Fri, 18 Feb 2011 10:07:34 -0800
7020042: G1: Partially remove fix for 6994628
Summary: Disable reference discovery and processing during concurrent marking by disabling fix for 6994628.
Reviewed-by: tonyp, ysr
ysr@777 | 1 | /* |
johnc@2504 | 2 | * Copyright (c) 2001, 2011, Oracle and/or its affiliates. All rights reserved. |
ysr@777 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
ysr@777 | 4 | * |
ysr@777 | 5 | * This code is free software; you can redistribute it and/or modify it |
ysr@777 | 6 | * under the terms of the GNU General Public License version 2 only, as |
ysr@777 | 7 | * published by the Free Software Foundation. |
ysr@777 | 8 | * |
ysr@777 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
ysr@777 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
ysr@777 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
ysr@777 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
ysr@777 | 13 | * accompanied this code). |
ysr@777 | 14 | * |
ysr@777 | 15 | * You should have received a copy of the GNU General Public License version |
ysr@777 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
ysr@777 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
ysr@777 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
ysr@777 | 22 | * |
ysr@777 | 23 | */ |
ysr@777 | 24 | |
stefank@2314 | 25 | #include "precompiled.hpp" |
stefank@2314 | 26 | #include "gc_implementation/g1/bufferingOopClosure.hpp" |
stefank@2314 | 27 | #include "gc_implementation/g1/concurrentG1Refine.hpp" |
stefank@2314 | 28 | #include "gc_implementation/g1/concurrentG1RefineThread.hpp" |
stefank@2314 | 29 | #include "gc_implementation/g1/g1BlockOffsetTable.inline.hpp" |
stefank@2314 | 30 | #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" |
stefank@2314 | 31 | #include "gc_implementation/g1/g1CollectorPolicy.hpp" |
stefank@2314 | 32 | #include "gc_implementation/g1/g1OopClosures.inline.hpp" |
stefank@2314 | 33 | #include "gc_implementation/g1/g1RemSet.inline.hpp" |
stefank@2314 | 34 | #include "gc_implementation/g1/heapRegionSeq.inline.hpp" |
stefank@2314 | 35 | #include "memory/iterator.hpp" |
stefank@2314 | 36 | #include "oops/oop.inline.hpp" |
stefank@2314 | 37 | #include "utilities/intHisto.hpp" |
ysr@777 | 38 | |
ysr@777 | 39 | #define CARD_REPEAT_HISTO 0 |
ysr@777 | 40 | |
ysr@777 | 41 | #if CARD_REPEAT_HISTO |
ysr@777 | 42 | static size_t ct_freq_sz; |
ysr@777 | 43 | static jbyte* ct_freq = NULL; |
ysr@777 | 44 | |
ysr@777 | 45 | void init_ct_freq_table(size_t heap_sz_bytes) { |
ysr@777 | 46 | if (ct_freq == NULL) { |
ysr@777 | 47 | ct_freq_sz = heap_sz_bytes/CardTableModRefBS::card_size; |
ysr@777 | 48 | ct_freq = new jbyte[ct_freq_sz]; |
ysr@777 | 49 | for (size_t j = 0; j < ct_freq_sz; j++) ct_freq[j] = 0; |
ysr@777 | 50 | } |
ysr@777 | 51 | } |
ysr@777 | 52 | |
ysr@777 | 53 | void ct_freq_note_card(size_t index) { |
ysr@777 | 54 | assert(0 <= index && index < ct_freq_sz, "Bounds error."); |
ysr@777 | 55 | if (ct_freq[index] < 100) { ct_freq[index]++; } |
ysr@777 | 56 | } |
ysr@777 | 57 | |
ysr@777 | 58 | static IntHistogram card_repeat_count(10, 10); |
ysr@777 | 59 | |
ysr@777 | 60 | void ct_freq_update_histo_and_reset() { |
ysr@777 | 61 | for (size_t j = 0; j < ct_freq_sz; j++) { |
ysr@777 | 62 | card_repeat_count.add_entry(ct_freq[j]); |
ysr@777 | 63 | ct_freq[j] = 0; |
ysr@777 | 64 | } |
ysr@777 | 65 | |
ysr@777 | 66 | } |
ysr@777 | 67 | #endif |
ysr@777 | 68 | |
ysr@777 | 69 | |
ysr@777 | 70 | class IntoCSOopClosure: public OopsInHeapRegionClosure { |
ysr@777 | 71 | OopsInHeapRegionClosure* _blk; |
ysr@777 | 72 | G1CollectedHeap* _g1; |
ysr@777 | 73 | public: |
ysr@777 | 74 | IntoCSOopClosure(G1CollectedHeap* g1, OopsInHeapRegionClosure* blk) : |
ysr@777 | 75 | _g1(g1), _blk(blk) {} |
ysr@777 | 76 | void set_region(HeapRegion* from) { |
ysr@777 | 77 | _blk->set_region(from); |
ysr@777 | 78 | } |
ysr@1280 | 79 | virtual void do_oop(narrowOop* p) { do_oop_work(p); } |
ysr@1280 | 80 | virtual void do_oop( oop* p) { do_oop_work(p); } |
ysr@1280 | 81 | template <class T> void do_oop_work(T* p) { |
ysr@1280 | 82 | oop obj = oopDesc::load_decode_heap_oop(p); |
ysr@777 | 83 | if (_g1->obj_in_cs(obj)) _blk->do_oop(p); |
ysr@777 | 84 | } |
ysr@777 | 85 | bool apply_to_weak_ref_discovered_field() { return true; } |
ysr@777 | 86 | bool idempotent() { return true; } |
ysr@777 | 87 | }; |
ysr@777 | 88 | |
ysr@777 | 89 | class VerifyRSCleanCardOopClosure: public OopClosure { |
ysr@777 | 90 | G1CollectedHeap* _g1; |
ysr@777 | 91 | public: |
ysr@777 | 92 | VerifyRSCleanCardOopClosure(G1CollectedHeap* g1) : _g1(g1) {} |
ysr@777 | 93 | |
ysr@1280 | 94 | virtual void do_oop(narrowOop* p) { do_oop_work(p); } |
ysr@1280 | 95 | virtual void do_oop( oop* p) { do_oop_work(p); } |
ysr@1280 | 96 | template <class T> void do_oop_work(T* p) { |
ysr@1280 | 97 | oop obj = oopDesc::load_decode_heap_oop(p); |
ysr@777 | 98 | HeapRegion* to = _g1->heap_region_containing(obj); |
ysr@777 | 99 | guarantee(to == NULL || !to->in_collection_set(), |
ysr@777 | 100 | "Missed a rem set member."); |
ysr@777 | 101 | } |
ysr@777 | 102 | }; |
ysr@777 | 103 | |
johnc@2216 | 104 | G1RemSet::G1RemSet(G1CollectedHeap* g1, CardTableModRefBS* ct_bs) |
johnc@2216 | 105 | : _g1(g1), _conc_refine_cards(0), |
johnc@2216 | 106 | _ct_bs(ct_bs), _g1p(_g1->g1_policy()), |
ysr@777 | 107 | _cg1r(g1->concurrent_g1_refine()), |
johnc@2060 | 108 | _cset_rs_update_cl(NULL), |
ysr@777 | 109 | _cards_scanned(NULL), _total_cards_scanned(0) |
ysr@777 | 110 | { |
ysr@777 | 111 | _seq_task = new SubTasksDone(NumSeqTasks); |
iveresov@1051 | 112 | guarantee(n_workers() > 0, "There should be some workers"); |
johnc@2060 | 113 | _cset_rs_update_cl = NEW_C_HEAP_ARRAY(OopsInHeapRegionClosure*, n_workers()); |
iveresov@1051 | 114 | for (uint i = 0; i < n_workers(); i++) { |
johnc@2060 | 115 | _cset_rs_update_cl[i] = NULL; |
iveresov@1051 | 116 | } |
ysr@777 | 117 | } |
ysr@777 | 118 | |
johnc@2216 | 119 | G1RemSet::~G1RemSet() { |
ysr@777 | 120 | delete _seq_task; |
iveresov@1051 | 121 | for (uint i = 0; i < n_workers(); i++) { |
johnc@2060 | 122 | assert(_cset_rs_update_cl[i] == NULL, "it should be"); |
iveresov@1051 | 123 | } |
johnc@2060 | 124 | FREE_C_HEAP_ARRAY(OopsInHeapRegionClosure*, _cset_rs_update_cl); |
ysr@777 | 125 | } |
ysr@777 | 126 | |
ysr@777 | 127 | void CountNonCleanMemRegionClosure::do_MemRegion(MemRegion mr) { |
ysr@777 | 128 | if (_g1->is_in_g1_reserved(mr.start())) { |
ysr@777 | 129 | _n += (int) ((mr.byte_size() / CardTableModRefBS::card_size)); |
ysr@777 | 130 | if (_start_first == NULL) _start_first = mr.start(); |
ysr@777 | 131 | } |
ysr@777 | 132 | } |
ysr@777 | 133 | |
ysr@777 | 134 | class ScanRSClosure : public HeapRegionClosure { |
ysr@777 | 135 | size_t _cards_done, _cards; |
ysr@777 | 136 | G1CollectedHeap* _g1h; |
ysr@777 | 137 | OopsInHeapRegionClosure* _oc; |
ysr@777 | 138 | G1BlockOffsetSharedArray* _bot_shared; |
ysr@777 | 139 | CardTableModRefBS *_ct_bs; |
ysr@777 | 140 | int _worker_i; |
