
490 const char* _label;
491 ShenandoahVerifier::VerifyOptions _options;
492 ShenandoahHeap *_heap;
493 MarkBitMap* _bitmap;
494 ShenandoahLivenessData* _ld;
495 volatile size_t _claimed;
496 volatile size_t _processed;
497
498 public:
499 ShenandoahVerifierMarkedRegionTask(MarkBitMap* bitmap,
500 ShenandoahLivenessData* ld,
501 const char* label,
502 ShenandoahVerifier::VerifyOptions options) :
503 WorkerTask("Shenandoah Verifier Marked Objects"),
504 _label(label),
505 _options(options),
506 _heap(ShenandoahHeap::heap()),
507 _bitmap(bitmap),
508 _ld(ld),
509 _claimed(0),
510 _processed(0) {};
511
512 size_t processed() {
513 return Atomic::load(&_processed);
514 }
515
516 virtual void work(uint worker_id) {
517 ShenandoahVerifierStack stack;
518 ShenandoahVerifyOopClosure cl(&stack, _bitmap, _ld,
519 ShenandoahMessageBuffer("%s, Marked", _label),
520 _options);
521
522 while (true) {
523 size_t v = Atomic::fetch_and_add(&_claimed, 1u, memory_order_relaxed);
524 if (v < _heap->num_regions()) {
525 ShenandoahHeapRegion* r = _heap->get_region(v);
526 if (!r->is_humongous() && !r->is_trash()) {
527 work_regular(r, stack, cl);
528 } else if (r->is_humongous_start()) {
529 work_humongous(r, stack, cl);
530 }
531 } else {
532 break;
533 }
534 }
535 }
536
537 virtual void work_humongous(ShenandoahHeapRegion *r, ShenandoahVerifierStack& stack, ShenandoahVerifyOopClosure& cl) {
538 size_t processed = 0;
539 HeapWord* obj = r->bottom();
540 if (_heap->complete_marking_context()->is_marked(cast_to_oop(obj))) {
541 verify_and_follow(obj, stack, cl, &processed);
542 }
543 Atomic::add(&_processed, processed, memory_order_relaxed);
544 }
545
546 virtual void work_regular(ShenandoahHeapRegion *r, ShenandoahVerifierStack &stack, ShenandoahVerifyOopClosure &cl) {
547 size_t processed = 0;
548 ShenandoahMarkingContext* ctx = _heap->complete_marking_context();
549 HeapWord* tams = ctx->top_at_mark_start(r);
550
551 // Bitmaps, before TAMS
552 if (tams > r->bottom()) {
553 HeapWord* start = r->bottom();
554 HeapWord* addr = ctx->get_next_marked_addr(start, tams);
555
556 while (addr < tams) {
557 verify_and_follow(addr, stack, cl, &processed);
558 addr += 1;
559 if (addr < tams) {
560 addr = ctx->get_next_marked_addr(addr, tams);
561 }
562 }
563 }
564
565 // Size-based, after TAMS
566 {
567 HeapWord* limit = r->top();
568 HeapWord* addr = tams;
569
570 while (addr < limit) {
571 verify_and_follow(addr, stack, cl, &processed);
572 addr += cast_to_oop(addr)->size();
573 }
574 }
575
576 Atomic::add(&_processed, processed, memory_order_relaxed);
577 }
578
579 void verify_and_follow(HeapWord *addr, ShenandoahVerifierStack &stack, ShenandoahVerifyOopClosure &cl, size_t *processed) {
580 if (!_bitmap->par_mark(addr)) return;
581
582 // Verify the object itself:
583 oop obj = cast_to_oop(addr);
584 cl.verify_oop_standalone(obj);
585
586 // Verify everything reachable from that object too, hopefully realizing
587 // everything was already marked, and never touching further:
588 if (!is_instance_ref_klass(obj->klass())) {
589 cl.verify_oops_from(obj);
590 (*processed)++;
591 }
592 while (!stack.is_empty()) {
593 ShenandoahVerifierTask task = stack.pop();
594 cl.verify_oops_from(task.obj());
595 (*processed)++;
596 }
597 }
598 };
599
600 class VerifyThreadGCState : public ThreadClosure {
601 private:
602 const char* const _label;
603 char const _expected;
604
605 public:
606 VerifyThreadGCState(const char* label, char expected) : _label(label), _expected(expected) {}
607 void do_thread(Thread* t) {
608 char actual = ShenandoahThreadLocalData::gc_state(t);
609 if (actual != _expected) {
610 fatal("%s: Thread %s: expected gc-state %d, actual %d", _label, t->name(), _expected, actual);
611 }
612 }
613 };
614
615 void ShenandoahVerifier::verify_at_safepoint(const char *label,
616 VerifyForwarded forwarded, VerifyMarked marked,
617 VerifyCollectionSet cset,
618 VerifyLiveness liveness, VerifyRegions regions,
619 VerifyGCState gcstate) {
620 guarantee(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "only when nothing else happens");
621 guarantee(ShenandoahVerify, "only when enabled, and bitmap is initialized in ShenandoahHeap::initialize");
622
623 // Avoid side-effect of changing workers' active thread count, but bypass concurrent/parallel protocol check
624 ShenandoahPushWorkerScope verify_worker_scope(_heap->workers(), _heap->max_workers(), false /*bypass check*/);
625
626 log_info(gc,start)("Verify %s, Level " INTX_FORMAT, label, ShenandoahVerifyLevel);
627
628 // GC state checks
629 {
630 char expected = -1;
631 bool enabled;
632 switch (gcstate) {
633 case _verify_gcstate_disable:
634 enabled = false;
635 break;
636 case _verify_gcstate_forwarded:
637 enabled = true;
638 expected = ShenandoahHeap::HAS_FORWARDED;
639 break;
640 case _verify_gcstate_evacuation:
641 enabled = true;
642 expected = ShenandoahHeap::HAS_FORWARDED | ShenandoahHeap::EVACUATION;
643 if (!_heap->is_stw_gc_in_progress()) {
644 // Only concurrent GC sets this.
645 expected |= ShenandoahHeap::WEAK_ROOTS;
646 }
647 break;
648 case _verify_gcstate_stable:
649 enabled = true;
650 expected = ShenandoahHeap::STABLE;
651 break;
652 case _verify_gcstate_stable_weakroots:
653 enabled = true;
654 expected = ShenandoahHeap::STABLE;
655 if (!_heap->is_stw_gc_in_progress()) {
656 // Only concurrent GC sets this.
657 expected |= ShenandoahHeap::WEAK_ROOTS;
658 }
659 break;
660 default:
661 enabled = false;
662 assert(false, "Unhandled gc-state verification");
663 }
664
665 if (enabled) {
666 char actual = _heap->gc_state();
667 if (actual != expected) {
668 fatal("%s: Global gc-state: expected %d, actual %d", label, expected, actual);
669 }
670
671 VerifyThreadGCState vtgcs(label, expected);
672 Threads::java_threads_do(&vtgcs);
673 }
674 }
675
676 // Deactivate barriers temporarily: Verifier wants plain heap accesses
677 ShenandoahGCStateResetter resetter;
678
679 // Heap size checks
680 {
681 ShenandoahHeapLocker lock(_heap->lock());
682
683 ShenandoahCalculateRegionStatsClosure cl;
684 _heap->heap_region_iterate(&cl);
685 size_t heap_used = _heap->used();
686 guarantee(cl.used() == heap_used,
687 "%s: heap used size must be consistent: heap-used = " SIZE_FORMAT "%s, regions-used = " SIZE_FORMAT "%s",
688 label,
689 byte_size_in_proper_unit(heap_used), proper_unit_for_byte_size(heap_used),
690 byte_size_in_proper_unit(cl.used()), proper_unit_for_byte_size(cl.used()));
691
692 size_t heap_committed = _heap->committed();
693 guarantee(cl.committed() == heap_committed,
694 "%s: heap committed size must be consistent: heap-committed = " SIZE_FORMAT "%s, regions-committed = " SIZE_FORMAT "%s",
695 label,
696 byte_size_in_proper_unit(heap_committed), proper_unit_for_byte_size(heap_committed),
697 byte_size_in_proper_unit(cl.committed()), proper_unit_for_byte_size(cl.committed()));
698 }
699
700 // Internal heap region checks
701 if (ShenandoahVerifyLevel >= 1) {
702 ShenandoahVerifyHeapRegionClosure cl(label, regions);
703 _heap->heap_region_iterate(&cl);
704 }
705
706 OrderAccess::fence();
707
708 if (UseTLAB) {
709 _heap->labs_make_parsable();
710 }
711
712 // Allocate temporary bitmap for storing marking wavefront:
713 _verification_bit_map->clear();
714
715 // Allocate temporary array for storing liveness data
716 ShenandoahLivenessData* ld = NEW_C_HEAP_ARRAY(ShenandoahLivenessData, _heap->num_regions(), mtGC);
717 Copy::fill_to_bytes((void*)ld, _heap->num_regions()*sizeof(ShenandoahLivenessData), 0);
718
719 const VerifyOptions& options = ShenandoahVerifier::VerifyOptions(forwarded, marked, cset, liveness, regions, gcstate);
720
721 // Steps 1-2. Scan root set to get initial reachable set. Finish walking the reachable heap.
