Mercurial > hg > truffle
diff src/share/vm/gc_implementation/g1/heapRegionRemSet.cpp @ 342:37f87013dfd8
6711316: Open source the Garbage-First garbage collector
Summary: First mercurial integration of the code for the Garbage-First garbage collector.
Reviewed-by: apetrusenko, iveresov, jmasa, sgoldman, tonyp, ysr
author | ysr |
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date | Thu, 05 Jun 2008 15:57:56 -0700 |
parents | |
children | 2494ab195856 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/gc_implementation/g1/heapRegionRemSet.cpp Thu Jun 05 15:57:56 2008 -0700 @@ -0,0 +1,1443 @@ +/* + * Copyright 2001-2007 Sun Microsystems, Inc. All Rights Reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + */ + +#include "incls/_precompiled.incl" +#include "incls/_heapRegionRemSet.cpp.incl" + +#define HRRS_VERBOSE 0 + +#define PRT_COUNT_OCCUPIED 1 + +// OtherRegionsTable + +class PerRegionTable: public CHeapObj { + friend class OtherRegionsTable; + friend class HeapRegionRemSetIterator; + + HeapRegion* _hr; + BitMap _bm; +#if PRT_COUNT_OCCUPIED + jint _occupied; +#endif + PerRegionTable* _next_free; + + PerRegionTable* next_free() { return _next_free; } + void set_next_free(PerRegionTable* prt) { _next_free = prt; } + + + static PerRegionTable* _free_list; + +#ifdef _MSC_VER + // For some reason even though the classes are marked as friend they are unable + // to access CardsPerRegion when private/protected. Only the windows c++ compiler + // says this Sun CC and linux gcc don't have a problem with access when private + + public: + +#endif // _MSC_VER + + enum SomePrivateConstants { + CardsPerRegion = HeapRegion::GrainBytes >> CardTableModRefBS::card_shift + }; + +protected: + // We need access in order to union things into the base table. + BitMap* bm() { return &_bm; } + + void recount_occupied() { + _occupied = (jint) bm()->count_one_bits(); + } + + PerRegionTable(HeapRegion* hr) : + _hr(hr), +#if PRT_COUNT_OCCUPIED + _occupied(0), +#endif + _bm(CardsPerRegion, false /* in-resource-area */) + {} + + static void free(PerRegionTable* prt) { + while (true) { + PerRegionTable* fl = _free_list; + prt->set_next_free(fl); + PerRegionTable* res = + (PerRegionTable*) + Atomic::cmpxchg_ptr(prt, &_free_list, fl); + if (res == fl) return; + } + ShouldNotReachHere(); + } + + static PerRegionTable* alloc(HeapRegion* hr) { + PerRegionTable* fl = _free_list; + while (fl != NULL) { + PerRegionTable* nxt = fl->next_free(); + PerRegionTable* res = + (PerRegionTable*) + Atomic::cmpxchg_ptr(nxt, &_free_list, fl); + if (res == fl) { + fl->init(hr); + return fl; + } else { + fl = _free_list; + } + } + assert(fl == NULL, "Loop condition."); + return new PerRegionTable(hr); + } + + void add_card_work(short from_card, bool par) { + if (!_bm.at(from_card)) { + if (par) { + if (_bm.par_at_put(from_card, 1)) { +#if PRT_COUNT_OCCUPIED + Atomic::inc(&_occupied); +#endif + } + } else { + _bm.at_put(from_card, 1); +#if PRT_COUNT_OCCUPIED + _occupied++; +#endif + } + } + } + + void add_reference_work(oop* from, bool par) { + // Must make this robust in case "from" is not in "_hr", because of + // concurrency. + +#if HRRS_VERBOSE + gclog_or_tty->print_cr(" PRT::Add_reference_work(" PTR_FORMAT "->" PTR_FORMAT").", + from, *from); +#endif + + HeapRegion* loc_hr = hr(); + // If the test below fails, then this table was reused concurrently + // with this operation. This is OK, since the old table was coarsened, + // and adding a bit to the new table is never incorrect. + if (loc_hr->is_in_reserved(from)) { + size_t hw_offset = pointer_delta((HeapWord*)from, loc_hr->bottom()); + size_t from_card = + hw_offset >> + (CardTableModRefBS::card_shift - LogHeapWordSize); + + add_card_work((short) from_card, par); + } + } + +public: + + HeapRegion* hr() const { return _hr; } + +#if PRT_COUNT_OCCUPIED + jint occupied() const { + // Overkill, but if we ever need it... + // guarantee(_occupied == _bm.count_one_bits(), "Check"); + return _occupied; + } +#else + jint occupied() const { + return _bm.count_one_bits(); + } +#endif + + void init(HeapRegion* hr) { + _hr = hr; +#if PRT_COUNT_OCCUPIED + _occupied = 0; +#endif + _bm.clear(); + } + + void add_reference(oop* from) { + add_reference_work(from, /*parallel*/ true); + } + + void seq_add_reference(oop* from) { + add_reference_work(from, /*parallel*/ false); + } + + void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) { + HeapWord* hr_bot = hr()->bottom(); + int hr_first_card_index = ctbs->index_for(hr_bot); + bm()->set_intersection_at_offset(*card_bm, hr_first_card_index); +#if PRT_COUNT_OCCUPIED + recount_occupied(); +#endif + } + + void add_card(short from_card_index) { + add_card_work(from_card_index, /*parallel*/ true); + } + + void seq_add_card(short from_card_index) { + add_card_work(from_card_index, /*parallel*/ false); + } + + // (Destructively) union the bitmap of the current table into the given + // bitmap (which is assumed to be of the same size.) + void union_bitmap_into(BitMap* bm) { + bm->set_union(_bm); + } + + // Mem size in bytes. + size_t mem_size() const { + return