iveresov@1696 | 141 | int _block_size; |
ysr@777 | 142 | bool _try_claimed; |
ysr@777 | 143 | public: |
ysr@777 | 144 | ScanRSClosure(OopsInHeapRegionClosure* oc, int worker_i) : |
ysr@777 | 145 | _oc(oc), |
ysr@777 | 146 | _cards(0), |
ysr@777 | 147 | _cards_done(0), |
ysr@777 | 148 | _worker_i(worker_i), |
ysr@777 | 149 | _try_claimed(false) |
ysr@777 | 150 | { |
ysr@777 | 151 | _g1h = G1CollectedHeap::heap(); |
ysr@777 | 152 | _bot_shared = _g1h->bot_shared(); |
ysr@777 | 153 | _ct_bs = (CardTableModRefBS*) (_g1h->barrier_set()); |
iveresov@1696 | 154 | _block_size = MAX2<int>(G1RSetScanBlockSize, 1); |
ysr@777 | 155 | } |
ysr@777 | 156 | |
ysr@777 | 157 | void set_try_claimed() { _try_claimed = true; } |
ysr@777 | 158 | |
ysr@777 | 159 | void scanCard(size_t index, HeapRegion *r) { |
ysr@777 | 160 | _cards_done++; |
ysr@777 | 161 | DirtyCardToOopClosure* cl = |
ysr@777 | 162 | r->new_dcto_closure(_oc, |
ysr@777 | 163 | CardTableModRefBS::Precise, |
ysr@777 | 164 | HeapRegionDCTOC::IntoCSFilterKind); |
ysr@777 | 165 | |
ysr@777 | 166 | // Set the "from" region in the closure. |
ysr@777 | 167 | _oc->set_region(r); |
ysr@777 | 168 | HeapWord* card_start = _bot_shared->address_for_index(index); |
ysr@777 | 169 | HeapWord* card_end = card_start + G1BlockOffsetSharedArray::N_words; |
ysr@777 | 170 | Space *sp = SharedHeap::heap()->space_containing(card_start); |
ysr@777 | 171 | MemRegion sm_region; |
ysr@777 | 172 | if (ParallelGCThreads > 0) { |
ysr@777 | 173 | // first find the used area |
ysr@777 | 174 | sm_region = sp->used_region_at_save_marks(); |
ysr@777 | 175 | } else { |
ysr@777 | 176 | // The closure is not idempotent. We shouldn't look at objects |
ysr@777 | 177 | // allocated during the GC. |
ysr@777 | 178 | sm_region = sp->used_region_at_save_marks(); |
ysr@777 | 179 | } |
ysr@777 | 180 | MemRegion mr = sm_region.intersection(MemRegion(card_start,card_end)); |
ysr@777 | 181 | if (!mr.is_empty()) { |
ysr@777 | 182 | cl->do_MemRegion(mr); |
ysr@777 | 183 | } |
ysr@777 | 184 | } |
ysr@777 | 185 | |
ysr@777 | 186 | void printCard(HeapRegion* card_region, size_t card_index, |
ysr@777 | 187 | HeapWord* card_start) { |
ysr@777 | 188 | gclog_or_tty->print_cr("T %d Region [" PTR_FORMAT ", " PTR_FORMAT ") " |
ysr@777 | 189 | "RS names card %p: " |
ysr@777 | 190 | "[" PTR_FORMAT ", " PTR_FORMAT ")", |
ysr@777 | 191 | _worker_i, |
ysr@777 | 192 | card_region->bottom(), card_region->end(), |
ysr@777 | 193 | card_index, |
ysr@777 | 194 | card_start, card_start + G1BlockOffsetSharedArray::N_words); |
ysr@777 | 195 | } |
ysr@777 | 196 | |
ysr@777 | 197 | bool doHeapRegion(HeapRegion* r) { |
ysr@777 | 198 | assert(r->in_collection_set(), "should only be called on elements of CS."); |
ysr@777 | 199 | HeapRegionRemSet* hrrs = r->rem_set(); |
ysr@777 | 200 | if (hrrs->iter_is_complete()) return false; // All done. |
ysr@777 | 201 | if (!_try_claimed && !hrrs->claim_iter()) return false; |
apetrusenko@1231 | 202 | _g1h->push_dirty_cards_region(r); |
ysr@777 | 203 | // If we didn't return above, then |
ysr@777 | 204 | // _try_claimed || r->claim_iter() |
ysr@777 | 205 | // is true: either we're supposed to work on claimed-but-not-complete |
ysr@777 | 206 | // regions, or we successfully claimed the region. |
ysr@777 | 207 | HeapRegionRemSetIterator* iter = _g1h->rem_set_iterator(_worker_i); |
ysr@777 | 208 | hrrs->init_iterator(iter); |
ysr@777 | 209 | size_t card_index; |
iveresov@1696 | 210 | |
iveresov@1696 | 211 | // We claim cards in block so as to recude the contention. The block size is determined by |
iveresov@1696 | 212 | // the G1RSetScanBlockSize parameter. |
iveresov@1696 | 213 | size_t jump_to_card = hrrs->iter_claimed_next(_block_size); |
iveresov@1696 | 214 | for (size_t current_card = 0; iter->has_next(card_index); current_card++) { |
iveresov@1696 | 215 | if (current_card >= jump_to_card + _block_size) { |
iveresov@1696 | 216 | jump_to_card = hrrs->iter_claimed_next(_block_size); |
iveresov@1182 | 217 | } |
iveresov@1696 | 218 | if (current_card < jump_to_card) continue; |
ysr@777 | 219 | HeapWord* card_start = _g1h->bot_shared()->address_for_index(card_index); |
ysr@777 | 220 | #if 0 |
ysr@777 | 221 | gclog_or_tty->print("Rem set iteration yielded card [" PTR_FORMAT ", " PTR_FORMAT ").\n", |
ysr@777 | 222 | card_start, card_start + CardTableModRefBS::card_size_in_words); |
ysr@777 | 223 | #endif |
ysr@777 | 224 | |
ysr@777 | 225 | HeapRegion* card_region = _g1h->heap_region_containing(card_start); |
ysr@777 | 226 | assert(card_region != NULL, "Yielding cards not in the heap?"); |
ysr@777 | 227 | _cards++; |
ysr@777 | 228 | |
apetrusenko@1231 | 229 | if (!card_region->is_on_dirty_cards_region_list()) { |
apetrusenko@1231 | 230 | _g1h->push_dirty_cards_region(card_region); |
apetrusenko@1231 | 231 | } |
apetrusenko@1231 | 232 | |
iveresov@1182 | 233 | // If the card is dirty, then we will scan it during updateRS. |
iveresov@1182 | 234 | if (!card_region->in_collection_set() && !_ct_bs->is_card_dirty(card_index)) { |
iveresov@1696 | 235 | // We make the card as "claimed" lazily (so races are possible but they're benign), |
iveresov@1696 | 236 | // which reduces the number of duplicate scans (the rsets of the regions in the cset |
iveresov@1696 | 237 | // can intersect). |
iveresov@1696 | 238 | if (!_ct_bs->is_card_claimed(card_index)) { |
iveresov@1696 | 239 | _ct_bs->set_card_claimed(card_index); |
iveresov@1696 | 240 | scanCard(card_index, card_region); |
iveresov@1696 | 241 | } |
ysr@777 | 242 | } |
ysr@777 | 243 | } |
iveresov@1182 | 244 | if (!_try_claimed) { |
iveresov@1182 | 245 | hrrs->set_iter_complete(); |
iveresov@1182 | 246 | } |
ysr@777 | 247 | return false; |
ysr@777 | 248 | } |
ysr@777 | 249 | // Set all cards back to clean. |
ysr@777 | 250 | void cleanup() {_g1h->cleanUpCardTable();} |
ysr@777 | 251 | size_t cards_done() { return _cards_done;} |
ysr@777 | 252 | size_t cards_looked_up() { return _cards;} |
ysr@777 | 253 | }; |
ysr@777 | 254 | |
ysr@777 | 255 | // We want the parallel threads to start their scanning at |
ysr@777 | 256 | // different collection set regions to avoid contention. |
ysr@777 | 257 | // If we have: |
ysr@777 | 258 | // n collection set regions |
ysr@777 | 259 | // p threads |
ysr@777 | 260 | // Then thread t will start at region t * floor (n/p) |
ysr@777 | 261 | |
johnc@2216 | 262 | HeapRegion* G1RemSet::calculateStartRegion(int worker_i) { |
ysr@777 | 263 | HeapRegion* result = _g1p->collection_set(); |
ysr@777 | 264 | if (ParallelGCThreads > 0) { |
ysr@777 | 265 | size_t cs_size = _g1p->collection_set_size(); |
ysr@777 | 266 | int n_workers = _g1->workers()->total_workers(); |
ysr@777 | 267 | size_t cs_spans = cs_size / n_workers; |
ysr@777 | 268 | size_t ind = cs_spans * worker_i; |
ysr@777 | 269 | for (size_t i = 0; i < ind; i++) |
ysr@777 | 270 | result = result->next_in_collection_set(); |
ysr@777 | 271 | } |
ysr@777 | 272 | return result; |
ysr@777 | 273 | } |
ysr@777 | 274 | |