722 // This verifies what application can see, since it only cares about reachable objects.
723 size_t count_reachable = 0;
724 if (ShenandoahVerifyLevel >= 2) {
725 ShenandoahVerifierReachableTask task(_verification_bit_map, ld, label, options);
726 _heap->workers()->run_task(&task);
727 count_reachable = task.processed();
728 }
729
730 // Step 3. Walk marked objects. Marked objects might be unreachable. This verifies what collector,
731 // not the application, can see during the region scans. There is no reason to process the objects
732 // that were already verified, e.g. those marked in verification bitmap. There is interaction with TAMS:
733 // before TAMS, we verify the bitmaps, if available; after TAMS, we walk until the top(). It mimics
734 // what marked_object_iterate is doing, without calling into that optimized (and possibly incorrect)
735 // version
736
737 size_t count_marked = 0;
738 if (ShenandoahVerifyLevel >= 4 && (marked == _verify_marked_complete || marked == _verify_marked_complete_except_references)) {
739 guarantee(_heap->marking_context()->is_complete(), "Marking context should be complete");
740 ShenandoahVerifierMarkedRegionTask task(_verification_bit_map, ld, label, options);
741 _heap->workers()->run_task(&task);
742 count_marked = task.processed();
743 } else {
744 guarantee(ShenandoahVerifyLevel < 4 || marked == _verify_marked_incomplete || marked == _verify_marked_disable, "Should be");
745 }
746
747 // Step 4. Verify accumulated liveness data, if needed. Only reliable if verification level includes
748 // marked objects.
749
750 if (ShenandoahVerifyLevel >= 4 && marked == _verify_marked_complete && liveness == _verify_liveness_complete) {
751 for (size_t i = 0; i < _heap->num_regions(); i++) {
752 ShenandoahHeapRegion* r = _heap->get_region(i);
753
754 juint verf_live = 0;
755 if (r->is_humongous()) {
756 // For humongous objects, test if start region is marked live, and if so,
757 // all humongous regions in that chain have live data equal to their "used".
758 juint start_live = Atomic::load(&ld[r->humongous_start_region()->index()]);
759 if (start_live > 0) {
760 verf_live = (juint)(r->used() / HeapWordSize);
761 }
762 } else {
763 verf_live = Atomic::load(&ld[r->index()]);
764 }
765
766 size_t reg_live = r->get_live_data_words();
767 if (reg_live != verf_live) {
768 stringStream ss;
769 r->print_on(&ss);
770 fatal("%s: Live data should match: region-live = " SIZE_FORMAT ", verifier-live = " UINT32_FORMAT "\n%s",
771 label, reg_live, verf_live, ss.freeze());
772 }
773 }
774 }
775
776 log_info(gc)("Verify %s, Level " INTX_FORMAT " (" SIZE_FORMAT " reachable, " SIZE_FORMAT " marked)",
777 label, ShenandoahVerifyLevel, count_reachable, count_marked);
778
779 FREE_C_HEAP_ARRAY(ShenandoahLivenessData, ld);
780 }
781
782 void ShenandoahVerifier::verify_generic(VerifyOption vo) {
783 verify_at_safepoint(
784 "Generic Verification",
785 _verify_forwarded_allow, // conservatively allow forwarded
786 _verify_marked_disable, // do not verify marked: lots ot time wasted checking dead allocations
787 _verify_cset_disable, // cset may be inconsistent
788 _verify_liveness_disable, // no reliable liveness data
789 _verify_regions_disable, // no reliable region data
790 _verify_gcstate_disable // no data about gcstate
791 );
792 }
793
794 void ShenandoahVerifier::verify_before_concmark() {
795 verify_at_safepoint(
796 "Before Mark",
797 _verify_forwarded_none, // UR should have fixed up
798 _verify_marked_disable, // do not verify marked: lots ot time wasted checking dead allocations
799 _verify_cset_none, // UR should have fixed this
800 _verify_liveness_disable, // no reliable liveness data
801 _verify_regions_notrash, // no trash regions
802 _verify_gcstate_stable // there are no forwarded objects
803 );
804 }
805
806 void ShenandoahVerifier::verify_after_concmark() {
807 verify_at_safepoint(
808 "After Mark",
809 _verify_forwarded_none, // no forwarded references
810 _verify_marked_complete_except_references, // bitmaps as precise as we can get, except dangling j.l.r.Refs
811 _verify_cset_none, // no references to cset anymore
812 _verify_liveness_complete, // liveness data must be complete here
813 _verify_regions_disable, // trash regions not yet recycled
814 _verify_gcstate_stable_weakroots // heap is still stable, weakroots are in progress
815 );
816 }
817
818 void ShenandoahVerifier::verify_before_evacuation() {
819 verify_at_safepoint(
820 "Before Evacuation",
821 _verify_forwarded_none, // no forwarded references
822 _verify_marked_complete_except_references, // walk over marked objects too
823 _verify_cset_disable, // non-forwarded references to cset expected
824 _verify_liveness_complete, // liveness data must be complete here
825 _verify_regions_disable, // trash regions not yet recycled
826 _verify_gcstate_stable_weakroots // heap is still stable, weakroots are in progress
827 );
828 }
829
830 void ShenandoahVerifier::verify_during_evacuation() {
831 verify_at_safepoint(
832 "During Evacuation",
833 _verify_forwarded_allow, // some forwarded references are allowed
834 _verify_marked_disable, // walk only roots
835 _verify_cset_disable, // some cset references are not forwarded yet
836 _verify_liveness_disable, // liveness data might be already stale after pre-evacs
837 _verify_regions_disable, // trash regions not yet recycled
838 _verify_gcstate_evacuation // evacuation is in progress
839 );
840 }
841
842 void ShenandoahVerifier::verify_after_evacuation() {
843 verify_at_safepoint(
844 "After Evacuation",
845 _verify_forwarded_allow, // objects are still forwarded
846 _verify_marked_complete, // bitmaps might be stale, but alloc-after-mark should be well
847 _verify_cset_forwarded, // all cset refs are fully forwarded
848 _verify_liveness_disable, // no reliable liveness data anymore
849 _verify_regions_notrash, // trash regions have been recycled already
850 _verify_gcstate_forwarded // evacuation produced some forwarded objects
851 );
852 }
853
854 void ShenandoahVerifier::verify_before_updaterefs() {
855 verify_at_safepoint(
856 "Before Updating References",
857 _verify_forwarded_allow, // forwarded references allowed
858 _verify_marked_complete, // bitmaps might be stale, but alloc-after-mark should be well
859 _verify_cset_forwarded, // all cset refs are fully forwarded
860 _verify_liveness_disable, // no reliable liveness data anymore
861 _verify_regions_notrash, // trash regions have been recycled already
862 _verify_gcstate_forwarded // evacuation should have produced some forwarded objects
863 );
864 }
865
866 void ShenandoahVerifier::verify_after_updaterefs() {
867 verify_at_safepoint(
868 "After Updating References",
869 _verify_forwarded_none, // no forwarded references
870 _verify_marked_complete, // bitmaps might be stale, but alloc-after-mark should be well
