From 5abb9f95978f5685cdcda9f0f9d8864f2573f03e Mon Sep 17 00:00:00 2001 From: poonam Date: Mon, 1 Feb 2016 13:19:14 -0800 Subject: [PATCH] 8145442: Add the facility to verify remembered sets for G1 Summary: Implement remembered sets verification for G1 with option VerifyRememberedSets Reviewed-by: jmasa, mgerdin --- .../gc_implementation/g1/g1CollectedHeap.cpp | 26 +++ .../vm/gc_implementation/g1/heapRegion.cpp | 189 +++++++++++++----- .../vm/gc_implementation/g1/heapRegion.hpp | 3 + 3 files changed, 167 insertions(+), 51 deletions(-) diff --git a/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp b/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp index 7d118edb5..6b654a5bf 100644 --- a/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp +++ b/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp @@ -3839,6 +3839,16 @@ G1CollectedHeap::cleanup_surviving_young_words() { _surviving_young_words = NULL; } +class VerifyRegionRemSetClosure : public HeapRegionClosure { + public: + bool doHeapRegion(HeapRegion* hr) { + if (!hr->continuesHumongous()) { + hr->verify_rem_set(); + } + return false; + } +}; + #ifdef ASSERT class VerifyCSetClosure: public HeapRegionClosure { public: @@ -4015,6 +4025,14 @@ G1CollectedHeap::do_collection_pause_at_safepoint(double target_pause_time_ms) { increment_total_collections(false /* full gc */); increment_gc_time_stamp(); + if (VerifyRememberedSets) { + if (!VerifySilently) { + gclog_or_tty->print_cr("[Verifying RemSets before GC]"); + } + VerifyRegionRemSetClosure v_cl; + heap_region_iterate(&v_cl); + } + verify_before_gc(); check_bitmaps("GC Start"); @@ -4246,6 +4264,14 @@ G1CollectedHeap::do_collection_pause_at_safepoint(double target_pause_time_ms) { // scanning cards (see CR 7039627). increment_gc_time_stamp(); + if (VerifyRememberedSets) { + if (!VerifySilently) { + gclog_or_tty->print_cr("[Verifying RemSets after GC]"); + } + VerifyRegionRemSetClosure v_cl; + heap_region_iterate(&v_cl); + } + verify_after_gc(); check_bitmaps("GC End"); diff --git a/src/share/vm/gc_implementation/g1/heapRegion.cpp b/src/share/vm/gc_implementation/g1/heapRegion.cpp index d5a4b2617..d95d37949 100644 --- a/src/share/vm/gc_implementation/g1/heapRegion.cpp +++ b/src/share/vm/gc_implementation/g1/heapRegion.cpp @@ -639,8 +639,8 @@ void HeapRegion::print_on(outputStream* st) const { G1OffsetTableContigSpace::print_on(st); } -class VerifyLiveClosure: public OopClosure { -private: +class G1VerificationClosure : public OopClosure { +protected: G1CollectedHeap* _g1h; CardTableModRefBS* _bs; oop _containing_obj; @@ -651,7 +651,7 @@ public: // _vo == UsePrevMarking -> use "prev" marking information, // _vo == UseNextMarking -> use "next" marking information, // _vo == UseMarkWord -> use mark word from object header. - VerifyLiveClosure(G1CollectedHeap* g1h, VerifyOption vo) : + G1VerificationClosure(G1CollectedHeap* g1h, VerifyOption vo) : _g1h(g1h), _bs(NULL), _containing_obj(NULL), _failures(false), _n_failures(0), _vo(vo) { @@ -667,9 +667,6 @@ public: bool failures() { return _failures; } int n_failures() { return _n_failures; } - virtual void do_oop(narrowOop* p) { do_oop_work(p); } - virtual void do_oop( oop* p) { do_oop_work(p); } - void print_object(outputStream* out, oop obj) { #ifdef PRODUCT Klass* k = obj->klass(); @@ -679,19 +676,31 @@ public: obj->print_on(out); #endif // PRODUCT } +}; + +class VerifyLiveClosure : public G1VerificationClosure { +public: + VerifyLiveClosure(G1CollectedHeap* g1h, VerifyOption vo) : G1VerificationClosure(g1h, vo) {} + virtual void do_oop(narrowOop* p) { do_oop_work(p); } + virtual void do_oop(oop* p) { do_oop_work(p); } template void do_oop_work(T* p) { assert(_containing_obj != NULL, "Precondition"); assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo), - "Precondition"); + "Precondition"); + verify_liveness(p); + } + + template + void verify_liveness(T* p) { T heap_oop = oopDesc::load_heap_oop(p); if (!oopDesc::is_null(heap_oop)) { oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); bool failed = false; if (!