johnc@2216 | 275 | void G1RemSet::scanRS(OopsInHeapRegionClosure* oc, int worker_i) { |
ysr@777 | 276 | double rs_time_start = os::elapsedTime(); |
ysr@777 | 277 | HeapRegion *startRegion = calculateStartRegion(worker_i); |
ysr@777 | 278 | |
iveresov@1696 | 279 | ScanRSClosure scanRScl(oc, worker_i); |
ysr@777 | 280 | _g1->collection_set_iterate_from(startRegion, &scanRScl); |
ysr@777 | 281 | scanRScl.set_try_claimed(); |
ysr@777 | 282 | _g1->collection_set_iterate_from(startRegion, &scanRScl); |
ysr@777 | 283 | |
iveresov@1696 | 284 | double scan_rs_time_sec = os::elapsedTime() - rs_time_start; |
ysr@777 | 285 | |
ysr@777 | 286 | assert( _cards_scanned != NULL, "invariant" ); |
ysr@777 | 287 | _cards_scanned[worker_i] = scanRScl.cards_done(); |
ysr@777 | 288 | |
ysr@777 | 289 | _g1p->record_scan_rs_time(worker_i, scan_rs_time_sec * 1000.0); |
ysr@777 | 290 | } |
ysr@777 | 291 | |
johnc@2060 | 292 | // Closure used for updating RSets and recording references that |
johnc@2060 | 293 | // point into the collection set. Only called during an |
johnc@2060 | 294 | // evacuation pause. |
ysr@777 | 295 | |
johnc@2060 | 296 | class RefineRecordRefsIntoCSCardTableEntryClosure: public CardTableEntryClosure { |
johnc@2060 | 297 | G1RemSet* _g1rs; |
johnc@2060 | 298 | DirtyCardQueue* _into_cset_dcq; |
johnc@2060 | 299 | public: |
johnc@2060 | 300 | RefineRecordRefsIntoCSCardTableEntryClosure(G1CollectedHeap* g1h, |
johnc@2060 | 301 | DirtyCardQueue* into_cset_dcq) : |
johnc@2060 | 302 | _g1rs(g1h->g1_rem_set()), _into_cset_dcq(into_cset_dcq) |
johnc@2060 | 303 | {} |
johnc@2060 | 304 | bool do_card_ptr(jbyte* card_ptr, int worker_i) { |
johnc@2060 | 305 | // The only time we care about recording cards that |
johnc@2060 | 306 | // contain references that point into the collection set |
johnc@2060 | 307 | // is during RSet updating within an evacuation pause. |
johnc@2060 | 308 | // In this case worker_i should be the id of a GC worker thread. |
johnc@2060 | 309 | assert(SafepointSynchronize::is_at_safepoint(), "not during an evacuation pause"); |
brutisso@2646 | 310 | assert(worker_i < (int) (ParallelGCThreads == 0 ? 1 : ParallelGCThreads), "should be a GC worker"); |
johnc@2060 | 311 | |
johnc@2060 | 312 | if (_g1rs->concurrentRefineOneCard(card_ptr, worker_i, true)) { |
johnc@2060 | 313 | // 'card_ptr' contains references that point into the collection |
johnc@2060 | 314 | // set. We need to record the card in the DCQS |
johnc@2060 | 315 | // (G1CollectedHeap::into_cset_dirty_card_queue_set()) |
johnc@2060 | 316 | // that's used for that purpose. |
johnc@2060 | 317 | // |
johnc@2060 | 318 | // Enqueue the card |
johnc@2060 | 319 | _into_cset_dcq->enqueue(card_ptr); |
johnc@2060 | 320 | } |
johnc@2060 | 321 | return true; |
johnc@2060 | 322 | } |
johnc@2060 | 323 | }; |
johnc@2060 | 324 | |
johnc@2216 | 325 | void G1RemSet::updateRS(DirtyCardQueue* into_cset_dcq, int worker_i) { |
ysr@777 | 326 | double start = os::elapsedTime(); |
johnc@2060 | 327 | // Apply the given closure to all remaining log entries. |
johnc@2060 | 328 | RefineRecordRefsIntoCSCardTableEntryClosure into_cset_update_rs_cl(_g1, into_cset_dcq); |
johnc@2060 | 329 | _g1->iterate_dirty_card_closure(&into_cset_update_rs_cl, into_cset_dcq, false, worker_i); |
johnc@2060 | 330 | |
iveresov@1229 | 331 | // Now there should be no dirty cards. |
iveresov@1229 | 332 | if (G1RSLogCheckCardTable) { |
iveresov@1229 | 333 | CountNonCleanMemRegionClosure cl(_g1); |
iveresov@1229 | 334 | _ct_bs->mod_card_iterate(&cl); |
iveresov@1229 | 335 | // XXX This isn't true any more: keeping cards of young regions |
iveresov@1229 | 336 | // marked dirty broke it. Need some reasonable fix. |
iveresov@1229 | 337 | guarantee(cl.n() == 0, "Card table should be clean."); |
ysr@777 | 338 | } |
iveresov@1229 | 339 | |
ysr@777 | 340 | _g1p->record_update_rs_time(worker_i, (os::elapsedTime() - start) * 1000.0); |
ysr@777 | 341 | } |
ysr@777 | 342 | |
ysr@777 | 343 | #ifndef PRODUCT |
ysr@777 | 344 | class PrintRSClosure : public HeapRegionClosure { |
ysr@777 | 345 | int _count; |
ysr@777 | 346 | public: |
ysr@777 | 347 | PrintRSClosure() : _count(0) {} |
ysr@777 | 348 | bool doHeapRegion(HeapRegion* r) { |
ysr@777 | 349 | HeapRegionRemSet* hrrs = r->rem_set(); |
ysr@777 | 350 | _count += (int) hrrs->occupied(); |
ysr@777 | 351 | if (hrrs->occupied() == 0) { |
ysr@777 | 352 | gclog_or_tty->print("Heap Region [" PTR_FORMAT ", " PTR_FORMAT ") " |
ysr@777 | 353 | "has no remset entries\n", |
ysr@777 | 354 | r->bottom(), r->end()); |
ysr@777 | 355 | } else { |
ysr@777 | 356 | gclog_or_tty->print("Printing rem set for heap region [" PTR_FORMAT ", " PTR_FORMAT ")\n", |
ysr@777 | 357 | r->bottom(), r->end()); |
ysr@777 | 358 | r->print(); |
ysr@777 | 359 | hrrs->print(); |
ysr@777 | 360 | gclog_or_tty->print("\nDone printing rem set\n"); |
ysr@777 | 361 | } |
ysr@777 | 362 | return false; |
ysr@777 | 363 | } |
ysr@777 | 364 | int occupied() {return _count;} |
ysr@777 | 365 | }; |
ysr@777 | 366 | #endif |
ysr@777 | 367 | |
ysr@777 | 368 | class CountRSSizeClosure: public HeapRegionClosure { |
ysr@777 | 369 | size_t _n; |
ysr@777 | 370 | size_t _tot; |
ysr@777 | 371 | size_t _max; |
ysr@777 | 372 | HeapRegion* _max_r; |
ysr@777 | 373 | enum { |
ysr@777 | 374 | N = 20, |
ysr@777 | 375 | MIN = 6 |
ysr@777 | 376 | }; |
ysr@777 | 377 | int _histo[N]; |
ysr@777 | 378 | public: |
ysr@777 | 379 | CountRSSizeClosure() : _n(0), _tot(0), _max(0), _max_r(NULL) { |
ysr@777 | 380 | for (int i = 0; i < N; i++) _histo[i] = 0; |
ysr@777 | 381 | } |
ysr@777 | 382 | bool doHeapRegion(HeapRegion* r) { |
ysr@777 | 383 | if (!r->continuesHumongous()) { |
ysr@777 | 384 | size_t occ = r->rem_set()->occupied(); |
ysr@777 | 385 | _n++; |
ysr@777 | 386 | _tot += occ; |
ysr@777 | 387 | if (occ > _max) { |
ysr@777 | 388 | _max = occ; |
ysr@777 | 389 | _max_r = r; |
ysr@777 | 390 | } |
ysr@777 | 391 | // Fit it into a histo bin. |
ysr@777 | 392 | int s = 1 << MIN; |
ysr@777 | 393 | int i = 0; |
ysr@777 | 394 | while (occ > (size_t) s && i < (N-1)) { |
ysr@777 | 395 | s = s << 1; |
ysr@777 | 396 | i++; |
ysr@777 | 397 | } |
ysr@777 | 398 | _histo[i]++; |
ysr@777 | 399 | } |
ysr@777 | 400 | return false; |
ysr@777 | 401 | } |
ysr@777 | 402 | size_t n() { return _n; } |
ysr@777 | 403 | size_t tot() { return _tot; } |
ysr@777 | 404 | size_t mx() { return _max; } |
ysr@777 | 405 | HeapRegion* mxr() { return _max_r; } |
ysr@777 | 406 | void print_histo() { |
ysr@777 | 407 | int mx = N; |
ysr@777 | 408 | while (mx >= 0) { |
ysr@777 | 409 | if (_histo[mx-1] > 0) break; |
ysr@777 | 410 | mx--; |
ysr@777 | 411 | } |
ysr@777 | 412 | gclog_or_tty->print_cr("Number of regions with given RS sizes:"); |
ysr@777 | 413 | gclog_or_tty->print_cr(" <= %8d %8d", 1 << MIN, _histo[0]); |
ysr@777 | 414 | for (int i = 1; i < mx-1; i++) { |
ysr@777 | 415 | gclog_or_tty->print_cr(" %8d - %8d %8d", |
ysr@777 | 416 | (1 << (MIN + i - 1)) + 1, |
ysr@777 | 417 | 1 << (MIN + i), |
