src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp

Mon, 13 Oct 2008 21:41:42 -0700

author
iveresov
date
Mon, 13 Oct 2008 21:41:42 -0700
changeset 828
078b8a0d8d7c
parent 825
cc68c8e9b309
child 888
c96030fff130
permissions
-rw-r--r--

6758633: G1: SEGV with GCOld on Linux
Summary: Avoid growth of a GrowableArray backend of HeapRegionSeq.
Reviewed-by: tonyp, jcoomes

ysr@777 1 /*
ysr@777 2 * Copyright 2001-2007 Sun Microsystems, Inc. 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 *
ysr@777 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
ysr@777 20 * CA 95054 USA or visit www.sun.com if you need additional information or
ysr@777 21 * have any questions.
ysr@777 22 *
ysr@777 23 */
ysr@777 24
ysr@777 25 #include "incls/_precompiled.incl"
ysr@777 26 #include "incls/_g1CollectedHeap.cpp.incl"
ysr@777 27
ysr@777 28 // turn it on so that the contents of the young list (scan-only /
ysr@777 29 // to-be-collected) are printed at "strategic" points before / during
ysr@777 30 // / after the collection --- this is useful for debugging
ysr@777 31 #define SCAN_ONLY_VERBOSE 0
ysr@777 32 // CURRENT STATUS
ysr@777 33 // This file is under construction. Search for "FIXME".
ysr@777 34
ysr@777 35 // INVARIANTS/NOTES
ysr@777 36 //
ysr@777 37 // All allocation activity covered by the G1CollectedHeap interface is
ysr@777 38 // serialized by acquiring the HeapLock. This happens in
ysr@777 39 // mem_allocate_work, which all such allocation functions call.
ysr@777 40 // (Note that this does not apply to TLAB allocation, which is not part
ysr@777 41 // of this interface: it is done by clients of this interface.)
ysr@777 42
ysr@777 43 // Local to this file.
ysr@777 44
ysr@777 45 // Finds the first HeapRegion.
ysr@777 46 // No longer used, but might be handy someday.
ysr@777 47
ysr@777 48 class FindFirstRegionClosure: public HeapRegionClosure {
ysr@777 49 HeapRegion* _a_region;
ysr@777 50 public:
ysr@777 51 FindFirstRegionClosure() : _a_region(NULL) {}
ysr@777 52 bool doHeapRegion(HeapRegion* r) {
ysr@777 53 _a_region = r;
ysr@777 54 return true;
ysr@777 55 }
ysr@777 56 HeapRegion* result() { return _a_region; }
ysr@777 57 };
ysr@777 58
ysr@777 59
ysr@777 60 class RefineCardTableEntryClosure: public CardTableEntryClosure {
ysr@777 61 SuspendibleThreadSet* _sts;
ysr@777 62 G1RemSet* _g1rs;
ysr@777 63 ConcurrentG1Refine* _cg1r;
ysr@777 64 bool _concurrent;
ysr@777 65 public:
ysr@777 66 RefineCardTableEntryClosure(SuspendibleThreadSet* sts,
ysr@777 67 G1RemSet* g1rs,
ysr@777 68 ConcurrentG1Refine* cg1r) :
ysr@777 69 _sts(sts), _g1rs(g1rs), _cg1r(cg1r), _concurrent(true)
ysr@777 70 {}
ysr@777 71 bool do_card_ptr(jbyte* card_ptr, int worker_i) {
ysr@777 72 _g1rs->concurrentRefineOneCard(card_ptr, worker_i);
ysr@777 73 if (_concurrent && _sts->should_yield()) {
ysr@777 74 // Caller will actually yield.
ysr@777 75 return false;
ysr@777 76 }
ysr@777 77 // Otherwise, we finished successfully; return true.
ysr@777 78 return true;
ysr@777 79 }
ysr@777 80 void set_concurrent(bool b) { _concurrent = b; }
ysr@777 81 };
ysr@777 82
ysr@777 83
ysr@777 84 class ClearLoggedCardTableEntryClosure: public CardTableEntryClosure {
ysr@777 85 int _calls;
ysr@777 86 G1CollectedHeap* _g1h;
ysr@777 87 CardTableModRefBS* _ctbs;
ysr@777 88 int _histo[256];
ysr@777 89 public:
ysr@777 90 ClearLoggedCardTableEntryClosure() :
ysr@777 91 _calls(0)
ysr@777 92 {
ysr@777 93 _g1h = G1CollectedHeap::heap();
ysr@777 94 _ctbs = (CardTableModRefBS*)_g1h->barrier_set();
ysr@777 95 for (int i = 0; i < 256; i++) _histo[i] = 0;
ysr@777 96 }
ysr@777 97 bool do_card_ptr(jbyte* card_ptr, int worker_i) {
ysr@777 98 if (_g1h->is_in_reserved(_ctbs->addr_for(card_ptr))) {
ysr@777 99 _calls++;
ysr@777 100 unsigned char* ujb = (unsigned char*)card_ptr;
ysr@777 101 int ind = (int)(*ujb);
ysr@777 102 _histo[ind]++;
ysr@777 103 *card_ptr = -1;
ysr@777 104 }
ysr@777 105 return true;
ysr@777 106 }
ysr@777 107 int calls() { return _calls; }
ysr@777 108 void print_histo() {
ysr@777 109 gclog_or_tty->print_cr("Card table value histogram:");
ysr@777 110 for (int i = 0; i < 256; i++) {
ysr@777 111 if (_histo[i] != 0) {
ysr@777 112 gclog_or_tty->print_cr(" %d: %d", i, _histo[i]);
ysr@777 113 }
ysr@777 114 }
ysr@777 115 }
ysr@777 116 };
ysr@777 117
ysr@777 118 class RedirtyLoggedCardTableEntryClosure: public CardTableEntryClosure {
ysr@777 119 int _calls;
ysr@777 120 G1CollectedHeap* _g1h;
ysr@777 121 CardTableModRefBS* _ctbs;
ysr@777 122 public:
ysr@777 123 RedirtyLoggedCardTableEntryClosure() :
ysr@777 124 _calls(0)
ysr@777 125 {
ysr@777 126 _g1h = G1CollectedHeap::heap();
ysr@777 127 _ctbs = (CardTableModRefBS*)_g1h->barrier_set();
ysr@777 128 }
ysr@777 129 bool do_card_ptr(jbyte* card_ptr, int worker_i) {
ysr@777 130 if (_g1h->is_in_reserved(_ctbs->addr_for(card_ptr))) {
ysr@777 131 _calls++;
ysr@777 132 *card_ptr = 0;
ysr@777 133 }
ysr@777 134 return true;
ysr@777 135 }
ysr@777 136 int calls() { return _calls; }
ysr@777 137 };
ysr@777 138
ysr@777 139 YoungList::YoungList(G1CollectedHeap* g1h)
ysr@777 140 : _g1h(g1h), _head(NULL),
ysr@777 141 _scan_only_head(NULL), _scan_only_tail(NULL), _curr_scan_only(NULL),
ysr@777 142 _length(0), _scan_only_length(0),
ysr@777 143 _last_sampled_rs_lengths(0),
ysr@777 144 _survivor_head(NULL), _survivors_tail(NULL), _survivor_length(0)
ysr@777 145 {
ysr@777 146 guarantee( check_list_empty(false), "just making sure..." );
ysr@777 147 }
ysr@777 148
ysr@777 149 void YoungList::push_region(HeapRegion *hr) {
ysr@777 150 assert(!hr->is_young(), "should not already be young");
ysr@777 151 assert(hr->get_next_young_region() == NULL, "cause it should!");
ysr@777 152
ysr@777 153 hr->set_next_young_region(_head);
ysr@777 154 _head = hr;
ysr@777 155
ysr@777 156 hr->set_young();
ysr@777 157 double yg_surv_rate = _g1h->g1_policy()->predict_yg_surv_rate((int)_length);
ysr@777 158 ++_length;
ysr@777 159 }
ysr@777 160
ysr@777 161 void YoungList::add_survivor_region(HeapRegion* hr) {
ysr@777 162 assert(!hr->is_survivor(), "should not already be for survived");
ysr@777 163 assert(hr->get_next_young_region() == NULL, "cause it should!");
ysr@777 164
ysr@777 165 hr->set_next_young_region(_survivor_head);
ysr@777 166 if (_survivor_head == NULL) {
ysr@777 167 _survivors_tail = hr;
ysr@777 168 }
ysr@777 169 _survivor_head = hr;
ysr@777 170
ysr@777 171 hr->set_survivor();
ysr@777 172 ++_survivor_length;
ysr@777 173 }
ysr@777 174
ysr@777 175 HeapRegion* YoungList::pop_region() {
ysr@777 176 while (_head != NULL) {
ysr@777 177 assert( length() > 0, "list should not be empty" );
ysr@777 178 HeapRegion* ret = _head;
ysr@777 179 _head = ret->get_next_young_region();
ysr@777 180 ret->set_next_young_region(NULL);
ysr@777 181 --_length;
ysr@777 182 assert(ret->is_young(), "region should be very young");
ysr@777 183
ysr@777 184 // Replace 'Survivor' region type with 'Young'. So the region will
ysr@777 185 // be treated as a young region and will not be 'confused' with
ysr@777 186 // newly created survivor regions.
ysr@777 187 if (ret->is_survivor()) {
ysr@777 188 ret->set_young();
ysr@777 189 }
ysr@777 190
ysr@777 191 if (!ret->is_scan_only()) {
ysr@777 192 return ret;
ysr@777 193 }
ysr@777 194
ysr@777 195 // scan-only, we'll add it to the scan-only list
ysr@777 196 if (_scan_only_tail == NULL) {
ysr@777 197 guarantee( _scan_only_head == NULL, "invariant" );
ysr@777 198
ysr@777 199 _scan_only_head = ret;
ysr@777 200 _curr_scan_only = ret;
ysr@777 201 } else {
ysr@777 202 guarantee( _scan_only_head != NULL, "invariant" );
ysr@777 203 _scan_only_tail->set_next_young_region(ret);
ysr@777 204 }
ysr@777 205 guarantee( ret->get_next_young_region() == NULL, "invariant" );
ysr@777 206 _scan_only_tail = ret;
ysr@777 207
ysr@777 208 // no need to be tagged as scan-only any more
ysr@777 209 ret->set_young();
ysr@777 210
ysr@777 211 ++_scan_only_length;
ysr@777 212 }
ysr@777 213 assert( length() == 0, "list should be empty" );
ysr@777 214 return NULL;
ysr@777 215 }
ysr@777 216
ysr@777 217 void YoungList::empty_list(HeapRegion* list) {
ysr@777 218 while (list != NULL) {
ysr@777 219 HeapRegion* next = list->get_next_young_region();
ysr@777 220 list->set_next_young_region(NULL);
ysr@777 221 list->uninstall_surv_rate_group();
ysr@777 222 list->set_not_young();
ysr@777 223 list = next;
ysr@777 224 }
ysr@777 225 }
ysr@777 226
ysr@777 227 void YoungList::empty_list() {
ysr@777 228 assert(check_list_well_formed(), "young list should be well formed");
ysr@777 229
ysr@777 230 empty_list(_head);
ysr@777 231 _head = NULL;
ysr@777 232 _length = 0;
ysr@777 233
ysr@777 234 empty_list(_scan_only_head);
ysr@777 235 _scan_only_head = NULL;
ysr@777 236 _scan_only_tail = NULL;
ysr@777 237 _scan_only_length = 0;
ysr@777 238 _curr_scan_only = NULL;
ysr@777 239
ysr@777 240 empty_list(_survivor_head);
ysr@777 241 _survivor_head = NULL;
ysr@777 242 _survivors_tail = NULL;
ysr@777 243 _survivor_length = 0;
ysr@777 244
ysr@777 245 _last_sampled_rs_lengths = 0;
ysr@777 246
ysr@777 247 assert(check_list_empty(false), "just making sure...");
ysr@777 248 }
ysr@777 249
ysr@777 250 bool YoungList::check_list_well_formed() {
ysr@777 251 bool ret = true;
ysr@777 252
ysr@777 253 size_t length = 0;
ysr@777 254 HeapRegion* curr = _head;
ysr@777 255 HeapRegion* last = NULL;
ysr@777 256 while (curr != NULL) {
ysr@777 257 if (!curr->is_young() || curr->is_scan_only()) {
ysr@777 258 gclog_or_tty->print_cr("### YOUNG REGION "PTR_FORMAT"-"PTR_FORMAT" "
ysr@777 259 "incorrectly tagged (%d, %d)",
ysr@777 260 curr->bottom(), curr->end(),
ysr@777 261 curr->is_young(), curr->is_scan_only());
ysr@777 262 ret = false;
ysr@777 263 }
ysr@777 264 ++length;
ysr@777 265 last = curr;
ysr@777 266 curr = curr->get_next_young_region();
ysr@777 267 }
ysr@777 268 ret = ret && (length == _length);
ysr@777 269
ysr@777 270 if (!ret) {
ysr@777 271 gclog_or_tty->print_cr("### YOUNG LIST seems not well formed!");
ysr@777 272 gclog_or_tty->print_cr("### list has %d entries, _length is %d",
ysr@777 273 length, _length);
ysr@777 274 }
ysr@777 275
ysr@777 276 bool scan_only_ret = true;
ysr@777 277 length = 0;
ysr@777 278 curr = _scan_only_head;
ysr@777 279 last = NULL;
ysr@777 280 while (curr != NULL) {
ysr@777 281 if (!curr->is_young() || curr->is_scan_only()) {
ysr@777 282 gclog_or_tty->print_cr("### SCAN-ONLY REGION "PTR_FORMAT"-"PTR_FORMAT" "
ysr@777 283 "incorrectly tagged (%d, %d)",
ysr@777 284 curr->bottom(), curr->end(),
ysr@777 285 curr->is_young(), curr->is_scan_only());
ysr@777 286 scan_only_ret = false;
ysr@777 287 }
ysr@777 288 ++length;
ysr@777 289 last = curr;
ysr@777 290 curr = curr->get_next_young_region();
ysr@777 291 }
ysr@777 292 scan_only_ret = scan_only_ret && (length == _scan_only_length);
ysr@777 293
ysr@777 294 if ( (last != _scan_only_tail) ||
ysr@777 295 (_scan_only_head == NULL && _scan_only_tail != NULL) ||
ysr@777 296 (_scan_only_head != NULL && _scan_only_tail == NULL) ) {
ysr@777 297 gclog_or_tty->print_cr("## _scan_only_tail is set incorrectly");
ysr@777 298 scan_only_ret = false;
ysr@777 299 }
ysr@777 300
ysr@777 301 if (_curr_scan_only != NULL && _curr_scan_only != _scan_only_head) {
ysr@777 302 gclog_or_tty->print_cr("### _curr_scan_only is set incorrectly");
ysr@777 303 scan_only_ret = false;
ysr@777 304 }
ysr@777 305
ysr@777 306 if (!scan_only_ret) {
ysr@777 307 gclog_or_tty->print_cr("### SCAN-ONLY LIST seems not well formed!");
ysr@777 308 gclog_or_tty->print_cr("### list has %d entries, _scan_only_length is %d",
ysr@777 309 length, _scan_only_length);
ysr@777 310 }
ysr@777 311
ysr@777 312 return ret && scan_only_ret;
ysr@777 313 }
ysr@777 314
ysr@777 315 bool YoungList::check_list_empty(bool ignore_scan_only_list,
ysr@777 316 bool check_sample) {
ysr@777 317 bool ret = true;
ysr@777 318
ysr@777 319 if (_length != 0) {
ysr@777 320 gclog_or_tty->print_cr("### YOUNG LIST should have 0 length, not %d",
ysr@777 321 _length);
ysr@777 322 ret = false;
ysr@777 323 }
ysr@777 324 if (check_sample && _last_sampled_rs_lengths != 0) {
ysr@777 325 gclog_or_tty->print_cr("### YOUNG LIST has non-zero last sampled RS lengths");
ysr@777 326 ret = false;
ysr@777 327 }
ysr@777 328 if (_head != NULL) {
ysr@777 329 gclog_or_tty->print_cr("### YOUNG LIST does not have a NULL head");
ysr@777 330 ret = false;
ysr@777 331 }
ysr@777 332 if (!ret) {
ysr@777 333 gclog_or_tty->print_cr("### YOUNG LIST does not seem empty");
ysr@777 334 }
ysr@777 335
ysr@777 336 if (ignore_scan_only_list)
ysr@777 337 return ret;
ysr@777 338
ysr@777 339 bool scan_only_ret = true;
ysr@777 340 if (_scan_only_length != 0) {
ysr@777 341 gclog_or_tty->print_cr("### SCAN-ONLY LIST should have 0 length, not %d",
ysr@777 342 _scan_only_length);
ysr@777 343 scan_only_ret = false;
ysr@777 344 }
ysr@777 345 if (_scan_only_head != NULL) {
ysr@777 346 gclog_or_tty->print_cr("### SCAN-ONLY LIST does not have a NULL head");
ysr@777 347 scan_only_ret = false;
ysr@777 348 }
ysr@777 349 if (_scan_only_tail != NULL) {
ysr@777 350 gclog_or_tty->print_cr("### SCAN-ONLY LIST does not have a NULL tail");
ysr@777 351 scan_only_ret = false;
ysr@777 352 }
ysr@777 353 if (!scan_only_ret) {
ysr@777 354 gclog_or_tty->print_cr("### SCAN-ONLY LIST does not seem empty");
ysr@777 355 }
ysr@777 356
ysr@777 357 return ret && scan_only_ret;
ysr@777 358 }
ysr@777 359
ysr@777 360 void
ysr@777 361 YoungList::rs_length_sampling_init() {
ysr@777 362 _sampled_rs_lengths = 0;
ysr@777 363 _curr = _head;
ysr@777 364 }
ysr@777 365
ysr@777 366 bool
ysr@777 367 YoungList::rs_length_sampling_more() {
ysr@777 368 return _curr != NULL;
ysr@777 369 }
ysr@777 370
ysr@777 371 void
ysr@777 372 YoungList::rs_length_sampling_next() {
ysr@777 373 assert( _curr != NULL, "invariant" );
ysr@777 374 _sampled_rs_lengths += _curr->rem_set()->occupied();
ysr@777 375 _curr = _curr->get_next_young_region();
ysr@777 376 if (_curr == NULL) {
ysr@777 377 _last_sampled_rs_lengths = _sampled_rs_lengths;
ysr@777 378 // gclog_or_tty->print_cr("last sampled RS lengths = %d", _last_sampled_rs_lengths);
ysr@777 379 }
ysr@777 380 }
ysr@777 381
ysr@777 382 void
ysr@777 383 YoungList::reset_auxilary_lists() {
ysr@777 384 // We could have just "moved" the scan-only list to the young list.
ysr@777 385 // However, the scan-only list is ordered according to the region
ysr@777 386 // age in descending order, so, by moving one entry at a time, we
ysr@777 387 // ensure that it is recreated in ascending order.
ysr@777 388
ysr@777 389 guarantee( is_empty(), "young list should be empty" );
ysr@777 390 assert(check_list_well_formed(), "young list should be well formed");
ysr@777 391
ysr@777 392 // Add survivor regions to SurvRateGroup.