871 _verify_cset_none, // no cset references, all updated
872 _verify_liveness_disable, // no reliable liveness data anymore
873 _verify_regions_nocset, // no cset regions, trash regions have appeared
874 _verify_gcstate_stable // update refs had cleaned up forwarded objects
875 );
876 }
877
878 void ShenandoahVerifier::verify_after_degenerated() {
879 verify_at_safepoint(
880 "After Degenerated GC",
881 _verify_forwarded_none, // all objects are non-forwarded
882 _verify_marked_complete, // all objects are marked in complete bitmap
883 _verify_cset_none, // no cset references
884 _verify_liveness_disable, // no reliable liveness data anymore
885 _verify_regions_notrash_nocset, // no trash, no cset
886 _verify_gcstate_stable // degenerated refs had cleaned up forwarded objects
887 );
888 }
889
890 void ShenandoahVerifier::verify_before_fullgc() {
891 verify_at_safepoint(
892 "Before Full GC",
893 _verify_forwarded_allow, // can have forwarded objects
894 _verify_marked_disable, // do not verify marked: lots ot time wasted checking dead allocations
895 _verify_cset_disable, // cset might be foobared
896 _verify_liveness_disable, // no reliable liveness data anymore
897 _verify_regions_disable, // no reliable region data here
898 _verify_gcstate_disable // no reliable gcstate data
899 );
900 }
901
902 void ShenandoahVerifier::verify_after_fullgc() {
903 verify_at_safepoint(
904 "After Full GC",
905 _verify_forwarded_none, // all objects are non-forwarded
906 _verify_marked_complete, // all objects are marked in complete bitmap
907 _verify_cset_none, // no cset references
908 _verify_liveness_disable, // no reliable liveness data anymore
909 _verify_regions_notrash_nocset, // no trash, no cset
910 _verify_gcstate_stable // full gc cleaned up everything
911 );
912 }
913
914 class ShenandoahVerifyNoForwared : public OopClosure {
915 private:
916 template <class T>
917 void do_oop_work(T* p) {
918 T o = RawAccess<>::oop_load(p);
919 if (!CompressedOops::is_null(o)) {
920 oop obj = CompressedOops::decode_not_null(o);
921 oop fwd = ShenandoahForwarding::get_forwardee_raw_unchecked(obj);
922 if (obj != fwd) {
923 ShenandoahAsserts::print_failure(ShenandoahAsserts::_safe_all, obj, p, NULL,
924 "Verify Roots", "Should not be forwarded", __FILE__, __LINE__);
925 }
926 }
927 }
928
929 public:
930 void do_oop(narrowOop* p) { do_oop_work(p); }
931 void do_oop(oop* p) { do_oop_work(p); }
932 };
933
934 class ShenandoahVerifyInToSpaceClosure : public OopClosure {
935 private:
936 template <class T>
937 void do_oop_work(T* p) {
938 T o = RawAccess<>::oop_load(p);
939 if (!CompressedOops::is_null(o)) {
940 oop obj = CompressedOops::decode_not_null(o);
941 ShenandoahHeap* heap = ShenandoahHeap::heap();
942
943 if (!heap->marking_context()->is_marked(obj)) {
944 ShenandoahAsserts::print_failure(ShenandoahAsserts::_safe_all, obj, p, NULL,
945 "Verify Roots In To-Space", "Should be marked", __FILE__, __LINE__);
946 }
947
948 if (heap->in_collection_set(obj)) {
949 ShenandoahAsserts::print_failure(ShenandoahAsserts::_safe_all, obj, p, NULL,
950 "Verify Roots In To-Space", "Should not be in collection set", __FILE__, __LINE__);
951 }
952
953 oop fwd = ShenandoahForwarding::get_forwardee_raw_unchecked(obj);
954 if (obj != fwd) {
955 ShenandoahAsserts::print_failure(ShenandoahAsserts::_safe_all, obj, p, NULL,
956 "Verify Roots In To-Space", "Should not be forwarded", __FILE__, __LINE__);
957 }
958 }
959 }
960
961 public:
962 void do_oop(narrowOop* p) { do_oop_work(p); }
963 void do_oop(oop* p) { do_oop_work(p); }
|
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 "gc/shared/tlab_globals.hpp"
27 #include "gc/shenandoah/shenandoahAsserts.hpp"
28 #include "gc/shenandoah/shenandoahForwarding.inline.hpp"
29 #include "gc/shenandoah/shenandoahPhaseTimings.hpp"
30 #include "gc/shenandoah/shenandoahGeneration.hpp"
31 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
32 #include "gc/shenandoah/shenandoahHeapRegion.inline.hpp"
33 #include "gc/shenandoah/shenandoahOldGeneration.hpp"
34 #include "gc/shenandoah/shenandoahRootProcessor.hpp"
35 #include "gc/shenandoah/shenandoahTaskqueue.inline.hpp"
36 #include "gc/shenandoah/shenandoahUtils.hpp"
37 #include "gc/shenandoah/shenandoahVerifier.hpp"
38 #include "gc/shenandoah/shenandoahYoungGeneration.hpp"
39 #include "memory/allocation.hpp"
40 #include "memory/iterator.inline.hpp"
41 #include "memory/resourceArea.hpp"
42 #include "oops/compressedOops.inline.hpp"
43 #include "runtime/atomic.hpp"
44 #include "runtime/orderAccess.hpp"
45 #include "runtime/threads.hpp"
46 #include "utilities/align.hpp"
47
48 // Avoid name collision on verify_oop (defined in macroAssembler_arm.hpp)
49 #ifdef verify_oop
50 #undef verify_oop
51 #endif
52
53 static bool is_instance_ref_klass(Klass* k) {
54 return k->is_instance_klass() && InstanceKlass::cast(k)->reference_type() != REF_NONE;
55 }
56
57 class ShenandoahIgnoreReferenceDiscoverer : public ReferenceDiscoverer {
58 public:
59 virtual bool discover_reference(oop obj, ReferenceType type) {
60 return true;
61 }
62 };
63
64 class ShenandoahVerifyOopClosure : public BasicOopIterateClosure {
65 private:
66 const char* _phase;
67 ShenandoahVerifier::VerifyOptions _options;
68 ShenandoahVerifierStack* _stack;
69 ShenandoahHeap* _heap;
70 MarkBitMap* _map;
71 ShenandoahLivenessData* _ld;
72 void* _interior_loc;
73 oop _loc;
74 ShenandoahGeneration* _generation;
75
76 public:
77 ShenandoahVerifyOopClosure(ShenandoahVerifierStack* stack, MarkBitMap* map, ShenandoahLivenessData* ld,
78 const char* phase, ShenandoahVerifier::VerifyOptions options) :
79 _phase(phase),
80 _options(options),
81 _stack(stack),
82 _heap(ShenandoahHeap::heap()),
83 _map(map),
84 _ld(ld),
85 _interior_loc(NULL),
86 _loc(NULL),
87 _generation(NULL) {
88 if (options._verify_marked == ShenandoahVerifier::_verify_marked_complete_except_references ||
89 options._verify_marked == ShenandoahVerifier::_verify_marked_disable) {
90 set_ref_discoverer_internal(new ShenandoahIgnoreReferenceDiscoverer());
91 }
92
93 if (_heap->mode()->is_generational()) {
94 _generation = _heap->active_generation();
95 assert(_generation != NULL, "Expected active generation in this mode");
96 }
97 }
98
99 private:
100 void check(ShenandoahAsserts::SafeLevel level, oop obj, bool test, const char* label) {
101 if (!test) {
102 ShenandoahAsserts::print_failure(level, obj, _interior_loc, _loc, _phase, label, __FILE__, __LINE__);
103 }
104 }
105
106 template <class T>
107 void do_oop_work(T* p) {
108 T o = RawAccess<>::oop_load(p);
109 if (!CompressedOops::is_null(o)) {
110 oop obj = CompressedOops::decode_not_null(o);
111 if (is_instance_ref_klass(obj->klass())) {
112 obj = ShenandoahForwarding::get_forwardee(obj);
113 }
114 // Single threaded verification can use faster non-atomic stack and bitmap
115 // methods.