ysr@777 | 418 | _histo[i]); |
ysr@777 | 419 | } |
ysr@777 | 420 | gclog_or_tty->print_cr(" > %8d %8d", (1 << (MIN+mx-2))+1, _histo[mx-1]); |
ysr@777 | 421 | } |
ysr@777 | 422 | }; |
ysr@777 | 423 | |
johnc@2216 | 424 | void G1RemSet::cleanupHRRS() { |
ysr@777 | 425 | HeapRegionRemSet::cleanup(); |
ysr@777 | 426 | } |
ysr@777 | 427 | |
johnc@2216 | 428 | void G1RemSet::oops_into_collection_set_do(OopsInHeapRegionClosure* oc, |
ysr@777 | 429 | int worker_i) { |
ysr@777 | 430 | #if CARD_REPEAT_HISTO |
ysr@777 | 431 | ct_freq_update_histo_and_reset(); |
ysr@777 | 432 | #endif |
ysr@777 | 433 | if (worker_i == 0) { |
ysr@777 | 434 | _cg1r->clear_and_record_card_counts(); |
ysr@777 | 435 | } |
ysr@777 | 436 | |
ysr@777 | 437 | // Make this into a command-line flag... |
ysr@777 | 438 | if (G1RSCountHisto && (ParallelGCThreads == 0 || worker_i == 0)) { |
ysr@777 | 439 | CountRSSizeClosure count_cl; |
ysr@777 | 440 | _g1->heap_region_iterate(&count_cl); |
ysr@777 | 441 | gclog_or_tty->print_cr("Avg of %d RS counts is %f, max is %d, " |
ysr@777 | 442 | "max region is " PTR_FORMAT, |
ysr@777 | 443 | count_cl.n(), (float)count_cl.tot()/(float)count_cl.n(), |
ysr@777 | 444 | count_cl.mx(), count_cl.mxr()); |
ysr@777 | 445 | count_cl.print_histo(); |
ysr@777 | 446 | } |
ysr@777 | 447 | |
johnc@2060 | 448 | // We cache the value of 'oc' closure into the appropriate slot in the |
johnc@2060 | 449 | // _cset_rs_update_cl for this worker |
johnc@2060 | 450 | assert(worker_i < (int)n_workers(), "sanity"); |
johnc@2060 | 451 | _cset_rs_update_cl[worker_i] = oc; |
johnc@2060 | 452 | |
johnc@2060 | 453 | // A DirtyCardQueue that is used to hold cards containing references |
johnc@2060 | 454 | // that point into the collection set. This DCQ is associated with a |
johnc@2060 | 455 | // special DirtyCardQueueSet (see g1CollectedHeap.hpp). Under normal |
johnc@2060 | 456 | // circumstances (i.e. the pause successfully completes), these cards |
johnc@2060 | 457 | // are just discarded (there's no need to update the RSets of regions |
johnc@2060 | 458 | // that were in the collection set - after the pause these regions |
johnc@2060 | 459 | // are wholly 'free' of live objects. In the event of an evacuation |
johnc@2060 | 460 | // failure the cards/buffers in this queue set are: |
johnc@2060 | 461 | // * passed to the DirtyCardQueueSet that is used to manage deferred |
johnc@2060 | 462 | // RSet updates, or |
johnc@2060 | 463 | // * scanned for references that point into the collection set |
johnc@2060 | 464 | // and the RSet of the corresponding region in the collection set |
johnc@2060 | 465 | // is updated immediately. |
johnc@2060 | 466 | DirtyCardQueue into_cset_dcq(&_g1->into_cset_dirty_card_queue_set()); |
johnc@2060 | 467 | |
johnc@2063 | 468 | assert((ParallelGCThreads > 0) || worker_i == 0, "invariant"); |
johnc@2063 | 469 | |
johnc@2063 | 470 | // The two flags below were introduced temporarily to serialize |
johnc@2063 | 471 | // the updating and scanning of remembered sets. There are some |
johnc@2063 | 472 | // race conditions when these two operations are done in parallel |
johnc@2063 | 473 | // and they are causing failures. When we resolve said race |
johnc@2063 | 474 | // conditions, we'll revert back to parallel remembered set |
johnc@2063 | 475 | // updating and scanning. See CRs 6677707 and 6677708. |
johnc@2063 | 476 | if (G1UseParallelRSetUpdating || (worker_i == 0)) { |
johnc@2063 | 477 | updateRS(&into_cset_dcq, worker_i); |
ysr@777 | 478 | } else { |
johnc@2063 | 479 | _g1p->record_update_rs_processed_buffers(worker_i, 0.0); |
johnc@2063 | 480 | _g1p->record_update_rs_time(worker_i, 0.0); |
johnc@2063 | 481 | } |
johnc@2063 | 482 | if (G1UseParallelRSetScanning || (worker_i == 0)) { |
johnc@2063 | 483 | scanRS(oc, worker_i); |
johnc@2063 | 484 | } else { |
johnc@2063 | 485 | _g1p->record_scan_rs_time(worker_i, 0.0); |
ysr@777 | 486 | } |
johnc@2060 | 487 | |
johnc@2060 | 488 | // We now clear the cached values of _cset_rs_update_cl for this worker |
johnc@2060 | 489 | _cset_rs_update_cl[worker_i] = NULL; |
ysr@777 | 490 | } |
ysr@777 | 491 | |
johnc@2216 | 492 | void G1RemSet::prepare_for_oops_into_collection_set_do() { |
ysr@777 | 493 | #if G1_REM_SET_LOGGING |
ysr@777 | 494 | PrintRSClosure cl; |
ysr@777 | 495 | _g1->collection_set_iterate(&cl); |
ysr@777 | 496 | #endif |
ysr@777 | 497 | cleanupHRRS(); |
ysr@777 | 498 | ConcurrentG1Refine* cg1r = _g1->concurrent_g1_refine(); |
ysr@777 | 499 | _g1->set_refine_cte_cl_concurrency(false); |
ysr@777 | 500 | DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); |
ysr@777 | 501 | dcqs.concatenate_logs(); |
ysr@777 | 502 | |
ysr@777 | 503 | if (ParallelGCThreads > 0) { |
jmasa@2188 | 504 | _seq_task->set_n_threads((int)n_workers()); |
ysr@777 | 505 | } |
ysr@777 | 506 | guarantee( _cards_scanned == NULL, "invariant" ); |
ysr@777 | 507 | _cards_scanned = NEW_C_HEAP_ARRAY(size_t, n_workers()); |
apetrusenko@980 | 508 | for (uint i = 0; i < n_workers(); ++i) { |
apetrusenko@980 | 509 | _cards_scanned[i] = 0; |
apetrusenko@980 | 510 | } |
ysr@777 | 511 | _total_cards_scanned = 0; |
ysr@777 | 512 | } |
ysr@777 | 513 | |
ysr@777 | 514 | |
ysr@777 | 515 | class cleanUpIteratorsClosure : public HeapRegionClosure { |
ysr@777 | 516 | bool doHeapRegion(HeapRegion *r) { |
ysr@777 | 517 | HeapRegionRemSet* hrrs = r->rem_set(); |
ysr@777 | 518 | hrrs->init_for_par_iteration(); |
ysr@777 | 519 | return false; |
ysr@777 | 520 | } |
ysr@777 | 521 | }; |
ysr@777 | 522 | |
johnc@2060 | 523 | // This closure, applied to a DirtyCardQueueSet, is used to immediately |
johnc@2060 | 524 | // update the RSets for the regions in the CSet. For each card it iterates |
johnc@2060 | 525 | // through the oops which coincide with that card. It scans the reference |
johnc@2060 | 526 | // fields in each oop; when it finds an oop that points into the collection |
johnc@2060 | 527 | // set, the RSet for the region containing the referenced object is updated. |
johnc@2060 | 528 | class UpdateRSetCardTableEntryIntoCSetClosure: public CardTableEntryClosure { |
iveresov@1051 | 529 | G1CollectedHeap* _g1; |
johnc@2060 | 530 | CardTableModRefBS* _ct_bs; |
iveresov@1051 | 531 | public: |
johnc@2060 | 532 | UpdateRSetCardTableEntryIntoCSetClosure(G1CollectedHeap* g1, |
johnc@2060 | 533 | CardTableModRefBS* bs): |
johnc@2060 | 534 | _g1(g1), _ct_bs(bs) |
johnc@2060 | 535 | { } |
johnc@2060 | 536 | |
johnc@2060 | 537 | bool do_card_ptr(jbyte* card_ptr, int worker_i) { |
johnc@2060 | 538 | // Construct the region representing the card. |
johnc@2060 | 539 | HeapWord* start = _ct_bs->addr_for(card_ptr); |
johnc@2060 | 540 | // And find the region containing it. |
johnc@2060 | 541 | HeapRegion* r = _g1->heap_region_containing(start); |
johnc@2060 | 542 | assert(r != NULL, "unexpected null"); |
johnc@2060 | 543 | |
johnc@2060 | 544 | // Scan oops in the card looking for references into the collection set |
