--- old/src/share/vm/gc_implementation/g1/heapRegion.cpp 2013-06-26 14:24:55.057473802 -0700 +++ new/src/share/vm/gc_implementation/g1/heapRegion.cpp 2013-06-26 14:24:54.846703252 -0700 @@ -23,6 +23,7 @@ */ #include "precompiled.hpp" +#include "code/nmethod.hpp" #include "gc_implementation/g1/g1BlockOffsetTable.inline.hpp" #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" #include "gc_implementation/g1/g1OopClosures.inline.hpp" @@ -50,144 +51,6 @@ OopClosure* oc) : _r_bottom(r->bottom()), _r_end(r->end()), _oc(oc) { } -class VerifyLiveClosure: public OopClosure { -private: - G1CollectedHeap* _g1h; - CardTableModRefBS* _bs; - oop _containing_obj; - bool _failures; - int _n_failures; - VerifyOption _vo; -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) : - _g1h(g1h), _bs(NULL), _containing_obj(NULL), - _failures(false), _n_failures(0), _vo(vo) - { - BarrierSet* bs = _g1h->barrier_set(); - if (bs->is_a(BarrierSet::CardTableModRef)) - _bs = (CardTableModRefBS*)bs; - } - - void set_containing_obj(oop obj) { - _containing_obj = obj; - } - - 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(); - const char* class_name = InstanceKlass::cast(k)->external_name(); - out->print_cr("class name %s", class_name); -#else // PRODUCT - obj->print_on(out); -#endif // PRODUCT - } - - template - void do_oop_work(T* p) { - assert(_containing_obj != NULL, "Precondition"); - assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo), - "Precondition"); - 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); - - if (!_failures) { - gclog_or_tty->print_cr(""); - gclog_or_tty->print_cr("----------"); - } - if (!_g1h->is_in_closed_subset(obj)) { - HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p); - gclog_or_tty->print_cr("Field "PTR_FORMAT - " of live obj "PTR_FORMAT" in region " - "["PTR_FORMAT", "PTR_FORMAT")", - p, (void*) _containing_obj, - from->bottom(), from->end()); - print_object(gclog_or_tty, _containing_obj); - gclog_or_tty->print_cr("points to obj "PTR_FORMAT" not in the heap", - (void*) obj); - } else { - HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p); - HeapRegion* to = _g1h->heap_region_containing((HeapWord*)obj); - gclog_or_tty->print_cr("Field "PTR_FORMAT - " of live obj "PTR_FORMAT" in region " - "["PTR_FORMAT", "PTR_FORMAT")", - p, (void*) _containing_obj, - from->bottom(), from->end()); - print_object(gclog_or_tty, _containing_obj); - gclog_or_tty->print_cr("points to dead obj "PTR_FORMAT" in region " - "["PTR_FORMAT", "PTR_FORMAT")", - (void*) obj, to->bottom(), to->end()); - print_object(gclog_or_tty, obj); - } - gclog_or_tty->print_cr("----------"); - gclog_or_tty->flush(); - _failures = true; - 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->print_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); - gclog_or_tty->print_cr("----------"); - gclog_or_tty->flush(); - _failures = true; - if (!failed) _n_failures++; - } - } - } - } - } -}; - template HeapWord* walk_mem_region_loop(ClosureType* cl, G1CollectedHeap* g1h, HeapRegion* hr, @@ -363,7 +226,7 @@ if (!par) { // If this is parallel, this will be done later. HeapRegionRemSet* hrrs = rem_set(); - if (hrrs != NULL) hrrs->clear(); + hrrs->clear(); _claimed = InitialClaimValue; } zero_marked_bytes(); @@ -500,6 +363,7 @@ _rem_set(NULL), _recorded_rs_length(0), _predicted_elapsed_time_ms(0), _predicted_bytes_to_copy(0) { + _rem_set = new HeapRegionRemSet(sharedOffsetArray, this); _orig_end = mr.end(); // Note that initialize() will set the start of the unmarked area of the // region. @@ -507,8 +371,6 @@ set_top(bottom()); set_saved_mark(); - _rem_set = new HeapRegionRemSet(sharedOffsetArray, this); - assert(HeapRegionRemSet::num_par_rem_sets() > 0, "Invariant."); } @@ -728,6 +590,160 @@ return NULL; } +// Code roots support + +void HeapRegion::add_strong_code_root(nmethod* nm) { + HeapRegionRemSet* hrrs = rem_set(); + hrrs->add_strong_code_root(nm); +} + +void HeapRegion::remove_strong_code_root(nmethod* nm) { + HeapRegionRemSet* hrrs = rem_set(); + hrrs->remove_strong_code_root(nm); +} + +void HeapRegion::migrate_strong_code_roots() { + assert(in_collection_set(), "only collection set regions"); + assert(!isHumongous(), "not humongous regions"); + + HeapRegionRemSet* hrrs = rem_set(); + hrrs->migrate_strong_code_roots(); +} + +void HeapRegion::strong_code_roots_do(CodeBlobClosure* blk) const { + HeapRegionRemSet* hrrs = rem_set(); + hrrs->strong_code_roots_do(blk); +} + +class VerifyStrongCodeRootOopClosure: public OopClosure { + const HeapRegion* _hr; + nmethod* _nm; + bool _failures; + bool _has_oops_in_region; + + template void do_oop_work(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); + + // Note: not all the oops embedded in the nmethod are in the + // current region. We only look at those which are. + if (_hr->is_in(obj)) { + // Object is in the region. Check that its less than top + if (_hr->top() <= (HeapWord*)obj) { + // Object is above top + gclog_or_tty->print_cr("Object "PTR_FORMAT" in region " + "["PTR_FORMAT", "PTR_FORMAT") is above " + "top "PTR_FORMAT, + obj, _hr->bottom(), _hr->end(), _hr->top()); + _failures = true; + return; + } + // Nmethod has at least one oop in the current region + _has_oops_in_region = true; + } + } + } + +public: + VerifyStrongCodeRootOopClosure(const HeapRegion* hr, nmethod* nm): + _hr(hr), _failures(false), _has_oops_in_region(false) {} + + void do_oop(narrowOop* p) { do_oop_work(p); } + void do_oop(oop* p) { do_oop_work(p); } + + bool failures() { return _failures; } + bool has_oops_in_region() { return _has_oops_in_region; } +}; + +class VerifyStrongCodeRootCodeBlobClosure: public CodeBlobClosure { + const HeapRegion* _hr; + bool _failures; +public: + VerifyStrongCodeRootCodeBlobClosure(const HeapRegion* hr) : + _hr(hr), _failures(false) {} + + void do_code_blob(CodeBlob* cb) { + nmethod* nm = (cb == NULL) ? NULL : cb->as_nmethod_or_null(); + if (nm != NULL) { + // Verify that the nemthod is live + if (!nm->is_alive()) { + gclog_or_tty->print_cr("region ["PTR_FORMAT","PTR_FORMAT"] has dead nmethod " + PTR_FORMAT" in its strong code roots", + _hr->bottom(), _hr->end(), nm); + _failures = true; + } else { + VerifyStrongCodeRootOopClosure oop_cl(_hr, nm); + nm->oops_do(&oop_cl); + if (!oop_cl.has_oops_in_region()) { + gclog_or_tty->print_cr("region ["PTR_FORMAT","PTR_FORMAT"] has nmethod " + PTR_FORMAT" in its strong code roots " + "with no pointers into region", + _hr->bottom(), _hr->end(), nm); + _failures = true; + } else if (oop_cl.failures()) { + gclog_or_tty->print_cr("region ["PTR_FORMAT","PTR_FORMAT"] has other " + "failures for nmethod "PTR_FORMAT, + _hr->bottom(), _hr->end(), nm); + _failures = true; + } + } + } + } + + bool failures() { return _failures; } +}; + +void HeapRegion::verify_strong_code_roots(VerifyOption vo, bool* failures) const { + if (!G1VerifyHeapRegionCodeRoots) { + // We're not verifying code roots. + return; + } + if (vo == VerifyOption_G1UseMarkWord) { + // Marking verification during a full GC is performed after class + // unloading, code cache unloading, etc so the strong code roots + // attached to each heap region are in an inconsistent state. They won't + // be consistent until the strong code roots are rebuilt after the + // actual GC. Skip verifying the strong code roots in this particular + // time. + assert(VerifyDuringGC, "only way to get here"); + return; + } + + HeapRegionRemSet* hrrs = rem_set(); + int strong_code_roots_length = hrrs->strong_code_roots_list_length(); + + // if this region is empty then there should be no entries + // on its strong code root list + if (is_empty()) { + if (strong_code_roots_length > 