116 //
117 // For performance reasons, only fully verify non-marked field values.
118 // We are here when the host object for *p is already marked.
119
120 if ( in_generation(obj) && _map->par_mark(obj)) {
121 verify_oop_at(p, obj);
122 _stack->push(ShenandoahVerifierTask(obj));
123 }
124 }
125 }
126
127 bool in_generation(oop obj) {
128 if (_generation == NULL) {
129 return true;
130 }
131
132 ShenandoahHeapRegion* region = _heap->heap_region_containing(obj);
133 return _generation->contains(region);
134 }
135
136 void verify_oop(oop obj) {
137 // Perform consistency checks with gradually decreasing safety level. This guarantees
138 // that failure report would not try to touch something that was not yet verified to be
139 // safe to process.
140
141 check(ShenandoahAsserts::_safe_unknown, obj, _heap->is_in(obj),
142 "oop must be in heap");
143 check(ShenandoahAsserts::_safe_unknown, obj, is_object_aligned(obj),
144 "oop must be aligned");
145
146 ShenandoahHeapRegion* obj_reg = _heap->heap_region_containing(obj);
147 Klass* obj_klass = obj->klass_or_null();
148
149 // Verify that obj is not in dead space:
150 {
151 // Do this before touching obj->size()
152 check(ShenandoahAsserts::_safe_unknown, obj, obj_klass != NULL,
153 "Object klass pointer should not be NULL");
154 check(ShenandoahAsserts::_safe_unknown, obj, Metaspace::contains(obj_klass),
155 "Object klass pointer must go to metaspace");
156
157 HeapWord* obj_addr = cast_from_oop<HeapWord*>(obj);
158 check(ShenandoahAsserts::_safe_unknown, obj, obj_addr < obj_reg->top(),
159 "Object start should be within the region");
160
161 if (!obj_reg->is_humongous()) {
162 check(ShenandoahAsserts::_safe_unknown, obj, (obj_addr + obj->size()) <= obj_reg->top(),
163 "Object end should be within the region");
164 } else {
165 size_t humongous_start = obj_reg->index();
166 size_t humongous_end = humongous_start + (obj->size() >> ShenandoahHeapRegion::region_size_words_shift());
167 for (size_t idx = humongous_start + 1; idx < humongous_end; idx++) {
168 check(ShenandoahAsserts::_safe_unknown, obj, _heap->get_region(idx)->is_humongous_continuation(),
169 "Humongous object is in continuation that fits it");
170 }
171 }
172
173 // ------------ obj is safe at this point --------------
174
175 check(ShenandoahAsserts::_safe_oop, obj, obj_reg->is_active(),
176 "Object should be in active region");
177
178 switch (_options._verify_liveness) {
179 case ShenandoahVerifier::_verify_liveness_disable:
180 // skip
181 break;
182 case ShenandoahVerifier::_verify_liveness_complete:
183 Atomic::add(&_ld[obj_reg->index()], (uint) obj->size(), memory_order_relaxed);
184 // fallthrough for fast failure for un-live regions:
185 case ShenandoahVerifier::_verify_liveness_conservative:
186 check(ShenandoahAsserts::_safe_oop, obj, obj_reg->has_live() ||
187 (obj_reg->is_old() && ShenandoahHeap::heap()->is_gc_generation_young()),
188 "Object must belong to region with live data");
189 break;
190 default:
191 assert(false, "Unhandled liveness verification");
192 }
193 }
194
195 oop fwd = ShenandoahForwarding::get_forwardee_raw_unchecked(obj);
196
197 ShenandoahHeapRegion* fwd_reg = NULL;
198
199 if (obj != fwd) {
200 check(ShenandoahAsserts::_safe_oop, obj, _heap->is_in(fwd),
201 "Forwardee must be in heap");
202 check(ShenandoahAsserts::_safe_oop, obj, !CompressedOops::is_null(fwd),
203 "Forwardee is set");
204 check(ShenandoahAsserts::_safe_oop, obj, is_object_aligned(fwd),
205 "Forwardee must be aligned");
206
207 // Do this before touching fwd->size()
208 Klass* fwd_klass = fwd->klass_or_null();
209 check(ShenandoahAsserts::_safe_oop, obj, fwd_klass != NULL,
210 "Forwardee klass pointer should not be NULL");
211 check(ShenandoahAsserts::_safe_oop, obj, Metaspace::contains(fwd_klass),
212 "Forwardee klass pointer must go to metaspace");
213 check(ShenandoahAsserts::_safe_oop, obj, obj_klass == fwd_klass,
214 "Forwardee klass pointer must go to metaspace");
215
216 fwd_reg = _heap->heap_region_containing(fwd);
217
218 // Verify that forwardee is not in the dead space:
219 check(ShenandoahAsserts::_safe_oop, obj, !fwd_reg->is_humongous(),
220 "Should have no humongous forwardees");
221
222 HeapWord* fwd_addr = cast_from_oop<HeapWord* >(fwd);
223 check(ShenandoahAsserts::_safe_oop, obj, fwd_addr < fwd_reg->top(),
224 "Forwardee start should be within the region");
225 check(ShenandoahAsserts::_safe_oop, obj, (fwd_addr + fwd->size()) <= fwd_reg->top(),
226 "Forwardee end should be within the region");
227
228 oop fwd2 = ShenandoahForwarding::get_forwardee_raw_unchecked(fwd);
229 check(ShenandoahAsserts::_safe_oop, obj, (fwd == fwd2),
230 "Double forwarding");
231 } else {
232 fwd_reg = obj_reg;
233 }
234
235 // ------------ obj and fwd are safe at this point --------------
236 // We allow for marked or old here for two reasons:
237 // 1. If this is a young collect, old objects wouldn't be marked. We've
238 // recently change the verifier traversal to only follow young objects
239 // during a young collect so this _shouldn't_ be necessary.
240 // 2. At present, we do not clear dead objects from the remembered set.
241 // Everything in the remembered set is old (ipso facto), so allowing for
242 // 'marked_or_old' covers the case of stale objects in rset.
243 // TODO: Just use 'is_marked' here.
244 switch (_options._verify_marked) {
245 case ShenandoahVerifier::_verify_marked_disable:
246 // skip
247 break;
248 case ShenandoahVerifier::_verify_marked_incomplete:
249 check(ShenandoahAsserts::_safe_all, obj, _heap->marking_context()->is_marked_or_old(obj),
250 "Must be marked in incomplete bitmap");
251 break;
252 case ShenandoahVerifier::_verify_marked_complete:
253 check(ShenandoahAsserts::_safe_all, obj, _heap->complete_marking_context()->is_marked_or_old(obj),
254 "Must be marked in complete bitmap");
255 break;
256 case ShenandoahVerifier::_verify_marked_complete_except_references:
257 check(ShenandoahAsserts::_safe_all, obj, _heap->complete_marking_context()->is_marked_or_old(obj),
258 "Must be marked in complete bitmap, except j.l.r.Reference referents");
259 break;
260 default:
261 assert(false, "Unhandled mark verification");
262 }
263
264 switch (_options._verify_forwarded) {
265 case ShenandoahVerifier::_verify_forwarded_disable:
266 // skip
267 break;
268 case ShenandoahVerifier::_verify_forwarded_none: {
269 check(ShenandoahAsserts::_safe_all, obj, (obj == fwd),
270 "Should not be forwarded");
271 break;
272 }
273 case ShenandoahVerifier::_verify_forwarded_allow: {
274 if (obj != fwd) {
275 check(ShenandoahAsserts::_safe_all, obj, obj_reg != fwd_reg,
276 "Forwardee should be in another region");
277 }
323 void verify_oop_standalone(oop obj) {
324 _interior_loc = NULL;
325 verify_oop(obj);
326 _interior_loc = NULL;
327 }
328
329 /**
330 * Verify oop fields from this object.
331 * @param obj host object for verified fields
332 */
333 void verify_oops_from(oop obj) {
334 _loc = obj;
335 obj->oop_iterate(this);
336 _loc = NULL;
337 }
338
339 virtual void do_oop(oop* p) { do_oop_work(p); }
340 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
341 };
342
343 // This closure computes the amounts of used, committed, and garbage memory and the number of regions contained within
344 // a subset (e.g. the young generation or old generation) of the total heap.