sizeof(this) + _bm.size_in_words() * HeapWordSize; + } + + static size_t fl_mem_size() { + PerRegionTable* cur = _free_list; + size_t res = 0; + while (cur != NULL) { + res += sizeof(PerRegionTable); + cur = cur->next_free(); + } + return res; + } + + // Requires "from" to be in "hr()". + bool contains_reference(oop* from) const { + assert(hr()->is_in_reserved(from), "Precondition."); + size_t card_ind = pointer_delta(from, hr()->bottom(), + CardTableModRefBS::card_size); + return _bm.at(card_ind); + } +}; + +PerRegionTable* PerRegionTable::_free_list = NULL; + + +#define COUNT_PAR_EXPANDS 0 + +#if COUNT_PAR_EXPANDS +static jint n_par_expands = 0; +static jint n_par_contracts = 0; +static jint par_expand_list_len = 0; +static jint max_par_expand_list_len = 0; + +static void print_par_expand() { + Atomic::inc(&n_par_expands); + Atomic::inc(&par_expand_list_len); + if (par_expand_list_len > max_par_expand_list_len) { + max_par_expand_list_len = par_expand_list_len; + } + if ((n_par_expands % 10) == 0) { + gclog_or_tty->print_cr("\n\n%d par expands: %d contracts, " + "len = %d, max_len = %d\n.", + n_par_expands, n_par_contracts, par_expand_list_len, + max_par_expand_list_len); + } +} +#endif + +class PosParPRT: public PerRegionTable { + PerRegionTable** _par_tables; + + enum SomePrivateConstants { + ReserveParTableExpansion = 1 + }; + + void par_expand() { + int n = HeapRegionRemSet::num_par_rem_sets()-1; + if (n <= 0) return; + if (_par_tables == NULL) { + PerRegionTable* res = + (PerRegionTable*) + Atomic::cmpxchg_ptr((PerRegionTable*)ReserveParTableExpansion, + &_par_tables, NULL); + if (res != NULL) return; + // Otherwise, we reserved the right to do the expansion. + + PerRegionTable** ptables = NEW_C_HEAP_ARRAY(PerRegionTable*, n); + for (int i = 0; i < n; i++) { + PerRegionTable* ptable = PerRegionTable::alloc(hr()); + ptables[i] = ptable; + } + // Here we do not need an atomic. + _par_tables = ptables; +#if COUNT_PAR_EXPANDS + print_par_expand(); +#endif + // We must put this table on the expanded list. + PosParPRT* exp_head = _par_expanded_list; + while (true) { + set_next_par_expanded(exp_head); + PosParPRT* res = + (PosParPRT*) + Atomic::cmpxchg_ptr(this, &_par_expanded_list, exp_head); + if (res == exp_head) return; + // Otherwise. + exp_head = res; + } + ShouldNotReachHere(); + } + } + + void par_contract() { + assert(_par_tables != NULL, "Precondition."); + int n = HeapRegionRemSet::num_par_rem_sets()-1; + for (int i = 0; i < n; i++) { + _par_tables[i]->union_bitmap_into(bm()); + PerRegionTable::free(_par_tables[i]); + _par_tables[i] = NULL; + } +#if PRT_COUNT_OCCUPIED + // We must recount the "occupied." + recount_occupied(); +#endif + FREE_C_HEAP_ARRAY(PerRegionTable*, _par_tables); + _par_tables = NULL; +#if COUNT_PAR_EXPANDS + Atomic::inc(&n_par_contracts); + Atomic::dec(&par_expand_list_len); +#endif + } + + static PerRegionTable** _par_table_fl; + + PosParPRT* _next; + + static PosParPRT* _free_list; + + PerRegionTable** par_tables() const { + assert(uintptr_t(NULL) == 0, "Assumption."); + if (uintptr_t(_par_tables) <= ReserveParTableExpansion) + return NULL; + else + return _par_tables; + } + + PosParPRT* _next_par_expanded; + PosParPRT* next_par_expanded() { return _next_par_expanded; } + void set_next_par_expanded(PosParPRT* ppprt) { _next_par_expanded = ppprt; } + static PosParPRT* _par_expanded_list; + +public: + + PosParPRT(HeapRegion* hr) : PerRegionTable(hr), _par_tables(NULL) {} + + jint occupied() const { + jint res = PerRegionTable::occupied(); + if (par_tables() != NULL) { + for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) { + res += par_tables()[i]->occupied(); + } + } + return res; + } + + void init(HeapRegion* hr) { + PerRegionTable::init(hr); + _next = NULL; + if (par_tables() != NULL) { + for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) { + par_tables()[i]->init(hr); + } + } + } + + static void free(PosParPRT* prt) { + while (true) { + PosParPRT* fl = _free_list; + prt->set_next(fl); + PosParPRT* res = + (PosParPRT*) + Atomic::cmpxchg_ptr(prt, &_free_list, fl); + if (res == fl) return; + } + ShouldNotReachHere(); + } + + static PosParPRT* alloc(HeapRegion* hr) { + PosParPRT* fl = _free_list; + while (fl != NULL) { + PosParPRT* nxt = fl->next(); + PosParPRT* res = + (PosParPRT*) + Atomic::cmpxchg_ptr(nxt, &_free_list, fl); + if (res == fl) { + fl->init(hr); + return fl; + } else { + fl = _free_list; + } + } + assert(fl == NULL, "Loop condition."); + return new PosParPRT(hr); + } + + PosParPRT* next() const { return _next; } + void set_next(PosParPRT* nxt) { _next = nxt; } + PosParPRT** next_addr() { return &_next; } + + void add_reference(oop* from, int tid) { + // Expand if necessary. + PerRegionTable** pt = par_tables(); + if (par_tables() == NULL && tid > 0 && hr()->is_gc_alloc_region()) { + par_expand(); + pt = par_tables(); + } + if (pt != NULL) { + // We always have to assume that mods to table 0 are in parallel, + // because of the claiming scheme in parallel expansion. A thread + // with tid != 0 that finds the table to be NULL, but doesn't succeed + // in claiming the right of expanding