ysr@777 393 _g1h->g1_policy()->note_start_adding_survivor_regions();
ysr@777 394 for (HeapRegion* curr = _survivor_head;
ysr@777 395 curr != NULL;
ysr@777 396 curr = curr->get_next_young_region()) {
ysr@777 397 _g1h->g1_policy()->set_region_survivors(curr);
ysr@777 398 }
ysr@777 399 _g1h->g1_policy()->note_stop_adding_survivor_regions();
ysr@777 400
ysr@777 401 if (_survivor_head != NULL) {
ysr@777 402 _head = _survivor_head;
ysr@777 403 _length = _survivor_length + _scan_only_length;
ysr@777 404 _survivors_tail->set_next_young_region(_scan_only_head);
ysr@777 405 } else {
ysr@777 406 _head = _scan_only_head;
ysr@777 407 _length = _scan_only_length;
ysr@777 408 }
ysr@777 409
ysr@777 410 for (HeapRegion* curr = _scan_only_head;
ysr@777 411 curr != NULL;
ysr@777 412 curr = curr->get_next_young_region()) {
ysr@777 413 curr->recalculate_age_in_surv_rate_group();
ysr@777 414 }
ysr@777 415 _scan_only_head = NULL;
ysr@777 416 _scan_only_tail = NULL;
ysr@777 417 _scan_only_length = 0;
ysr@777 418 _curr_scan_only = NULL;
ysr@777 419
ysr@777 420 _survivor_head = NULL;
ysr@777 421 _survivors_tail = NULL;
ysr@777 422 _survivor_length = 0;
ysr@777 423 _g1h->g1_policy()->finished_recalculating_age_indexes();
ysr@777 424
ysr@777 425 assert(check_list_well_formed(), "young list should be well formed");
ysr@777 426 }
ysr@777 427
ysr@777 428 void YoungList::print() {
ysr@777 429 HeapRegion* lists[] = {_head, _scan_only_head, _survivor_head};
ysr@777 430 const char* names[] = {"YOUNG", "SCAN-ONLY", "SURVIVOR"};
ysr@777 431
ysr@777 432 for (unsigned int list = 0; list < ARRAY_SIZE(lists); ++list) {
ysr@777 433 gclog_or_tty->print_cr("%s LIST CONTENTS", names[list]);
ysr@777 434 HeapRegion *curr = lists[list];
ysr@777 435 if (curr == NULL)
ysr@777 436 gclog_or_tty->print_cr(" empty");
ysr@777 437 while (curr != NULL) {
ysr@777 438 gclog_or_tty->print_cr(" [%08x-%08x], t: %08x, P: %08x, N: %08x, C: %08x, "
ysr@777 439 "age: %4d, y: %d, s-o: %d, surv: %d",
ysr@777 440 curr->bottom(), curr->end(),
ysr@777 441 curr->top(),
ysr@777 442 curr->prev_top_at_mark_start(),
ysr@777 443 curr->next_top_at_mark_start(),
ysr@777 444 curr->top_at_conc_mark_count(),
ysr@777 445 curr->age_in_surv_rate_group_cond(),
ysr@777 446 curr->is_young(),
ysr@777 447 curr->is_scan_only(),
ysr@777 448 curr->is_survivor());
ysr@777 449 curr = curr->get_next_young_region();
ysr@777 450 }
ysr@777 451 }
ysr@777 452
ysr@777 453 gclog_or_tty->print_cr("");
ysr@777 454 }
ysr@777 455
ysr@777 456 void G1CollectedHeap::stop_conc_gc_threads() {
ysr@777 457 _cg1r->cg1rThread()->stop();
ysr@777 458 _czft->stop();
ysr@777 459 _cmThread->stop();
ysr@777 460 }
ysr@777 461
ysr@777 462
ysr@777 463 void G1CollectedHeap::check_ct_logs_at_safepoint() {
ysr@777 464 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set();
ysr@777 465 CardTableModRefBS* ct_bs = (CardTableModRefBS*)barrier_set();
ysr@777 466
ysr@777 467 // Count the dirty cards at the start.
ysr@777 468 CountNonCleanMemRegionClosure count1(this);
ysr@777 469 ct_bs->mod_card_iterate(&count1);
ysr@777 470 int orig_count = count1.n();
ysr@777 471
ysr@777 472 // First clear the logged cards.
ysr@777 473 ClearLoggedCardTableEntryClosure clear;
ysr@777 474 dcqs.set_closure(&clear);
ysr@777 475 dcqs.apply_closure_to_all_completed_buffers();
ysr@777 476 dcqs.iterate_closure_all_threads(false);
ysr@777 477 clear.print_histo();
ysr@777 478
ysr@777 479 // Now ensure that there's no dirty cards.
ysr@777 480 CountNonCleanMemRegionClosure count2(this);
ysr@777 481 ct_bs->mod_card_iterate(&count2);
ysr@777 482 if (count2.n() != 0) {
ysr@777 483 gclog_or_tty->print_cr("Card table has %d entries; %d originally",
ysr@777 484 count2.n(), orig_count);
ysr@777 485 }
ysr@777 486 guarantee(count2.n() == 0, "Card table should be clean.");
ysr@777 487
ysr@777 488 RedirtyLoggedCardTableEntryClosure redirty;
ysr@777 489 JavaThread::dirty_card_queue_set().set_closure(&redirty);
ysr@777 490 dcqs.apply_closure_to_all_completed_buffers();
ysr@777 491 dcqs.iterate_closure_all_threads(false);
ysr@777 492 gclog_or_tty->print_cr("Log entries = %d, dirty cards = %d.",
ysr@777 493 clear.calls(), orig_count);
ysr@777 494 guarantee(redirty.calls() == clear.calls(),
ysr@777 495 "Or else mechanism is broken.");
ysr@777 496
ysr@777 497 CountNonCleanMemRegionClosure count3(this);
ysr@777 498 ct_bs->mod_card_iterate(&count3);
ysr@777 499 if (count3.n() != orig_count) {
ysr@777 500 gclog_or_tty->print_cr("Should have restored them all: orig = %d, final = %d.",
ysr@777 501 orig_count, count3.n());
ysr@777 502 guarantee(count3.n() >= orig_count, "Should have restored them all.");
ysr@777 503 }
ysr@777 504
ysr@777 505 JavaThread::dirty_card_queue_set().set_closure(_refine_cte_cl);
ysr@777 506 }
ysr@777 507
ysr@777 508 // Private class members.
ysr@777 509
ysr@777 510 G1CollectedHeap* G1CollectedHeap::_g1h;
ysr@777 511
ysr@777 512 // Private methods.
ysr@777 513
ysr@777 514 // Finds a HeapRegion that can be used to allocate a given size of block.
ysr@777 515
ysr@777 516
ysr@777 517 HeapRegion* G1CollectedHeap::newAllocRegion_work(size_t word_size,
ysr@777 518 bool do_expand,
ysr@777 519 bool zero_filled) {
ysr@777 520 ConcurrentZFThread::note_region_alloc();
ysr@777 521 HeapRegion* res = alloc_free_region_from_lists(zero_filled);
ysr@777 522 if (res == NULL && do_expand) {
ysr@777 523 expand(word_size * HeapWordSize);
ysr@777 524 res = alloc_free_region_from_lists(zero_filled);
ysr@777 525 assert(res == NULL ||
ysr@777 526 (!res->isHumongous() &&
ysr@777 527 (!zero_filled ||
ysr@777 528 res->zero_fill_state() == HeapRegion::Allocated)),
ysr@777 529 "Alloc Regions must be zero filled (and non-H)");
ysr@777 530 }
ysr@777 531 if (res != NULL && res->is_empty()) _free_regions--;
ysr@777 532 assert(res == NULL ||
ysr@777 533 (!res->isHumongous() &&
ysr@777 534 (!zero_filled ||
ysr@777 535 res->zero_fill_state() == HeapRegion::Allocated)),
ysr@777 536 "Non-young alloc Regions must be zero filled (and non-H)");
ysr@777 537
ysr@777 538 if (G1TraceRegions) {
ysr@777 539 if (res != NULL) {
ysr@777 540 gclog_or_tty->print_cr("new alloc region %d:["PTR_FORMAT", "PTR_FORMAT"], "
ysr@777 541 "top "PTR_FORMAT,
ysr@777 542 res->hrs_index(), res->bottom(), res->end(), res->top());
ysr@777 543 }
ysr@777 544 }
ysr@777 545
ysr@777 546 return res;
ysr@777 547 }
ysr@777 548
ysr@777 549 HeapRegion* G1CollectedHeap::newAllocRegionWithExpansion(int purpose,
ysr@777 550 size_t word_size,
ysr@777 551 bool zero_filled) {
ysr@777 552 HeapRegion* alloc_region = NULL;
ysr@777 553 if (_gc_alloc_region_counts[purpose] < g1_policy()->max_regions(purpose)) {
ysr@777 554 alloc_region = newAllocRegion_work(word_size, true, zero_filled);
ysr@777 555 if (purpose == GCAllocForSurvived && alloc_region != NULL) {
ysr@777 556 _young_list->add_survivor_region(alloc_region);
ysr@777 557 }
ysr@777 558 ++_gc_alloc_region_counts[purpose];
ysr@777 559 } else {
ysr@777 560 g1_policy()->note_alloc_region_limit_reached(purpose);
ysr@777 561 }
ysr@777 562 return alloc_region;
ysr@777 563 }
ysr@777 564
ysr@777 565 // If could fit into free regions w/o expansion, try.
ysr@777 566 // Otherwise, if can expand, do so.
ysr@777 567 // Otherwise, if using ex regions might help, try with ex given back.
ysr@777 568 HeapWord* G1CollectedHeap::humongousObjAllocate(size_t word_size) {
ysr@777 569 assert(regions_accounted_for(), "Region leakage!");
ysr@777 570
ysr@777 571 // We can't allocate H regions while cleanupComplete is running, since
ysr@777 572 // some of the regions we find to be empty might not yet be added to the
ysr@777 573 // unclean list. (If we're already at a safepoint, this call is
ysr@777 574 // unnecessary, not to mention wrong.)
ysr@777 575 if (!SafepointSynchronize::is_at_safepoint())
ysr@777 576 wait_for_cleanup_complete();
ysr@777 577
ysr@777 578 size_t num_regions =
ysr@777 579 round_to(word_size, HeapRegion::GrainWords) / HeapRegion::GrainWords;
ysr@777 580
ysr@777 581 // Special case if < one region???
ysr@777 582
ysr@777 583 // Remember the ft size.
ysr@777 584 size_t x_size = expansion_regions();
ysr@777 585
ysr@777 586 HeapWord* res = NULL;
ysr@777 587 bool eliminated_allocated_from_lists = false;
ysr@777 588
ysr@777 589 // Can the allocation potentially fit in the free regions?
ysr@777 590 if (free_regions() >= num_regions) {
ysr@777 591 res = _hrs->obj_allocate(word_size);
ysr@777 592 }
ysr@777 593 if (res == NULL) {
ysr@777 594 // Try expansion.
ysr@777 595 size_t fs = _hrs->free_suffix();
ysr@777 596 if (fs + x_size >= num_regions) {
ysr@777 597 expand((num_regions - fs) * HeapRegion::GrainBytes);
ysr@777 598 res = _hrs->obj_allocate(word_size);
ysr@777 599 assert(res != NULL, "This should have worked.");
ysr@777 600 } else {
ysr@777 601 // Expansion won't help. Are there enough free regions if we get rid
ysr@777 602 // of reservations?
ysr@777 603 size_t avail = free_regions();
ysr@777 604 if (avail >= num_regions) {
ysr@777 605 res = _hrs->obj_allocate(word_size);
ysr@777 606 if (res != NULL) {
ysr@777 607 remove_allocated_regions_from_lists();
ysr@777 608 eliminated_allocated_from_lists = true;
ysr@777 609 }
ysr@777 610 }
ysr@777 611 }
ysr@777 612 }
ysr@777 613 if (res != NULL) {
ysr@777 614 // Increment by the number of regions allocated.
ysr@777 615 // FIXME: Assumes regions all of size GrainBytes.
ysr@777 616 #ifndef PRODUCT
ysr@777 617 mr_bs()->verify_clean_region(MemRegion(res, res + num_regions *
ysr@777 618 HeapRegion::GrainWords));
ysr@777 619 #endif
ysr@777 620 if (!eliminated_allocated_from_lists)
ysr@777 621 remove_allocated_regions_from_lists();
ysr@777 622 _summary_bytes_used += word_size * HeapWordSize;
ysr@777 623 _free_regions -= num_regions;
ysr@777 624 _num_humongous_regions += (int) num_regions;
ysr@777 625 }
ysr@777 626 assert(regions_accounted_for(), "Region Leakage");
ysr@777 627 return res;
ysr@777 628 }
ysr@777 629
ysr@777 630 HeapWord*
ysr@777 631 G1CollectedHeap::attempt_allocation_slow(size_t word_size,
ysr@777 632 bool permit_collection_pause) {
ysr@777 633 HeapWord* res = NULL;
ysr@777 634 HeapRegion* allocated_young_region = NULL;
ysr@777 635
ysr@777 636 assert( SafepointSynchronize::is_at_safepoint() ||
ysr@777 637 Heap_lock->owned_by_self(), "pre condition of the call" );
ysr@777 638
ysr@777 639 if (isHumongous(word_size)) {
ysr@777 640 // Allocation of a humongous object can, in a sense, complete a
ysr@777 641 // partial region, if the previous alloc was also humongous, and
ysr@777 642 // caused the test below to succeed.
ysr@777 643 if (permit_collection_pause)
ysr@777 644 do_collection_pause_if_appropriate(word_size);
ysr@777 645 res = humongousObjAllocate(word_size);
ysr@777 646 assert(_cur_alloc_region == NULL
ysr@777 647 || !_cur_alloc_region->isHumongous(),
ysr@777 648 "Prevent a regression of this bug.");
ysr@777 649
ysr@777 650 } else {
iveresov@789 651 // We may have concurrent cleanup working at the time. Wait for it
iveresov@789 652 // to complete. In the future we would probably want to make the
iveresov@789 653 // concurrent cleanup truly concurrent by decoupling it from the
iveresov@789 654 // allocation.
iveresov@789 655 if (!SafepointSynchronize::is_at_safepoint())
iveresov@789 656 wait_for_cleanup_complete();
ysr@777 657 // If we do a collection pause, this will be reset to a non-NULL
ysr@777 658 // value. If we don't, nulling here ensures that we allocate a new
ysr@777 659 // region below.
ysr@777 660 if (_cur_alloc_region != NULL) {
ysr@777 661 // We're finished with the _cur_alloc_region.
ysr@777 662 _summary_bytes_used += _cur_alloc_region->used();
ysr@777 663 _cur_alloc_region = NULL;
ysr@777 664 }
ysr@777 665 assert(_cur_alloc_region == NULL, "Invariant.");
ysr@777 666 // Completion of a heap region is perhaps a good point at which to do
ysr@777 667 // a collection pause.
ysr@777 668 if (permit_collection_pause)
ysr@777 669 do_collection_pause_if_appropriate(word_size);
ysr@777 670 // Make sure we have an allocation region available.
ysr@777 671 if (_cur_alloc_region == NULL) {
ysr@777 672 if (!SafepointSynchronize::is_at_safepoint())
ysr@777 673 wait_for_cleanup_complete();
ysr@777 674 bool next_is_young = should_set_young_locked();
ysr@777 675 // If the next region is not young, make sure it's zero-filled.
ysr@777 676 _cur_alloc_region = newAllocRegion(word_size, !next_is_young);
ysr@777 677 if (_cur_alloc_region != NULL) {
ysr@777 678 _summary_bytes_used -= _cur_alloc_region->used();
ysr@777 679 if (next_is_young) {
ysr@777 680 set_region_short_lived_locked(_cur_alloc_region);
ysr@777 681 allocated_young_region = _cur_alloc_region;
ysr@777 682 }
ysr@777 683 }
ysr@777 684 }
ysr@777 685 assert(_cur_alloc_region == NULL || !_cur_alloc_region->isHumongous(),
ysr@777 686 "Prevent a regression of this bug.");
ysr@777 687
ysr@777 688 // Now retry the allocation.
ysr@777 689 if (_cur_alloc_region != NULL) {
ysr@777 690 res = _cur_alloc_region->allocate(word_size);
ysr@777 691 }
ysr@777 692 }
ysr@777 693
ysr@777 694 // NOTE: fails frequently in PRT
ysr@777 695 assert(regions_accounted_for(), "Region leakage!");
ysr@777 696
ysr@777 697 if (res != NULL) {
ysr@777 698 if (!SafepointSynchronize::is_at_safepoint()) {
ysr@777 699 assert( permit_collection_pause, "invariant" );
ysr@777 700 assert( Heap_lock->owned_by_self(), "invariant" );
ysr@777 701 Heap_lock->unlock();
ysr@777 702 }
ysr@777 703
ysr@777 704 if (allocated_young_region != NULL) {
ysr@777 705 HeapRegion* hr = allocated_young_region;
ysr@777 706 HeapWord* bottom = hr->bottom();
ysr@777 707 HeapWord* end = hr->end();
ysr@777 708 MemRegion mr(bottom, end);
ysr@777 709 ((CardTableModRefBS*)_g1h->barrier_set())->dirty(mr);
ysr@777 710 }
ysr@777 711 }
ysr@777 712
ysr@777 713 assert( SafepointSynchronize::is_at_safepoint() ||
ysr@777 714 (res == NULL && Heap_lock->owned_by_self()) ||
ysr@777 715 (res != NULL && !Heap_lock->owned_by_self()),
ysr@777 716 "post condition of the call" );
ysr@777 717
ysr@777 718 return res;
ysr@777 719 }
ysr@777 720
ysr@777 721 HeapWord*
ysr@777 722 G1CollectedHeap::mem_allocate(size_t word_size,
ysr@777 723 bool is_noref,
ysr@777 724 bool is_tlab,
ysr@777 725 bool* gc_overhead_limit_was_exceeded) {
ysr@777 726 debug_only(check_for_valid_allocation_state());
ysr@777 727 assert(no_gc_in_progress(), "Allocation during gc not allowed");
ysr@777 728 HeapWord* result = NULL;
ysr@777 729
ysr@777 730 // Loop until the allocation is satisified,
ysr@777 731 // or unsatisfied after GC.
ysr@777 732 for (int try_count = 1; /* return or throw */; try_count += 1) {
ysr@777 733 int gc_count_before;
ysr@777 734 {
ysr@777 735 Heap_lock->lock();
ysr@777 736 result = attempt_allocation(word_size);
ysr@777 737 if (result != NULL) {
ysr@777 738 // attempt_allocation should have unlocked the heap lock
ysr@777 739 assert(is_in(result), "result not in heap");
ysr@777 740 return result;
ysr@777 741 }
ysr@777 742 // Read the gc count while the heap lock is held.
ysr@777 743 gc_count_before = SharedHeap::heap()->total_collections();
ysr@777 744 Heap_lock->unlock();
ysr@777 745 }
ysr@777 746
ysr@777 747 // Create the garbage collection operation...
ysr@777 748 VM_G1CollectForAllocation op(word_size,
ysr@777 749 gc_count_before);
ysr@777 750
ysr@777 751 // ...and get the VM thread to execute it.
ysr@777 752 VMThread::execute(&op);
ysr@777 753 if (op.prologue_succeeded()) {
ysr@777 754 result = op.result();
ysr@777 755 assert(result == NULL || is_in(result), "result not in heap");
ysr@777 756 return result;
ysr@777 757 }
ysr@777 758
ysr@777 759 // Give a warning if we seem to be looping forever.
ysr@777 760 if ((QueuedAllocationWarningCount > 0) &&
ysr@777 761 (try_count % QueuedAllocationWarningCount == 0)) {
ysr@777 762 warning("G1CollectedHeap::mem_allocate_work retries %d times",
ysr@777 763 try_count);
ysr@777 764 }
ysr@777 765 }
ysr@777 766 }
ysr@777 767
ysr@777 768 void G1CollectedHeap::abandon_cur_alloc_region() {
ysr@777 769 if (_cur_alloc_region != NULL) {
ysr@777 770 // We're finished with the _cur_alloc_region.
ysr@777 771 if (_cur_alloc_region->is_empty()) {
ysr@777 772 _free_regions++;
ysr@777 773 free_region(_cur_alloc_region);
ysr@777 774 } else {
ysr@777 775 _summary_bytes_used += _cur_alloc_region->used();
ysr@777 776 }
ysr@777 777 _cur_alloc_region = NULL;
ysr@777 778 }
ysr@777 779 }
ysr@777 780
ysr@777 781 class PostMCRemSetClearClosure: public HeapRegionClosure {
ysr@777 782 ModRefBarrierSet* _mr_bs;
ysr@777 783 public:
ysr@777 784 PostMCRemSetClearClosure(ModRefBarrierSet* mr_bs) : _mr_bs(mr_bs) {}
ysr@777 785 bool doHeapRegion(HeapRegion* r) {
ysr@777 786 r->reset_gc_time_stamp();
ysr@777 787 if (r->continuesHumongous())
ysr@777 788 return false;
ysr@777 789 HeapRegionRemSet* hrrs = r->rem_set();
ysr@777 790 if (hrrs != NULL) hrrs->clear();
ysr@777 791 // You might think here that we could clear just the cards
ysr@777 792 // corresponding to the used region. But no: if we leave a dirty card
ysr@777 793 // in a region we might allocate into, then it would prevent that card
ysr@777 794 // from being enqueued, and cause it to be missed.
ysr@777 795 // Re: the performance cost: we shouldn't be doing full GC anyway!