345 class ShenandoahCalculateRegionStatsClosure : public ShenandoahHeapRegionClosure {
346 private:
347 size_t _used, _committed, _garbage, _regions;
348 public:
349 ShenandoahCalculateRegionStatsClosure() : _used(0), _committed(0), _garbage(0), _regions(0) {};
350
351 void heap_region_do(ShenandoahHeapRegion* r) {
352 _used += r->used();
353 log_debug(gc)("ShenandoahCalculateRegionStatsClosure added " SIZE_FORMAT " for %s Region " SIZE_FORMAT ", yielding: " SIZE_FORMAT,
354 r->used(), r->is_humongous()? "humongous": "regular", r->index(), _used);
355 _garbage += r->garbage();
356 _committed += r->is_committed() ? ShenandoahHeapRegion::region_size_bytes() : 0;
357 _regions++;
358 }
359
360 size_t used() { return _used; }
361 size_t committed() { return _committed; }
362 size_t garbage() { return _garbage; }
363 size_t regions() { return _regions; }
364
365 // span is the total memory affiliated with these stats (some of which is in use and other is available)
366 size_t span() { return _regions * ShenandoahHeapRegion::region_size_bytes(); }
367 };
368
369 class ShenandoahGenerationStatsClosure : public ShenandoahHeapRegionClosure {
370 public:
371 ShenandoahCalculateRegionStatsClosure old;
372 ShenandoahCalculateRegionStatsClosure young;
373 ShenandoahCalculateRegionStatsClosure global;
374
375 void heap_region_do(ShenandoahHeapRegion* r) override {
376 switch (r->affiliation()) {
377 default:
378 ShouldNotReachHere();
379 return;
380 case FREE: return;
381 case YOUNG_GENERATION:
382 young.heap_region_do(r);
383 break;
384 case OLD_GENERATION:
385 old.heap_region_do(r);
386 break;
387 }
388 global.heap_region_do(r);
389 }
390
391 static void log_usage(ShenandoahGeneration* generation, ShenandoahCalculateRegionStatsClosure& stats) {
392 log_debug(gc)("Safepoint verification: %s verified usage: " SIZE_FORMAT "%s, recorded usage: " SIZE_FORMAT "%s",
393 generation->name(),
394 byte_size_in_proper_unit(generation->used()), proper_unit_for_byte_size(generation->used()),
395 byte_size_in_proper_unit(stats.used()), proper_unit_for_byte_size(stats.used()));
396 }
397
398 static void validate_usage(const char* label, ShenandoahGeneration* generation, ShenandoahCalculateRegionStatsClosure& stats) {
399 size_t generation_used = generation->used();
400 guarantee(stats.used() == generation_used,
401 "%s: generation (%s) used size must be consistent: generation-used = " SIZE_FORMAT "%s, regions-used = " SIZE_FORMAT "%s",
402 label, generation->name(),
403 byte_size_in_proper_unit(generation_used), proper_unit_for_byte_size(generation_used),
404 byte_size_in_proper_unit(stats.used()), proper_unit_for_byte_size(stats.used()));
405
406 guarantee(stats.regions() == generation->used_regions(),
407 "%s: generation (%s) used regions (" SIZE_FORMAT ") must equal regions that are in use (" SIZE_FORMAT ")",
408 label, generation->name(), generation->used_regions(), stats.regions());
409
410 size_t capacity = generation->adjusted_capacity();
411 guarantee(stats.span() <= capacity,
412 "%s: generation (%s) size spanned by regions (" SIZE_FORMAT ") must not exceed current capacity (" SIZE_FORMAT "%s)",
413 label, generation->name(), stats.regions(),
414 byte_size_in_proper_unit(capacity), proper_unit_for_byte_size(capacity));
415
416 }
417 };
418
419 class ShenandoahVerifyHeapRegionClosure : public ShenandoahHeapRegionClosure {
420 private:
421 ShenandoahHeap* _heap;
422 const char* _phase;
423 ShenandoahVerifier::VerifyRegions _regions;
424 public:
425 ShenandoahVerifyHeapRegionClosure(const char* phase, ShenandoahVerifier::VerifyRegions regions) :
426 _heap(ShenandoahHeap::heap()),
427 _phase(phase),
428 _regions(regions) {};
429
430 void print_failure(ShenandoahHeapRegion* r, const char* label) {
431 ResourceMark rm;
432
433 ShenandoahMessageBuffer msg("Shenandoah verification failed; %s: %s\n\n", _phase, label);
434
435 stringStream ss;
436 r->print_on(&ss);
480 "Complete TAMS should not be larger than top");
481
482 verify(r, r->get_live_data_bytes() <= r->capacity(),
483 "Live data cannot be larger than capacity");
484
485 verify(r, r->garbage() <= r->capacity(),
486 "Garbage cannot be larger than capacity");
487
488 verify(r, r->used() <= r->capacity(),
489 "Used cannot be larger than capacity");
490
491 verify(r, r->get_shared_allocs() <= r->capacity(),
492 "Shared alloc count should not be larger than capacity");
493
494 verify(r, r->get_tlab_allocs() <= r->capacity(),
495 "TLAB alloc count should not be larger than capacity");
496
497 verify(r, r->get_gclab_allocs() <= r->capacity(),
498 "GCLAB alloc count should not be larger than capacity");
499
500 verify(r, r->get_plab_allocs() <= r->capacity(),
501 "PLAB alloc count should not be larger than capacity");
502
503 verify(r, r->get_shared_allocs() + r->get_tlab_allocs() + r->get_gclab_allocs() + r->get_plab_allocs() == r->used(),
504 "Accurate accounting: shared + TLAB + GCLAB + PLAB = used");
505
506 verify(r, !r->is_empty() || !r->has_live(),
507 "Empty regions should not have live data");
508
509 verify(r, r->is_cset() == _heap->collection_set()->is_in(r),
510 "Transitional: region flags and collection set agree");
511 }
512 };
513
514 class ShenandoahVerifierReachableTask : public WorkerTask {
515 private:
516 const char* _label;
517 ShenandoahVerifier::VerifyOptions _options;
518 ShenandoahHeap* _heap;
519 ShenandoahLivenessData* _ld;
520 MarkBitMap* _bitmap;
521 volatile size_t _processed;
522
523 public:
524 ShenandoahVerifierReachableTask(MarkBitMap* bitmap,
561
562 if (ShenandoahVerifyLevel >= 3) {
563 ShenandoahVerifyOopClosure cl(&stack, _bitmap, _ld,
564 ShenandoahMessageBuffer("%s, Reachable", _label),
565 _options);
566 while (!stack.is_empty()) {
567 processed++;
568 ShenandoahVerifierTask task = stack.pop();
569 cl.verify_oops_from(task.obj());
570 }
571 }
572
573 Atomic::add(&_processed, processed, memory_order_relaxed);
574 }
575 };
576
577 class ShenandoahVerifierMarkedRegionTask : public WorkerTask {
578 private:
579 const char* _label;
580 ShenandoahVerifier::VerifyOptions _options;
581 ShenandoahHeap* _heap;
582 MarkBitMap* _bitmap;