_g1h->is_in_closed_subset(obj) || _g1h->is_obj_dead_cond(obj, _vo)) { MutexLockerEx x(ParGCRareEvent_lock, - Mutex::_no_safepoint_check_flag); + Mutex::_no_safepoint_check_flag); if (!_failures) { gclog_or_tty->cr(); @@ -727,50 +736,71 @@ public: failed = true; _n_failures++; } + } + } +}; - if (!_g1h->full_collection() || G1VerifyRSetsDuringFullGC) { - HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p); - HeapRegion* to = _g1h->heap_region_containing(obj); - if (from != NULL && to != NULL && - from != to && - !to->isHumongous()) { - jbyte cv_obj = *_bs->byte_for_const(_containing_obj); - jbyte cv_field = *_bs->byte_for_const(p); - const jbyte dirty = CardTableModRefBS::dirty_card_val(); - - bool is_bad = !(from->is_young() - || to->rem_set()->contains_reference(p) - || !G1HRRSFlushLogBuffersOnVerify && // buffers were not flushed - (_containing_obj->is_objArray() ? - cv_field == dirty - : cv_obj == dirty || cv_field == dirty)); - if (is_bad) { - MutexLockerEx x(ParGCRareEvent_lock, - Mutex::_no_safepoint_check_flag); - - if (!_failures) { - gclog_or_tty->cr(); - gclog_or_tty->print_cr("----------"); - } - gclog_or_tty->print_cr("Missing rem set entry:"); - gclog_or_tty->print_cr("Field "PTR_FORMAT" " - "of obj "PTR_FORMAT", " - "in region "HR_FORMAT, - p, (void*) _containing_obj, - HR_FORMAT_PARAMS(from)); - _containing_obj->print_on(gclog_or_tty); - gclog_or_tty->print_cr("points to obj "PTR_FORMAT" " - "in region "HR_FORMAT, - (void*) obj, - HR_FORMAT_PARAMS(to)); - obj->print_on(gclog_or_tty); - gclog_or_tty->print_cr("Obj head CTE = %d, field CTE = %d.", - cv_obj, cv_field); +class VerifyRemSetClosure : public G1VerificationClosure { +public: + VerifyRemSetClosure(G1CollectedHeap* g1h, VerifyOption vo) : G1VerificationClosure(g1h, vo) {} + virtual void do_oop(narrowOop* p) { do_oop_work(p); } + virtual void do_oop(oop* p) { do_oop_work(p); } + + template + void do_oop_work(T* p) { + assert(_containing_obj != NULL, "Precondition"); + assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo), + "Precondition"); + verify_remembered_set(p); + } + + template + void verify_remembered_set(T* p) { + T heap_oop = oopDesc::load_heap_oop(p); + if (!oopDesc::is_null(heap_oop)) { + oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); + bool failed = false; + HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p); + HeapRegion* to = _g1h->heap_region_containing(obj); + if (from != NULL && to != NULL && + from != to && + !to->isHumongous()) { + jbyte cv_obj = *_bs->byte_for_const(_containing_obj); + jbyte cv_field = *_bs->byte_for_const(p); + const jbyte dirty = CardTableModRefBS::dirty_card_val(); + + bool is_bad = !(from->is_young() + || to->rem_set()->contains_reference(p) + || !G1HRRSFlushLogBuffersOnVerify && // buffers were not flushed + (_containing_obj->is_objArray() ? + cv_field == dirty + : cv_obj == dirty || cv_field == dirty)); + if (is_bad) { + MutexLockerEx x(ParGCRareEvent_lock, + Mutex::_no_safepoint_check_flag); + + if (!