ysr@777 796 _mr_bs->clear(MemRegion(r->bottom(), r->end()));
ysr@777 797 return false;
ysr@777 798 }
ysr@777 799 };
ysr@777 800
ysr@777 801
ysr@777 802 class PostMCRemSetInvalidateClosure: public HeapRegionClosure {
ysr@777 803 ModRefBarrierSet* _mr_bs;
ysr@777 804 public:
ysr@777 805 PostMCRemSetInvalidateClosure(ModRefBarrierSet* mr_bs) : _mr_bs(mr_bs) {}
ysr@777 806 bool doHeapRegion(HeapRegion* r) {
ysr@777 807 if (r->continuesHumongous()) return false;
ysr@777 808 if (r->used_region().word_size() != 0) {
ysr@777 809 _mr_bs->invalidate(r->used_region(), true /*whole heap*/);
ysr@777 810 }
ysr@777 811 return false;
ysr@777 812 }
ysr@777 813 };
ysr@777 814
ysr@777 815 void G1CollectedHeap::do_collection(bool full, bool clear_all_soft_refs,
ysr@777 816 size_t word_size) {
ysr@777 817 ResourceMark rm;
ysr@777 818
ysr@777 819 if (full && DisableExplicitGC) {
ysr@777 820 gclog_or_tty->print("\n\n\nDisabling Explicit GC\n\n\n");
ysr@777 821 return;
ysr@777 822 }
ysr@777 823
ysr@777 824 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
ysr@777 825 assert(Thread::current() == VMThread::vm_thread(), "should be in vm thread");
ysr@777 826
ysr@777 827 if (GC_locker::is_active()) {
ysr@777 828 return; // GC is disabled (e.g. JNI GetXXXCritical operation)
ysr@777 829 }
ysr@777 830
ysr@777 831 {
ysr@777 832 IsGCActiveMark x;
ysr@777 833
ysr@777 834 // Timing
ysr@777 835 gclog_or_tty->date_stamp(PrintGC && PrintGCDateStamps);
ysr@777 836 TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty);
ysr@777 837 TraceTime t(full ? "Full GC (System.gc())" : "Full GC", PrintGC, true, gclog_or_tty);
ysr@777 838
ysr@777 839 double start = os::elapsedTime();
ysr@777 840 GCOverheadReporter::recordSTWStart(start);
ysr@777 841 g1_policy()->record_full_collection_start();
ysr@777 842
ysr@777 843 gc_prologue(true);
ysr@777 844 increment_total_collections();
ysr@777 845
ysr@777 846 size_t g1h_prev_used = used();
ysr@777 847 assert(used() == recalculate_used(), "Should be equal");
ysr@777 848
ysr@777 849 if (VerifyBeforeGC && total_collections() >= VerifyGCStartAt) {
ysr@777 850 HandleMark hm; // Discard invalid handles created during verification
ysr@777 851 prepare_for_verify();
ysr@777 852 gclog_or_tty->print(" VerifyBeforeGC:");
ysr@777 853 Universe::verify(true);
ysr@777 854 }
ysr@777 855 assert(regions_accounted_for(), "Region leakage!");
ysr@777 856
ysr@777 857 COMPILER2_PRESENT(DerivedPointerTable::clear());
ysr@777 858
ysr@777 859 // We want to discover references, but not process them yet.
ysr@777 860 // This mode is disabled in
ysr@777 861 // instanceRefKlass::process_discovered_references if the
ysr@777 862 // generation does some collection work, or
ysr@777 863 // instanceRefKlass::enqueue_discovered_references if the
ysr@777 864 // generation returns without doing any work.
ysr@777 865 ref_processor()->disable_discovery();
ysr@777 866 ref_processor()->abandon_partial_discovery();
ysr@777 867 ref_processor()->verify_no_references_recorded();
ysr@777 868
ysr@777 869 // Abandon current iterations of concurrent marking and concurrent
ysr@777 870 // refinement, if any are in progress.
ysr@777 871 concurrent_mark()->abort();
ysr@777 872
ysr@777 873 // Make sure we'll choose a new allocation region afterwards.
ysr@777 874 abandon_cur_alloc_region();
ysr@777 875 assert(_cur_alloc_region == NULL, "Invariant.");
ysr@777 876 g1_rem_set()->as_HRInto_G1RemSet()->cleanupHRRS();
ysr@777 877 tear_down_region_lists();
ysr@777 878 set_used_regions_to_need_zero_fill();
ysr@777 879 if (g1_policy()->in_young_gc_mode()) {
ysr@777 880 empty_young_list();
ysr@777 881 g1_policy()->set_full_young_gcs(true);
ysr@777 882 }
ysr@777 883
ysr@777 884 // Temporarily make reference _discovery_ single threaded (non-MT).
ysr@777 885 ReferenceProcessorMTMutator rp_disc_ser(ref_processor(), false);
ysr@777 886
ysr@777 887 // Temporarily make refs discovery atomic
ysr@777 888 ReferenceProcessorAtomicMutator rp_disc_atomic(ref_processor(), true);
ysr@777 889
ysr@777 890 // Temporarily clear _is_alive_non_header
ysr@777 891 ReferenceProcessorIsAliveMutator rp_is_alive_null(ref_processor(), NULL);
ysr@777 892
ysr@777 893 ref_processor()->enable_discovery();
ysr@777 894
ysr@777 895 // Do collection work
ysr@777 896 {
ysr@777 897 HandleMark hm; // Discard invalid handles created during gc
ysr@777 898 G1MarkSweep::invoke_at_safepoint(ref_processor(), clear_all_soft_refs);
ysr@777 899 }
ysr@777 900 // Because freeing humongous regions may have added some unclean
ysr@777 901 // regions, it is necessary to tear down again before rebuilding.
ysr@777 902 tear_down_region_lists();
ysr@777 903 rebuild_region_lists();
ysr@777 904
ysr@777 905 _summary_bytes_used = recalculate_used();
ysr@777 906
ysr@777 907 ref_processor()->enqueue_discovered_references();
ysr@777 908
ysr@777 909 COMPILER2_PRESENT(DerivedPointerTable::update_pointers());
ysr@777 910
ysr@777 911 if (VerifyAfterGC && total_collections() >= VerifyGCStartAt) {
ysr@777 912 HandleMark hm; // Discard invalid handles created during verification
ysr@777 913 gclog_or_tty->print(" VerifyAfterGC:");
ysr@777 914 Universe::verify(false);
ysr@777 915 }
ysr@777 916 NOT_PRODUCT(ref_processor()->verify_no_references_recorded());
ysr@777 917
ysr@777 918 reset_gc_time_stamp();
ysr@777 919 // Since everything potentially moved, we will clear all remembered
ysr@777 920 // sets, and clear all cards. Later we will also cards in the used
ysr@777 921 // portion of the heap after the resizing (which could be a shrinking.)
ysr@777 922 // We will also reset the GC time stamps of the regions.
ysr@777 923 PostMCRemSetClearClosure rs_clear(mr_bs());
ysr@777 924 heap_region_iterate(&rs_clear);
ysr@777 925
ysr@777 926 // Resize the heap if necessary.
ysr@777 927 resize_if_necessary_after_full_collection(full ? 0 : word_size);
ysr@777 928
ysr@777 929 // Since everything potentially moved, we will clear all remembered
ysr@777 930 // sets, but also dirty all cards corresponding to used regions.
ysr@777 931 PostMCRemSetInvalidateClosure rs_invalidate(mr_bs());
ysr@777 932 heap_region_iterate(&rs_invalidate);
ysr@777 933 if (_cg1r->use_cache()) {
ysr@777 934 _cg1r->clear_and_record_card_counts();
ysr@777 935 _cg1r->clear_hot_cache();
ysr@777 936 }
ysr@777 937
ysr@777 938 if (PrintGC) {
ysr@777 939 print_size_transition(gclog_or_tty, g1h_prev_used, used(), capacity());
ysr@777 940 }
ysr@777 941
ysr@777 942 if (true) { // FIXME
ysr@777 943 // Ask the permanent generation to adjust size for full collections
ysr@777 944 perm()->compute_new_size();
ysr@777 945 }
ysr@777 946
ysr@777 947 double end = os::elapsedTime();
ysr@777 948 GCOverheadReporter::recordSTWEnd(end);
ysr@777 949 g1_policy()->record_full_collection_end();
ysr@777 950
ysr@777 951 gc_epilogue(true);
ysr@777 952
ysr@777 953 // Abandon concurrent refinement. This must happen last: in the
ysr@777 954 // dirty-card logging system, some cards may be dirty by weak-ref
ysr@777 955 // processing, and may be enqueued. But the whole card table is
ysr@777 956 // dirtied, so this should abandon those logs, and set "do_traversal"
ysr@777 957 // to true.
ysr@777 958 concurrent_g1_refine()->set_pya_restart();
ysr@777 959
ysr@777 960 assert(regions_accounted_for(), "Region leakage!");
ysr@777 961 }
ysr@777 962
ysr@777 963 if (g1_policy()->in_young_gc_mode()) {
ysr@777 964 _young_list->reset_sampled_info();
ysr@777 965 assert( check_young_list_empty(false, false),
ysr@777 966 "young list should be empty at this point");
ysr@777 967 }
ysr@777 968 }
ysr@777 969
ysr@777 970 void G1CollectedHeap::do_full_collection(bool clear_all_soft_refs) {
ysr@777 971 do_collection(true, clear_all_soft_refs, 0);
ysr@777 972 }
ysr@777 973
ysr@777 974 // This code is mostly copied from TenuredGeneration.
ysr@777 975 void
ysr@777 976 G1CollectedHeap::
ysr@777 977 resize_if_necessary_after_full_collection(size_t word_size) {
ysr@777 978 assert(MinHeapFreeRatio <= MaxHeapFreeRatio, "sanity check");
ysr@777 979
ysr@777 980 // Include the current allocation, if any, and bytes that will be
ysr@777 981 // pre-allocated to support collections, as "used".
ysr@777 982 const size_t used_after_gc = used();
ysr@777 983 const size_t capacity_after_gc = capacity();
ysr@777 984 const size_t free_after_gc = capacity_after_gc - used_after_gc;
ysr@777 985
ysr@777 986 // We don't have floating point command-line arguments
ysr@777 987 const double minimum_free_percentage = (double) MinHeapFreeRatio / 100;
ysr@777 988 const double maximum_used_percentage = 1.0 - minimum_free_percentage;
ysr@777 989 const double maximum_free_percentage = (double) MaxHeapFreeRatio / 100;
ysr@777 990 const double minimum_used_percentage = 1.0 - maximum_free_percentage;
ysr@777 991
ysr@777 992 size_t minimum_desired_capacity = (size_t) (used_after_gc / maximum_used_percentage);
ysr@777 993 size_t maximum_desired_capacity = (size_t) (used_after_gc / minimum_used_percentage);
ysr@777 994
ysr@777 995 // Don't shrink less than the initial size.
ysr@777 996 minimum_desired_capacity =
ysr@777 997 MAX2(minimum_desired_capacity,
ysr@777 998 collector_policy()->initial_heap_byte_size());
ysr@777 999 maximum_desired_capacity =
ysr@777 1000 MAX2(maximum_desired_capacity,
ysr@777 1001 collector_policy()->initial_heap_byte_size());
ysr@777 1002
ysr@777 1003 // We are failing here because minimum_desired_capacity is
ysr@777 1004 assert(used_after_gc <= minimum_desired_capacity, "sanity check");
ysr@777 1005 assert(minimum_desired_capacity <= maximum_desired_capacity, "sanity check");
ysr@777 1006
ysr@777 1007 if (PrintGC && Verbose) {
ysr@777 1008 const double free_percentage = ((double)free_after_gc) / capacity();
ysr@777 1009 gclog_or_tty->print_cr("Computing new size after full GC ");
ysr@777 1010 gclog_or_tty->print_cr(" "
ysr@777 1011 " minimum_free_percentage: %6.2f",
ysr@777 1012 minimum_free_percentage);
ysr@777 1013 gclog_or_tty->print_cr(" "
ysr@777 1014 " maximum_free_percentage: %6.2f",
ysr@777 1015 maximum_free_percentage);
ysr@777 1016 gclog_or_tty->print_cr(" "
ysr@777 1017 " capacity: %6.1fK"
ysr@777 1018 " minimum_desired_capacity: %6.1fK"
ysr@777 1019 " maximum_desired_capacity: %6.1fK",
ysr@777 1020 capacity() / (double) K,
ysr@777 1021 minimum_desired_capacity / (double) K,
ysr@777 1022 maximum_desired_capacity / (double) K);
ysr@777 1023 gclog_or_tty->print_cr(" "
ysr@777 1024 " free_after_gc : %6.1fK"
ysr@777 1025 " used_after_gc : %6.1fK",
ysr@777 1026 free_after_gc / (double) K,
ysr@777 1027 used_after_gc / (double) K);
ysr@777 1028 gclog_or_tty->print_cr(" "
ysr@777 1029 " free_percentage: %6.2f",
ysr@777 1030 free_percentage);
ysr@777 1031 }
ysr@777 1032 if (capacity() < minimum_desired_capacity) {
ysr@777 1033 // Don't expand unless it's significant
ysr@777 1034 size_t expand_bytes = minimum_desired_capacity - capacity_after_gc;
ysr@777 1035 expand(expand_bytes);
ysr@777 1036 if (PrintGC && Verbose) {
ysr@777 1037 gclog_or_tty->print_cr(" expanding:"
ysr@777 1038 " minimum_desired_capacity: %6.1fK"
ysr@777 1039 " expand_bytes: %6.1fK",
ysr@777 1040 minimum_desired_capacity / (double) K,
ysr@777 1041 expand_bytes / (double) K);
ysr@777 1042 }
ysr@777 1043
ysr@777 1044 // No expansion, now see if we want to shrink
ysr@777 1045 } else if (capacity() > maximum_desired_capacity) {
ysr@777 1046 // Capacity too large, compute shrinking size
ysr@777 1047 size_t shrink_bytes = capacity_after_gc - maximum_desired_capacity;
ysr@777 1048 shrink(shrink_bytes);
ysr@777 1049 if (PrintGC && Verbose) {
ysr@777 1050 gclog_or_tty->print_cr(" "
ysr@777 1051 " shrinking:"
ysr@777 1052 " initSize: %.1fK"
ysr@777 1053 " maximum_desired_capacity: %.1fK",
ysr@777 1054 collector_policy()->initial_heap_byte_size() / (double) K,
ysr@777 1055 maximum_desired_capacity / (double) K);
ysr@777 1056 gclog_or_tty->print_cr(" "
ysr@777 1057 " shrink_bytes: %.1fK",
ysr@777 1058 shrink_bytes / (double) K);
ysr@777 1059 }
ysr@777 1060 }
ysr@777 1061 }
ysr@777 1062
ysr@777 1063
ysr@777 1064 HeapWord*
ysr@777 1065 G1CollectedHeap::satisfy_failed_allocation(size_t word_size) {
ysr@777 1066 HeapWord* result = NULL;
ysr@777 1067
ysr@777 1068 // In a G1 heap, we're supposed to keep allocation from failing by
ysr@777 1069 // incremental pauses. Therefore, at least for now, we'll favor
ysr@777 1070 // expansion over collection. (This might change in the future if we can
ysr@777 1071 // do something smarter than full collection to satisfy a failed alloc.)
ysr@777 1072
ysr@777 1073 result = expand_and_allocate(word_size);
ysr@777 1074 if (result != NULL) {
ysr@777 1075 assert(is_in(result), "result not in heap");
ysr@777 1076 return result;
ysr@777 1077 }
ysr@777 1078
ysr@777 1079 // OK, I guess we have to try collection.
ysr@777 1080
ysr@777 1081 do_collection(false, false, word_size);
ysr@777 1082
ysr@777 1083 result = attempt_allocation(word_size, /*permit_collection_pause*/false);
ysr@777 1084
ysr@777 1085 if (result != NULL) {
ysr@777 1086 assert(is_in(result), "result not in heap");
ysr@777 1087 return result;
ysr@777 1088 }
ysr@777 1089
ysr@777 1090 // Try collecting soft references.
ysr@777 1091 do_collection(false, true, word_size);
ysr@777 1092 result = attempt_allocation(word_size, /*permit_collection_pause*/false);
ysr@777 1093 if (result != NULL) {
ysr@777 1094 assert(is_in(result), "result not in heap");
ysr@777 1095 return result;
ysr@777 1096 }
ysr@777 1097
ysr@777 1098 // What else? We might try synchronous finalization later. If the total
ysr@777 1099 // space available is large enough for the allocation, then a more
ysr@777 1100 // complete compaction phase than we've tried so far might be
ysr@777 1101 // appropriate.
ysr@777 1102 return NULL;
ysr@777 1103 }
ysr@777 1104
ysr@777 1105 // Attempting to expand the heap sufficiently
ysr@777 1106 // to support an allocation of the given "word_size". If
ysr@777 1107 // successful, perform the allocation and return the address of the
ysr@777 1108 // allocated block, or else "NULL".
ysr@777 1109
ysr@777 1110 HeapWord* G1CollectedHeap::expand_and_allocate(size_t word_size) {
ysr@777 1111 size_t expand_bytes = word_size * HeapWordSize;
ysr@777 1112 if (expand_bytes < MinHeapDeltaBytes) {
ysr@777 1113 expand_bytes = MinHeapDeltaBytes;
ysr@777 1114 }
ysr@777 1115 expand(expand_bytes);
ysr@777 1116 assert(regions_accounted_for(), "Region leakage!");
ysr@777 1117 HeapWord* result = attempt_allocation(word_size, false /* permit_collection_pause */);
ysr@777 1118 return result;
ysr@777 1119 }
ysr@777 1120
ysr@777 1121 size_t G1CollectedHeap::free_region_if_totally_empty(HeapRegion* hr) {
ysr@777 1122 size_t pre_used = 0;
ysr@777 1123 size_t cleared_h_regions = 0;
ysr@777 1124 size_t freed_regions = 0;
ysr@777 1125 UncleanRegionList local_list;
ysr@777 1126 free_region_if_totally_empty_work(hr, pre_used, cleared_h_regions,
ysr@777 1127 freed_regions, &local_list);
ysr@777 1128
ysr@777 1129 finish_free_region_work(pre_used, cleared_h_regions, freed_regions,
ysr@777 1130 &local_list);
ysr@777 1131 return pre_used;
ysr@777 1132 }
ysr@777 1133
ysr@777 1134 void
ysr@777 1135 G1CollectedHeap::free_region_if_totally_empty_work(HeapRegion* hr,
ysr@777 1136 size_t& pre_used,
ysr@777 1137 size_t& cleared_h,
ysr@777 1138 size_t& freed_regions,
ysr@777 1139 UncleanRegionList* list,
ysr@777 1140 bool par) {
ysr@777 1141 assert(!hr->continuesHumongous(), "should have filtered these out");
ysr@777 1142 size_t res = 0;
ysr@777 1143 if (!hr->popular() && hr->used() > 0 && hr->garbage_bytes() == hr->used()) {
ysr@777 1144 if (!hr->is_young()) {
ysr@777 1145 if (G1PolicyVerbose > 0)
ysr@777 1146 gclog_or_tty->print_cr("Freeing empty region "PTR_FORMAT "(" SIZE_FORMAT " bytes)"
ysr@777 1147 " during cleanup", hr, hr->used());
ysr@777 1148 free_region_work(hr, pre_used, cleared_h, freed_regions, list, par);
ysr@777 1149 }
ysr@777 1150 }
ysr@777 1151 }
ysr@777 1152
ysr@777 1153 // FIXME: both this and shrink could probably be more efficient by
ysr@777 1154 // doing one "VirtualSpace::expand_by" call rather than several.
ysr@777 1155 void G1CollectedHeap::expand(size_t expand_bytes) {
ysr@777 1156 size_t old_mem_size = _g1_storage.committed_size();
ysr@777 1157 // We expand by a minimum of 1K.
ysr@777 1158 expand_bytes = MAX2(expand_bytes, (size_t)K);
ysr@777 1159 size_t aligned_expand_bytes =
ysr@777 1160 ReservedSpace::page_align_size_up(expand_bytes);
ysr@777 1161 aligned_expand_bytes = align_size_up(aligned_expand_bytes,
ysr@777 1162 HeapRegion::GrainBytes);
ysr@777 1163 expand_bytes = aligned_expand_bytes;
ysr@777 1164 while (expand_bytes > 0) {
ysr@777 1165 HeapWord* base = (HeapWord*)_g1_storage.high();
ysr@777 1166 // Commit more storage.