it, will end up in the else + // clause of the above if test. That thread could be delayed, and a + // thread 0 add reference could see the table expanded, and come + // here. Both threads would be adding in parallel. But we get to + // not use atomics for tids > 0. + if (tid == 0) { + PerRegionTable::add_reference(from); + } else { + pt[tid-1]->seq_add_reference(from); + } + } else { + // Not expanded -- add to the base table. + PerRegionTable::add_reference(from); + } + } + + void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) { + assert(_par_tables == NULL, "Precondition"); + PerRegionTable::scrub(ctbs, card_bm); + } + + size_t mem_size() const { + size_t res = + PerRegionTable::mem_size() + sizeof(this) - sizeof(PerRegionTable); + if (_par_tables != NULL) { + for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) { + res += _par_tables[i]->mem_size(); + } + } + return res; + } + + static size_t fl_mem_size() { + PosParPRT* cur = _free_list; + size_t res = 0; + while (cur != NULL) { + res += sizeof(PosParPRT); + cur = cur->next(); + } + return res; + } + + bool contains_reference(oop* from) const { + if (PerRegionTable::contains_reference(from)) return true; + if (_par_tables != NULL) { + for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) { + if (_par_tables[i]->contains_reference(from)) return true; + } + } + return false; + } + + static void par_contract_all(); + +}; + +void PosParPRT::par_contract_all() { + PosParPRT* hd = _par_expanded_list; + while (hd != NULL) { + PosParPRT* nxt = hd->next_par_expanded(); + PosParPRT* res = + (PosParPRT*) + Atomic::cmpxchg_ptr(nxt, &_par_expanded_list, hd); + if (res == hd) { + // We claimed the right to contract this table. + hd->set_next_par_expanded(NULL); + hd->par_contract(); + hd = _par_expanded_list; + } else { + hd = res; + } + } +} + +PosParPRT* PosParPRT::_free_list = NULL; +PosParPRT* PosParPRT::_par_expanded_list = NULL; + +jint OtherRegionsTable::_cache_probes = 0; +jint OtherRegionsTable::_cache_hits = 0; + +size_t OtherRegionsTable::_max_fine_entries = 0; +size_t OtherRegionsTable::_mod_max_fine_entries_mask = 0; +#if SAMPLE_FOR_EVICTION +size_t OtherRegionsTable::_fine_eviction_stride = 0; +size_t OtherRegionsTable::_fine_eviction_sample_size = 0; +#endif + +OtherRegionsTable::OtherRegionsTable(HeapRegion* hr) : + _g1h(G1CollectedHeap::heap()), + _m(Mutex::leaf, "An OtherRegionsTable lock", true), + _hr(hr), + _coarse_map(G1CollectedHeap::heap()->max_regions(), + false /* in-resource-area */), + _fine_grain_regions(NULL), + _n_fine_entries(0), _n_coarse_entries(0), +#if SAMPLE_FOR_EVICTION + _fine_eviction_start(0), +#endif + _sparse_table(hr) +{ + typedef PosParPRT* PosParPRTPtr; + if (_max_fine_entries == 0) { + assert(_mod_max_fine_entries_mask == 0, "Both or none."); + _max_fine_entries = (1 << G1LogRSRegionEntries); + _mod_max_fine_entries_mask = _max_fine_entries - 1; +#if SAMPLE_FOR_EVICTION + assert(_fine_eviction_sample_size == 0 + && _fine_eviction_stride == 0, "All init at same time."); + _fine_eviction_sample_size = MAX2((size_t)4, (size_t)G1LogRSRegionEntries); + _fine_eviction_stride = _max_fine_entries / _fine_eviction_sample_size; +#endif + } + _fine_grain_regions = new PosParPRTPtr[_max_fine_entries]; + if (_fine_grain_regions == NULL) + vm_exit_out_of_memory(sizeof(void*)*_max_fine_entries, + "Failed to allocate _fine_grain_entries."); + for (size_t i = 0; i < _max_fine_entries; i++) { + _fine_grain_regions[i] = NULL; + } +} + +int** OtherRegionsTable::_from_card_cache = NULL; +size_t OtherRegionsTable::_from_card_cache_max_regions = 0; +size_t OtherRegionsTable::_from_card_cache_mem_size = 0; + +void OtherRegionsTable::init_from_card_cache(size_t max_regions) { + _from_card_cache_max_regions = max_regions; + + int n_par_rs = HeapRegionRemSet::num_par_rem_sets(); + _from_card_cache = NEW_C_HEAP_ARRAY(int*, n_par_rs); + for (int i = 0; i < n_par_rs; i++) { + _from_card_cache[i] = NEW_C_HEAP_ARRAY(int, max_regions); + for (size_t j = 0; j < max_regions; j++) { + _from_card_cache[i][j] = -1; // An invalid value. + } + } + _from_card_cache_mem_size = n_par_rs * max_regions * sizeof(int); +} + +void OtherRegionsTable::shrink_from_card_cache(size_t new_n_regs) { + for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) { + assert(new_n_regs <= _from_card_cache_max_regions, "Must be within max."); + for (size_t j = new_n_regs; j < _from_card_cache_max_regions; j++) { + _from_card_cache[i][j] = -1; // An invalid value. + } + } +} + +#ifndef PRODUCT +void OtherRegionsTable::print_from_card_cache() { + for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) { + for (size_t j = 0; j < _from_card_cache_max_regions; j++) { + gclog_or_tty->print_cr("_from_card_cache[%d][%d] = %d.", + i, j, _from_card_cache[i][j]); + } + } +} +#endif + +void OtherRegionsTable::add_reference(oop* from, int tid) { + size_t cur_hrs_ind = hr()->hrs_index(); + +#if HRRS_VERBOSE + gclog_or_tty->print_cr("ORT::add_reference_work(" PTR_FORMAT "->" PTR_FORMAT ").", + from, *from); +#endif + + int from_card = (int)(uintptr_t(from) >> CardTableModRefBS::card_shift); + +#if