johnc@2060 | 545 | HeapWord* end = _ct_bs->addr_for(card_ptr + 1); |
johnc@2060 | 546 | MemRegion scanRegion(start, end); |
johnc@2060 | 547 | |
johnc@2060 | 548 | UpdateRSetImmediate update_rs_cl(_g1->g1_rem_set()); |
johnc@2060 | 549 | FilterIntoCSClosure update_rs_cset_oop_cl(NULL, _g1, &update_rs_cl); |
johnc@2060 | 550 | FilterOutOfRegionClosure filter_then_update_rs_cset_oop_cl(r, &update_rs_cset_oop_cl); |
johnc@2060 | 551 | |
johnc@2060 | 552 | // We can pass false as the "filter_young" parameter here as: |
johnc@2060 | 553 | // * we should be in a STW pause, |
johnc@2060 | 554 | // * the DCQS to which this closure is applied is used to hold |
johnc@2060 | 555 | // references that point into the collection set from the prior |
johnc@2060 | 556 | // RSet updating, |
johnc@2060 | 557 | // * the post-write barrier shouldn't be logging updates to young |
johnc@2060 | 558 | // regions (but there is a situation where this can happen - see |
johnc@2216 | 559 | // the comment in G1RemSet::concurrentRefineOneCard below - |
johnc@2060 | 560 | // that should not be applicable here), and |
johnc@2060 | 561 | // * during actual RSet updating, the filtering of cards in young |
johnc@2060 | 562 | // regions in HeapRegion::oops_on_card_seq_iterate_careful is |
johnc@2060 | 563 | // employed. |
johnc@2060 | 564 | // As a result, when this closure is applied to "refs into cset" |
johnc@2060 | 565 | // DCQS, we shouldn't see any cards in young regions. |
johnc@2060 | 566 | update_rs_cl.set_region(r); |
johnc@2060 | 567 | HeapWord* stop_point = |
johnc@2060 | 568 | r->oops_on_card_seq_iterate_careful(scanRegion, |
johnc@2060 | 569 | &filter_then_update_rs_cset_oop_cl, |
johnc@2060 | 570 | false /* filter_young */); |
johnc@2060 | 571 | |
johnc@2060 | 572 | // Since this is performed in the event of an evacuation failure, we |
johnc@2060 | 573 | // we shouldn't see a non-null stop point |
johnc@2060 | 574 | assert(stop_point == NULL, "saw an unallocated region"); |
johnc@2060 | 575 | return true; |
iveresov@1051 | 576 | } |
iveresov@1051 | 577 | }; |
iveresov@1051 | 578 | |
johnc@2216 | 579 | void G1RemSet::cleanup_after_oops_into_collection_set_do() { |
ysr@777 | 580 | guarantee( _cards_scanned != NULL, "invariant" ); |
ysr@777 | 581 | _total_cards_scanned = 0; |
ysr@777 | 582 | for (uint i = 0; i < n_workers(); ++i) |
ysr@777 | 583 | _total_cards_scanned += _cards_scanned[i]; |
ysr@777 | 584 | FREE_C_HEAP_ARRAY(size_t, _cards_scanned); |
ysr@777 | 585 | _cards_scanned = NULL; |
ysr@777 | 586 | // Cleanup after copy |
ysr@777 | 587 | #if G1_REM_SET_LOGGING |
ysr@777 | 588 | PrintRSClosure cl; |
ysr@777 | 589 | _g1->heap_region_iterate(&cl); |
ysr@777 | 590 | #endif |
ysr@777 | 591 | _g1->set_refine_cte_cl_concurrency(true); |
ysr@777 | 592 | cleanUpIteratorsClosure iterClosure; |
ysr@777 | 593 | _g1->collection_set_iterate(&iterClosure); |
ysr@777 | 594 | // Set all cards back to clean. |
ysr@777 | 595 | _g1->cleanUpCardTable(); |
iveresov@1229 | 596 | |
johnc@2060 | 597 | DirtyCardQueueSet& into_cset_dcqs = _g1->into_cset_dirty_card_queue_set(); |
johnc@2060 | 598 | int into_cset_n_buffers = into_cset_dcqs.completed_buffers_num(); |
johnc@2060 | 599 | |
iveresov@1051 | 600 | if (_g1->evacuation_failed()) { |
johnc@2060 | 601 | // Restore remembered sets for the regions pointing into the collection set. |
johnc@2060 | 602 | |
iveresov@1051 | 603 | if (G1DeferredRSUpdate) { |
johnc@2060 | 604 | // If deferred RS updates are enabled then we just need to transfer |
johnc@2060 | 605 | // the completed buffers from (a) the DirtyCardQueueSet used to hold |
johnc@2060 | 606 | // cards that contain references that point into the collection set |
johnc@2060 | 607 | // to (b) the DCQS used to hold the deferred RS updates |
johnc@2060 | 608 | _g1->dirty_card_queue_set().merge_bufferlists(&into_cset_dcqs); |
iveresov@1051 | 609 | } else { |
johnc@2060 | 610 | |
johnc@2060 | 611 | CardTableModRefBS* bs = (CardTableModRefBS*)_g1->barrier_set(); |
johnc@2060 | 612 | UpdateRSetCardTableEntryIntoCSetClosure update_rs_cset_immediate(_g1, bs); |
johnc@2060 | 613 | |
johnc@2060 | 614 | int n_completed_buffers = 0; |
johnc@2060 | 615 | while (into_cset_dcqs.apply_closure_to_completed_buffer(&update_rs_cset_immediate, |
johnc@2060 | 616 | 0, 0, true)) { |
johnc@2060 | 617 | n_completed_buffers++; |
johnc@2060 | 618 | } |
johnc@2060 | 619 | assert(n_completed_buffers == into_cset_n_buffers, "missed some buffers"); |
iveresov@1051 | 620 | } |
iveresov@1051 | 621 | } |
johnc@2060 | 622 | |
johnc@2060 | 623 | // Free any completed buffers in the DirtyCardQueueSet used to hold cards |
johnc@2060 | 624 | // which contain references that point into the collection. |
johnc@2060 | 625 | _g1->into_cset_dirty_card_queue_set().clear(); |
johnc@2060 | 626 | assert(_g1->into_cset_dirty_card_queue_set().completed_buffers_num() == 0, |
johnc@2060 | 627 | "all buffers should be freed"); |
johnc@2060 | 628 | _g1->into_cset_dirty_card_queue_set().clear_n_completed_buffers(); |
ysr@777 | 629 | } |
ysr@777 | 630 | |
ysr@777 | 631 | class ScrubRSClosure: public HeapRegionClosure { |
ysr@777 | 632 | G1CollectedHeap* _g1h; |
ysr@777 | 633 | BitMap* _region_bm; |
ysr@777 | 634 | BitMap* _card_bm; |
ysr@777 | 635 | CardTableModRefBS* _ctbs; |
ysr@777 | 636 | public: |
ysr@777 | 637 | ScrubRSClosure(BitMap* region_bm, BitMap* card_bm) : |
ysr@777 | 638 | _g1h(G1CollectedHeap::heap()), |
ysr@777 | 639 | _region_bm(region_bm), _card_bm(card_bm), |
ysr@777 | 640 | _ctbs(NULL) |
ysr@777 | 641 | { |
ysr@777 | 642 | ModRefBarrierSet* bs = _g1h->mr_bs(); |
ysr@777 | 643 | guarantee(bs->is_a(BarrierSet::CardTableModRef), "Precondition"); |
ysr@777 | 644 | _ctbs = (CardTableModRefBS*)bs; |
ysr@777 | 645 | } |
ysr@777 | 646 | |
ysr@777 | 647 | bool doHeapRegion(HeapRegion* r) { |
ysr@777 | 648 | if (!r->continuesHumongous()) { |
ysr@777 | 649 | r->rem_set()->scrub(_ctbs, _region_bm, _card_bm); |
ysr@777 | 650 | } |
ysr@777 | 651 | return false; |
ysr@777 | 652 | } |
ysr@777 | 653 | }; |
ysr@777 | 654 | |
johnc@2216 | 655 | void G1RemSet::scrub(BitMap* region_bm, BitMap* card_bm) { |
ysr@777 | 656 | ScrubRSClosure scrub_cl(region_bm, card_bm); |
ysr@777 | 657 | _g1->heap_region_iterate(&scrub_cl); |
ysr@777 | 658 | } |
ysr@777 | 659 | |
johnc@2216 | 660 | void G1RemSet::scrub_par(BitMap* region_bm, BitMap* card_bm, |
ysr@777 | 661 | int worker_num, int claim_val) { |
ysr@777 | 662 | ScrubRSClosure scrub_cl(region_bm, card_bm); |
ysr@777 | 663 | _g1->heap_region_par_iterate_chunked(&scrub_cl, worker_num, claim_val); |
ysr@777 | 664 | } |
ysr@777 | 665 | |
ysr@777 | 666 | |
ysr@777 | 667 | static IntHistogram out_of_histo(50, 50); |
ysr@777 | 668 | |
johnc@2060 | 669 | class TriggerClosure : public OopClosure { |
johnc@2060 | 670 | bool _trigger; |
johnc@2060 | 671 | public: |
johnc@2060 | 672 | TriggerClosure() : _trigger(false) { } |
johnc@2060 | 673 | bool value() const { return _trigger; } |