ysr@777 1167 bool successful = _g1_storage.expand_by(HeapRegion::GrainBytes);
ysr@777 1168 if (!successful) {
ysr@777 1169 expand_bytes = 0;
ysr@777 1170 } else {
ysr@777 1171 expand_bytes -= HeapRegion::GrainBytes;
ysr@777 1172 // Expand the committed region.
ysr@777 1173 HeapWord* high = (HeapWord*) _g1_storage.high();
ysr@777 1174 _g1_committed.set_end(high);
ysr@777 1175 // Create a new HeapRegion.
ysr@777 1176 MemRegion mr(base, high);
ysr@777 1177 bool is_zeroed = !_g1_max_committed.contains(base);
ysr@777 1178 HeapRegion* hr = new HeapRegion(_bot_shared, mr, is_zeroed);
ysr@777 1179
ysr@777 1180 // Now update max_committed if necessary.
ysr@777 1181 _g1_max_committed.set_end(MAX2(_g1_max_committed.end(), high));
ysr@777 1182
ysr@777 1183 // Add it to the HeapRegionSeq.
ysr@777 1184 _hrs->insert(hr);
ysr@777 1185 // Set the zero-fill state, according to whether it's already
ysr@777 1186 // zeroed.
ysr@777 1187 {
ysr@777 1188 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 1189 if (is_zeroed) {
ysr@777 1190 hr->set_zero_fill_complete();
ysr@777 1191 put_free_region_on_list_locked(hr);
ysr@777 1192 } else {
ysr@777 1193 hr->set_zero_fill_needed();
ysr@777 1194 put_region_on_unclean_list_locked(hr);
ysr@777 1195 }
ysr@777 1196 }
ysr@777 1197 _free_regions++;
ysr@777 1198 // And we used up an expansion region to create it.
ysr@777 1199 _expansion_regions--;
ysr@777 1200 // Tell the cardtable about it.
ysr@777 1201 Universe::heap()->barrier_set()->resize_covered_region(_g1_committed);
ysr@777 1202 // And the offset table as well.
ysr@777 1203 _bot_shared->resize(_g1_committed.word_size());
ysr@777 1204 }
ysr@777 1205 }
ysr@777 1206 if (Verbose && PrintGC) {
ysr@777 1207 size_t new_mem_size = _g1_storage.committed_size();
ysr@777 1208 gclog_or_tty->print_cr("Expanding garbage-first heap from %ldK by %ldK to %ldK",
ysr@777 1209 old_mem_size/K, aligned_expand_bytes/K,
ysr@777 1210 new_mem_size/K);
ysr@777 1211 }
ysr@777 1212 }
ysr@777 1213
ysr@777 1214 void G1CollectedHeap::shrink_helper(size_t shrink_bytes)
ysr@777 1215 {
ysr@777 1216 size_t old_mem_size = _g1_storage.committed_size();
ysr@777 1217 size_t aligned_shrink_bytes =
ysr@777 1218 ReservedSpace::page_align_size_down(shrink_bytes);
ysr@777 1219 aligned_shrink_bytes = align_size_down(aligned_shrink_bytes,
ysr@777 1220 HeapRegion::GrainBytes);
ysr@777 1221 size_t num_regions_deleted = 0;
ysr@777 1222 MemRegion mr = _hrs->shrink_by(aligned_shrink_bytes, num_regions_deleted);
ysr@777 1223
ysr@777 1224 assert(mr.end() == (HeapWord*)_g1_storage.high(), "Bad shrink!");
ysr@777 1225 if (mr.byte_size() > 0)
ysr@777 1226 _g1_storage.shrink_by(mr.byte_size());
ysr@777 1227 assert(mr.start() == (HeapWord*)_g1_storage.high(), "Bad shrink!");
ysr@777 1228
ysr@777 1229 _g1_committed.set_end(mr.start());
ysr@777 1230 _free_regions -= num_regions_deleted;
ysr@777 1231 _expansion_regions += num_regions_deleted;
ysr@777 1232
ysr@777 1233 // Tell the cardtable about it.
ysr@777 1234 Universe::heap()->barrier_set()->resize_covered_region(_g1_committed);
ysr@777 1235
ysr@777 1236 // And the offset table as well.
ysr@777 1237 _bot_shared->resize(_g1_committed.word_size());
ysr@777 1238
ysr@777 1239 HeapRegionRemSet::shrink_heap(n_regions());
ysr@777 1240
ysr@777 1241 if (Verbose && PrintGC) {
ysr@777 1242 size_t new_mem_size = _g1_storage.committed_size();
ysr@777 1243 gclog_or_tty->print_cr("Shrinking garbage-first heap from %ldK by %ldK to %ldK",
ysr@777 1244 old_mem_size/K, aligned_shrink_bytes/K,
ysr@777 1245 new_mem_size/K);
ysr@777 1246 }
ysr@777 1247 }
ysr@777 1248
ysr@777 1249 void G1CollectedHeap::shrink(size_t shrink_bytes) {
ysr@777 1250 release_gc_alloc_regions();
ysr@777 1251 tear_down_region_lists(); // We will rebuild them in a moment.
ysr@777 1252 shrink_helper(shrink_bytes);
ysr@777 1253 rebuild_region_lists();
ysr@777 1254 }
ysr@777 1255
ysr@777 1256 // Public methods.
ysr@777 1257
ysr@777 1258 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
ysr@777 1259 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
ysr@777 1260 #endif // _MSC_VER
ysr@777 1261
ysr@777 1262
ysr@777 1263 G1CollectedHeap::G1CollectedHeap(G1CollectorPolicy* policy_) :
ysr@777 1264 SharedHeap(policy_),
ysr@777 1265 _g1_policy(policy_),
ysr@777 1266 _ref_processor(NULL),
ysr@777 1267 _process_strong_tasks(new SubTasksDone(G1H_PS_NumElements)),
ysr@777 1268 _bot_shared(NULL),
ysr@777 1269 _par_alloc_during_gc_lock(Mutex::leaf, "par alloc during GC lock"),
ysr@777 1270 _objs_with_preserved_marks(NULL), _preserved_marks_of_objs(NULL),
ysr@777 1271 _evac_failure_scan_stack(NULL) ,
ysr@777 1272 _mark_in_progress(false),
ysr@777 1273 _cg1r(NULL), _czft(NULL), _summary_bytes_used(0),
ysr@777 1274 _cur_alloc_region(NULL),
ysr@777 1275 _refine_cte_cl(NULL),
ysr@777 1276 _free_region_list(NULL), _free_region_list_size(0),
ysr@777 1277 _free_regions(0),
ysr@777 1278 _popular_object_boundary(NULL),
ysr@777 1279 _cur_pop_hr_index(0),
ysr@777 1280 _popular_regions_to_be_evacuated(NULL),
ysr@777 1281 _pop_obj_rc_at_copy(),
ysr@777 1282 _full_collection(false),
ysr@777 1283 _unclean_region_list(),
ysr@777 1284 _unclean_regions_coming(false),
ysr@777 1285 _young_list(new YoungList(this)),
ysr@777 1286 _gc_time_stamp(0),
ysr@777 1287 _surviving_young_words(NULL)
ysr@777 1288 {
ysr@777 1289 _g1h = this; // To catch bugs.
ysr@777 1290 if (_process_strong_tasks == NULL || !_process_strong_tasks->valid()) {
ysr@777 1291 vm_exit_during_initialization("Failed necessary allocation.");
ysr@777 1292 }
ysr@777 1293 int n_queues = MAX2((int)ParallelGCThreads, 1);
ysr@777 1294 _task_queues = new RefToScanQueueSet(n_queues);
ysr@777 1295
ysr@777 1296 int n_rem_sets = HeapRegionRemSet::num_par_rem_sets();
ysr@777 1297 assert(n_rem_sets > 0, "Invariant.");
ysr@777 1298
ysr@777 1299 HeapRegionRemSetIterator** iter_arr =
ysr@777 1300 NEW_C_HEAP_ARRAY(HeapRegionRemSetIterator*, n_queues);
ysr@777 1301 for (int i = 0; i < n_queues; i++) {
ysr@777 1302 iter_arr[i] = new HeapRegionRemSetIterator();
ysr@777 1303 }
ysr@777 1304 _rem_set_iterator = iter_arr;
ysr@777 1305
ysr@777 1306 for (int i = 0; i < n_queues; i++) {
ysr@777 1307 RefToScanQueue* q = new RefToScanQueue();
ysr@777 1308 q->initialize();
ysr@777 1309 _task_queues->register_queue(i, q);
ysr@777 1310 }
ysr@777 1311
ysr@777 1312 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) {
ysr@777 1313 _gc_alloc_regions[ap] = NULL;
ysr@777 1314 _gc_alloc_region_counts[ap] = 0;
ysr@777 1315 }
ysr@777 1316 guarantee(_task_queues != NULL, "task_queues allocation failure.");
ysr@777 1317 }
ysr@777 1318
ysr@777 1319 jint G1CollectedHeap::initialize() {
ysr@777 1320 os::enable_vtime();
ysr@777 1321
ysr@777 1322 // Necessary to satisfy locking discipline assertions.
ysr@777 1323
ysr@777 1324 MutexLocker x(Heap_lock);
ysr@777 1325
ysr@777 1326 // While there are no constraints in the GC code that HeapWordSize
ysr@777 1327 // be any particular value, there are multiple other areas in the
ysr@777 1328 // system which believe this to be true (e.g. oop->object_size in some
ysr@777 1329 // cases incorrectly returns the size in wordSize units rather than
ysr@777 1330 // HeapWordSize).
ysr@777 1331 guarantee(HeapWordSize == wordSize, "HeapWordSize must equal wordSize");
ysr@777 1332
ysr@777 1333 size_t init_byte_size = collector_policy()->initial_heap_byte_size();
ysr@777 1334 size_t max_byte_size = collector_policy()->max_heap_byte_size();
ysr@777 1335
ysr@777 1336 // Ensure that the sizes are properly aligned.
ysr@777 1337 Universe::check_alignment(init_byte_size, HeapRegion::GrainBytes, "g1 heap");
ysr@777 1338 Universe::check_alignment(max_byte_size, HeapRegion::GrainBytes, "g1 heap");
ysr@777 1339
ysr@777 1340 // We allocate this in any case, but only do no work if the command line
ysr@777 1341 // param is off.
ysr@777 1342 _cg1r = new ConcurrentG1Refine();
ysr@777 1343
ysr@777 1344 // Reserve the maximum.
ysr@777 1345 PermanentGenerationSpec* pgs = collector_policy()->permanent_generation();
ysr@777 1346 // Includes the perm-gen.
ysr@777 1347 ReservedSpace heap_rs(max_byte_size + pgs->max_size(),
ysr@777 1348 HeapRegion::GrainBytes,
ysr@777 1349 false /*ism*/);
ysr@777 1350
ysr@777 1351 if (!heap_rs.is_reserved()) {
ysr@777 1352 vm_exit_during_initialization("Could not reserve enough space for object heap");
ysr@777 1353 return JNI_ENOMEM;
ysr@777 1354 }
ysr@777 1355
ysr@777 1356 // It is important to do this in a way such that concurrent readers can't
ysr@777 1357 // temporarily think somethings in the heap. (I've actually seen this
ysr@777 1358 // happen in asserts: DLD.)
ysr@777 1359 _reserved.set_word_size(0);
ysr@777 1360 _reserved.set_start((HeapWord*)heap_rs.base());
ysr@777 1361 _reserved.set_end((HeapWord*)(heap_rs.base() + heap_rs.size()));
ysr@777 1362
ysr@777 1363 _expansion_regions = max_byte_size/HeapRegion::GrainBytes;
ysr@777 1364
ysr@777 1365 _num_humongous_regions = 0;
ysr@777 1366
ysr@777 1367 // Create the gen rem set (and barrier set) for the entire reserved region.
ysr@777 1368 _rem_set = collector_policy()->create_rem_set(_reserved, 2);
ysr@777 1369 set_barrier_set(rem_set()->bs());
ysr@777 1370 if (barrier_set()->is_a(BarrierSet::ModRef)) {
ysr@777 1371 _mr_bs = (ModRefBarrierSet*)_barrier_set;
ysr@777 1372 } else {
ysr@777 1373 vm_exit_during_initialization("G1 requires a mod ref bs.");
ysr@777 1374 return JNI_ENOMEM;
ysr@777 1375 }
ysr@777 1376
ysr@777 1377 // Also create a G1 rem set.
ysr@777 1378 if (G1UseHRIntoRS) {
ysr@777 1379 if (mr_bs()->is_a(BarrierSet::CardTableModRef)) {
ysr@777 1380 _g1_rem_set = new HRInto_G1RemSet(this, (CardTableModRefBS*)mr_bs());
ysr@777 1381 } else {
ysr@777 1382 vm_exit_during_initialization("G1 requires a cardtable mod ref bs.");
ysr@777 1383 return JNI_ENOMEM;
ysr@777 1384 }
ysr@777 1385 } else {
ysr@777 1386 _g1_rem_set = new StupidG1RemSet(this);
ysr@777 1387 }
ysr@777 1388
ysr@777 1389 // Carve out the G1 part of the heap.
ysr@777 1390
ysr@777 1391 ReservedSpace g1_rs = heap_rs.first_part(max_byte_size);
ysr@777 1392 _g1_reserved = MemRegion((HeapWord*)g1_rs.base(),
ysr@777 1393 g1_rs.size()/HeapWordSize);
ysr@777 1394 ReservedSpace perm_gen_rs = heap_rs.last_part(max_byte_size);
ysr@777 1395
ysr@777 1396 _perm_gen = pgs->init(perm_gen_rs, pgs->init_size(), rem_set());
ysr@777 1397
ysr@777 1398 _g1_storage.initialize(g1_rs, 0);
ysr@777 1399 _g1_committed = MemRegion((HeapWord*)_g1_storage.low(), (size_t) 0);
ysr@777 1400 _g1_max_committed = _g1_committed;
iveresov@828 1401 _hrs = new HeapRegionSeq(_expansion_regions);
ysr@777 1402 guarantee(_hrs != NULL, "Couldn't allocate HeapRegionSeq");
ysr@777 1403 guarantee(_cur_alloc_region == NULL, "from constructor");
ysr@777 1404
ysr@777 1405 _bot_shared = new G1BlockOffsetSharedArray(_reserved,
ysr@777 1406 heap_word_size(init_byte_size));
ysr@777 1407
ysr@777 1408 _g1h = this;
ysr@777 1409
ysr@777 1410 // Create the ConcurrentMark data structure and thread.
ysr@777 1411 // (Must do this late, so that "max_regions" is defined.)
ysr@777 1412 _cm = new ConcurrentMark(heap_rs, (int) max_regions());
ysr@777 1413 _cmThread = _cm->cmThread();
ysr@777 1414
ysr@777 1415 // ...and the concurrent zero-fill thread, if necessary.
ysr@777 1416 if (G1ConcZeroFill) {
ysr@777 1417 _czft = new ConcurrentZFThread();
ysr@777 1418 }
ysr@777 1419
ysr@777 1420
ysr@777 1421
ysr@777 1422 // Allocate the popular regions; take them off free lists.
ysr@777 1423 size_t pop_byte_size = G1NumPopularRegions * HeapRegion::GrainBytes;
ysr@777 1424 expand(pop_byte_size);
ysr@777 1425 _popular_object_boundary =
ysr@777 1426 _g1_reserved.start() + (G1NumPopularRegions * HeapRegion::GrainWords);
ysr@777 1427 for (int i = 0; i < G1NumPopularRegions; i++) {
ysr@777 1428 HeapRegion* hr = newAllocRegion(HeapRegion::GrainWords);
ysr@777 1429 // assert(hr != NULL && hr->bottom() < _popular_object_boundary,
ysr@777 1430 // "Should be enough, and all should be below boundary.");
ysr@777 1431 hr->set_popular(true);
ysr@777 1432 }
ysr@777 1433 assert(_cur_pop_hr_index == 0, "Start allocating at the first region.");
ysr@777 1434
ysr@777 1435 // Initialize the from_card cache structure of HeapRegionRemSet.
ysr@777 1436 HeapRegionRemSet::init_heap(max_regions());
ysr@777 1437
ysr@777 1438 // Now expand into the rest of the initial heap size.
ysr@777 1439 expand(init_byte_size - pop_byte_size);
ysr@777 1440
ysr@777 1441 // Perform any initialization actions delegated to the policy.
ysr@777 1442 g1_policy()->init();
ysr@777 1443
ysr@777 1444 g1_policy()->note_start_of_mark_thread();
ysr@777 1445
ysr@777 1446 _refine_cte_cl =
ysr@777 1447 new RefineCardTableEntryClosure(ConcurrentG1RefineThread::sts(),
ysr@777 1448 g1_rem_set(),
ysr@777 1449 concurrent_g1_refine());
ysr@777 1450 JavaThread::dirty_card_queue_set().set_closure(_refine_cte_cl);
ysr@777 1451
ysr@777 1452 JavaThread::satb_mark_queue_set().initialize(SATB_Q_CBL_mon,
ysr@777 1453 SATB_Q_FL_lock,
ysr@777 1454 0,
ysr@777 1455 Shared_SATB_Q_lock);
ysr@777 1456 if (G1RSBarrierUseQueue) {
ysr@777 1457 JavaThread::dirty_card_queue_set().initialize(DirtyCardQ_CBL_mon,
ysr@777 1458 DirtyCardQ_FL_lock,
ysr@777 1459 G1DirtyCardQueueMax,
ysr@777 1460 Shared_DirtyCardQ_lock);
ysr@777 1461 }
ysr@777 1462 // In case we're keeping closure specialization stats, initialize those
ysr@777 1463 // counts and that mechanism.
ysr@777 1464 SpecializationStats::clear();
ysr@777 1465
ysr@777 1466 _gc_alloc_region_list = NULL;
ysr@777 1467
ysr@777 1468 // Do later initialization work for concurrent refinement.
ysr@777 1469 _cg1r->init();
ysr@777 1470
ysr@777 1471 const char* group_names[] = { "CR", "ZF", "CM", "CL" };
ysr@777 1472 GCOverheadReporter::initGCOverheadReporter(4, group_names);
ysr@777 1473
ysr@777 1474 return JNI_OK;
ysr@777 1475 }
ysr@777 1476
ysr@777 1477 void G1CollectedHeap::ref_processing_init() {
ysr@777 1478 SharedHeap::ref_processing_init();
ysr@777 1479 MemRegion mr = reserved_region();
ysr@777 1480 _ref_processor = ReferenceProcessor::create_ref_processor(
ysr@777 1481 mr, // span
ysr@777 1482 false, // Reference discovery is not atomic
ysr@777 1483 // (though it shouldn't matter here.)
ysr@777 1484 true, // mt_discovery
ysr@777 1485 NULL, // is alive closure: need to fill this in for efficiency
ysr@777 1486 ParallelGCThreads,
ysr@777 1487 ParallelRefProcEnabled,
ysr@777 1488 true); // Setting next fields of discovered
ysr@777 1489 // lists requires a barrier.
ysr@777 1490 }
ysr@777 1491
ysr@777 1492 size_t G1CollectedHeap::capacity() const {
ysr@777 1493 return _g1_committed.byte_size();
ysr@777 1494 }
ysr@777 1495
ysr@777 1496 void G1CollectedHeap::iterate_dirty_card_closure(bool concurrent,
ysr@777 1497 int worker_i) {
ysr@777 1498 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set();
ysr@777 1499 int n_completed_buffers = 0;
ysr@777 1500 while (dcqs.apply_closure_to_completed_buffer(worker_i, 0, true)) {
ysr@777 1501 n_completed_buffers++;
ysr@777 1502 }
ysr@777 1503 g1_policy()->record_update_rs_processed_buffers(worker_i,
ysr@777 1504 (double) n_completed_buffers);
ysr@777 1505 dcqs.clear_n_completed_buffers();
ysr@777 1506 // Finish up the queue...
ysr@777 1507 if (worker_i == 0) concurrent_g1_refine()->clean_up_cache(worker_i,
ysr@777 1508 g1_rem_set());
ysr@777 1509 assert(!dcqs.completed_buffers_exist_dirty(), "Completed buffers exist!");
ysr@777 1510 }
ysr@777 1511
ysr@777 1512
ysr@777 1513 // Computes the sum of the storage used by the various regions.