HRRS_VERBOSE + gclog_or_tty->print_cr("Table for [" PTR_FORMAT "...): card %d (cache = %d)", + hr()->bottom(), from_card, + _from_card_cache[tid][cur_hrs_ind]); +#endif + +#define COUNT_CACHE 0 +#if COUNT_CACHE + jint p = Atomic::add(1, &_cache_probes); + if ((p % 10000) == 0) { + jint hits = _cache_hits; + gclog_or_tty->print_cr("%d/%d = %5.2f%% RS cache hits.", + _cache_hits, p, 100.0* (float)hits/(float)p); + } +#endif + if (from_card == _from_card_cache[tid][cur_hrs_ind]) { +#if HRRS_VERBOSE + gclog_or_tty->print_cr(" from-card cache hit."); +#endif +#if COUNT_CACHE + Atomic::inc(&_cache_hits); +#endif + assert(contains_reference(from), "We just added it!"); + return; + } else { + _from_card_cache[tid][cur_hrs_ind] = from_card; + } + + // Note that this may be a continued H region. + HeapRegion* from_hr = _g1h->heap_region_containing_raw(from); + size_t from_hrs_ind = (size_t)from_hr->hrs_index(); + + // If the region is already coarsened, return. + if (_coarse_map.at(from_hrs_ind)) { +#if HRRS_VERBOSE + gclog_or_tty->print_cr(" coarse map hit."); +#endif + assert(contains_reference(from), "We just added it!"); + return; + } + + // Otherwise find a per-region table to add it to. + size_t ind = from_hrs_ind & _mod_max_fine_entries_mask; + PosParPRT* prt = find_region_table(ind, from_hr); + if (prt == NULL) { + MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag); + // Confirm that it's really not there... + prt = find_region_table(ind, from_hr); + if (prt == NULL) { + + uintptr_t from_hr_bot_card_index = + uintptr_t(from_hr->bottom()) + >> CardTableModRefBS::card_shift; + int card_index = from_card - from_hr_bot_card_index; + assert(0 <= card_index && card_index < PosParPRT::CardsPerRegion, + "Must be in range."); + if (G1HRRSUseSparseTable && + _sparse_table.add_card((short) from_hrs_ind, card_index)) { + if (G1RecordHRRSOops) { + HeapRegionRemSet::record(hr(), from); +#if HRRS_VERBOSE + gclog_or_tty->print(" Added card " PTR_FORMAT " to region " + "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n", + align_size_down(uintptr_t(from), + CardTableModRefBS::card_size), + hr()->bottom(), from); +#endif + } +#if HRRS_VERBOSE + gclog_or_tty->print_cr(" added card to sparse table."); +#endif + assert(contains_reference_locked(from), "We just added it!"); + return; + } else { +#if HRRS_VERBOSE + gclog_or_tty->print_cr(" [tid %d] sparse table entry " + "overflow(f: %d, t: %d)", + tid, from_hrs_ind, cur_hrs_ind); +#endif + } + + // Otherwise, transfer from sparse to fine-grain. + short cards[SparsePRTEntry::CardsPerEntry]; + if (G1HRRSUseSparseTable) { + bool res = _sparse_table.get_cards((short) from_hrs_ind, &cards[0]); + assert(res, "There should have been an entry"); + } + + if (_n_fine_entries == _max_fine_entries) { + prt = delete_region_table(); + } else { + prt = PosParPRT::alloc(from_hr); + } + prt->init(from_hr); + // Record the outgoing pointer in the from_region's outgoing bitmap. + from_hr->rem_set()->add_outgoing_reference(hr()); + + PosParPRT* first_prt = _fine_grain_regions[ind]; + prt->set_next(first_prt); // XXX Maybe move to init? + _fine_grain_regions[ind] = prt; + _n_fine_entries++; + + // Add in the cards from the sparse table. + if (G1HRRSUseSparseTable) { + for (int i = 0; i < SparsePRTEntry::CardsPerEntry; i++) { + short c = cards[i]; + if (c != SparsePRTEntry::NullEntry) { + prt->add_card(c); + } + } + // Now we can delete the sparse entry. + bool res = _sparse_table.delete_entry((short) from_hrs_ind); + assert(res, "It should have been there."); + } + } + assert(prt != NULL && prt->hr() == from_hr, "consequence"); + } + // Note that we can't assert "prt->hr() == from_hr", because of the + // possibility of concurrent reuse. But see head comment of + // OtherRegionsTable for why this is OK. + assert(prt != NULL, "Inv"); + + prt->add_reference(from, tid); + if (G1RecordHRRSOops) { + HeapRegionRemSet::record(hr(), from); +#if HRRS_VERBOSE + gclog_or_tty->print("Added card " PTR_FORMAT " to region " + "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n", + align_size_down(uintptr_t(from), + CardTableModRefBS::card_size), + hr()->bottom(), from); +#endif + } + assert(contains_reference(from), "We just added it!"); +} + +PosParPRT* +OtherRegionsTable::find_region_table(size_t ind, HeapRegion* hr) const { + assert(0 <= ind && ind < _max_fine_entries, "Preconditions."); + PosParPRT* prt = _fine_grain_regions[ind]; + while (prt != NULL && prt->hr() != hr) { + prt = prt->next(); + } + // Loop postcondition is the method postcondition. + return prt; +} + + +#define DRT_CENSUS 0 + +#if DRT_CENSUS +static const int HistoSize = 6; +static int global_histo[HistoSize] = { 0, 0, 0, 0, 0, 0 }; +static int coarsenings = 0; +static int occ_sum = 0; +#endif + +jint OtherRegionsTable::_n_coarsenings = 0; + +PosParPRT* OtherRegionsTable::delete_region_table() { +#if DRT_CENSUS + int histo[HistoSize] = { 0, 0, 0, 0, 0, 0 }; + const int histo_limits[] = { 1, 4, 16, 64, 256, 2048 }; +#endif + + assert(_m.owned_by_self(), "Precondition"); + assert(_n_fine_entries == _max_fine_entries, "Precondition"); + PosParPRT* max = NULL; + jint max_occ = 0; + PosParPRT** max_prev; + size_t max_ind; + +#if SAMPLE_FOR_EVICTION + size_t i = _fine_eviction_start; + for (size_t k = 0; k < _fine_eviction_sample_size; k++) { + size_t ii = i; + // Make sure we get a non-NULL sample. + while (_fine_grain_regions[ii] == NULL) { + ii++; + if (ii == _max_fine_entries) ii = 0; + guarantee(ii != i, "We must find one."); + } + PosParPRT** prev = &_fine_grain_regions[ii]; + PosParPRT* cur = *prev; + while (cur != NULL) { + jint cur_occ = cur->occupied(); + if (max == NULL || cur_occ > max_occ) { + max = cur; + max_prev = prev; + max_ind = i; + max_occ = cur_occ; + } + prev = cur->next_addr(); + cur = cur->next(); + } + i = i + _fine_eviction_stride; + if (i >= _n_fine_entries) i = i - _n_fine_entries; + } + _fine_eviction_start++; + if (_fine_eviction_start >= _n_fine_entries) + _fine_eviction_start -= _n_fine_entries; +#else + for (int i = 0; i < _max_fine_entries; i++) { + PosParPRT** prev = &_fine_grain_regions[i]; + PosParPRT* cur = *prev; + while (cur != NULL) { + jint cur_occ = cur->occupied(); +#if DRT_CENSUS + for (int k = 0; k < HistoSize; k++) { + if (cur_occ <= histo_limits[k]) { + histo[k]++; global_histo[k]++; break; + } + } +#endif + if (max == NULL || cur_occ > max_occ) { + max = cur; + max_prev = prev; + max_ind = i; + max_occ = cur_occ; + } + prev = cur->next_addr(); + cur = cur->next(); + } + } +#endif + // XXX + guarantee(max != NULL, "Since _n_fine_entries > 0"); +#if DRT_CENSUS + gclog_or_tty->print_cr("In a coarsening: histo of occs:"); + for (int k = 0; k < HistoSize; k++) { + gclog_or_tty->print_cr(" <= %4d: %5d.", histo_limits[k], histo[k]); + } + coarsenings++; + occ_sum += max_occ; + if ((coarsenings % 100) == 0) { + gclog_or_tty->print_cr("\ncoarsenings = %d; global summary:", coarsenings); + for (int k = 0; k < HistoSize; k++) { + gclog_or_tty->print_cr(" <= %4d: %5d.", histo_limits[k], global_histo[k]); + } + gclog_or_tty->print_cr("Avg occ of deleted region = %6.2f.", + (float)occ_sum/(float)coarsenings); + } +#endif + + // Set the corresponding coarse bit. + int max_hrs_index = max->hr()->hrs_index(); + if (!_coarse_map.at(max_hrs_index)) { + _coarse_map.at_put(max_hrs_index, true); + _n_coarse_entries++; +#if 0 + gclog_or_tty->print("Coarsened entry in region [" PTR_FORMAT "...] " + "for region [" PTR_FORMAT "...] (%d coarse entries).\n", + hr()->bottom(), + max->hr()->bottom(), + _n_coarse_entries); +#endif + } + + // Unsplice. + *max_prev = max->next(); + Atomic::inc(&_n_coarsenings); + _n_fine_entries--; + return max; +} + + +// At present, this must be called stop-world single-threaded. +void OtherRegionsTable::scrub(CardTableModRefBS* ctbs, + BitMap* region_bm, BitMap* card_bm) { + // First eliminated garbage regions from the coarse map. + if (G1RSScrubVerbose) + gclog_or_tty->print_cr("Scrubbing region %d:", hr()->hrs_index()); + + assert(_coarse_map.size() == region_bm->size(), "Precondition"); + if (G1RSScrubVerbose) + gclog_or_tty->print(" Coarse map: before = %d...", _n_coarse_entries); + _coarse_map.set_intersection(*region_bm); + _n_coarse_entries = _coarse_map.count_one_bits(); + if (G1RSScrubVerbose) + gclog_or_tty->print_cr(" after = %d.", _n_coarse_entries); + + // Now do the fine-grained maps. + for (size_t i = 0; i < _max_fine_entries; i++) { + PosParPRT* cur = _fine_grain_regions[i]; + PosParPRT** prev = &_fine_grain_regions[i]; + while (cur != NULL) { + PosParPRT* nxt = cur->next(); + // If the entire region is dead, eliminate. + if (G1RSScrubVerbose) + gclog_or_tty->print_cr(" For other region %d:", cur->hr()->hrs_index()); + if (!region_bm->at(cur->hr()->hrs_index())) { + *prev = nxt; + cur->set_next(NULL); + _n_fine_entries--; + if (G1RSScrubVerbose) + gclog_or_tty->print_cr(" deleted via region map."); + PosParPRT::free(cur); + } else { + // Do fine-grain elimination. + if (G1RSScrubVerbose) + gclog_or_tty->print(" occ: before = %4d.", cur->occupied()); + cur->scrub(ctbs, card_bm); + if (G1RSScrubVerbose) + gclog_or_tty->print_cr(" after = %4d.", cur->occupied()); + // Did that empty the table completely? + if (cur->occupied() == 0) { + *prev = nxt; + cur->set_next(NULL); + _n_fine_entries--; + PosParPRT::free(cur); + } else { + prev = cur->next_addr(); + } + } + cur = nxt; + } + } + // Since we may have deleted a from_card_cache entry from the RS, clear + // the FCC. + clear_fcc(); +} + + +size_t OtherRegionsTable::occupied() const { + // Cast away const in this case. + MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag); + size_t sum = occ_fine(); + sum += occ_sparse(); + sum += occ_coarse(); + return sum; +} + +size_t OtherRegionsTable::occ_fine() const { + size_t sum = 0; + for (size_t i = 0; i < _max_fine_entries; i++) { + PosParPRT* cur = _fine_grain_regions[i]; + while (cur != NULL) { + sum += cur->occupied(); + cur = cur->next(); + } + } + return sum; +} + +size_t OtherRegionsTable::occ_coarse() const { + return (_n_coarse_entries * PosParPRT::CardsPerRegion); +} + +size_t OtherRegionsTable::occ_sparse() const { + return _sparse_table.occupied(); +} + +size_t OtherRegionsTable::mem_size() const { + // Cast away const in this case. + MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag); + size_t sum = 0; + for (size_t i = 0; i < _max_fine_entries; i++) { + PosParPRT* cur = _fine_grain_regions[i]; + while (cur != NULL) { + sum += cur->mem_size(); + cur = cur->next(); + } + } + sum += (sizeof(PosParPRT*) * _max_fine_entries); + sum += (_coarse_map.size_in_words() * HeapWordSize); + sum += (_sparse_table.mem_size()); + sum += sizeof(*this) - sizeof(_sparse_table); // Avoid double counting above. + return sum; +} + +size_t OtherRegionsTable::static_mem_size() { + return _from_card_cache_mem_size; +} + +size_t OtherRegionsTable::fl_mem_size() { + return PerRegionTable::fl_mem_size() + PosParPRT::fl_mem_size(); +} + +void OtherRegionsTable::clear_fcc() { + for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) { + _from_card_cache[i][hr()->hrs_index()] = -1; + } +} + +void OtherRegionsTable::clear() { + MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag); + for (size_t i = 0; i < _max_fine_entries; i++) { + PosParPRT* cur = _fine_grain_regions[i]; + while (cur != NULL) { + PosParPRT* nxt = cur->next(); + PosParPRT::free(cur); + cur = nxt; + } + _fine_grain_regions[i] = NULL; + } + _sparse_table.clear(); + _coarse_map.clear(); + _n_fine_entries = 0; + _n_coarse_entries = 0; + + clear_fcc(); +} + +void OtherRegionsTable::clear_incoming_entry(HeapRegion* from_hr) { + MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag); + size_t hrs_ind = (size_t)from_hr->hrs_index(); + size_t ind = hrs_ind & _mod_max_fine_entries_mask; + if (del_single_region_table(ind, from_hr)) { + assert(!_coarse_map.at(hrs_ind), "Inv"); + } else { + _coarse_map.par_at_put(hrs_ind, 0); + } + // Check to see if any of the fcc entries come from here. + int hr_ind = hr()->hrs_index(); + for (int tid = 0; tid < HeapRegionRemSet::num_par_rem_sets(); tid++) { + int fcc_ent = _from_card_cache[tid][hr_ind]; + if (fcc_ent != -1) { + HeapWord* card_addr = (HeapWord*) + (uintptr_t(fcc_ent) << CardTableModRefBS::card_shift); + if (hr()->is_in_reserved(card_addr)) { + // Clear the from card cache. + _from_card_cache[tid][hr_ind] = -1; + } + } + } +} + +bool OtherRegionsTable::del_single_region_table(size_t ind, + HeapRegion* hr) { + assert(0 <= ind && ind < _max_fine_entries, "Preconditions."); + PosParPRT** prev_addr = &_fine_grain_regions[ind]; + PosParPRT* prt = *prev_addr; + while (prt != NULL && prt->hr() != hr) { + prev_addr = prt->next_addr(); + prt = prt->next(); + } + if (prt != NULL) { + assert(prt->hr() == hr, "Loop postcondition."); + *prev_addr = prt->next(); + PosParPRT::free(prt); + _n_fine_entries--; + return true; + } else { + return false; + } +} + +bool OtherRegionsTable::contains_reference(oop* from) const { + // Cast away const in this case. + MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag); + return contains_reference_locked(from); +} + +bool OtherRegionsTable::contains_reference_locked(oop* from) const { + HeapRegion* hr = _g1h->heap_region_containing_raw(from); + if (hr == NULL) return false; + size_t hr_ind = hr->hrs_index(); + // Is this region in the coarse map? + if (_coarse_map.at(hr_ind)) return true; + + PosParPRT* prt = find_region_table(hr_ind & _mod_max_fine_entries_mask, + hr); + if (prt != NULL) { + return prt->contains_reference(from); + + } else { + uintptr_t from_card = + (uintptr_t(from) >> CardTableModRefBS::card_shift); + uintptr_t hr_bot_card_index = + uintptr_t(hr->bottom()) >> CardTableModRefBS::card_shift; + assert(from_card >= hr_bot_card_index, "Inv"); + int card_index = from_card - hr_bot_card_index; + return _sparse_table.contains_card((short)hr_ind, card_index); + } + + +} + + +bool HeapRegionRemSet::_par_traversal = false; + +void HeapRegionRemSet::set_par_traversal(bool b) { + assert(_par_traversal != b, "Proper alternation..."); + _par_traversal = b; +} + +int HeapRegionRemSet::num_par_rem_sets() { + // We always have at least two, so that a mutator thread can claim an + // id and add to a rem set. + return (int) MAX2(ParallelGCThreads, (size_t)2); +} + +HeapRegionRemSet::HeapRegionRemSet(G1BlockOffsetSharedArray* bosa, + HeapRegion* hr) + : _bosa(bosa), _other_regions(hr), + _outgoing_region_map(G1CollectedHeap::heap()->max_regions(), + false /* in-resource-area */), + _iter_state(Unclaimed) +{} + + +void HeapRegionRemSet::init_for_par_iteration() { + _iter_state = Unclaimed; +} + +bool HeapRegionRemSet::claim_iter() { + if (_iter_state != Unclaimed) return false; + jint res = Atomic::cmpxchg(Claimed, (jint*)(&_iter_state), Unclaimed); + return (res == Unclaimed); +} + +void HeapRegionRemSet::set_iter_complete() { + _iter_state = Complete; +} + +bool HeapRegionRemSet::iter_is_complete() { + return _iter_state == Complete; +} + + +void HeapRegionRemSet::init_iterator(HeapRegionRemSetIterator* iter) const { + iter->initialize(this); +} + +#ifndef PRODUCT +void HeapRegionRemSet::print() const { + HeapRegionRemSetIterator iter; + init_iterator(&iter); + size_t card_index; + while (iter.has_next(card_index)) { + HeapWord* card_start = + G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index); + gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start); + } + // XXX + if (iter.n_yielded() != occupied()) { + gclog_or_tty->print_cr("Yielded disagrees with occupied:"); + gclog_or_tty->print_cr(" %6d yielded (%6d coarse, %6d fine).", + iter.n_yielded(), + iter.n_yielded_coarse(), iter.n_yielded_fine()); + gclog_or_tty->print_cr(" %6d occ (%6d coarse, %6d fine).", + occupied(), occ_coarse(), occ_fine()); + } + guarantee(iter.n_yielded() == occupied(), + "We should have yielded all the represented cards."); +} +#endif + +void HeapRegionRemSet::cleanup() { + SparsePRT::cleanup_all(); +} + +void HeapRegionRemSet::par_cleanup() { + PosParPRT::par_contract_all(); +} + +void HeapRegionRemSet::add_outgoing_reference(HeapRegion* to_hr) { + _outgoing_region_map.par_at_put(to_hr->hrs_index(), 1); +} + +void HeapRegionRemSet::clear() { + clear_outgoing_entries(); + _outgoing_region_map.clear(); + _other_regions.clear(); + assert(occupied() == 0, "Should be clear."); +} + +void HeapRegionRemSet::clear_outgoing_entries() { + G1CollectedHeap* g1h = G1CollectedHeap::heap(); + size_t i = _outgoing_region_map.get_next_one_offset(0); + while (i < _outgoing_region_map.size()) { + HeapRegion* to_region = g1h->region_at(i); + to_region->rem_set()->clear_incoming_entry(hr()); + i = _outgoing_region_map.get_next_one_offset(i+1); + } +} + + +void HeapRegionRemSet::scrub(CardTableModRefBS* ctbs, + BitMap* region_bm, BitMap* card_bm) { + _other_regions.scrub(ctbs, region_bm, card_bm); +} + +//-------------------- Iteration -------------------- + +HeapRegionRemSetIterator:: +HeapRegionRemSetIterator() : + _hrrs(NULL), + _g1h(G1CollectedHeap::heap()), + _bosa(NULL), + _sparse_iter(size_t(G1CollectedHeap::heap()->reserved_region().start()) + >> CardTableModRefBS::card_shift) +{} + +void HeapRegionRemSetIterator::initialize(const HeapRegionRemSet* hrrs) { + _hrrs = hrrs; + _coarse_map = &_hrrs->_other_regions._coarse_map; + _fine_grain_regions = _hrrs->_other_regions._fine_grain_regions; + _bosa = _hrrs->bosa(); + + _is = Sparse; + // Set these values so that we increment to the first region. + _coarse_cur_region_index = -1; + _coarse_cur_region_cur_card = (PosParPRT::CardsPerRegion-1);; + + _cur_region_cur_card = 0; + + _fine_array_index = -1; + _fine_cur_prt = NULL; + + _n_yielded_coarse = 0; + _n_yielded_fine = 0; + _n_yielded_sparse = 0; + + _sparse_iter.init(&hrrs->_other_regions._sparse_table); +} + +bool HeapRegionRemSetIterator::coarse_has_next(size_t& card_index) { + if (_hrrs->_other_regions._n_coarse_entries == 0) return false; + // Go to the next card. + _coarse_cur_region_cur_card++; + // Was the last the last card in the current region? + if (_coarse_cur_region_cur_card == PosParPRT::CardsPerRegion) { + // Yes: find the next region. This may leave _coarse_cur_region_index + // Set to the last index, in which case there are no more coarse + // regions. + _coarse_cur_region_index = + (int) _coarse_map->get_next_one_offset(_coarse_cur_region_index + 1); + if ((size_t)_coarse_cur_region_index < _coarse_map->size()) { + _coarse_cur_region_cur_card = 0; + HeapWord* r_bot = + _g1h->region_at(_coarse_cur_region_index)->bottom(); + _cur_region_card_offset = _bosa->index_for(r_bot); + } else { + return false; + } + } + // If we didn't return false above, then we can yield a card. + card_index = _cur_region_card_offset + _coarse_cur_region_cur_card; + return true; +} + +void HeapRegionRemSetIterator::fine_find_next_non_null_prt() { + // Otherwise, find the next bucket list in the array. + _fine_array_index++; + while (_fine_array_index < (int) OtherRegionsTable::_max_fine_entries) { + _fine_cur_prt = _fine_grain_regions[_fine_array_index]; + if (_fine_cur_prt != NULL) return; + else _fine_array_index++; + } + assert(_fine_cur_prt == NULL, "Loop post"); +} + +bool HeapRegionRemSetIterator::fine_has_next(size_t& card_index) { + if (fine_has_next()) { + _cur_region_cur_card = + _fine_cur_prt->_bm.get_next_one_offset(_cur_region_cur_card + 1); + } + while (!fine_has_next()) { + if (_cur_region_cur_card == PosParPRT::CardsPerRegion) { + _cur_region_cur_card = 0; + _fine_cur_prt = _fine_cur_prt->next(); + } + if (_fine_cur_prt == NULL) { + fine_find_next_non_null_prt(); + if (_fine_cur_prt == NULL) return false; + } + assert(_fine_cur_prt != NULL && _cur_region_cur_card == 0, + "inv."); + HeapWord* r_bot = + _fine_cur_prt->hr()->bottom(); + _cur_region_card_offset = _bosa->index_for(r_bot); + _cur_region_cur_card = _fine_cur_prt->_bm.get_next_one_offset(0); + } + assert(fine_has_next(), "Or else we exited the loop via the return."); + card_index = _cur_region_card_offset + _cur_region_cur_card; + return true; +} + +bool HeapRegionRemSetIterator::fine_has_next() { + return + _fine_cur_prt != NULL && + _cur_region_cur_card < PosParPRT::CardsPerRegion; +} + +bool HeapRegionRemSetIterator::has_next(size_t& card_index) { + switch (_is) { + case Sparse: + if (_sparse_iter.has_next(card_index)) { + _n_yielded_sparse++; + return true; + } + // Otherwise, deliberate fall-through + _is = Fine; + case Fine: + if (fine_has_next(card_index)) { + _n_yielded_fine++; + return true; + } + // Otherwise, deliberate fall-through + _is = Coarse; + case Coarse: + if (coarse_has_next(card_index)) { + _n_yielded_coarse++; + return true; + } + // Otherwise... + break; + } + assert(ParallelGCThreads > 1 || + n_yielded() == _hrrs->occupied(), + "Should have yielded all the cards in the rem set " + "(in the non-par case)."); + return false; +} + + + +oop** HeapRegionRemSet::_recorded_oops = NULL; +HeapWord** HeapRegionRemSet::_recorded_cards = NULL; +HeapRegion** HeapRegionRemSet::_recorded_regions = NULL; +int HeapRegionRemSet::_n_recorded = 0; + +HeapRegionRemSet::Event* HeapRegionRemSet::_recorded_events = NULL; +int* HeapRegionRemSet::_recorded_event_index = NULL; +int HeapRegionRemSet::_n_recorded_events = 0; + +void HeapRegionRemSet::record(HeapRegion* hr, oop* f) { + if (_recorded_oops == NULL) { + assert(_n_recorded == 0 + && _recorded_cards == NULL + && _recorded_regions == NULL, + "Inv"); + _recorded_oops = NEW_C_HEAP_ARRAY(oop*, MaxRecorded); + _recorded_cards = NEW_C_HEAP_ARRAY(HeapWord*, MaxRecorded); + _recorded_regions = NEW_C_HEAP_ARRAY(HeapRegion*, MaxRecorded); + } + if (_n_recorded == MaxRecorded) { + gclog_or_tty->print_cr("Filled up 'recorded' (%d).", MaxRecorded); + } else { + _recorded_cards[_n_recorded] = + (HeapWord*)align_size_down(uintptr_t(f), + CardTableModRefBS::card_size); + _recorded_oops[_n_recorded] = f; + _recorded_regions[_n_recorded] = hr; + _n_recorded++; + } +} + +void HeapRegionRemSet::record_event(Event evnt) { + if (!G1RecordHRRSEvents) return; + + if (_recorded_events == NULL) { + assert(_n_recorded_events == 0 + && _recorded_event_index == NULL, + "Inv"); + _recorded_events = NEW_C_HEAP_ARRAY(Event, MaxRecordedEvents); + _recorded_event_index = NEW_C_HEAP_ARRAY(int, MaxRecordedEvents); + } + if (_n_recorded_events == MaxRecordedEvents) { + gclog_or_tty->print_cr("Filled up 'recorded_events' (%d).", MaxRecordedEvents); + } else { + _recorded_events[_n_recorded_events] = evnt; + _recorded_event_index[_n_recorded_events] = _n_recorded; + _n_recorded_events++; + } +} + +void HeapRegionRemSet::print_event(outputStream* str, Event evnt) { + switch (evnt) { + case Event_EvacStart: + str->print("Evac Start"); + break; + case Event_EvacEnd: + str->print("Evac End"); + break; + case Event_RSUpdateEnd: + str->print("RS Update End"); + break; + } +} + +void HeapRegionRemSet::print_recorded() { + int cur_evnt = 0; + Event cur_evnt_kind; + int cur_evnt_ind = 0; + if (_n_recorded_events > 0) { + cur_evnt_kind = _recorded_events[cur_evnt]; + cur_evnt_ind = _recorded_event_index[cur_evnt]; + } + + for (int i = 0; i < _n_recorded; i++) { + while (cur_evnt < _n_recorded_events && i == cur_evnt_ind) { + gclog_or_tty->print("Event: "); + print_event(gclog_or_tty, cur_evnt_kind); + gclog_or_tty->print_cr(""); + cur_evnt++; + if (cur_evnt < MaxRecordedEvents) { + cur_evnt_kind = _recorded_events[cur_evnt]; + cur_evnt_ind = _recorded_event_index[cur_evnt]; + } + } + gclog_or_tty->print("Added card " PTR_FORMAT " to region [" PTR_FORMAT "...]" + " for ref " PTR_FORMAT ".\n", + _recorded_cards[i], _recorded_regions[i]->bottom(), + _recorded_oops[i]); + } +} + +#ifndef PRODUCT +void HeapRegionRemSet::test() { + os::sleep(Thread::current(), (jlong)5000, false); + G1CollectedHeap* g1h = G1CollectedHeap::heap(); + + // Run with "-XX:G1LogRSRegionEntries=2", so that 1 and 5 end up in same + // hash bucket. + HeapRegion* hr0 = g1h->region_at(0); + HeapRegion* hr1 = g1h->region_at(1); + HeapRegion* hr2 = g1h->region_at(5); + HeapRegion* hr3 = g1h->region_at(6); + HeapRegion* hr4 = g1h->region_at(7); + HeapRegion* hr5 = g1h->region_at(8); + + HeapWord* hr1_start = hr1->bottom(); + HeapWord* hr1_mid = hr1_start + HeapRegion::GrainWords/2; + HeapWord* hr1_last = hr1->end() - 1; + + HeapWord* hr2_start = hr2->bottom(); + HeapWord* hr2_mid = hr2_start + HeapRegion::GrainWords/2; + HeapWord* hr2_last = hr2->end() - 1; + + HeapWord* hr3_start = hr3->bottom(); + HeapWord* hr3_mid = hr3_start + HeapRegion::GrainWords/2; + HeapWord* hr3_last = hr3->end() - 1; + + HeapRegionRemSet* hrrs = hr0->rem_set(); + + // Make three references from region 0x101... + hrrs->add_reference((oop*)hr1_start); + hrrs->add_reference((oop*)hr1_mid); + hrrs->add_reference((oop*)hr1_last); + + hrrs->add_reference((oop*)hr2_start); + hrrs->add_reference((oop*)hr2_mid); + hrrs->add_reference((oop*)hr2_last); + + hrrs->add_reference((oop*)hr3_start); + hrrs->add_reference((oop*)hr3_mid); + hrrs->add_reference((oop*)hr3_last); + + // Now cause a coarsening. + hrrs->add_reference((oop*)hr4->bottom()); + hrrs->add_reference((oop*)hr5->bottom()); + + // Now, does iteration yield these three? + HeapRegionRemSetIterator iter; + hrrs->init_iterator(&iter); + size_t sum = 0; + size_t card_index; + while (iter.has_next(card_index)) { + HeapWord* card_start = + G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index); + gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start); + sum++; + } + guarantee(sum == 11 - 3 + 2048, "Failure"); + guarantee(sum == hrrs->occupied(), "Failure"); +} +#endif