johnc@2060 | 674 | template <class T> void do_oop_nv(T* p) { _trigger = true; } |
johnc@2060 | 675 | virtual void do_oop(oop* p) { do_oop_nv(p); } |
johnc@2060 | 676 | virtual void do_oop(narrowOop* p) { do_oop_nv(p); } |
johnc@2060 | 677 | }; |
johnc@2060 | 678 | |
johnc@2060 | 679 | class InvokeIfNotTriggeredClosure: public OopClosure { |
johnc@2060 | 680 | TriggerClosure* _t; |
johnc@2060 | 681 | OopClosure* _oc; |
johnc@2060 | 682 | public: |
johnc@2060 | 683 | InvokeIfNotTriggeredClosure(TriggerClosure* t, OopClosure* oc): |
johnc@2060 | 684 | _t(t), _oc(oc) { } |
johnc@2060 | 685 | template <class T> void do_oop_nv(T* p) { |
johnc@2060 | 686 | if (!_t->value()) _oc->do_oop(p); |
johnc@2060 | 687 | } |
johnc@2060 | 688 | virtual void do_oop(oop* p) { do_oop_nv(p); } |
johnc@2060 | 689 | virtual void do_oop(narrowOop* p) { do_oop_nv(p); } |
johnc@2060 | 690 | }; |
johnc@2060 | 691 | |
johnc@2060 | 692 | class Mux2Closure : public OopClosure { |
johnc@2060 | 693 | OopClosure* _c1; |
johnc@2060 | 694 | OopClosure* _c2; |
johnc@2060 | 695 | public: |
johnc@2060 | 696 | Mux2Closure(OopClosure *c1, OopClosure *c2) : _c1(c1), _c2(c2) { } |
johnc@2060 | 697 | template <class T> void do_oop_nv(T* p) { |
johnc@2060 | 698 | _c1->do_oop(p); _c2->do_oop(p); |
johnc@2060 | 699 | } |
johnc@2060 | 700 | virtual void do_oop(oop* p) { do_oop_nv(p); } |
johnc@2060 | 701 | virtual void do_oop(narrowOop* p) { do_oop_nv(p); } |
johnc@2060 | 702 | }; |
johnc@2060 | 703 | |
johnc@2216 | 704 | bool G1RemSet::concurrentRefineOneCard_impl(jbyte* card_ptr, int worker_i, |
johnc@2060 | 705 | bool check_for_refs_into_cset) { |
johnc@1325 | 706 | // Construct the region representing the card. |
johnc@1325 | 707 | HeapWord* start = _ct_bs->addr_for(card_ptr); |
johnc@1325 | 708 | // And find the region containing it. |
johnc@1325 | 709 | HeapRegion* r = _g1->heap_region_containing(start); |
johnc@1325 | 710 | assert(r != NULL, "unexpected null"); |
johnc@1325 | 711 | |
johnc@1325 | 712 | HeapWord* end = _ct_bs->addr_for(card_ptr + 1); |
johnc@1325 | 713 | MemRegion dirtyRegion(start, end); |
johnc@1325 | 714 | |
johnc@1325 | 715 | #if CARD_REPEAT_HISTO |
johnc@2504 | 716 | init_ct_freq_table(_g1->max_capacity()); |
johnc@1325 | 717 | ct_freq_note_card(_ct_bs->index_for(start)); |
johnc@1325 | 718 | #endif |
johnc@1325 | 719 | |
johnc@2302 | 720 | assert(!check_for_refs_into_cset || _cset_rs_update_cl[worker_i] != NULL, "sanity"); |
johnc@2302 | 721 | UpdateRSOrPushRefOopClosure update_rs_oop_cl(_g1, |
johnc@2302 | 722 | _g1->g1_rem_set(), |
johnc@2302 | 723 | _cset_rs_update_cl[worker_i], |
johnc@2302 | 724 | check_for_refs_into_cset, |
johnc@2302 | 725 | worker_i); |
johnc@1325 | 726 | update_rs_oop_cl.set_from(r); |
johnc@2060 | 727 | |
johnc@2060 | 728 | TriggerClosure trigger_cl; |
johnc@2060 | 729 | FilterIntoCSClosure into_cs_cl(NULL, _g1, &trigger_cl); |
johnc@2060 | 730 | InvokeIfNotTriggeredClosure invoke_cl(&trigger_cl, &into_cs_cl); |
johnc@2060 | 731 | Mux2Closure mux(&invoke_cl, &update_rs_oop_cl); |
johnc@2060 | 732 | |
johnc@2060 | 733 | FilterOutOfRegionClosure filter_then_update_rs_oop_cl(r, |
johnc@2060 | 734 | (check_for_refs_into_cset ? |
johnc@2060 | 735 | (OopClosure*)&mux : |
johnc@2060 | 736 | (OopClosure*)&update_rs_oop_cl)); |
johnc@1325 | 737 | |
johnc@1325 | 738 | // Undirty the card. |
johnc@1325 | 739 | *card_ptr = CardTableModRefBS::clean_card_val(); |
johnc@1325 | 740 | // We must complete this write before we do any of the reads below. |
johnc@1325 | 741 | OrderAccess::storeload(); |
johnc@1325 | 742 | // And process it, being careful of unallocated portions of TLAB's. |
johnc@2021 | 743 | |
johnc@2021 | 744 | // The region for the current card may be a young region. The |
johnc@2021 | 745 | // current card may have been a card that was evicted from the |
johnc@2021 | 746 | // card cache. When the card was inserted into the cache, we had |
johnc@2021 | 747 | // determined that its region was non-young. While in the cache, |
johnc@2021 | 748 | // the region may have been freed during a cleanup pause, reallocated |
johnc@2021 | 749 | // and tagged as young. |
johnc@2021 | 750 | // |
johnc@2021 | 751 | // We wish to filter out cards for such a region but the current |
johnc@2021 | 752 | // thread, if we're running conucrrently, may "see" the young type |
johnc@2021 | 753 | // change at any time (so an earlier "is_young" check may pass or |
johnc@2021 | 754 | // fail arbitrarily). We tell the iteration code to perform this |
johnc@2021 | 755 | // filtering when it has been determined that there has been an actual |
johnc@2021 | 756 | // allocation in this region and making it safe to check the young type. |
johnc@2021 | 757 | bool filter_young = true; |
johnc@2021 | 758 | |
johnc@1325 | 759 | HeapWord* stop_point = |
johnc@1325 | 760 | r->oops_on_card_seq_iterate_careful(dirtyRegion, |
johnc@2021 | 761 | &filter_then_update_rs_oop_cl, |
johnc@2021 | 762 | filter_young); |
johnc@2021 | 763 | |
johnc@1325 | 764 | // If stop_point is non-null, then we encountered an unallocated region |
johnc@1325 | 765 | // (perhaps the unfilled portion of a TLAB.) For now, we'll dirty the |
johnc@1325 | 766 | // card and re-enqueue: if we put off the card until a GC pause, then the |
johnc@1325 | 767 | // unallocated portion will be filled in. Alternatively, we might try |
johnc@1325 | 768 | // the full complexity of the technique used in "regular" precleaning. |
johnc@1325 | 769 | if (stop_point != NULL) { |
johnc@1325 | 770 | // The card might have gotten re-dirtied and re-enqueued while we |
johnc@1325 | 771 | // worked. (In fact, it's pretty likely.) |
johnc@1325 | 772 | if (*card_ptr != CardTableModRefBS::dirty_card_val()) { |
johnc@1325 | 773 | *card_ptr = CardTableModRefBS::dirty_card_val(); |
johnc@1325 | 774 | MutexLockerEx x(Shared_DirtyCardQ_lock, |
johnc@1325 | 775 | Mutex::_no_safepoint_check_flag); |
johnc@1325 | 776 | DirtyCardQueue* sdcq = |
johnc@1325 | 777 | JavaThread::dirty_card_queue_set().shared_dirty_card_queue(); |
johnc@1325 | 778 | sdcq->enqueue(card_ptr); |
johnc@1325 | 779 | } |
johnc@1325 | 780 | } else { |
johnc@1325 | 781 | out_of_histo.add_entry(filter_then_update_rs_oop_cl.out_of_region()); |
johnc@1325 | 782 | _conc_refine_cards++; |
johnc@1325 | 783 | } |
johnc@2060 | 784 | |
johnc@2060 | 785 | return trigger_cl.value(); |
johnc@1325 | 786 | } |
johnc@1325 | 787 | |
johnc@2216 | 788 | bool G1RemSet::concurrentRefineOneCard(jbyte* card_ptr, int worker_i, |
johnc@2060 | 789 | bool check_for_refs_into_cset) { |
ysr@777 | 790 | // If the card is no longer dirty, nothing to do. |
johnc@2060 | 791 | if (*card_ptr != CardTableModRefBS::dirty_card_val()) { |
johnc@2060 | 792 | // No need to return that this card contains refs that point |
johnc@2060 | 793 | // into the collection set. |
johnc@2060 | 794 | return false; |
johnc@2060 | 795 | } |
ysr@777 | 796 | |
ysr@777 | 797 | // Construct the region representing the card. |
ysr@777 | 798 | HeapWord* start = _ct_bs->addr_for(card_ptr); |