ysr@777 1514
ysr@777 1515 size_t G1CollectedHeap::used() const {
ysr@777 1516 assert(Heap_lock->owner() != NULL,
ysr@777 1517 "Should be owned on this thread's behalf.");
ysr@777 1518 size_t result = _summary_bytes_used;
ysr@777 1519 if (_cur_alloc_region != NULL)
ysr@777 1520 result += _cur_alloc_region->used();
ysr@777 1521 return result;
ysr@777 1522 }
ysr@777 1523
ysr@777 1524 class SumUsedClosure: public HeapRegionClosure {
ysr@777 1525 size_t _used;
ysr@777 1526 public:
ysr@777 1527 SumUsedClosure() : _used(0) {}
ysr@777 1528 bool doHeapRegion(HeapRegion* r) {
ysr@777 1529 if (!r->continuesHumongous()) {
ysr@777 1530 _used += r->used();
ysr@777 1531 }
ysr@777 1532 return false;
ysr@777 1533 }
ysr@777 1534 size_t result() { return _used; }
ysr@777 1535 };
ysr@777 1536
ysr@777 1537 size_t G1CollectedHeap::recalculate_used() const {
ysr@777 1538 SumUsedClosure blk;
ysr@777 1539 _hrs->iterate(&blk);
ysr@777 1540 return blk.result();
ysr@777 1541 }
ysr@777 1542
ysr@777 1543 #ifndef PRODUCT
ysr@777 1544 class SumUsedRegionsClosure: public HeapRegionClosure {
ysr@777 1545 size_t _num;
ysr@777 1546 public:
ysr@777 1547 // _num is set to 1 to account for the popular region
ysr@777 1548 SumUsedRegionsClosure() : _num(G1NumPopularRegions) {}
ysr@777 1549 bool doHeapRegion(HeapRegion* r) {
ysr@777 1550 if (r->continuesHumongous() || r->used() > 0 || r->is_gc_alloc_region()) {
ysr@777 1551 _num += 1;
ysr@777 1552 }
ysr@777 1553 return false;
ysr@777 1554 }
ysr@777 1555 size_t result() { return _num; }
ysr@777 1556 };
ysr@777 1557
ysr@777 1558 size_t G1CollectedHeap::recalculate_used_regions() const {
ysr@777 1559 SumUsedRegionsClosure blk;
ysr@777 1560 _hrs->iterate(&blk);
ysr@777 1561 return blk.result();
ysr@777 1562 }
ysr@777 1563 #endif // PRODUCT
ysr@777 1564
ysr@777 1565 size_t G1CollectedHeap::unsafe_max_alloc() {
ysr@777 1566 if (_free_regions > 0) return HeapRegion::GrainBytes;
ysr@777 1567 // otherwise, is there space in the current allocation region?
ysr@777 1568
ysr@777 1569 // We need to store the current allocation region in a local variable
ysr@777 1570 // here. The problem is that this method doesn't take any locks and
ysr@777 1571 // there may be other threads which overwrite the current allocation
ysr@777 1572 // region field. attempt_allocation(), for example, sets it to NULL
ysr@777 1573 // and this can happen *after* the NULL check here but before the call
ysr@777 1574 // to free(), resulting in a SIGSEGV. Note that this doesn't appear
ysr@777 1575 // to be a problem in the optimized build, since the two loads of the
ysr@777 1576 // current allocation region field are optimized away.
ysr@777 1577 HeapRegion* car = _cur_alloc_region;
ysr@777 1578
ysr@777 1579 // FIXME: should iterate over all regions?
ysr@777 1580 if (car == NULL) {
ysr@777 1581 return 0;
ysr@777 1582 }
ysr@777 1583 return car->free();
ysr@777 1584 }
ysr@777 1585
ysr@777 1586 void G1CollectedHeap::collect(GCCause::Cause cause) {
ysr@777 1587 // The caller doesn't have the Heap_lock
ysr@777 1588 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
ysr@777 1589 MutexLocker ml(Heap_lock);
ysr@777 1590 collect_locked(cause);
ysr@777 1591 }
ysr@777 1592
ysr@777 1593 void G1CollectedHeap::collect_as_vm_thread(GCCause::Cause cause) {
ysr@777 1594 assert(Thread::current()->is_VM_thread(), "Precondition#1");
ysr@777 1595 assert(Heap_lock->is_locked(), "Precondition#2");
ysr@777 1596 GCCauseSetter gcs(this, cause);
ysr@777 1597 switch (cause) {
ysr@777 1598 case GCCause::_heap_inspection:
ysr@777 1599 case GCCause::_heap_dump: {
ysr@777 1600 HandleMark hm;
ysr@777 1601 do_full_collection(false); // don't clear all soft refs
ysr@777 1602 break;
ysr@777 1603 }
ysr@777 1604 default: // XXX FIX ME
ysr@777 1605 ShouldNotReachHere(); // Unexpected use of this function
ysr@777 1606 }
ysr@777 1607 }
ysr@777 1608
ysr@777 1609
ysr@777 1610 void G1CollectedHeap::collect_locked(GCCause::Cause cause) {
ysr@777 1611 // Don't want to do a GC until cleanup is completed.
ysr@777 1612 wait_for_cleanup_complete();
ysr@777 1613
ysr@777 1614 // Read the GC count while holding the Heap_lock
ysr@777 1615 int gc_count_before = SharedHeap::heap()->total_collections();
ysr@777 1616 {
ysr@777 1617 MutexUnlocker mu(Heap_lock); // give up heap lock, execute gets it back
ysr@777 1618 VM_G1CollectFull op(gc_count_before, cause);
ysr@777 1619 VMThread::execute(&op);
ysr@777 1620 }
ysr@777 1621 }
ysr@777 1622
ysr@777 1623 bool G1CollectedHeap::is_in(const void* p) const {
ysr@777 1624 if (_g1_committed.contains(p)) {
ysr@777 1625 HeapRegion* hr = _hrs->addr_to_region(p);
ysr@777 1626 return hr->is_in(p);
ysr@777 1627 } else {
ysr@777 1628 return _perm_gen->as_gen()->is_in(p);
ysr@777 1629 }
ysr@777 1630 }
ysr@777 1631
ysr@777 1632 // Iteration functions.
ysr@777 1633
ysr@777 1634 // Iterates an OopClosure over all ref-containing fields of objects
ysr@777 1635 // within a HeapRegion.
ysr@777 1636
ysr@777 1637 class IterateOopClosureRegionClosure: public HeapRegionClosure {
ysr@777 1638 MemRegion _mr;
ysr@777 1639 OopClosure* _cl;
ysr@777 1640 public:
ysr@777 1641 IterateOopClosureRegionClosure(MemRegion mr, OopClosure* cl)
ysr@777 1642 : _mr(mr), _cl(cl) {}
ysr@777 1643 bool doHeapRegion(HeapRegion* r) {
ysr@777 1644 if (! r->continuesHumongous()) {
ysr@777 1645 r->oop_iterate(_cl);
ysr@777 1646 }
ysr@777 1647 return false;
ysr@777 1648 }
ysr@777 1649 };
ysr@777 1650
ysr@777 1651 void G1CollectedHeap::oop_iterate(OopClosure* cl) {
ysr@777 1652 IterateOopClosureRegionClosure blk(_g1_committed, cl);
ysr@777 1653 _hrs->iterate(&blk);
ysr@777 1654 }
ysr@777 1655
ysr@777 1656 void G1CollectedHeap::oop_iterate(MemRegion mr, OopClosure* cl) {
ysr@777 1657 IterateOopClosureRegionClosure blk(mr, cl);
ysr@777 1658 _hrs->iterate(&blk);
ysr@777 1659 }
ysr@777 1660
ysr@777 1661 // Iterates an ObjectClosure over all objects within a HeapRegion.
ysr@777 1662
ysr@777 1663 class IterateObjectClosureRegionClosure: public HeapRegionClosure {
ysr@777 1664 ObjectClosure* _cl;
ysr@777 1665 public:
ysr@777 1666 IterateObjectClosureRegionClosure(ObjectClosure* cl) : _cl(cl) {}
ysr@777 1667 bool doHeapRegion(HeapRegion* r) {
ysr@777 1668 if (! r->continuesHumongous()) {
ysr@777 1669 r->object_iterate(_cl);
ysr@777 1670 }
ysr@777 1671 return false;
ysr@777 1672 }
ysr@777 1673 };
ysr@777 1674
ysr@777 1675 void G1CollectedHeap::object_iterate(ObjectClosure* cl) {
ysr@777 1676 IterateObjectClosureRegionClosure blk(cl);
ysr@777 1677 _hrs->iterate(&blk);
ysr@777 1678 }
ysr@777 1679
ysr@777 1680 void G1CollectedHeap::object_iterate_since_last_GC(ObjectClosure* cl) {
ysr@777 1681 // FIXME: is this right?
ysr@777 1682 guarantee(false, "object_iterate_since_last_GC not supported by G1 heap");
ysr@777 1683 }
ysr@777 1684
ysr@777 1685 // Calls a SpaceClosure on a HeapRegion.
ysr@777 1686
ysr@777 1687 class SpaceClosureRegionClosure: public HeapRegionClosure {
ysr@777 1688 SpaceClosure* _cl;
ysr@777 1689 public:
ysr@777 1690 SpaceClosureRegionClosure(SpaceClosure* cl) : _cl(cl) {}
ysr@777 1691 bool doHeapRegion(HeapRegion* r) {
ysr@777 1692 _cl->do_space(r);
ysr@777 1693 return false;
ysr@777 1694 }
ysr@777 1695 };
ysr@777 1696
ysr@777 1697 void G1CollectedHeap::space_iterate(SpaceClosure* cl) {
ysr@777 1698 SpaceClosureRegionClosure blk(cl);
ysr@777 1699 _hrs->iterate(&blk);
ysr@777 1700 }
ysr@777 1701
ysr@777 1702 void G1CollectedHeap::heap_region_iterate(HeapRegionClosure* cl) {
ysr@777 1703 _hrs->iterate(cl);
ysr@777 1704 }
ysr@777 1705
ysr@777 1706 void G1CollectedHeap::heap_region_iterate_from(HeapRegion* r,
ysr@777 1707 HeapRegionClosure* cl) {
ysr@777 1708 _hrs->iterate_from(r, cl);
ysr@777 1709 }
ysr@777 1710
ysr@777 1711 void
ysr@777 1712 G1CollectedHeap::heap_region_iterate_from(int idx, HeapRegionClosure* cl) {
ysr@777 1713 _hrs->iterate_from(idx, cl);
ysr@777 1714 }
ysr@777 1715
ysr@777 1716 HeapRegion* G1CollectedHeap::region_at(size_t idx) { return _hrs->at(idx); }
ysr@777 1717
ysr@777 1718 void
ysr@777 1719 G1CollectedHeap::heap_region_par_iterate_chunked(HeapRegionClosure* cl,
ysr@777 1720 int worker,
ysr@777 1721 jint claim_value) {
tonyp@790 1722 const size_t regions = n_regions();
tonyp@790 1723 const size_t worker_num = (ParallelGCThreads > 0 ? ParallelGCThreads : 1);
tonyp@790 1724 // try to spread out the starting points of the workers
tonyp@790 1725 const size_t start_index = regions / worker_num * (size_t) worker;
tonyp@790 1726
tonyp@790 1727 // each worker will actually look at all regions
tonyp@790 1728 for (size_t count = 0; count < regions; ++count) {
tonyp@790 1729 const size_t index = (start_index + count) % regions;
tonyp@790 1730 assert(0 <= index && index < regions, "sanity");
tonyp@790 1731 HeapRegion* r = region_at(index);
tonyp@790 1732 // we'll ignore "continues humongous" regions (we'll process them
tonyp@790 1733 // when we come across their corresponding "start humongous"
tonyp@790 1734 // region) and regions already claimed
tonyp@790 1735 if (r->claim_value() == claim_value || r->continuesHumongous()) {
tonyp@790 1736 continue;
tonyp@790 1737 }
tonyp@790 1738 // OK, try to claim it
ysr@777 1739 if (r->claimHeapRegion(claim_value)) {
tonyp@790 1740 // success!
tonyp@790 1741 assert(!r->continuesHumongous(), "sanity");
tonyp@790 1742 if (r->startsHumongous()) {
tonyp@790 1743 // If the region is "starts humongous" we'll iterate over its
tonyp@790 1744 // "continues humongous" first; in fact we'll do them
tonyp@790 1745 // first. The order is important. In on case, calling the
tonyp@790 1746 // closure on the "starts humongous" region might de-allocate
tonyp@790 1747 // and clear all its "continues humongous" regions and, as a
tonyp@790 1748 // result, we might end up processing them twice. So, we'll do
tonyp@790 1749 // them first (notice: most closures will ignore them anyway) and
tonyp@790 1750 // then we'll do the "starts humongous" region.
tonyp@790 1751 for (size_t ch_index = index + 1; ch_index < regions; ++ch_index) {
tonyp@790 1752 HeapRegion* chr = region_at(ch_index);
tonyp@790 1753
tonyp@790 1754 // if the region has already been claimed or it's not
tonyp@790 1755 // "continues humongous" we're done
tonyp@790 1756 if (chr->claim_value() == claim_value ||
tonyp@790 1757 !chr->continuesHumongous()) {
tonyp@790 1758 break;
tonyp@790 1759 }
tonyp@790 1760
tonyp@790 1761 // Noone should have claimed it directly. We can given
tonyp@790 1762 // that we claimed its "starts humongous" region.
tonyp@790 1763 assert(chr->claim_value() != claim_value, "sanity");
tonyp@790 1764 assert(chr->humongous_start_region() == r, "sanity");
tonyp@790 1765
tonyp@790 1766 if (chr->claimHeapRegion(claim_value)) {
tonyp@790 1767 // we should always be able to claim it; noone else should
tonyp@790 1768 // be trying to claim this region
tonyp@790 1769
tonyp@790 1770 bool res2 = cl->doHeapRegion(chr);
tonyp@790 1771 assert(!res2, "Should not abort");
tonyp@790 1772
tonyp@790 1773 // Right now, this holds (i.e., no closure that actually
tonyp@790 1774 // does something with "continues humongous" regions
tonyp@790 1775 // clears them). We might have to weaken it in the future,
tonyp@790 1776 // but let's leave these two asserts here for extra safety.
tonyp@790 1777 assert(chr->continuesHumongous(), "should still be the case");
tonyp@790 1778 assert(chr->humongous_start_region() == r, "sanity");
tonyp@790 1779 } else {
tonyp@790 1780 guarantee(false, "we should not reach here");
tonyp@790 1781 }
tonyp@790 1782 }
tonyp@790 1783 }
tonyp@790 1784
tonyp@790 1785 assert(!r->continuesHumongous(), "sanity");
tonyp@790 1786 bool res = cl->doHeapRegion(r);
tonyp@790 1787 assert(!res, "Should not abort");
tonyp@790 1788 }
tonyp@790 1789 }
tonyp@790 1790 }
tonyp@790 1791
tonyp@825 1792 class ResetClaimValuesClosure: public HeapRegionClosure {
tonyp@825 1793 public:
tonyp@825 1794 bool doHeapRegion(HeapRegion* r) {
tonyp@825 1795 r->set_claim_value(HeapRegion::InitialClaimValue);
tonyp@825 1796 return false;
tonyp@825 1797 }
tonyp@825 1798 };
tonyp@825 1799
tonyp@825 1800 void
tonyp@825 1801 G1CollectedHeap::reset_heap_region_claim_values() {
tonyp@825 1802 ResetClaimValuesClosure blk;
tonyp@825 1803 heap_region_iterate(&blk);
tonyp@825 1804 }
tonyp@825 1805
tonyp@790 1806 #ifdef ASSERT
tonyp@790 1807 // This checks whether all regions in the heap have the correct claim
tonyp@790 1808 // value. I also piggy-backed on this a check to ensure that the
tonyp@790 1809 // humongous_start_region() information on "continues humongous"
tonyp@790 1810 // regions is correct.
tonyp@790 1811
tonyp@790 1812 class CheckClaimValuesClosure : public HeapRegionClosure {
tonyp@790 1813 private:
tonyp@790 1814 jint _claim_value;
tonyp@790 1815 size_t _failures;
tonyp@790 1816 HeapRegion* _sh_region;
tonyp@790 1817 public:
tonyp@790 1818 CheckClaimValuesClosure(jint claim_value) :
tonyp@790 1819 _claim_value(claim_value), _failures(0), _sh_region(NULL) { }
tonyp@790 1820 bool doHeapRegion(HeapRegion* r) {
tonyp@790 1821 if (r->claim_value() != _claim_value) {
tonyp@790 1822 gclog_or_tty->print_cr("Region ["PTR_FORMAT","PTR_FORMAT"), "
tonyp@790 1823 "claim value = %d, should be %d",
tonyp@790 1824 r->bottom(), r->end(), r->claim_value(),
tonyp@790 1825 _claim_value);
tonyp@790 1826 ++_failures;
tonyp@790 1827 }
tonyp@790 1828 if (!r->isHumongous()) {
tonyp@790 1829 _sh_region = NULL;
tonyp@790 1830 } else if (r->startsHumongous()) {
tonyp@790 1831 _sh_region = r;
tonyp@790 1832 } else if (r->continuesHumongous()) {
tonyp@790 1833 if (r->humongous_start_region() != _sh_region) {
tonyp@790 1834 gclog_or_tty->print_cr("Region ["PTR_FORMAT","PTR_FORMAT"), "
tonyp@790 1835 "HS = "PTR_FORMAT", should be "PTR_FORMAT,
tonyp@790 1836 r->bottom(), r->end(),
tonyp@790 1837 r->humongous_start_region(),
tonyp@790 1838 _sh_region);
tonyp@790 1839 ++_failures;
ysr@777 1840 }
ysr@777 1841 }
tonyp@790 1842 return false;
tonyp@790 1843 }
tonyp@790 1844 size_t failures() {
tonyp@790 1845 return _failures;
tonyp@790 1846 }
tonyp@790 1847 };
tonyp@790 1848
tonyp@790 1849 bool G1CollectedHeap::check_heap_region_claim_values(jint claim_value) {
tonyp@790 1850 CheckClaimValuesClosure cl(claim_value);
tonyp@790 1851 heap_region_iterate(&cl);
tonyp@790 1852 return cl.failures() == 0;
tonyp@790 1853 }
tonyp@790 1854 #endif // ASSERT
ysr@777 1855
ysr@777 1856 void G1CollectedHeap::collection_set_iterate(HeapRegionClosure* cl) {
ysr@777 1857 HeapRegion* r = g1_policy()->collection_set();
ysr@777 1858 while (r != NULL) {
ysr@777 1859 HeapRegion* next = r->next_in_collection_set();
ysr@777 1860 if (cl->doHeapRegion(r)) {
ysr@777 1861 cl->incomplete();
ysr@777 1862 return;
ysr@777 1863 }
ysr@777 1864 r = next;
ysr@777 1865 }
ysr@777 1866 }
ysr@777 1867
ysr@777 1868 void G1CollectedHeap::collection_set_iterate_from(HeapRegion* r,
ysr@777 1869 HeapRegionClosure *cl) {
ysr@777 1870 assert(r->in_collection_set(),
ysr@777 1871 "Start region must be a member of the collection set.");
ysr@777 1872 HeapRegion* cur = r;
ysr@777 1873 while (cur != NULL) {
ysr@777 1874 HeapRegion* next = cur->next_in_collection_set();
ysr@777 1875 if (cl->doHeapRegion(cur) && false) {
ysr@777 1876 cl->incomplete();
ysr@777 1877 return;
ysr@777 1878 }
ysr@777 1879 cur = next;
ysr@777 1880 }
ysr@777 1881 cur = g1_policy()->collection_set();
ysr@777 1882 while (cur != r) {
ysr@777 1883 HeapRegion* next = cur->next_in_collection_set();
ysr@777 1884 if (cl->doHeapRegion(cur) && false) {
ysr@777 1885 cl->incomplete();
ysr@777 1886 return;
ysr@777 1887 }
ysr@777 1888 cur = next;
ysr@777 1889 }
ysr@777 1890 }
ysr@777 1891
ysr@777 1892 CompactibleSpace* G1CollectedHeap::first_compactible_space() {
ysr@777 1893 return _hrs->length() > 0 ? _hrs->at(0) : NULL;
ysr@777 1894 }
ysr@777 1895
ysr@777 1896
ysr@777 1897 Space* G1CollectedHeap::space_containing(const void* addr) const {
ysr@777 1898 Space* res = heap_region_containing(addr);
ysr@777 1899 if (res == NULL)
ysr@777 1900 res = perm_gen()->space_containing(addr);
ysr@777 1901 return res;
ysr@777 1902 }
ysr@777 1903
ysr@777 1904 HeapWord* G1CollectedHeap::block_start(const void* addr) const {
ysr@777 1905 Space* sp = space_containing(addr);
ysr@777 1906 if (sp != NULL) {
ysr@777 1907 return sp->block_start(addr);
ysr@777 1908 }
ysr@777 1909 return NULL;
ysr@777 1910 }
ysr@777 1911
ysr@777 1912 size_t G1CollectedHeap::block_size(const HeapWord* addr) const {
ysr@777 1913 Space* sp = space_containing(addr);
ysr@777 1914 assert(sp != NULL, "block_size of address outside of heap");
ysr@777 1915 return sp->block_size(addr);
ysr@777 1916 }
ysr@777 1917
ysr@777 1918 bool G1CollectedHeap::block_is_obj(const HeapWord* addr) const {
ysr@777 1919 Space* sp = space_containing(addr);
ysr@777 1920 return sp->block_is_obj(addr);
ysr@777 1921 }
ysr@777 1922
ysr@777 1923 bool G1CollectedHeap::supports_tlab_allocation() const {
ysr@777 1924 return true;
ysr@777 1925 }
ysr@777 1926
ysr@777 1927 size_t G1CollectedHeap::tlab_capacity(Thread* ignored) const {
ysr@777 1928 return HeapRegion::GrainBytes;
ysr@777 1929 }
ysr@777 1930
ysr@777 1931 size_t G1CollectedHeap::unsafe_max_tlab_alloc(Thread* ignored) const {
ysr@777 1932 // Return the remaining space in the cur alloc region, but not less than
ysr@777 1933 // the min TLAB size.