583 ShenandoahLivenessData* _ld;
584 volatile size_t _claimed;
585 volatile size_t _processed;
586 ShenandoahGeneration* _generation;
587
588 public:
589 ShenandoahVerifierMarkedRegionTask(MarkBitMap* bitmap,
590 ShenandoahLivenessData* ld,
591 const char* label,
592 ShenandoahVerifier::VerifyOptions options) :
593 WorkerTask("Shenandoah Verifier Marked Objects"),
594 _label(label),
595 _options(options),
596 _heap(ShenandoahHeap::heap()),
597 _bitmap(bitmap),
598 _ld(ld),
599 _claimed(0),
600 _processed(0),
601 _generation(NULL) {
602 if (_heap->mode()->is_generational()) {
603 _generation = _heap->active_generation();
604 assert(_generation != NULL, "Expected active generation in this mode.");
605 }
606 };
607
608 size_t processed() {
609 return Atomic::load(&_processed);
610 }
611
612 virtual void work(uint worker_id) {
613 ShenandoahVerifierStack stack;
614 ShenandoahVerifyOopClosure cl(&stack, _bitmap, _ld,
615 ShenandoahMessageBuffer("%s, Marked", _label),
616 _options);
617
618 while (true) {
619 size_t v = Atomic::fetch_and_add(&_claimed, 1u, memory_order_relaxed);
620 if (v < _heap->num_regions()) {
621 ShenandoahHeapRegion* r = _heap->get_region(v);
622 if (!in_generation(r)) {
623 continue;
624 }
625
626 if (!r->is_humongous() && !r->is_trash()) {
627 work_regular(r, stack, cl);
628 } else if (r->is_humongous_start()) {
629 work_humongous(r, stack, cl);
630 }
631 } else {
632 break;
633 }
634 }
635 }
636
637 bool in_generation(ShenandoahHeapRegion* r) {
638 return _generation == NULL || _generation->contains(r);
639 }
640
641 virtual void work_humongous(ShenandoahHeapRegion* r, ShenandoahVerifierStack& stack, ShenandoahVerifyOopClosure& cl) {
642 size_t processed = 0;
643 HeapWord* obj = r->bottom();
644 if (_heap->complete_marking_context()->is_marked(cast_to_oop(obj))) {
645 verify_and_follow(obj, stack, cl, &processed);
646 }
647 Atomic::add(&_processed, processed, memory_order_relaxed);
648 }
649
650 virtual void work_regular(ShenandoahHeapRegion* r, ShenandoahVerifierStack &stack, ShenandoahVerifyOopClosure &cl) {
651 size_t processed = 0;
652 ShenandoahMarkingContext* ctx = _heap->complete_marking_context();
653 HeapWord* tams = ctx->top_at_mark_start(r);
654
655 // Bitmaps, before TAMS
656 if (tams > r->bottom()) {
657 HeapWord* start = r->bottom();
658 HeapWord* addr = ctx->get_next_marked_addr(start, tams);
659
660 while (addr < tams) {
661 verify_and_follow(addr, stack, cl, &processed);
662 addr += 1;
663 if (addr < tams) {
664 addr = ctx->get_next_marked_addr(addr, tams);
665 }
666 }
667 }
668
669 // Size-based, after TAMS
670 {
671 HeapWord* limit = r->top();
672 HeapWord* addr = tams;
673
674 while (addr < limit) {
675 verify_and_follow(addr, stack, cl, &processed);
676 addr += cast_to_oop(addr)->size();
677 }
678 }
679
680 Atomic::add(&_processed, processed, memory_order_relaxed);
681 }
682
683 void verify_and_follow(HeapWord* addr, ShenandoahVerifierStack &stack, ShenandoahVerifyOopClosure &cl, size_t* processed) {
684 if (!_bitmap->par_mark(addr)) return;
685
686 // Verify the object itself:
687 oop obj = cast_to_oop(addr);
688 cl.verify_oop_standalone(obj);
689
690 // Verify everything reachable from that object too, hopefully realizing
691 // everything was already marked, and never touching further:
692 if (!is_instance_ref_klass(obj->klass())) {
693 cl.verify_oops_from(obj);
694 (*processed)++;
695 }
696 while (!stack.is_empty()) {
697 ShenandoahVerifierTask task = stack.pop();
698 cl.verify_oops_from(task.obj());
699 (*processed)++;
700 }
701 }
702 };
703
704 class VerifyThreadGCState : public ThreadClosure {
705 private:
706 const char* const _label;
707 char const _expected;
708
709 public:
710 VerifyThreadGCState(const char* label, char expected) : _label(label), _expected(expected) {}
711 void do_thread(Thread* t) {
712 char actual = ShenandoahThreadLocalData::gc_state(t);
713 if (actual != _expected && !(actual & ShenandoahHeap::OLD_MARKING)) {
714 fatal("%s: Thread %s: expected gc-state %d, actual %d", _label, t->name(), _expected, actual);
715 }
716 }
717 };
718
719 void ShenandoahVerifier::verify_at_safepoint(const char* label,
720 VerifyRememberedSet remembered,
721 VerifyForwarded forwarded, VerifyMarked marked,
722 VerifyCollectionSet cset,
723 VerifyLiveness liveness, VerifyRegions regions,
724 VerifyGCState gcstate) {
725 guarantee(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "only when nothing else happens");
726 guarantee(ShenandoahVerify, "only when enabled, and bitmap is initialized in ShenandoahHeap::initialize");
727
728 // Avoid side-effect of changing workers' active thread count, but bypass concurrent/parallel protocol check
729 ShenandoahPushWorkerScope verify_worker_scope(_heap->workers(), _heap->max_workers(), false /*bypass check*/);
730
731 log_info(gc,start)("Verify %s, Level " INTX_FORMAT, label, ShenandoahVerifyLevel);
732
733 // GC state checks
734 {
735 char expected = -1;
736 bool enabled;
737 switch (gcstate) {
738 case _verify_gcstate_disable:
739 enabled = false;
740 break;
741 case _verify_gcstate_forwarded:
742 enabled = true;
743 expected = ShenandoahHeap::HAS_FORWARDED;
744 break;
745 case _verify_gcstate_evacuation:
746 enabled = true;
747 expected = ShenandoahHeap::HAS_FORWARDED | ShenandoahHeap::EVACUATION;
748 if (!_heap->is_stw_gc_in_progress()) {
749 // Only concurrent GC sets this.
750 expected |= ShenandoahHeap::WEAK_ROOTS;
751 }
752 break;
753 case _verify_gcstate_updating:
754 enabled = true;
755 expected = ShenandoahHeap::HAS_FORWARDED | ShenandoahHeap::UPDATEREFS;
756 break;
757 case _verify_gcstate_stable:
758 enabled = true;
759 expected = ShenandoahHeap::STABLE;
760 break;
761 case _verify_gcstate_stable_weakroots:
762 enabled = true;
763 expected = ShenandoahHeap::STABLE;
764 if (!_heap->is_stw_gc_in_progress()) {
765 // Only concurrent GC sets this.
766 expected |= ShenandoahHeap::WEAK_ROOTS;
767 }
768 break;
769 default:
770 enabled = false;
771 assert(false, "Unhandled gc-state verification");
772 }
773
774 if (enabled) {
775 char actual = _heap->gc_state();
776 // Old generation marking is allowed in all states.