ysr@777 | 799 | // And find the region containing it. |
ysr@777 | 800 | HeapRegion* r = _g1->heap_region_containing(start); |
ysr@777 | 801 | if (r == NULL) { |
ysr@777 | 802 | guarantee(_g1->is_in_permanent(start), "Or else where?"); |
johnc@2060 | 803 | // Again no need to return that this card contains refs that |
johnc@2060 | 804 | // point into the collection set. |
johnc@2060 | 805 | return false; // Not in the G1 heap (might be in perm, for example.) |
ysr@777 | 806 | } |
ysr@777 | 807 | // Why do we have to check here whether a card is on a young region, |
ysr@777 | 808 | // given that we dirty young regions and, as a result, the |
ysr@777 | 809 | // post-barrier is supposed to filter them out and never to enqueue |
ysr@777 | 810 | // them? When we allocate a new region as the "allocation region" we |
ysr@777 | 811 | // actually dirty its cards after we release the lock, since card |
ysr@777 | 812 | // dirtying while holding the lock was a performance bottleneck. So, |
ysr@777 | 813 | // as a result, it is possible for other threads to actually |
ysr@777 | 814 | // allocate objects in the region (after the acquire the lock) |
ysr@777 | 815 | // before all the cards on the region are dirtied. This is unlikely, |
ysr@777 | 816 | // and it doesn't happen often, but it can happen. So, the extra |
ysr@777 | 817 | // check below filters out those cards. |
iveresov@1072 | 818 | if (r->is_young()) { |
johnc@2060 | 819 | return false; |
ysr@777 | 820 | } |
ysr@777 | 821 | // While we are processing RSet buffers during the collection, we |
ysr@777 | 822 | // actually don't want to scan any cards on the collection set, |
ysr@777 | 823 | // since we don't want to update remebered sets with entries that |
ysr@777 | 824 | // point into the collection set, given that live objects from the |
ysr@777 | 825 | // collection set are about to move and such entries will be stale |
ysr@777 | 826 | // very soon. This change also deals with a reliability issue which |
ysr@777 | 827 | // involves scanning a card in the collection set and coming across |
ysr@777 | 828 | // an array that was being chunked and looking malformed. Note, |
ysr@777 | 829 | // however, that if evacuation fails, we have to scan any objects |
ysr@777 | 830 | // that were not moved and create any missing entries. |
ysr@777 | 831 | if (r->in_collection_set()) { |
johnc@2060 | 832 | return false; |
ysr@777 | 833 | } |
ysr@777 | 834 | |
johnc@1325 | 835 | // Should we defer processing the card? |
johnc@1325 | 836 | // |
johnc@1325 | 837 | // Previously the result from the insert_cache call would be |
johnc@1325 | 838 | // either card_ptr (implying that card_ptr was currently "cold"), |
johnc@1325 | 839 | // null (meaning we had inserted the card ptr into the "hot" |
johnc@1325 | 840 | // cache, which had some headroom), or a "hot" card ptr |
johnc@1325 | 841 | // extracted from the "hot" cache. |
johnc@1325 | 842 | // |
johnc@1325 | 843 | // Now that the _card_counts cache in the ConcurrentG1Refine |
johnc@1325 | 844 | // instance is an evicting hash table, the result we get back |
johnc@1325 | 845 | // could be from evicting the card ptr in an already occupied |
johnc@1325 | 846 | // bucket (in which case we have replaced the card ptr in the |
johnc@1325 | 847 | // bucket with card_ptr and "defer" is set to false). To avoid |
johnc@1325 | 848 | // having a data structure (updates to which would need a lock) |
johnc@1325 | 849 | // to hold these unprocessed dirty cards, we need to immediately |
johnc@1325 | 850 | // process card_ptr. The actions needed to be taken on return |
johnc@1325 | 851 | // from cache_insert are summarized in the following table: |
johnc@1325 | 852 | // |
johnc@1325 | 853 | // res defer action |
johnc@1325 | 854 | // -------------------------------------------------------------- |
johnc@1325 | 855 | // null false card evicted from _card_counts & replaced with |
johnc@1325 | 856 | // card_ptr; evicted ptr added to hot cache. |
johnc@1325 | 857 | // No need to process res; immediately process card_ptr |
johnc@1325 | 858 | // |
johnc@1325 | 859 | // null true card not evicted from _card_counts; card_ptr added |
johnc@1325 | 860 | // to hot cache. |
johnc@1325 | 861 | // Nothing to do. |
johnc@1325 | 862 | // |
johnc@1325 | 863 | // non-null false card evicted from _card_counts & replaced with |
johnc@1325 | 864 | // card_ptr; evicted ptr is currently "cold" or |
johnc@1325 | 865 | // caused an eviction from the hot cache. |
johnc@1325 | 866 | // Immediately process res; process card_ptr. |
johnc@1325 | 867 | // |
johnc@1325 | 868 | // non-null true card not evicted from _card_counts; card_ptr is |
johnc@1325 | 869 | // currently cold, or caused an eviction from hot |
johnc@1325 | 870 | // cache. |
johnc@1325 | 871 | // Immediately process res; no need to process card_ptr. |
johnc@1325 | 872 | |
johnc@2060 | 873 | |
johnc@1325 | 874 | jbyte* res = card_ptr; |
johnc@1325 | 875 | bool defer = false; |
johnc@2060 | 876 | |
johnc@2060 | 877 | // This gets set to true if the card being refined has references |
johnc@2060 | 878 | // that point into the collection set. |
johnc@2060 | 879 | bool oops_into_cset = false; |
johnc@2060 | 880 | |
ysr@777 | 881 | if (_cg1r->use_cache()) { |
johnc@1325 | 882 | jbyte* res = _cg1r->cache_insert(card_ptr, &defer); |
johnc@1325 | 883 | if (res != NULL && (res != card_ptr || defer)) { |
johnc@1325 | 884 | start = _ct_bs->addr_for(res); |
johnc@1325 | 885 | r = _g1->heap_region_containing(start); |
johnc@1325 | 886 | if (r == NULL) { |
johnc@1325 | 887 | assert(_g1->is_in_permanent(start), "Or else where?"); |
johnc@1325 | 888 | } else { |
johnc@2021 | 889 | // Checking whether the region we got back from the cache |
johnc@2021 | 890 | // is young here is inappropriate. The region could have been |
johnc@2021 | 891 | // freed, reallocated and tagged as young while in the cache. |
johnc@2021 | 892 | // Hence we could see its young type change at any time. |
johnc@2021 | 893 | // |
johnc@2021 | 894 | // Process card pointer we get back from the hot card cache. This |
johnc@2021 | 895 | // will check whether the region containing the card is young |
johnc@2021 | 896 | // _after_ checking that the region has been allocated from. |
johnc@2060 | 897 | oops_into_cset = concurrentRefineOneCard_impl(res, worker_i, |
johnc@2060 | 898 | false /* check_for_refs_into_cset */); |
johnc@2060 | 899 | // The above call to concurrentRefineOneCard_impl is only |
johnc@2060 | 900 | // performed if the hot card cache is enabled. This cache is |
johnc@2060 | 901 | // disabled during an evacuation pause - which is the only |
johnc@2060 | 902 | // time when we need know if the card contains references |
johnc@2060 | 903 | // that point into the collection set. Also when the hot card |
johnc@2060 | 904 | // cache is enabled, this code is executed by the concurrent |
johnc@2060 | 905 | // refine threads - rather than the GC worker threads - and |