ysr@777 1934 // Also, no more than half the region size, since we can't allow tlabs to
ysr@777 1935 // grow big enough to accomodate humongous objects.
ysr@777 1936
ysr@777 1937 // We need to story it locally, since it might change between when we
ysr@777 1938 // test for NULL and when we use it later.
ysr@777 1939 ContiguousSpace* cur_alloc_space = _cur_alloc_region;
ysr@777 1940 if (cur_alloc_space == NULL) {
ysr@777 1941 return HeapRegion::GrainBytes/2;
ysr@777 1942 } else {
ysr@777 1943 return MAX2(MIN2(cur_alloc_space->free(),
ysr@777 1944 (size_t)(HeapRegion::GrainBytes/2)),
ysr@777 1945 (size_t)MinTLABSize);
ysr@777 1946 }
ysr@777 1947 }
ysr@777 1948
ysr@777 1949 HeapWord* G1CollectedHeap::allocate_new_tlab(size_t size) {
ysr@777 1950 bool dummy;
ysr@777 1951 return G1CollectedHeap::mem_allocate(size, false, true, &dummy);
ysr@777 1952 }
ysr@777 1953
ysr@777 1954 bool G1CollectedHeap::allocs_are_zero_filled() {
ysr@777 1955 return false;
ysr@777 1956 }
ysr@777 1957
ysr@777 1958 size_t G1CollectedHeap::large_typearray_limit() {
ysr@777 1959 // FIXME
ysr@777 1960 return HeapRegion::GrainBytes/HeapWordSize;
ysr@777 1961 }
ysr@777 1962
ysr@777 1963 size_t G1CollectedHeap::max_capacity() const {
ysr@777 1964 return _g1_committed.byte_size();
ysr@777 1965 }
ysr@777 1966
ysr@777 1967 jlong G1CollectedHeap::millis_since_last_gc() {
ysr@777 1968 // assert(false, "NYI");
ysr@777 1969 return 0;
ysr@777 1970 }
ysr@777 1971
ysr@777 1972
ysr@777 1973 void G1CollectedHeap::prepare_for_verify() {
ysr@777 1974 if (SafepointSynchronize::is_at_safepoint() || ! UseTLAB) {
ysr@777 1975 ensure_parsability(false);
ysr@777 1976 }
ysr@777 1977 g1_rem_set()->prepare_for_verify();
ysr@777 1978 }
ysr@777 1979
ysr@777 1980 class VerifyLivenessOopClosure: public OopClosure {
ysr@777 1981 G1CollectedHeap* g1h;
ysr@777 1982 public:
ysr@777 1983 VerifyLivenessOopClosure(G1CollectedHeap* _g1h) {
ysr@777 1984 g1h = _g1h;
ysr@777 1985 }
ysr@777 1986 void do_oop(narrowOop *p) {
ysr@777 1987 guarantee(false, "NYI");
ysr@777 1988 }
ysr@777 1989 void do_oop(oop *p) {
ysr@777 1990 oop obj = *p;
ysr@777 1991 assert(obj == NULL || !g1h->is_obj_dead(obj),
ysr@777 1992 "Dead object referenced by a not dead object");
ysr@777 1993 }
ysr@777 1994 };
ysr@777 1995
ysr@777 1996 class VerifyObjsInRegionClosure: public ObjectClosure {
ysr@777 1997 G1CollectedHeap* _g1h;
ysr@777 1998 size_t _live_bytes;
ysr@777 1999 HeapRegion *_hr;
ysr@777 2000 public:
ysr@777 2001 VerifyObjsInRegionClosure(HeapRegion *hr) : _live_bytes(0), _hr(hr) {
ysr@777 2002 _g1h = G1CollectedHeap::heap();
ysr@777 2003 }
ysr@777 2004 void do_object(oop o) {
ysr@777 2005 VerifyLivenessOopClosure isLive(_g1h);
ysr@777 2006 assert(o != NULL, "Huh?");
ysr@777 2007 if (!_g1h->is_obj_dead(o)) {
ysr@777 2008 o->oop_iterate(&isLive);
ysr@777 2009 if (!_hr->obj_allocated_since_prev_marking(o))
ysr@777 2010 _live_bytes += (o->size() * HeapWordSize);
ysr@777 2011 }
ysr@777 2012 }
ysr@777 2013 size_t live_bytes() { return _live_bytes; }
ysr@777 2014 };
ysr@777 2015
ysr@777 2016 class PrintObjsInRegionClosure : public ObjectClosure {
ysr@777 2017 HeapRegion *_hr;
ysr@777 2018 G1CollectedHeap *_g1;
ysr@777 2019 public:
ysr@777 2020 PrintObjsInRegionClosure(HeapRegion *hr) : _hr(hr) {
ysr@777 2021 _g1 = G1CollectedHeap::heap();
ysr@777 2022 };
ysr@777 2023
ysr@777 2024 void do_object(oop o) {
ysr@777 2025 if (o != NULL) {
ysr@777 2026 HeapWord *start = (HeapWord *) o;
ysr@777 2027 size_t word_sz = o->size();
ysr@777 2028 gclog_or_tty->print("\nPrinting obj "PTR_FORMAT" of size " SIZE_FORMAT
ysr@777 2029 " isMarkedPrev %d isMarkedNext %d isAllocSince %d\n",
ysr@777 2030 (void*) o, word_sz,
ysr@777 2031 _g1->isMarkedPrev(o),
ysr@777 2032 _g1->isMarkedNext(o),
ysr@777 2033 _hr->obj_allocated_since_prev_marking(o));
ysr@777 2034 HeapWord *end = start + word_sz;
ysr@777 2035 HeapWord *cur;
ysr@777 2036 int *val;
ysr@777 2037 for (cur = start; cur < end; cur++) {
ysr@777 2038 val = (int *) cur;
ysr@777 2039 gclog_or_tty->print("\t "PTR_FORMAT":"PTR_FORMAT"\n", val, *val);
ysr@777 2040 }
ysr@777 2041 }
ysr@777 2042 }
ysr@777 2043 };
ysr@777 2044
ysr@777 2045 class VerifyRegionClosure: public HeapRegionClosure {
ysr@777 2046 public:
ysr@777 2047 bool _allow_dirty;
tonyp@825 2048 bool _par;
tonyp@825 2049 VerifyRegionClosure(bool allow_dirty, bool par = false)
tonyp@825 2050 : _allow_dirty(allow_dirty), _par(par) {}
ysr@777 2051 bool doHeapRegion(HeapRegion* r) {
tonyp@825 2052 guarantee(_par || r->claim_value() == HeapRegion::InitialClaimValue,
tonyp@825 2053 "Should be unclaimed at verify points.");
ysr@777 2054 if (r->isHumongous()) {
ysr@777 2055 if (r->startsHumongous()) {
ysr@777 2056 // Verify the single H object.
ysr@777 2057 oop(r->bottom())->verify();
ysr@777 2058 size_t word_sz = oop(r->bottom())->size();
ysr@777 2059 guarantee(r->top() == r->bottom() + word_sz,
ysr@777 2060 "Only one object in a humongous region");
ysr@777 2061 }
ysr@777 2062 } else {
ysr@777 2063 VerifyObjsInRegionClosure not_dead_yet_cl(r);
ysr@777 2064 r->verify(_allow_dirty);
ysr@777 2065 r->object_iterate(&not_dead_yet_cl);
ysr@777 2066 guarantee(r->max_live_bytes() >= not_dead_yet_cl.live_bytes(),
ysr@777 2067 "More live objects than counted in last complete marking.");
ysr@777 2068 }
ysr@777 2069 return false;
ysr@777 2070 }
ysr@777 2071 };
ysr@777 2072
ysr@777 2073 class VerifyRootsClosure: public OopsInGenClosure {
ysr@777 2074 private:
ysr@777 2075 G1CollectedHeap* _g1h;
ysr@777 2076 bool _failures;
ysr@777 2077
ysr@777 2078 public:
ysr@777 2079 VerifyRootsClosure() :
ysr@777 2080 _g1h(G1CollectedHeap::heap()), _failures(false) { }
ysr@777 2081
ysr@777 2082 bool failures() { return _failures; }
ysr@777 2083
ysr@777 2084 void do_oop(narrowOop* p) {
ysr@777 2085 guarantee(false, "NYI");
ysr@777 2086 }
ysr@777 2087
ysr@777 2088 void do_oop(oop* p) {
ysr@777 2089 oop obj = *p;
ysr@777 2090 if (obj != NULL) {
ysr@777 2091 if (_g1h->is_obj_dead(obj)) {
ysr@777 2092 gclog_or_tty->print_cr("Root location "PTR_FORMAT" "
ysr@777 2093 "points to dead obj "PTR_FORMAT, p, (void*) obj);
ysr@777 2094 obj->print_on(gclog_or_tty);
ysr@777 2095 _failures = true;
ysr@777 2096 }
ysr@777 2097 }
ysr@777 2098 }
ysr@777 2099 };
ysr@777 2100
tonyp@825 2101 // This is the task used for parallel heap verification.
tonyp@825 2102
tonyp@825 2103 class G1ParVerifyTask: public AbstractGangTask {
tonyp@825 2104 private:
tonyp@825 2105 G1CollectedHeap* _g1h;
tonyp@825 2106 bool _allow_dirty;
tonyp@825 2107
tonyp@825 2108 public:
tonyp@825 2109 G1ParVerifyTask(G1CollectedHeap* g1h, bool allow_dirty) :
tonyp@825 2110 AbstractGangTask("Parallel verify task"),
tonyp@825 2111 _g1h(g1h), _allow_dirty(allow_dirty) { }
tonyp@825 2112
tonyp@825 2113 void work(int worker_i) {
tonyp@825 2114 VerifyRegionClosure blk(_allow_dirty, true);
tonyp@825 2115 _g1h->heap_region_par_iterate_chunked(&blk, worker_i,
tonyp@825 2116 HeapRegion::ParVerifyClaimValue);
tonyp@825 2117 }
tonyp@825 2118 };
tonyp@825 2119
ysr@777 2120 void G1CollectedHeap::verify(bool allow_dirty, bool silent) {
ysr@777 2121 if (SafepointSynchronize::is_at_safepoint() || ! UseTLAB) {
ysr@777 2122 if (!silent) { gclog_or_tty->print("roots "); }
ysr@777 2123 VerifyRootsClosure rootsCl;
ysr@777 2124 process_strong_roots(false,
ysr@777 2125 SharedHeap::SO_AllClasses,
ysr@777 2126 &rootsCl,
ysr@777 2127 &rootsCl);
ysr@777 2128 rem_set()->invalidate(perm_gen()->used_region(), false);
ysr@777 2129 if (!silent) { gclog_or_tty->print("heapRegions "); }
tonyp@825 2130 if (GCParallelVerificationEnabled && ParallelGCThreads > 1) {
tonyp@825 2131 assert(check_heap_region_claim_values(HeapRegion::InitialClaimValue),
tonyp@825 2132 "sanity check");
tonyp@825 2133
tonyp@825 2134 G1ParVerifyTask task(this, allow_dirty);
tonyp@825 2135 int n_workers = workers()->total_workers();
tonyp@825 2136 set_par_threads(n_workers);
tonyp@825 2137 workers()->run_task(&task);
tonyp@825 2138 set_par_threads(0);
tonyp@825 2139
tonyp@825 2140 assert(check_heap_region_claim_values(HeapRegion::ParVerifyClaimValue),
tonyp@825 2141 "sanity check");
tonyp@825 2142
tonyp@825 2143 reset_heap_region_claim_values();
tonyp@825 2144
tonyp@825 2145 assert(check_heap_region_claim_values(HeapRegion::InitialClaimValue),
tonyp@825 2146 "sanity check");
tonyp@825 2147 } else {
tonyp@825 2148 VerifyRegionClosure blk(allow_dirty);
tonyp@825 2149 _hrs->iterate(&blk);
tonyp@825 2150 }
ysr@777 2151 if (!silent) gclog_or_tty->print("remset ");
ysr@777 2152 rem_set()->verify();
ysr@777 2153 guarantee(!rootsCl.failures(), "should not have had failures");
ysr@777 2154 } else {
ysr@777 2155 if (!silent) gclog_or_tty->print("(SKIPPING roots, heapRegions, remset) ");
ysr@777 2156 }
ysr@777 2157 }
ysr@777 2158
ysr@777 2159 class PrintRegionClosure: public HeapRegionClosure {
ysr@777 2160 outputStream* _st;
ysr@777 2161 public:
ysr@777 2162 PrintRegionClosure(outputStream* st) : _st(st) {}
ysr@777 2163 bool doHeapRegion(HeapRegion* r) {
ysr@777 2164 r->print_on(_st);
ysr@777 2165 return false;
ysr@777 2166 }
ysr@777 2167 };
ysr@777 2168
ysr@777 2169 void G1CollectedHeap::print() const { print_on(gclog_or_tty); }
ysr@777 2170
ysr@777 2171 void G1CollectedHeap::print_on(outputStream* st) const {
ysr@777 2172 PrintRegionClosure blk(st);
ysr@777 2173 _hrs->iterate(&blk);
ysr@777 2174 }
ysr@777 2175
ysr@777 2176 void G1CollectedHeap::print_gc_threads_on(outputStream* st) const {
ysr@777 2177 if (ParallelGCThreads > 0) {
ysr@777 2178 workers()->print_worker_threads();
ysr@777 2179 }
ysr@777 2180 st->print("\"G1 concurrent mark GC Thread\" ");
ysr@777 2181 _cmThread->print();
ysr@777 2182 st->cr();
ysr@777 2183 st->print("\"G1 concurrent refinement GC Thread\" ");
ysr@777 2184 _cg1r->cg1rThread()->print_on(st);
ysr@777 2185 st->cr();
ysr@777 2186 st->print("\"G1 zero-fill GC Thread\" ");
ysr@777 2187 _czft->print_on(st);
ysr@777 2188 st->cr();
ysr@777 2189 }
ysr@777 2190
ysr@777 2191 void G1CollectedHeap::gc_threads_do(ThreadClosure* tc) const {
ysr@777 2192 if (ParallelGCThreads > 0) {
ysr@777 2193 workers()->threads_do(tc);
ysr@777 2194 }
ysr@777 2195 tc->do_thread(_cmThread);
ysr@777 2196 tc->do_thread(_cg1r->cg1rThread());
ysr@777 2197 tc->do_thread(_czft);
ysr@777 2198 }
ysr@777 2199
ysr@777 2200 void G1CollectedHeap::print_tracing_info() const {
ysr@777 2201 concurrent_g1_refine()->print_final_card_counts();
ysr@777 2202
ysr@777 2203 // We'll overload this to mean "trace GC pause statistics."
ysr@777 2204 if (TraceGen0Time || TraceGen1Time) {
ysr@777 2205 // The "G1CollectorPolicy" is keeping track of these stats, so delegate
ysr@777 2206 // to that.
ysr@777 2207 g1_policy()->print_tracing_info();
ysr@777 2208 }
ysr@777 2209 if (SummarizeG1RSStats) {
ysr@777 2210 g1_rem_set()->print_summary_info();
ysr@777 2211 }
ysr@777 2212 if (SummarizeG1ConcMark) {
ysr@777 2213 concurrent_mark()->print_summary_info();
ysr@777 2214 }
ysr@777 2215 if (SummarizeG1ZFStats) {
ysr@777 2216 ConcurrentZFThread::print_summary_info();
ysr@777 2217 }
ysr@777 2218 if (G1SummarizePopularity) {
ysr@777 2219 print_popularity_summary_info();
ysr@777 2220 }
ysr@777 2221 g1_policy()->print_yg_surv_rate_info();
ysr@777 2222
ysr@777 2223 GCOverheadReporter::printGCOverhead();
ysr@777 2224
ysr@777 2225 SpecializationStats::print();
ysr@777 2226 }
ysr@777 2227
ysr@777 2228
ysr@777 2229 int G1CollectedHeap::addr_to_arena_id(void* addr) const {
ysr@777 2230 HeapRegion* hr = heap_region_containing(addr);
ysr@777 2231 if (hr == NULL) {
ysr@777 2232 return 0;
ysr@777 2233 } else {
ysr@777 2234 return 1;
ysr@777 2235 }
ysr@777 2236 }
ysr@777 2237
ysr@777 2238 G1CollectedHeap* G1CollectedHeap::heap() {
ysr@777 2239 assert(_sh->kind() == CollectedHeap::G1CollectedHeap,
ysr@777 2240 "not a garbage-first heap");
ysr@777 2241 return _g1h;
ysr@777 2242 }
ysr@777 2243
ysr@777 2244 void G1CollectedHeap::gc_prologue(bool full /* Ignored */) {
ysr@777 2245 if (PrintHeapAtGC){
ysr@777 2246 gclog_or_tty->print_cr(" {Heap before GC collections=%d:", total_collections());
ysr@777 2247 Universe::print();
ysr@777 2248 }
ysr@777 2249 assert(InlineCacheBuffer::is_empty(), "should have cleaned up ICBuffer");
ysr@777 2250 // Call allocation profiler
ysr@777 2251 AllocationProfiler::iterate_since_last_gc();
ysr@777 2252 // Fill TLAB's and such
ysr@777 2253 ensure_parsability(true);
ysr@777 2254 }
ysr@777 2255
ysr@777 2256 void G1CollectedHeap::gc_epilogue(bool full /* Ignored */) {
ysr@777 2257 // FIXME: what is this about?
ysr@777 2258 // I'm ignoring the "fill_newgen()" call if "alloc_event_enabled"
ysr@777 2259 // is set.
ysr@777 2260 COMPILER2_PRESENT(assert(DerivedPointerTable::is_empty(),
ysr@777 2261 "derived pointer present"));
ysr@777 2262
ysr@777 2263 if (PrintHeapAtGC){
ysr@777 2264 gclog_or_tty->print_cr(" Heap after GC collections=%d:", total_collections());
ysr@777 2265 Universe::print();
ysr@777 2266 gclog_or_tty->print("} ");
ysr@777 2267 }
ysr@777 2268 }
ysr@777 2269
ysr@777 2270 void G1CollectedHeap::do_collection_pause() {
ysr@777 2271 // Read the GC count while holding the Heap_lock
ysr@777 2272 // we need to do this _before_ wait_for_cleanup_complete(), to
ysr@777 2273 // ensure that we do not give up the heap lock and potentially
ysr@777 2274 // pick up the wrong count
ysr@777 2275 int gc_count_before = SharedHeap::heap()->total_collections();
ysr@777 2276
ysr@777 2277 // Don't want to do a GC pause while cleanup is being completed!