_failures) { + gclog_or_tty->cr(); gclog_or_tty->print_cr("----------"); - gclog_or_tty->flush(); - _failures = true; - if (!failed) _n_failures++; } + gclog_or_tty->print_cr("Missing rem set entry:"); + gclog_or_tty->print_cr("Field "PTR_FORMAT" " + "of obj "PTR_FORMAT", " + "in region "HR_FORMAT, + p, (void*) _containing_obj, + HR_FORMAT_PARAMS(from)); + _containing_obj->print_on(gclog_or_tty); + gclog_or_tty->print_cr("points to obj "PTR_FORMAT" " + "in region "HR_FORMAT, + (void*) obj, + HR_FORMAT_PARAMS(to)); + obj->print_on(gclog_or_tty); + gclog_or_tty->print_cr("Obj head CTE = %d, field CTE = %d.", + cv_obj, cv_field); + gclog_or_tty->print_cr("----------"); + gclog_or_tty->flush(); + _failures = true; + if (!failed) _n_failures++; } } } @@ -787,6 +817,7 @@ void HeapRegion::verify(VerifyOption vo, HeapWord* p = bottom(); HeapWord* prev_p = NULL; VerifyLiveClosure vl_cl(g1, vo); + VerifyRemSetClosure vr_cl(g1, vo); bool is_humongous = isHumongous(); bool do_bot_verify = !is_young(); size_t object_num = 0; @@ -832,7 +863,23 @@ void HeapRegion::verify(VerifyOption vo, return; } else { vl_cl.set_containing_obj(obj); - obj->oop_iterate_no_header(&vl_cl); + if (!g1->full_collection() || G1VerifyRSetsDuringFullGC) { + // verify liveness and rem_set + vr_cl.set_containing_obj(obj); + G1Mux2Closure mux(&vl_cl, &vr_cl); + obj->oop_iterate_no_header(&mux); + + if (vr_cl.failures()) { + *failures = true; + } + if (G1MaxVerifyFailures >= 0 && + vr_cl.n_failures() >= G1MaxVerifyFailures) { + return; + } + } else { + // verify only liveness + obj->oop_iterate_no_header(&vl_cl); + } if (vl_cl.failures()) { *failures = true; } @@ -842,7 +889,7 @@ void HeapRegion::verify(VerifyOption vo, } } } else { - gclog_or_tty->print_cr(PTR_FORMAT" no an oop", (void *)obj); + gclog_or_tty->print_cr(PTR_FORMAT" not an oop", (void *)obj); *failures = true; return; } @@ -930,6 +977,46 @@ void HeapRegion::verify() const { verify(VerifyOption_G1UsePrevMarking, /* failures */ &dummy); } +void HeapRegion::verify_rem_set(VerifyOption vo, bool* failures) const { + G1CollectedHeap* g1 = G1CollectedHeap::heap(); + *failures = false; + HeapWord* p = bottom(); + HeapWord* prev_p = NULL; + VerifyRemSetClosure vr_cl(g1, vo); + while (p < top()) { + oop obj = oop(p); + size_t obj_size = block_size(p); + + if (!g1->is_obj_dead_cond(obj, this, vo)) { + if (obj->is_oop()) { + vr_cl.set_containing_obj(obj); + obj->oop_iterate_no_header(&vr_cl); + + if (vr_cl.failures()) { + *failures = true; + } + if (G1MaxVerifyFailures >= 0 && + vr_cl.n_failures() >= G1MaxVerifyFailures) { + return; + } + } else { + gclog_or_tty->print_cr(PTR_FORMAT " not an oop", p2i(obj)); + *failures = true; + return; + } + } + + prev_p = p; + p += obj_size; + } +} + +void HeapRegion::verify_rem_set() const { + bool failures = false; + verify_rem_set(VerifyOption_G1UsePrevMarking, &failures); + guarantee(!failures, "HeapRegion RemSet verification failed"); +} + // G1OffsetTableContigSpace code; copied from space.cpp. Hope this can go // away eventually. diff --git a/src/share/vm/gc_implementation/g1/heapRegion.hpp b/src/share/vm/gc_implementation/g1/heapRegion.hpp index 80ba22313..e62a2abbc 100644 --- a/src/share/vm/gc_implementation/g1/heapRegion.hpp +++ b/src/share/vm/gc_implementation/g1/heapRegion.hpp @@ -779,6 +779,9 @@ class HeapRegion: public G1OffsetTableContigSpace { // Override; it uses the "prev" marking information virtual void verify() const; + + void verify_rem_set(VerifyOption vo, bool *failures) const; + void verify_rem_set() const; }; // HeapRegionClosure is used for iterating over regions. -- GitLab