# HG changeset patch # User tonyp # Date 1287178016 14400 # Node ID 9f4848ebbabd3e50442bec9eabcf1b85a34c25cd # Parent 35e4e086d5f56b4f1827126a894c85e274e15762 6992189: G1: inconsistent base used in sparse rem set iterator Summary: The remembered set iterator for sparse tables incorrectly assumes that index 0 corresponds to the bottom of the heap, not address 0 as it is the case. Reviewed-by: ysr, jmasa diff -r 35e4e086d5f5 -r 9f4848ebbabd src/share/vm/gc_implementation/g1/heapRegionRemSet.cpp --- a/src/share/vm/gc_implementation/g1/heapRegionRemSet.cpp Thu Oct 14 10:38:14 2010 -0400 +++ b/src/share/vm/gc_implementation/g1/heapRegionRemSet.cpp Fri Oct 15 17:26:56 2010 -0400 @@ -1159,9 +1159,7 @@ _hrrs(NULL), _g1h(G1CollectedHeap::heap()), _bosa(NULL), - _sparse_iter(size_t(G1CollectedHeap::heap()->reserved_region().start()) - >> CardTableModRefBS::card_shift) -{} + _sparse_iter() { } void HeapRegionRemSetIterator::initialize(const HeapRegionRemSet* hrrs) { _hrrs = hrrs; diff -r 35e4e086d5f5 -r 9f4848ebbabd src/share/vm/gc_implementation/g1/sparsePRT.cpp --- a/src/share/vm/gc_implementation/g1/sparsePRT.cpp Thu Oct 14 10:38:14 2010 -0400 +++ b/src/share/vm/gc_implementation/g1/sparsePRT.cpp Fri Oct 15 17:26:56 2010 -0400 @@ -323,10 +323,7 @@ } size_t /* RSHashTable:: */ RSHashTableIter::compute_card_ind(CardIdx_t ci) { - return - _heap_bot_card_ind - + (_rsht->entry(_bl_ind)->r_ind() * HeapRegion::CardsPerRegion) - + ci; + return (_rsht->entry(_bl_ind)->r_ind() * HeapRegion::CardsPerRegion) + ci; } bool /* RSHashTable:: */ RSHashTableIter::has_next(size_t& card_index) { diff -r 35e4e086d5f5 -r 9f4848ebbabd src/share/vm/gc_implementation/g1/sparsePRT.hpp --- a/src/share/vm/gc_implementation/g1/sparsePRT.hpp Thu Oct 14 10:38:14 2010 -0400 +++ b/src/share/vm/gc_implementation/g1/sparsePRT.hpp Fri Oct 15 17:26:56 2010 -0400 @@ -169,7 +169,6 @@ int _bl_ind; // [-1, 0.._rsht->_capacity) short _card_ind; // [0..SparsePRTEntry::cards_num()) RSHashTable* _rsht; - size_t _heap_bot_card_ind; // If the bucket list pointed to by _bl_ind contains a card, sets // _bl_ind to the index of that entry, and returns the card. @@ -183,13 +182,11 @@ size_t compute_card_ind(CardIdx_t ci); public: - RSHashTableIter(size_t heap_bot_card_ind) : + RSHashTableIter() : _tbl_ind(RSHashTable::NullEntry), _bl_ind(RSHashTable::NullEntry), _card_ind((SparsePRTEntry::cards_num() - 1)), - _rsht(NULL), - _heap_bot_card_ind(heap_bot_card_ind) - {} + _rsht(NULL) {} void init(RSHashTable* rsht) { _rsht = rsht; @@ -280,19 +277,12 @@ bool contains_card(RegionIdx_t region_id, CardIdx_t card_index) const { return _next->contains_card(region_id, card_index); } - -#if 0 - void verify_is_cleared(); - void print(); -#endif }; -class SparsePRTIter: public /* RSHashTable:: */RSHashTableIter { +class SparsePRTIter: public RSHashTableIter { public: - SparsePRTIter(size_t heap_bot_card_ind) : - /* RSHashTable:: */RSHashTableIter(heap_bot_card_ind) - {} + SparsePRTIter() : RSHashTableIter() { } void init(const SparsePRT* sprt) { RSHashTableIter::init(sprt->cur());