ysr@777 2278 wait_for_cleanup_complete();
ysr@777 2279
ysr@777 2280 g1_policy()->record_stop_world_start();
ysr@777 2281 {
ysr@777 2282 MutexUnlocker mu(Heap_lock); // give up heap lock, execute gets it back
ysr@777 2283 VM_G1IncCollectionPause op(gc_count_before);
ysr@777 2284 VMThread::execute(&op);
ysr@777 2285 }
ysr@777 2286 }
ysr@777 2287
ysr@777 2288 void
ysr@777 2289 G1CollectedHeap::doConcurrentMark() {
ysr@777 2290 if (G1ConcMark) {
ysr@777 2291 MutexLockerEx x(CGC_lock, Mutex::_no_safepoint_check_flag);
ysr@777 2292 if (!_cmThread->in_progress()) {
ysr@777 2293 _cmThread->set_started();
ysr@777 2294 CGC_lock->notify();
ysr@777 2295 }
ysr@777 2296 }
ysr@777 2297 }
ysr@777 2298
ysr@777 2299 class VerifyMarkedObjsClosure: public ObjectClosure {
ysr@777 2300 G1CollectedHeap* _g1h;
ysr@777 2301 public:
ysr@777 2302 VerifyMarkedObjsClosure(G1CollectedHeap* g1h) : _g1h(g1h) {}
ysr@777 2303 void do_object(oop obj) {
ysr@777 2304 assert(obj->mark()->is_marked() ? !_g1h->is_obj_dead(obj) : true,
ysr@777 2305 "markandsweep mark should agree with concurrent deadness");
ysr@777 2306 }
ysr@777 2307 };
ysr@777 2308
ysr@777 2309 void
ysr@777 2310 G1CollectedHeap::checkConcurrentMark() {
ysr@777 2311 VerifyMarkedObjsClosure verifycl(this);
ysr@777 2312 doConcurrentMark();
ysr@777 2313 // MutexLockerEx x(getMarkBitMapLock(),
ysr@777 2314 // Mutex::_no_safepoint_check_flag);
ysr@777 2315 object_iterate(&verifycl);
ysr@777 2316 }
ysr@777 2317
ysr@777 2318 void G1CollectedHeap::do_sync_mark() {
ysr@777 2319 _cm->checkpointRootsInitial();
ysr@777 2320 _cm->markFromRoots();
ysr@777 2321 _cm->checkpointRootsFinal(false);
ysr@777 2322 }
ysr@777 2323
ysr@777 2324 // <NEW PREDICTION>
ysr@777 2325
ysr@777 2326 double G1CollectedHeap::predict_region_elapsed_time_ms(HeapRegion *hr,
ysr@777 2327 bool young) {
ysr@777 2328 return _g1_policy->predict_region_elapsed_time_ms(hr, young);
ysr@777 2329 }
ysr@777 2330
ysr@777 2331 void G1CollectedHeap::check_if_region_is_too_expensive(double
ysr@777 2332 predicted_time_ms) {
ysr@777 2333 _g1_policy->check_if_region_is_too_expensive(predicted_time_ms);
ysr@777 2334 }
ysr@777 2335
ysr@777 2336 size_t G1CollectedHeap::pending_card_num() {
ysr@777 2337 size_t extra_cards = 0;
ysr@777 2338 JavaThread *curr = Threads::first();
ysr@777 2339 while (curr != NULL) {
ysr@777 2340 DirtyCardQueue& dcq = curr->dirty_card_queue();
ysr@777 2341 extra_cards += dcq.size();
ysr@777 2342 curr = curr->next();
ysr@777 2343 }
ysr@777 2344 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set();
ysr@777 2345 size_t buffer_size = dcqs.buffer_size();
ysr@777 2346 size_t buffer_num = dcqs.completed_buffers_num();
ysr@777 2347 return buffer_size * buffer_num + extra_cards;
ysr@777 2348 }
ysr@777 2349
ysr@777 2350 size_t G1CollectedHeap::max_pending_card_num() {
ysr@777 2351 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set();
ysr@777 2352 size_t buffer_size = dcqs.buffer_size();
ysr@777 2353 size_t buffer_num = dcqs.completed_buffers_num();
ysr@777 2354 int thread_num = Threads::number_of_threads();
ysr@777 2355 return (buffer_num + thread_num) * buffer_size;
ysr@777 2356 }
ysr@777 2357
ysr@777 2358 size_t G1CollectedHeap::cards_scanned() {
ysr@777 2359 HRInto_G1RemSet* g1_rset = (HRInto_G1RemSet*) g1_rem_set();
ysr@777 2360 return g1_rset->cardsScanned();
ysr@777 2361 }
ysr@777 2362
ysr@777 2363 void
ysr@777 2364 G1CollectedHeap::setup_surviving_young_words() {
ysr@777 2365 guarantee( _surviving_young_words == NULL, "pre-condition" );
ysr@777 2366 size_t array_length = g1_policy()->young_cset_length();
ysr@777 2367 _surviving_young_words = NEW_C_HEAP_ARRAY(size_t, array_length);
ysr@777 2368 if (_surviving_young_words == NULL) {
ysr@777 2369 vm_exit_out_of_memory(sizeof(size_t) * array_length,
ysr@777 2370 "Not enough space for young surv words summary.");
ysr@777 2371 }
ysr@777 2372 memset(_surviving_young_words, 0, array_length * sizeof(size_t));
ysr@777 2373 for (size_t i = 0; i < array_length; ++i) {
ysr@777 2374 guarantee( _surviving_young_words[i] == 0, "invariant" );
ysr@777 2375 }
ysr@777 2376 }
ysr@777 2377
ysr@777 2378 void
ysr@777 2379 G1CollectedHeap::update_surviving_young_words(size_t* surv_young_words) {
ysr@777 2380 MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag);
ysr@777 2381 size_t array_length = g1_policy()->young_cset_length();
ysr@777 2382 for (size_t i = 0; i < array_length; ++i)
ysr@777 2383 _surviving_young_words[i] += surv_young_words[i];
ysr@777 2384 }
ysr@777 2385
ysr@777 2386 void
ysr@777 2387 G1CollectedHeap::cleanup_surviving_young_words() {
ysr@777 2388 guarantee( _surviving_young_words != NULL, "pre-condition" );
ysr@777 2389 FREE_C_HEAP_ARRAY(size_t, _surviving_young_words);
ysr@777 2390 _surviving_young_words = NULL;
ysr@777 2391 }
ysr@777 2392
ysr@777 2393 // </NEW PREDICTION>
ysr@777 2394
ysr@777 2395 void
ysr@777 2396 G1CollectedHeap::do_collection_pause_at_safepoint(HeapRegion* popular_region) {
ysr@777 2397 char verbose_str[128];
ysr@777 2398 sprintf(verbose_str, "GC pause ");
ysr@777 2399 if (popular_region != NULL)
ysr@777 2400 strcat(verbose_str, "(popular)");
ysr@777 2401 else if (g1_policy()->in_young_gc_mode()) {
ysr@777 2402 if (g1_policy()->full_young_gcs())
ysr@777 2403 strcat(verbose_str, "(young)");
ysr@777 2404 else
ysr@777 2405 strcat(verbose_str, "(partial)");
ysr@777 2406 }
ysr@777 2407 bool reset_should_initiate_conc_mark = false;
ysr@777 2408 if (popular_region != NULL && g1_policy()->should_initiate_conc_mark()) {
ysr@777 2409 // we currently do not allow an initial mark phase to be piggy-backed
ysr@777 2410 // on a popular pause
ysr@777 2411 reset_should_initiate_conc_mark = true;
ysr@777 2412 g1_policy()->unset_should_initiate_conc_mark();
ysr@777 2413 }
ysr@777 2414 if (g1_policy()->should_initiate_conc_mark())
ysr@777 2415 strcat(verbose_str, " (initial-mark)");
ysr@777 2416
ysr@777 2417 GCCauseSetter x(this, (popular_region == NULL ?
ysr@777 2418 GCCause::_g1_inc_collection_pause :
ysr@777 2419 GCCause::_g1_pop_region_collection_pause));
ysr@777 2420
ysr@777 2421 // if PrintGCDetails is on, we'll print long statistics information
ysr@777 2422 // in the collector policy code, so let's not print this as the output
ysr@777 2423 // is messy if we do.
ysr@777 2424 gclog_or_tty->date_stamp(PrintGC && PrintGCDateStamps);
ysr@777 2425 TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty);
ysr@777 2426 TraceTime t(verbose_str, PrintGC && !PrintGCDetails, true, gclog_or_tty);
ysr@777 2427
ysr@777 2428 ResourceMark rm;
ysr@777 2429 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
ysr@777 2430 assert(Thread::current() == VMThread::vm_thread(), "should be in vm thread");
ysr@777 2431 guarantee(!is_gc_active(), "collection is not reentrant");
ysr@777 2432 assert(regions_accounted_for(), "Region leakage!");
iveresov@788 2433
iveresov@788 2434 increment_gc_time_stamp();
ysr@777 2435
ysr@777 2436 if (g1_policy()->in_young_gc_mode()) {
ysr@777 2437 assert(check_young_list_well_formed(),
ysr@777 2438 "young list should be well formed");
ysr@777 2439 }
ysr@777 2440
ysr@777 2441 if (GC_locker::is_active()) {
ysr@777 2442 return; // GC is disabled (e.g. JNI GetXXXCritical operation)
ysr@777 2443 }
ysr@777 2444
ysr@777 2445 bool abandoned = false;
ysr@777 2446 { // Call to jvmpi::post_class_unload_events must occur outside of active GC
ysr@777 2447 IsGCActiveMark x;
ysr@777 2448
ysr@777 2449 gc_prologue(false);
ysr@777 2450 increment_total_collections();
ysr@777 2451
ysr@777 2452 #if G1_REM_SET_LOGGING
ysr@777 2453 gclog_or_tty->print_cr("\nJust chose CS, heap:");
ysr@777 2454 print();
ysr@777 2455 #endif
ysr@777 2456
ysr@777 2457 if (VerifyBeforeGC && total_collections() >= VerifyGCStartAt) {
ysr@777 2458 HandleMark hm; // Discard invalid handles created during verification
ysr@777 2459 prepare_for_verify();
ysr@777 2460 gclog_or_tty->print(" VerifyBeforeGC:");
ysr@777 2461 Universe::verify(false);
ysr@777 2462 }
ysr@777 2463
ysr@777 2464 COMPILER2_PRESENT(DerivedPointerTable::clear());
ysr@777 2465
ysr@777 2466 // We want to turn off ref discovere, if necessary, and turn it back on
ysr@777 2467 // on again later if we do.
ysr@777 2468 bool was_enabled = ref_processor()->discovery_enabled();
ysr@777 2469 if (was_enabled) ref_processor()->disable_discovery();
ysr@777 2470
ysr@777 2471 // Forget the current alloc region (we might even choose it to be part
ysr@777 2472 // of the collection set!).
ysr@777 2473 abandon_cur_alloc_region();
ysr@777 2474
ysr@777 2475 // The elapsed time induced by the start time below deliberately elides
ysr@777 2476 // the possible verification above.
ysr@777 2477 double start_time_sec = os::elapsedTime();
ysr@777 2478 GCOverheadReporter::recordSTWStart(start_time_sec);
ysr@777 2479 size_t start_used_bytes = used();
ysr@777 2480 if (!G1ConcMark) {
ysr@777 2481 do_sync_mark();
ysr@777 2482 }
ysr@777 2483
ysr@777 2484 g1_policy()->record_collection_pause_start(start_time_sec,
ysr@777 2485 start_used_bytes);
ysr@777 2486
ysr@777 2487 #if SCAN_ONLY_VERBOSE
ysr@777 2488 _young_list->print();
ysr@777 2489 #endif // SCAN_ONLY_VERBOSE
ysr@777 2490
ysr@777 2491 if (g1_policy()->should_initiate_conc_mark()) {
ysr@777 2492 concurrent_mark()->checkpointRootsInitialPre();
ysr@777 2493 }
ysr@777 2494 save_marks();
ysr@777 2495
ysr@777 2496 // We must do this before any possible evacuation that should propogate
ysr@777 2497 // marks, including evacuation of popular objects in a popular pause.
ysr@777 2498 if (mark_in_progress()) {
ysr@777 2499 double start_time_sec = os::elapsedTime();
ysr@777 2500
ysr@777 2501 _cm->drainAllSATBBuffers();
ysr@777 2502 double finish_mark_ms = (os::elapsedTime() - start_time_sec) * 1000.0;
ysr@777 2503 g1_policy()->record_satb_drain_time(finish_mark_ms);
ysr@777 2504
ysr@777 2505 }
ysr@777 2506 // Record the number of elements currently on the mark stack, so we
ysr@777 2507 // only iterate over these. (Since evacuation may add to the mark
ysr@777 2508 // stack, doing more exposes race conditions.) If no mark is in
ysr@777 2509 // progress, this will be zero.
ysr@777 2510 _cm->set_oops_do_bound();
ysr@777 2511
ysr@777 2512 assert(regions_accounted_for(), "Region leakage.");
ysr@777 2513
ysr@777 2514 bool abandoned = false;
ysr@777 2515
ysr@777 2516 if (mark_in_progress())
ysr@777 2517 concurrent_mark()->newCSet();
ysr@777 2518
ysr@777 2519 // Now choose the CS.
ysr@777 2520 if (popular_region == NULL) {
ysr@777 2521 g1_policy()->choose_collection_set();
ysr@777 2522 } else {
ysr@777 2523 // We may be evacuating a single region (for popularity).
ysr@777 2524 g1_policy()->record_popular_pause_preamble_start();
ysr@777 2525 popularity_pause_preamble(popular_region);
ysr@777 2526 g1_policy()->record_popular_pause_preamble_end();
ysr@777 2527 abandoned = (g1_policy()->collection_set() == NULL);
ysr@777 2528 // Now we allow more regions to be added (we have to collect
ysr@777 2529 // all popular regions).
ysr@777 2530 if (!abandoned) {
ysr@777 2531 g1_policy()->choose_collection_set(popular_region);
ysr@777 2532 }
ysr@777 2533 }
ysr@777 2534 // We may abandon a pause if we find no region that will fit in the MMU
ysr@777 2535 // pause.
ysr@777 2536 abandoned = (g1_policy()->collection_set() == NULL);
ysr@777 2537
ysr@777 2538 // Nothing to do if we were unable to choose a collection set.
ysr@777 2539 if (!abandoned) {
ysr@777 2540 #if G1_REM_SET_LOGGING
ysr@777 2541 gclog_or_tty->print_cr("\nAfter pause, heap:");
ysr@777 2542 print();
ysr@777 2543 #endif
ysr@777 2544
ysr@777 2545 setup_surviving_young_words();
ysr@777 2546
ysr@777 2547 // Set up the gc allocation regions.
ysr@777 2548 get_gc_alloc_regions();
ysr@777 2549
ysr@777 2550 // Actually do the work...
ysr@777 2551 evacuate_collection_set();
ysr@777 2552 free_collection_set(g1_policy()->collection_set());
ysr@777 2553 g1_policy()->clear_collection_set();
ysr@777 2554
ysr@777 2555 if (popular_region != NULL) {
ysr@777 2556 // We have to wait until now, because we don't want the region to
ysr@777 2557 // be rescheduled for pop-evac during RS update.
ysr@777 2558 popular_region->set_popular_pending(false);
ysr@777 2559 }
ysr@777 2560
ysr@777 2561 release_gc_alloc_regions();
ysr@777 2562
ysr@777 2563 cleanup_surviving_young_words();
ysr@777 2564
ysr@777 2565 if (g1_policy()->in_young_gc_mode()) {
ysr@777 2566 _young_list->reset_sampled_info();
ysr@777 2567 assert(check_young_list_empty(true),
ysr@777 2568 "young list should be empty");
ysr@777 2569
ysr@777 2570 #if SCAN_ONLY_VERBOSE
ysr@777 2571 _young_list->print();
ysr@777 2572 #endif // SCAN_ONLY_VERBOSE
ysr@777 2573
ysr@777 2574 _young_list->reset_auxilary_lists();
ysr@777 2575 }
ysr@777 2576 } else {
ysr@777 2577 COMPILER2_PRESENT(DerivedPointerTable::update_pointers());
ysr@777 2578 }
ysr@777 2579
ysr@777 2580 if (evacuation_failed()) {
ysr@777 2581 _summary_bytes_used = recalculate_used();
ysr@777 2582 } else {
ysr@777 2583 // The "used" of the the collection set have already been subtracted
ysr@777 2584 // when they were freed. Add in the bytes evacuated.
ysr@777 2585 _summary_bytes_used += g1_policy()->bytes_in_to_space();
ysr@777 2586 }
ysr@777 2587
ysr@777 2588 if (g1_policy()->in_young_gc_mode() &&
ysr@777 2589 g1_policy()->should_initiate_conc_mark()) {
ysr@777 2590 concurrent_mark()->checkpointRootsInitialPost();
ysr@777 2591 set_marking_started();
ysr@777 2592 doConcurrentMark();
ysr@777 2593 }
ysr@777 2594
ysr@777 2595 #if SCAN_ONLY_VERBOSE
ysr@777 2596 _young_list->print();
ysr@777 2597 #endif // SCAN_ONLY_VERBOSE
ysr@777 2598
ysr@777 2599 double end_time_sec = os::elapsedTime();
ysr@777 2600 g1_policy()->record_pause_time((end_time_sec - start_time_sec)*1000.0);
ysr@777 2601 GCOverheadReporter::recordSTWEnd(end_time_sec);
ysr@777 2602 g1_policy()->record_collection_pause_end(popular_region != NULL,
ysr@777 2603 abandoned);
ysr@777 2604
ysr@777 2605 assert(regions_accounted_for(), "Region leakage.");
ysr@777 2606
ysr@777 2607 if (VerifyAfterGC && total_collections() >= VerifyGCStartAt) {
ysr@777 2608 HandleMark hm; // Discard invalid handles created during verification
ysr@777 2609 gclog_or_tty->print(" VerifyAfterGC:");
ysr@777 2610 Universe::verify(false);
ysr@777 2611 }
ysr@777 2612
ysr@777 2613 if (was_enabled) ref_processor()->enable_discovery();
ysr@777 2614
ysr@777 2615 {
ysr@777 2616 size_t expand_bytes = g1_policy()->expansion_amount();
ysr@777 2617 if (expand_bytes > 0) {
ysr@777 2618 size_t bytes_before = capacity();
ysr@777 2619 expand(expand_bytes);
ysr@777 2620 }
ysr@777 2621 }
ysr@777 2622
ysr@777 2623 if (mark_in_progress())
ysr@777 2624 concurrent_mark()->update_g1_committed();
ysr@777 2625
ysr@777 2626 gc_epilogue(false);
ysr@777 2627 }
ysr@777 2628
ysr@777 2629 assert(verify_region_lists(), "Bad region lists.");
ysr@777 2630
ysr@777 2631 if (reset_should_initiate_conc_mark)
ysr@777 2632 g1_policy()->set_should_initiate_conc_mark();
ysr@777 2633
ysr@777 2634 if (ExitAfterGCNum > 0 && total_collections() == ExitAfterGCNum) {
ysr@777 2635 gclog_or_tty->print_cr("Stopping after GC #%d", ExitAfterGCNum);
ysr@777 2636 print_tracing_info();
ysr@777 2637 vm_exit(-1);
ysr@777 2638 }
ysr@777 2639 }
ysr@777 2640
ysr@777 2641 void G1CollectedHeap::set_gc_alloc_region(int purpose, HeapRegion* r) {
ysr@777 2642 assert(purpose >= 0 && purpose < GCAllocPurposeCount, "invalid purpose");
ysr@777 2643 HeapWord* original_top = NULL;
ysr@777 2644 if (r != NULL)
ysr@777 2645 original_top = r->top();
ysr@777 2646
ysr@777 2647 // We will want to record the used space in r as being there before gc.
ysr@777 2648 // One we install it as a GC alloc region it's eligible for allocation.
ysr@777 2649 // So record it now and use it later.
ysr@777 2650 size_t r_used = 0;
ysr@777 2651 if (r != NULL) {
ysr@777 2652 r_used = r->used();
ysr@777 2653
ysr@777 2654 if (ParallelGCThreads > 0) {
ysr@777 2655 // need to take the lock to guard against two threads calling
ysr@777 2656 // get_gc_alloc_region concurrently (very unlikely but...)
ysr@777 2657 MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag);
ysr@777 2658 r->save_marks();
ysr@777 2659 }
ysr@777 2660 }
ysr@777 2661 HeapRegion* old_alloc_region = _gc_alloc_regions[purpose];
ysr@777 2662 _gc_alloc_regions[purpose] = r;
ysr@777 2663 if (old_alloc_region != NULL) {
ysr@777 2664 // Replace aliases too.