johnc@2060 | 906 | // concurrentRefineOneCard_impl will return false. |
johnc@2060 | 907 | assert(!oops_into_cset, "should not see true here"); |
johnc@1325 | 908 | } |
ysr@777 | 909 | } |
ysr@777 | 910 | } |
ysr@777 | 911 | |
johnc@1325 | 912 | if (!defer) { |
johnc@2060 | 913 | oops_into_cset = |
johnc@2060 | 914 | concurrentRefineOneCard_impl(card_ptr, worker_i, check_for_refs_into_cset); |
johnc@2060 | 915 | // We should only be detecting that the card contains references |
johnc@2060 | 916 | // that point into the collection set if the current thread is |
johnc@2060 | 917 | // a GC worker thread. |
johnc@2060 | 918 | assert(!oops_into_cset || SafepointSynchronize::is_at_safepoint(), |
johnc@2060 | 919 | "invalid result at non safepoint"); |
ysr@777 | 920 | } |
johnc@2060 | 921 | return oops_into_cset; |
ysr@777 | 922 | } |
ysr@777 | 923 | |
ysr@777 | 924 | class HRRSStatsIter: public HeapRegionClosure { |
ysr@777 | 925 | size_t _occupied; |
ysr@777 | 926 | size_t _total_mem_sz; |
ysr@777 | 927 | size_t _max_mem_sz; |
ysr@777 | 928 | HeapRegion* _max_mem_sz_region; |
ysr@777 | 929 | public: |
ysr@777 | 930 | HRRSStatsIter() : |
ysr@777 | 931 | _occupied(0), |
ysr@777 | 932 | _total_mem_sz(0), |
ysr@777 | 933 | _max_mem_sz(0), |
ysr@777 | 934 | _max_mem_sz_region(NULL) |
ysr@777 | 935 | {} |
ysr@777 | 936 | |
ysr@777 | 937 | bool doHeapRegion(HeapRegion* r) { |
ysr@777 | 938 | if (r->continuesHumongous()) return false; |
ysr@777 | 939 | size_t mem_sz = r->rem_set()->mem_size(); |
ysr@777 | 940 | if (mem_sz > _max_mem_sz) { |
ysr@777 | 941 | _max_mem_sz = mem_sz; |
ysr@777 | 942 | _max_mem_sz_region = r; |
ysr@777 | 943 | } |
ysr@777 | 944 | _total_mem_sz += mem_sz; |
ysr@777 | 945 | size_t occ = r->rem_set()->occupied(); |
ysr@777 | 946 | _occupied += occ; |
ysr@777 | 947 | return false; |
ysr@777 | 948 | } |
ysr@777 | 949 | size_t total_mem_sz() { return _total_mem_sz; } |
ysr@777 | 950 | size_t max_mem_sz() { return _max_mem_sz; } |
ysr@777 | 951 | size_t occupied() { return _occupied; } |
ysr@777 | 952 | HeapRegion* max_mem_sz_region() { return _max_mem_sz_region; } |
ysr@777 | 953 | }; |
ysr@777 | 954 | |
iveresov@1229 | 955 | class PrintRSThreadVTimeClosure : public ThreadClosure { |
iveresov@1229 | 956 | public: |
iveresov@1229 | 957 | virtual void do_thread(Thread *t) { |
iveresov@1229 | 958 | ConcurrentG1RefineThread* crt = (ConcurrentG1RefineThread*) t; |
iveresov@1229 | 959 | gclog_or_tty->print(" %5.2f", crt->vtime_accum()); |
iveresov@1229 | 960 | } |
iveresov@1229 | 961 | }; |
iveresov@1229 | 962 | |
johnc@2216 | 963 | void G1RemSet::print_summary_info() { |
ysr@777 | 964 | G1CollectedHeap* g1 = G1CollectedHeap::heap(); |
ysr@777 | 965 | |
ysr@777 | 966 | #if CARD_REPEAT_HISTO |
ysr@777 | 967 | gclog_or_tty->print_cr("\nG1 card_repeat count histogram: "); |
ysr@777 | 968 | gclog_or_tty->print_cr(" # of repeats --> # of cards with that number."); |
ysr@777 | 969 | card_repeat_count.print_on(gclog_or_tty); |
ysr@777 | 970 | #endif |
ysr@777 | 971 | |
ysr@777 | 972 | if (FILTEROUTOFREGIONCLOSURE_DOHISTOGRAMCOUNT) { |
ysr@777 | 973 | gclog_or_tty->print_cr("\nG1 rem-set out-of-region histogram: "); |
ysr@777 | 974 | gclog_or_tty->print_cr(" # of CS ptrs --> # of cards with that number."); |
ysr@777 | 975 | out_of_histo.print_on(gclog_or_tty); |
ysr@777 | 976 | } |
iveresov@1229 | 977 | gclog_or_tty->print_cr("\n Concurrent RS processed %d cards", |
iveresov@1229 | 978 | _conc_refine_cards); |
ysr@777 | 979 | DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); |
ysr@777 | 980 | jint tot_processed_buffers = |
ysr@777 | 981 | dcqs.processed_buffers_mut() + dcqs.processed_buffers_rs_thread(); |
ysr@777 | 982 | gclog_or_tty->print_cr(" Of %d completed buffers:", tot_processed_buffers); |
iveresov@1229 | 983 | gclog_or_tty->print_cr(" %8d (%5.1f%%) by conc RS threads.", |
ysr@777 | 984 | dcqs.processed_buffers_rs_thread(), |
ysr@777 | 985 | 100.0*(float)dcqs.processed_buffers_rs_thread()/ |
ysr@777 | 986 | (float)tot_processed_buffers); |
ysr@777 | 987 | gclog_or_tty->print_cr(" %8d (%5.1f%%) by mutator threads.", |
ysr@777 | 988 | dcqs.processed_buffers_mut(), |
ysr@777 | 989 | 100.0*(float)dcqs.processed_buffers_mut()/ |
ysr@777 | 990 | (float)tot_processed_buffers); |
iveresov@1229 | 991 | gclog_or_tty->print_cr(" Conc RS threads times(s)"); |
iveresov@1229 | 992 | PrintRSThreadVTimeClosure p; |
iveresov@1229 | 993 | gclog_or_tty->print(" "); |
iveresov@1229 | 994 | g1->concurrent_g1_refine()->threads_do(&p); |
ysr@777 | 995 | gclog_or_tty->print_cr(""); |
iveresov@1229 | 996 | |
johnc@2216 | 997 | HRRSStatsIter blk; |
johnc@2216 | 998 | g1->heap_region_iterate(&blk); |
johnc@2216 | 999 | gclog_or_tty->print_cr(" Total heap region rem set sizes = " SIZE_FORMAT "K." |
johnc@2216 | 1000 | " Max = " SIZE_FORMAT "K.", |
johnc@2216 | 1001 | blk.total_mem_sz()/K, blk.max_mem_sz()/K); |
johnc@2216 | 1002 | gclog_or_tty->print_cr(" Static structures = " SIZE_FORMAT "K," |
johnc@2216 | 1003 | " free_lists = " SIZE_FORMAT "K.", |
johnc@2216 | 1004 | HeapRegionRemSet::static_mem_size()/K, |
johnc@2216 | 1005 | HeapRegionRemSet::fl_mem_size()/K); |
johnc@2216 | 1006 | gclog_or_tty->print_cr(" %d occupied cards represented.", |
johnc@2216 | 1007 | blk.occupied()); |
johnc@2216 | 1008 | gclog_or_tty->print_cr(" Max sz region = [" PTR_FORMAT ", " PTR_FORMAT " )" |
johnc@2216 | 1009 | ", cap = " SIZE_FORMAT "K, occ = " SIZE_FORMAT "K.", |
johnc@2216 | 1010 | blk.max_mem_sz_region()->bottom(), blk.max_mem_sz_region()->end(), |
johnc@2216 | 1011 | (blk.max_mem_sz_region()->rem_set()->mem_size() + K - 1)/K, |
johnc@2216 | 1012 | (blk.max_mem_sz_region()->rem_set()->occupied() + K - 1)/K); |
johnc@2216 | 1013 | gclog_or_tty->print_cr(" Did %d coarsenings.", HeapRegionRemSet::n_coarsenings()); |
ysr@777 | 1014 | } |
johnc@2060 | 1015 | |
johnc@2216 | 1016 | void G1RemSet::prepare_for_verify() { |
iveresov@1072 | 1017 | if (G1HRRSFlushLogBuffersOnVerify && |
iveresov@1072 | 1018 | (VerifyBeforeGC || VerifyAfterGC) |
iveresov@1072 | 1019 | && !_g1->full_collection()) { |
ysr@777 | 1020 | cleanupHRRS(); |
ysr@777 | 1021 | _g1->set_refine_cte_cl_concurrency(false); |
ysr@777 | 1022 | if (SafepointSynchronize::is_at_safepoint()) { |
ysr@777 | 1023 | DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); |
ysr@777 | 1024 | dcqs.concatenate_logs(); |
ysr@777 | 1025 | } |
ysr@777 | 1026 | bool cg1r_use_cache = _cg1r->use_cache(); |
ysr@777 | 1027 | _cg1r->set_use_cache(false); |
johnc@2060 | 1028 | DirtyCardQueue into_cset_dcq(&_g1->into_cset_dirty_card_queue_set()); |
johnc@2060 | 1029 | updateRS(&into_cset_dcq, 0); |
johnc@2060 | 1030 | _g1->into_cset_dirty_card_queue_set().clear(); |
ysr@777 | 1031 | _cg1r->set_use_cache(cg1r_use_cache); |
iveresov@1072 | 1032 | |
iveresov@1072 | 1033 | assert(JavaThread::dirty_card_queue_set().completed_buffers_num() == 0, "All should be consumed"); |
ysr@777 | 1034 | } |
ysr@777 | 1035 | } |