0) { + gclog_or_tty->print_cr("region ["PTR_FORMAT","PTR_FORMAT"] is empty " + "but has "INT32_FORMAT" code root entries", + bottom(), end(), strong_code_roots_length); + *failures = true; + } + return; + } + + // An H-region should have an empty strong code root list + if (isHumongous()) { + if (strong_code_roots_length > 0) { + gclog_or_tty->print_cr("region ["PTR_FORMAT","PTR_FORMAT"] is humongous " + "but has "INT32_FORMAT" code root entries", + bottom(), end(), strong_code_roots_length); + *failures = true; + } + return; + } + + VerifyStrongCodeRootCodeBlobClosure cb_cl(this); + strong_code_roots_do(&cb_cl); + + if (cb_cl.failures()) { + *failures = true; + } +} + void HeapRegion::print() const { print_on(gclog_or_tty); } void HeapRegion::print_on(outputStream* st) const { if (isHumongous()) { @@ -756,10 +772,143 @@ G1OffsetTableContigSpace::print_on(st); } -void HeapRegion::verify() const { - bool dummy = false; - verify(VerifyOption_G1UsePrevMarking, /* failures */ &dummy); -} +class VerifyLiveClosure: public OopClosure { +private: + G1CollectedHeap* _g1h; + CardTableModRefBS* _bs; + oop _containing_obj; + bool _failures; + int _n_failures; + VerifyOption _vo; +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) : + _g1h(g1h), _bs(NULL), _containing_obj(NULL), + _failures(false), _n_failures(0), _vo(vo) + { + BarrierSet* bs = _g1h->barrier_set(); + if (bs->is_a(BarrierSet::CardTableModRef)) + _bs = (CardTableModRefBS*)bs; + } + + void set_containing_obj(oop obj) { + _containing_obj = obj; + } + + 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(); + const char* class_name = InstanceKlass::cast(k)->external_name(); + out->print_cr("class name %s", class_name); +#else // PRODUCT + obj->print_on(out); +#endif // PRODUCT + } + + template + void do_oop_work(T* p) { + assert(_containing_obj != NULL, "Precondition"); + assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo), + "Precondition"); + 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); + + if (!_failures) { + gclog_or_tty->print_cr(""); + gclog_or_tty->print_cr("----------"); + } + if (!_g1h->is_in_closed_subset(obj)) { + HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p); + gclog_or_tty->print_cr("Field "PTR_FORMAT + " of live obj "PTR_FORMAT" in region " + "["PTR_FORMAT", "PTR_FORMAT")", + p, (void*) _containing_obj, + from->bottom(), from->end()); + print_object(gclog_or_tty, _containing_obj); + gclog_or_tty->print_cr("points to obj "PTR_FORMAT" not in the heap", + (void*) obj); + } else { + HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p); + HeapRegion* to = _g1h->heap_region_containing((HeapWord*)obj); + gclog_or_tty->print_cr("Field "PTR_FORMAT + " of live obj "PTR_FORMAT" in region " + "["PTR_FORMAT", "PTR_FORMAT")", + p, (void*) _containing_obj, + from->bottom(), from->end()); + print_object(gclog_or_tty, _containing_obj); + gclog_or_tty->print_cr("points to dead obj "PTR_FORMAT" in region " + "["PTR_FORMAT", "PTR_FORMAT")", + (void*) obj, to->bottom(), to->end()); + print_object(gclog_or_tty, obj); + } + gclog_or_tty->print_cr("----------"); + gclog_or_tty->flush(); + _failures = true; + 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->print_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); + gclog_or_tty->print_cr("----------"); + gclog_or_tty->flush(); + _failures = true; + if (!failed) _n_failures++; + } + } + } + } + } +}; // This really ought to be commoned up into OffsetTableContigSpace somehow. // We would need a mechanism to make that code skip dead objects. @@ -899,6 +1048,13 @@ *failures = true; return; } + + verify_strong_code_roots(vo, failures); +} + +void HeapRegion::verify() const { + bool dummy = false; + verify(VerifyOption_G1UsePrevMarking, /* failures */ &dummy); } // G1OffsetTableContigSpace code; copied from space.cpp. Hope this can go