777 if (actual != expected && !(actual & ShenandoahHeap::OLD_MARKING)) {
778 fatal("%s: Global gc-state: expected %d, actual %d", label, expected, actual);
779 }
780
781 VerifyThreadGCState vtgcs(label, expected);
782 Threads::java_threads_do(&vtgcs);
783 }
784 }
785
786 // Deactivate barriers temporarily: Verifier wants plain heap accesses
787 ShenandoahGCStateResetter resetter;
788
789 // Heap size checks
790 {
791 ShenandoahHeapLocker lock(_heap->lock());
792
793 ShenandoahCalculateRegionStatsClosure cl;
794 _heap->heap_region_iterate(&cl);
795 size_t heap_used = _heap->used();
796 guarantee(cl.used() == heap_used,
797 "%s: heap used size must be consistent: heap-used = " SIZE_FORMAT "%s, regions-used = " SIZE_FORMAT "%s",
798 label,
799 byte_size_in_proper_unit(heap_used), proper_unit_for_byte_size(heap_used),
800 byte_size_in_proper_unit(cl.used()), proper_unit_for_byte_size(cl.used()));
801
802 size_t heap_committed = _heap->committed();
803 guarantee(cl.committed() == heap_committed,
804 "%s: heap committed size must be consistent: heap-committed = " SIZE_FORMAT "%s, regions-committed = " SIZE_FORMAT "%s",
805 label,
806 byte_size_in_proper_unit(heap_committed), proper_unit_for_byte_size(heap_committed),
807 byte_size_in_proper_unit(cl.committed()), proper_unit_for_byte_size(cl.committed()));
808 }
809
810 log_debug(gc)("Safepoint verification finished heap usage verification");
811
812 ShenandoahGeneration* generation;
813 if (_heap->mode()->is_generational()) {
814 generation = _heap->active_generation();
815 guarantee(generation != NULL, "Need to know which generation to verify.");
816 } else {
817 generation = NULL;
818 }
819
820 if (generation != NULL) {
821 ShenandoahHeapLocker lock(_heap->lock());
822
823 if (remembered == _verify_remembered_for_marking) {
824 log_debug(gc)("Safepoint verification of remembered set at mark");
825 } else if (remembered == _verify_remembered_for_updating_references) {
826 log_debug(gc)("Safepoint verification of remembered set at update ref");
827 } else if (remembered == _verify_remembered_after_full_gc) {
828 log_debug(gc)("Safepoint verification of remembered set after full gc");
829 }
830
831 if (remembered == _verify_remembered_for_marking) {
832 _heap->verify_rem_set_at_mark();
833 } else if (remembered == _verify_remembered_for_updating_references) {
834 _heap->verify_rem_set_at_update_ref();
835 } else if (remembered == _verify_remembered_after_full_gc) {
836 _heap->verify_rem_set_after_full_gc();
837 }
838
839 ShenandoahGenerationStatsClosure cl;
840 _heap->heap_region_iterate(&cl);
841
842 if (LogTarget(Debug, gc)::is_enabled()) {
843 ShenandoahGenerationStatsClosure::log_usage(_heap->old_generation(), cl.old);
844 ShenandoahGenerationStatsClosure::log_usage(_heap->young_generation(), cl.young);
845 ShenandoahGenerationStatsClosure::log_usage(_heap->global_generation(), cl.global);
846 }
847
848 ShenandoahGenerationStatsClosure::validate_usage(label, _heap->old_generation(), cl.old);
849 ShenandoahGenerationStatsClosure::validate_usage(label, _heap->young_generation(), cl.young);
850 ShenandoahGenerationStatsClosure::validate_usage(label, _heap->global_generation(), cl.global);
851 }
852
853 log_debug(gc)("Safepoint verification finished remembered set verification");
854
855 // Internal heap region checks
856 if (ShenandoahVerifyLevel >= 1) {
857 ShenandoahVerifyHeapRegionClosure cl(label, regions);
858 if (generation != NULL) {
859 generation->heap_region_iterate(&cl);
860 } else {
861 _heap->heap_region_iterate(&cl);
862 }
863 }
864
865 log_debug(gc)("Safepoint verification finished heap region closure verification");
866
867 OrderAccess::fence();
868
869 if (UseTLAB) {
870 _heap->labs_make_parsable();
871 }
872
873 // Allocate temporary bitmap for storing marking wavefront:
874 _verification_bit_map->clear();
875
876 // Allocate temporary array for storing liveness data
877 ShenandoahLivenessData* ld = NEW_C_HEAP_ARRAY(ShenandoahLivenessData, _heap->num_regions(), mtGC);
878 Copy::fill_to_bytes((void*)ld, _heap->num_regions()*sizeof(ShenandoahLivenessData), 0);
879
880 const VerifyOptions& options = ShenandoahVerifier::VerifyOptions(forwarded, marked, cset, liveness, regions, gcstate);
881
882 // Steps 1-2. Scan root set to get initial reachable set. Finish walking the reachable heap.
883 // This verifies what application can see, since it only cares about reachable objects.
884 size_t count_reachable = 0;
885 if (ShenandoahVerifyLevel >= 2) {
886 ShenandoahVerifierReachableTask task(_verification_bit_map, ld, label, options);
887 _heap->workers()->run_task(&task);
888 count_reachable = task.processed();
889 }
890
891 log_debug(gc)("Safepoint verification finished getting initial reachable set");
892
893 // Step 3. Walk marked objects. Marked objects might be unreachable. This verifies what collector,
894 // not the application, can see during the region scans. There is no reason to process the objects
895 // that were already verified, e.g. those marked in verification bitmap. There is interaction with TAMS:
896 // before TAMS, we verify the bitmaps, if available; after TAMS, we walk until the top(). It mimics
897 // what marked_object_iterate is doing, without calling into that optimized (and possibly incorrect)
898 // version
899
900 size_t count_marked = 0;
901 if (ShenandoahVerifyLevel >= 4 && (marked == _verify_marked_complete || marked == _verify_marked_complete_except_references)) {
902 guarantee(_heap->marking_context()->is_complete(), "Marking context should be complete");
903 ShenandoahVerifierMarkedRegionTask task(_verification_bit_map, ld, label, options);
904 _heap->workers()->run_task(&task);
905 count_marked = task.processed();
906 } else {
907 guarantee(ShenandoahVerifyLevel < 4 || marked == _verify_marked_incomplete || marked == _verify_marked_disable, "Should be");
908 }
909
910 log_debug(gc)("Safepoint verification finished walking marked objects");
911
912 // Step 4. Verify accumulated liveness data, if needed. Only reliable if verification level includes
913 // marked objects.
914
915 if (ShenandoahVerifyLevel >= 4 && marked == _verify_marked_complete && liveness == _verify_liveness_complete) {
916 for (size_t i = 0; i < _heap->num_regions(); i++) {
917 ShenandoahHeapRegion* r = _heap->get_region(i);
918 if (generation != NULL && !generation->contains(r)) {
919 continue;
920 }
921
922 juint verf_live = 0;
923 if (r->is_humongous()) {
924 // For humongous objects, test if start region is marked live, and if so,
925 // all humongous regions in that chain have live data equal to their "used".
926 juint start_live = Atomic::load(&ld[r->humongous_start_region()->index()]);
927 if (start_live > 0) {
928 verf_live = (juint)(r->used() / HeapWordSize);
929 }
930 } else {
931 verf_live = Atomic::load(&ld[r->index()]);
932 }
933
934 size_t reg_live = r->get_live_data_words();
935 if (reg_live != verf_live) {
936 stringStream ss;
937 r->print_on(&ss);
938 fatal("%s: Live data should match: region-live = " SIZE_FORMAT ", verifier-live = " UINT32_FORMAT "\n%s",
939 label, reg_live, verf_live, ss.freeze());
940 }
941 }
942 }
943
944 log_debug(gc)("Safepoint verification finished accumulation of liveness data");
945
946
947 log_info(gc)("Verify %s, Level " INTX_FORMAT " (" SIZE_FORMAT " reachable, " SIZE_FORMAT " marked)",
948 label, ShenandoahVerifyLevel, count_reachable, count_marked);
949
950 FREE_C_HEAP_ARRAY(ShenandoahLivenessData, ld);
951 }
952
953 void ShenandoahVerifier::verify_generic(VerifyOption vo) {
954 verify_at_safepoint(
955 "Generic Verification",
956 _verify_remembered_disable, // do not verify remembered set
957 _verify_forwarded_allow, // conservatively allow forwarded
958 _verify_marked_disable, // do not verify marked: lots ot time wasted checking dead allocations
959 _verify_cset_disable, // cset may be inconsistent
960 _verify_liveness_disable, // no reliable liveness data
961 _verify_regions_disable, // no reliable region data
962 _verify_gcstate_disable // no data about gcstate
963 );
964 }
965
966 void ShenandoahVerifier::verify_before_concmark() {
967 verify_at_safepoint(
968 "Before Mark",
969 _verify_remembered_for_marking, // verify read-only remembered set from bottom() to top()
970 _verify_forwarded_none, // UR should have fixed up
971 _verify_marked_disable, // do not verify marked: lots ot time wasted checking dead allocations
972 _verify_cset_none, // UR should have fixed this
973 _verify_liveness_disable, // no reliable liveness data
974 _verify_regions_notrash, // no trash regions
975 _verify_gcstate_stable // there are no forwarded objects
976 );
977 }
978
979 void ShenandoahVerifier::verify_after_concmark() {
980 verify_at_safepoint(
981 "After Mark",
982 _verify_remembered_disable, // do not verify remembered set
983 _verify_forwarded_none, // no forwarded references
984 _verify_marked_complete_except_references, // bitmaps as precise as we can get, except dangling j.l.r.Refs
985 _verify_cset_none, // no references to cset anymore
986 _verify_liveness_complete, // liveness data must be complete here
987 _verify_regions_disable, // trash regions not yet recycled
988 _verify_gcstate_stable_weakroots // heap is still stable, weakroots are in progress
989 );
990 }
991
992 void ShenandoahVerifier::verify_before_evacuation() {
993 verify_at_safepoint(
994 "Before Evacuation",
995 _verify_remembered_disable, // do not verify remembered set
996 _verify_forwarded_none, // no forwarded references
997 _verify_marked_complete_except_references, // walk over marked objects too
998 _verify_cset_disable, // non-forwarded references to cset expected
999 _verify_liveness_complete, // liveness data must be complete here
1000 _verify_regions_disable, // trash regions not yet recycled
1001 _verify_gcstate_stable_weakroots // heap is still stable, weakroots are in progress
1002 );
1003 }
1004
1005 void ShenandoahVerifier::verify_during_evacuation() {
1006 verify_at_safepoint(
1007 "During Evacuation",
1008 _verify_remembered_disable, // do not verify remembered set
1009 _verify_forwarded_allow, // some forwarded references are allowed
1010 _verify_marked_disable, // walk only roots
1011 _verify_cset_disable, // some cset references are not forwarded yet
1012 _verify_liveness_disable, // liveness data might be already stale after pre-evacs
1013 _verify_regions_disable, // trash regions not yet recycled
1014 _verify_gcstate_evacuation // evacuation is in progress
1015 );
1016 }
1017
1018 void ShenandoahVerifier::verify_after_evacuation() {
1019 verify_at_safepoint(
1020 "After Evacuation",
1021 _verify_remembered_disable, // do not verify remembered set
1022 _verify_forwarded_allow, // objects are still forwarded
1023 _verify_marked_complete, // bitmaps might be stale, but alloc-after-mark should be well
1024 _verify_cset_forwarded, // all cset refs are fully forwarded
1025 _verify_liveness_disable, // no reliable liveness data anymore
1026 _verify_regions_notrash, // trash regions have been recycled already
1027 _verify_gcstate_forwarded // evacuation produced some forwarded objects
1028 );
1029 }
1030
1031 void ShenandoahVerifier::verify_before_updaterefs() {
1032 verify_at_safepoint(
1033 "Before Updating References",
1034 _verify_remembered_for_updating_references, // verify read-write remembered set
1035 _verify_forwarded_allow, // forwarded references allowed
1036 _verify_marked_complete, // bitmaps might be stale, but alloc-after-mark should be well
1037 _verify_cset_forwarded, // all cset refs are fully forwarded
1038 _verify_liveness_disable, // no reliable liveness data anymore
1039 _verify_regions_notrash, // trash regions have been recycled already
1040 _verify_gcstate_updating // evacuation should have produced some forwarded objects
1041 );
1042 }
1043
1044 void ShenandoahVerifier::verify_after_updaterefs() {
1045 verify_at_safepoint(
1046 "After Updating References",
1047 _verify_remembered_disable, // do not verify remembered set
1048 _verify_forwarded_none, // no forwarded references
1049 _verify_marked_complete, // bitmaps might be stale, but alloc-after-mark should be well
1050 _verify_cset_none, // no cset references, all updated
1051 _verify_liveness_disable, // no reliable liveness data anymore
1052 _verify_regions_nocset, // no cset regions, trash regions have appeared
1053 _verify_gcstate_stable // update refs had cleaned up forwarded objects
1054 );
1055 }
1056
1057 void ShenandoahVerifier::verify_after_degenerated() {
1058 verify_at_safepoint(
1059 "After Degenerated GC",
1060 _verify_remembered_disable, // do not verify remembered set
1061 _verify_forwarded_none, // all objects are non-forwarded
1062 _verify_marked_complete, // all objects are marked in complete bitmap
1063 _verify_cset_none, // no cset references
1064 _verify_liveness_disable, // no reliable liveness data anymore
1065 _verify_regions_notrash_nocset, // no trash, no cset
1066 _verify_gcstate_stable // degenerated refs had cleaned up forwarded objects
1067 );
1068 }
1069
1070 void ShenandoahVerifier::verify_before_fullgc() {
1071 verify_at_safepoint(
1072 "Before Full GC",
1073 _verify_remembered_disable, // do not verify remembered set
1074 _verify_forwarded_allow, // can have forwarded objects
1075 _verify_marked_disable, // do not verify marked: lots ot time wasted checking dead allocations
1076 _verify_cset_disable, // cset might be foobared
1077 _verify_liveness_disable, // no reliable liveness data anymore
1078 _verify_regions_disable, // no reliable region data here
1079 _verify_gcstate_disable // no reliable gcstate data
1080 );
1081 }
1082
1083 void ShenandoahVerifier::verify_after_generational_fullgc() {
1084 verify_at_safepoint(
1085 "After Full Generational GC",
1086 _verify_remembered_after_full_gc, // verify read-write remembered set
1087 _verify_forwarded_none, // all objects are non-forwarded
1088 _verify_marked_complete, // all objects are marked in complete bitmap
1089 _verify_cset_none, // no cset references
1090 _verify_liveness_disable, // no reliable liveness data anymore
1091 _verify_regions_notrash_nocset, // no trash, no cset
1092 _verify_gcstate_stable // full gc cleaned up everything
1093 );
1094 }
1095
1096 void ShenandoahVerifier::verify_after_fullgc() {
1097 verify_at_safepoint(
1098 "After Full GC",
1099 _verify_remembered_disable, // do not verify remembered set
1100 _verify_forwarded_none, // all objects are non-forwarded
1101 _verify_marked_complete, // all objects are marked in complete bitmap
1102 _verify_cset_none, // no cset references
1103 _verify_liveness_disable, // no reliable liveness data anymore
1104 _verify_regions_notrash_nocset, // no trash, no cset
1105 _verify_gcstate_stable // full gc cleaned up everything
1106 );
1107 }
1108
1109 class ShenandoahVerifyNoForwared : public BasicOopIterateClosure {
1110 private:
1111 template <class T>
1112 void do_oop_work(T* p) {
1113 T o = RawAccess<>::oop_load(p);
1114 if (!CompressedOops::is_null(o)) {
1115 oop obj = CompressedOops::decode_not_null(o);
1116 oop fwd = ShenandoahForwarding::get_forwardee_raw_unchecked(obj);
1117 if (obj != fwd) {
1118 ShenandoahAsserts::print_failure(ShenandoahAsserts::_safe_all, obj, p, NULL,
1119 "Verify Roots", "Should not be forwarded", __FILE__, __LINE__);
1120 }
1121 }
1122 }
1123
1124 public:
1125 void do_oop(narrowOop* p) { do_oop_work(p); }
1126 void do_oop(oop* p) { do_oop_work(p); }
1127 };
1128
1129 class ShenandoahVerifyInToSpaceClosure : public BasicOopIterateClosure {
1130 private:
1131 template <class T>
1132 void do_oop_work(T* p) {
1133 T o = RawAccess<>::oop_load(p);
1134 if (!CompressedOops::is_null(o)) {
1135 oop obj = CompressedOops::decode_not_null(o);
1136 ShenandoahHeap* heap = ShenandoahHeap::heap();
1137
1138 if (!heap->marking_context()->is_marked_or_old(obj)) {
1139 ShenandoahAsserts::print_failure(ShenandoahAsserts::_safe_all, obj, p, NULL,
1140 "Verify Roots In To-Space", "Should be marked", __FILE__, __LINE__);
1141 }
1142
1143 if (heap->in_collection_set(obj)) {
1144 ShenandoahAsserts::print_failure(ShenandoahAsserts::_safe_all, obj, p, NULL,
1145 "Verify Roots In To-Space", "Should not be in collection set", __FILE__, __LINE__);
1146 }
1147
1148 oop fwd = ShenandoahForwarding::get_forwardee_raw_unchecked(obj);
1149 if (obj != fwd) {
1150 ShenandoahAsserts::print_failure(ShenandoahAsserts::_safe_all, obj, p, NULL,
1151 "Verify Roots In To-Space", "Should not be forwarded", __FILE__, __LINE__);
1152 }
1153 }
1154 }
1155
1156 public:
1157 void do_oop(narrowOop* p) { do_oop_work(p); }
1158 void do_oop(oop* p) { do_oop_work(p); }
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