ysr@777 2665 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) {
ysr@777 2666 if (_gc_alloc_regions[ap] == old_alloc_region) {
ysr@777 2667 _gc_alloc_regions[ap] = r;
ysr@777 2668 }
ysr@777 2669 }
ysr@777 2670 }
ysr@777 2671 if (r != NULL) {
ysr@777 2672 push_gc_alloc_region(r);
ysr@777 2673 if (mark_in_progress() && original_top != r->next_top_at_mark_start()) {
ysr@777 2674 // We are using a region as a GC alloc region after it has been used
ysr@777 2675 // as a mutator allocation region during the current marking cycle.
ysr@777 2676 // The mutator-allocated objects are currently implicitly marked, but
ysr@777 2677 // when we move hr->next_top_at_mark_start() forward at the the end
ysr@777 2678 // of the GC pause, they won't be. We therefore mark all objects in
ysr@777 2679 // the "gap". We do this object-by-object, since marking densely
ysr@777 2680 // does not currently work right with marking bitmap iteration. This
ysr@777 2681 // means we rely on TLAB filling at the start of pauses, and no
ysr@777 2682 // "resuscitation" of filled TLAB's. If we want to do this, we need
ysr@777 2683 // to fix the marking bitmap iteration.
ysr@777 2684 HeapWord* curhw = r->next_top_at_mark_start();
ysr@777 2685 HeapWord* t = original_top;
ysr@777 2686
ysr@777 2687 while (curhw < t) {
ysr@777 2688 oop cur = (oop)curhw;
ysr@777 2689 // We'll assume parallel for generality. This is rare code.
ysr@777 2690 concurrent_mark()->markAndGrayObjectIfNecessary(cur); // can't we just mark them?
ysr@777 2691 curhw = curhw + cur->size();
ysr@777 2692 }
ysr@777 2693 assert(curhw == t, "Should have parsed correctly.");
ysr@777 2694 }
ysr@777 2695 if (G1PolicyVerbose > 1) {
ysr@777 2696 gclog_or_tty->print("New alloc region ["PTR_FORMAT", "PTR_FORMAT", " PTR_FORMAT") "
ysr@777 2697 "for survivors:", r->bottom(), original_top, r->end());
ysr@777 2698 r->print();
ysr@777 2699 }
ysr@777 2700 g1_policy()->record_before_bytes(r_used);
ysr@777 2701 }
ysr@777 2702 }
ysr@777 2703
ysr@777 2704 void G1CollectedHeap::push_gc_alloc_region(HeapRegion* hr) {
ysr@777 2705 assert(Thread::current()->is_VM_thread() ||
ysr@777 2706 par_alloc_during_gc_lock()->owned_by_self(), "Precondition");
ysr@777 2707 assert(!hr->is_gc_alloc_region() && !hr->in_collection_set(),
ysr@777 2708 "Precondition.");
ysr@777 2709 hr->set_is_gc_alloc_region(true);
ysr@777 2710 hr->set_next_gc_alloc_region(_gc_alloc_region_list);
ysr@777 2711 _gc_alloc_region_list = hr;
ysr@777 2712 }
ysr@777 2713
ysr@777 2714 #ifdef G1_DEBUG
ysr@777 2715 class FindGCAllocRegion: public HeapRegionClosure {
ysr@777 2716 public:
ysr@777 2717 bool doHeapRegion(HeapRegion* r) {
ysr@777 2718 if (r->is_gc_alloc_region()) {
ysr@777 2719 gclog_or_tty->print_cr("Region %d ["PTR_FORMAT"...] is still a gc_alloc_region.",
ysr@777 2720 r->hrs_index(), r->bottom());
ysr@777 2721 }
ysr@777 2722 return false;
ysr@777 2723 }
ysr@777 2724 };
ysr@777 2725 #endif // G1_DEBUG
ysr@777 2726
ysr@777 2727 void G1CollectedHeap::forget_alloc_region_list() {
ysr@777 2728 assert(Thread::current()->is_VM_thread(), "Precondition");
ysr@777 2729 while (_gc_alloc_region_list != NULL) {
ysr@777 2730 HeapRegion* r = _gc_alloc_region_list;
ysr@777 2731 assert(r->is_gc_alloc_region(), "Invariant.");
ysr@777 2732 _gc_alloc_region_list = r->next_gc_alloc_region();
ysr@777 2733 r->set_next_gc_alloc_region(NULL);
ysr@777 2734 r->set_is_gc_alloc_region(false);
ysr@777 2735 if (r->is_empty()) {
ysr@777 2736 ++_free_regions;
ysr@777 2737 }
ysr@777 2738 }
ysr@777 2739 #ifdef G1_DEBUG
ysr@777 2740 FindGCAllocRegion fa;
ysr@777 2741 heap_region_iterate(&fa);
ysr@777 2742 #endif // G1_DEBUG
ysr@777 2743 }
ysr@777 2744
ysr@777 2745
ysr@777 2746 bool G1CollectedHeap::check_gc_alloc_regions() {
ysr@777 2747 // TODO: allocation regions check
ysr@777 2748 return true;
ysr@777 2749 }
ysr@777 2750
ysr@777 2751 void G1CollectedHeap::get_gc_alloc_regions() {
ysr@777 2752 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) {
ysr@777 2753 // Create new GC alloc regions.
ysr@777 2754 HeapRegion* alloc_region = _gc_alloc_regions[ap];
ysr@777 2755 // Clear this alloc region, so that in case it turns out to be
ysr@777 2756 // unacceptable, we end up with no allocation region, rather than a bad
ysr@777 2757 // one.
ysr@777 2758 _gc_alloc_regions[ap] = NULL;
ysr@777 2759 if (alloc_region == NULL || alloc_region->in_collection_set()) {
ysr@777 2760 // Can't re-use old one. Allocate a new one.
ysr@777 2761 alloc_region = newAllocRegionWithExpansion(ap, 0);
ysr@777 2762 }
ysr@777 2763 if (alloc_region != NULL) {
ysr@777 2764 set_gc_alloc_region(ap, alloc_region);
ysr@777 2765 }
ysr@777 2766 }
ysr@777 2767 // Set alternative regions for allocation purposes that have reached
ysr@777 2768 // thier limit.
ysr@777 2769 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) {
ysr@777 2770 GCAllocPurpose alt_purpose = g1_policy()->alternative_purpose(ap);
ysr@777 2771 if (_gc_alloc_regions[ap] == NULL && alt_purpose != ap) {
ysr@777 2772 _gc_alloc_regions[ap] = _gc_alloc_regions[alt_purpose];
ysr@777 2773 }
ysr@777 2774 }
ysr@777 2775 assert(check_gc_alloc_regions(), "alloc regions messed up");
ysr@777 2776 }
ysr@777 2777
ysr@777 2778 void G1CollectedHeap::release_gc_alloc_regions() {
ysr@777 2779 // We keep a separate list of all regions that have been alloc regions in
ysr@777 2780 // the current collection pause. Forget that now.
ysr@777 2781 forget_alloc_region_list();
ysr@777 2782
ysr@777 2783 // The current alloc regions contain objs that have survived
ysr@777 2784 // collection. Make them no longer GC alloc regions.
ysr@777 2785 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) {
ysr@777 2786 HeapRegion* r = _gc_alloc_regions[ap];
ysr@777 2787 if (r != NULL && r->is_empty()) {
ysr@777 2788 {
ysr@777 2789 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 2790 r->set_zero_fill_complete();
ysr@777 2791 put_free_region_on_list_locked(r);
ysr@777 2792 }
ysr@777 2793 }
ysr@777 2794 // set_gc_alloc_region will also NULLify all aliases to the region
ysr@777 2795 set_gc_alloc_region(ap, NULL);
ysr@777 2796 _gc_alloc_region_counts[ap] = 0;
ysr@777 2797 }
ysr@777 2798 }
ysr@777 2799
ysr@777 2800 void G1CollectedHeap::init_for_evac_failure(OopsInHeapRegionClosure* cl) {
ysr@777 2801 _drain_in_progress = false;
ysr@777 2802 set_evac_failure_closure(cl);
ysr@777 2803 _evac_failure_scan_stack = new (ResourceObj::C_HEAP) GrowableArray<oop>(40, true);
ysr@777 2804 }
ysr@777 2805
ysr@777 2806 void G1CollectedHeap::finalize_for_evac_failure() {
ysr@777 2807 assert(_evac_failure_scan_stack != NULL &&
ysr@777 2808 _evac_failure_scan_stack->length() == 0,
ysr@777 2809 "Postcondition");
ysr@777 2810 assert(!_drain_in_progress, "Postcondition");
ysr@777 2811 // Don't have to delete, since the scan stack is a resource object.
ysr@777 2812 _evac_failure_scan_stack = NULL;
ysr@777 2813 }
ysr@777 2814
ysr@777 2815
ysr@777 2816
ysr@777 2817 // *** Sequential G1 Evacuation
ysr@777 2818
ysr@777 2819 HeapWord* G1CollectedHeap::allocate_during_gc(GCAllocPurpose purpose, size_t word_size) {
ysr@777 2820 HeapRegion* alloc_region = _gc_alloc_regions[purpose];
ysr@777 2821 // let the caller handle alloc failure
ysr@777 2822 if (alloc_region == NULL) return NULL;
ysr@777 2823 assert(isHumongous(word_size) || !alloc_region->isHumongous(),
ysr@777 2824 "Either the object is humongous or the region isn't");
ysr@777 2825 HeapWord* block = alloc_region->allocate(word_size);
ysr@777 2826 if (block == NULL) {
ysr@777 2827 block = allocate_during_gc_slow(purpose, alloc_region, false, word_size);
ysr@777 2828 }
ysr@777 2829 return block;
ysr@777 2830 }
ysr@777 2831
ysr@777 2832 class G1IsAliveClosure: public BoolObjectClosure {
ysr@777 2833 G1CollectedHeap* _g1;
ysr@777 2834 public:
ysr@777 2835 G1IsAliveClosure(G1CollectedHeap* g1) : _g1(g1) {}
ysr@777 2836 void do_object(oop p) { assert(false, "Do not call."); }
ysr@777 2837 bool do_object_b(oop p) {
ysr@777 2838 // It is reachable if it is outside the collection set, or is inside
ysr@777 2839 // and forwarded.
ysr@777 2840
ysr@777 2841 #ifdef G1_DEBUG
ysr@777 2842 gclog_or_tty->print_cr("is alive "PTR_FORMAT" in CS %d forwarded %d overall %d",
ysr@777 2843 (void*) p, _g1->obj_in_cs(p), p->is_forwarded(),
ysr@777 2844 !_g1->obj_in_cs(p) || p->is_forwarded());
ysr@777 2845 #endif // G1_DEBUG
ysr@777 2846
ysr@777 2847 return !_g1->obj_in_cs(p) || p->is_forwarded();
ysr@777 2848 }
ysr@777 2849 };
ysr@777 2850
ysr@777 2851 class G1KeepAliveClosure: public OopClosure {
ysr@777 2852 G1CollectedHeap* _g1;
ysr@777 2853 public:
ysr@777 2854 G1KeepAliveClosure(G1CollectedHeap* g1) : _g1(g1) {}
ysr@777 2855 void do_oop(narrowOop* p) {
ysr@777 2856 guarantee(false, "NYI");
ysr@777 2857 }
ysr@777 2858 void do_oop(oop* p) {
ysr@777 2859 oop obj = *p;
ysr@777 2860 #ifdef G1_DEBUG
ysr@777 2861 if (PrintGC && Verbose) {
ysr@777 2862 gclog_or_tty->print_cr("keep alive *"PTR_FORMAT" = "PTR_FORMAT" "PTR_FORMAT,
ysr@777 2863 p, (void*) obj, (void*) *p);
ysr@777 2864 }
ysr@777 2865 #endif // G1_DEBUG
ysr@777 2866
ysr@777 2867 if (_g1->obj_in_cs(obj)) {
ysr@777 2868 assert( obj->is_forwarded(), "invariant" );
ysr@777 2869 *p = obj->forwardee();
ysr@777 2870
ysr@777 2871 #ifdef G1_DEBUG
ysr@777 2872 gclog_or_tty->print_cr(" in CSet: moved "PTR_FORMAT" -> "PTR_FORMAT,
ysr@777 2873 (void*) obj, (void*) *p);
ysr@777 2874 #endif // G1_DEBUG
ysr@777 2875 }
ysr@777 2876 }
ysr@777 2877 };
ysr@777 2878
ysr@777 2879 class RecreateRSetEntriesClosure: public OopClosure {
ysr@777 2880 private:
ysr@777 2881 G1CollectedHeap* _g1;
ysr@777 2882 G1RemSet* _g1_rem_set;
ysr@777 2883 HeapRegion* _from;
ysr@777 2884 public:
ysr@777 2885 RecreateRSetEntriesClosure(G1CollectedHeap* g1, HeapRegion* from) :
ysr@777 2886 _g1(g1), _g1_rem_set(g1->g1_rem_set()), _from(from)
ysr@777 2887 {}
ysr@777 2888
ysr@777 2889 void do_oop(narrowOop* p) {
ysr@777 2890 guarantee(false, "NYI");
ysr@777 2891 }
ysr@777 2892 void do_oop(oop* p) {
ysr@777 2893 assert(_from->is_in_reserved(p), "paranoia");
ysr@777 2894 if (*p != NULL) {
ysr@777 2895 _g1_rem_set->write_ref(_from, p);
ysr@777 2896 }
ysr@777 2897 }
ysr@777 2898 };
ysr@777 2899
ysr@777 2900 class RemoveSelfPointerClosure: public ObjectClosure {
ysr@777 2901 private:
ysr@777 2902 G1CollectedHeap* _g1;
ysr@777 2903 ConcurrentMark* _cm;
ysr@777 2904 HeapRegion* _hr;
ysr@777 2905 size_t _prev_marked_bytes;
ysr@777 2906 size_t _next_marked_bytes;
ysr@777 2907 public:
ysr@777 2908 RemoveSelfPointerClosure(G1CollectedHeap* g1, HeapRegion* hr) :
ysr@777 2909 _g1(g1), _cm(_g1->concurrent_mark()), _hr(hr),
ysr@777 2910 _prev_marked_bytes(0), _next_marked_bytes(0)
ysr@777 2911 {}
ysr@777 2912
ysr@777 2913 size_t prev_marked_bytes() { return _prev_marked_bytes; }
ysr@777 2914 size_t next_marked_bytes() { return _next_marked_bytes; }
ysr@777 2915
iveresov@787 2916 // The original idea here was to coalesce evacuated and dead objects.
iveresov@787 2917 // However that caused complications with the block offset table (BOT).
iveresov@787 2918 // In particular if there were two TLABs, one of them partially refined.
iveresov@787 2919 // |----- TLAB_1--------|----TLAB_2-~~~(partially refined part)~~~|
iveresov@787 2920 // The BOT entries of the unrefined part of TLAB_2 point to the start
iveresov@787 2921 // of TLAB_2. If the last object of the TLAB_1 and the first object
iveresov@787 2922 // of TLAB_2 are coalesced, then the cards of the unrefined part
iveresov@787 2923 // would point into middle of the filler object.
iveresov@787 2924 //
iveresov@787 2925 // The current approach is to not coalesce and leave the BOT contents intact.
iveresov@787 2926 void do_object(oop obj) {
iveresov@787 2927 if (obj->is_forwarded() && obj->forwardee() == obj) {
iveresov@787 2928 // The object failed to move.
iveresov@787 2929 assert(!_g1->is_obj_dead(obj), "We should not be preserving dead objs.");
iveresov@787 2930 _cm->markPrev(obj);
iveresov@787 2931 assert(_cm->isPrevMarked(obj), "Should be marked!");
iveresov@787 2932 _prev_marked_bytes += (obj->size() * HeapWordSize);
iveresov@787 2933 if (_g1->mark_in_progress() && !_g1->is_obj_ill(obj)) {
iveresov@787 2934 _cm->markAndGrayObjectIfNecessary(obj);
iveresov@787 2935 }
iveresov@787 2936 obj->set_mark(markOopDesc::prototype());
iveresov@787 2937 // While we were processing RSet buffers during the
iveresov@787 2938 // collection, we actually didn't scan any cards on the
iveresov@787 2939 // collection set, since we didn't want to update remebered
iveresov@787 2940 // sets with entries that point into the collection set, given
iveresov@787 2941 // that live objects fromthe collection set are about to move
iveresov@787 2942 // and such entries will be stale very soon. This change also
iveresov@787 2943 // dealt with a reliability issue which involved scanning a
iveresov@787 2944 // card in the collection set and coming across an array that
iveresov@787 2945 // was being chunked and looking malformed. The problem is
iveresov@787 2946 // that, if evacuation fails, we might have remembered set
iveresov@787 2947 // entries missing given that we skipped cards on the
iveresov@787 2948 // collection set. So, we'll recreate such entries now.
iveresov@787 2949 RecreateRSetEntriesClosure cl(_g1, _hr);
iveresov@787 2950 obj->oop_iterate(&cl);
iveresov@787 2951 assert(_cm->isPrevMarked(obj), "Should be marked!");
iveresov@787 2952 } else {
iveresov@787 2953 // The object has been either evacuated or is dead. Fill it with a
iveresov@787 2954 // dummy object.
iveresov@787 2955 MemRegion mr((HeapWord*)obj, obj->size());
ysr@777 2956 SharedHeap::fill_region_with_object(mr);
ysr@777 2957 _cm->clearRangeBothMaps(mr);
ysr@777 2958 }
ysr@777 2959 }
ysr@777 2960 };
ysr@777 2961
ysr@777 2962 void G1CollectedHeap::remove_self_forwarding_pointers() {
ysr@777 2963 HeapRegion* cur = g1_policy()->collection_set();
ysr@777 2964
ysr@777 2965 while (cur != NULL) {
ysr@777 2966 assert(g1_policy()->assertMarkedBytesDataOK(), "Should be!");
ysr@777 2967
ysr@777 2968 if (cur->evacuation_failed()) {
ysr@777 2969 RemoveSelfPointerClosure rspc(_g1h, cur);
ysr@777 2970 assert(cur->in_collection_set(), "bad CS");
ysr@777 2971 cur->object_iterate(&rspc);
ysr@777 2972
ysr@777 2973 // A number of manipulations to make the TAMS be the current top,
ysr@777 2974 // and the marked bytes be the ones observed in the iteration.
ysr@777 2975 if (_g1h->concurrent_mark()->at_least_one_mark_complete()) {
ysr@777 2976 // The comments below are the postconditions achieved by the
ysr@777 2977 // calls. Note especially the last such condition, which says that
ysr@777 2978 // the count of marked bytes has been properly restored.
ysr@777 2979 cur->note_start_of_marking(false);
ysr@777 2980 // _next_top_at_mark_start == top, _next_marked_bytes == 0
ysr@777 2981 cur->add_to_marked_bytes(rspc.prev_marked_bytes());
ysr@777 2982 // _next_marked_bytes == prev_marked_bytes.
ysr@777 2983 cur->note_end_of_marking();
ysr@777 2984 // _prev_top_at_mark_start == top(),
ysr@777 2985 // _prev_marked_bytes == prev_marked_bytes
ysr@777 2986 }
ysr@777 2987 // If there is no mark in progress, we modified the _next variables
ysr@777 2988 // above needlessly, but harmlessly.
ysr@777 2989 if (_g1h->mark_in_progress()) {
ysr@777 2990 cur->note_start_of_marking(false);
ysr@777 2991 // _next_top_at_mark_start == top, _next_marked_bytes == 0
ysr@777 2992 // _next_marked_bytes == next_marked_bytes.
ysr@777 2993 }
ysr@777 2994
ysr@777 2995 // Now make sure the region has the right index in the sorted array.
ysr@777 2996 g1_policy()->note_change_in_marked_bytes(cur);
ysr@777 2997 }
ysr@777 2998 cur = cur->next_in_collection_set();
ysr@777 2999 }
ysr@777 3000 assert(g1_policy()->assertMarkedBytesDataOK(), "Should be!");
ysr@777 3001
ysr@777 3002 // Now restore saved marks, if any.
ysr@777 3003 if (_objs_with_preserved_marks != NULL) {
ysr@777 3004 assert(_preserved_marks_of_objs != NULL, "Both or none.");
ysr@777 3005 assert(_objs_with_preserved_marks->length() ==
ysr@777 3006 _preserved_marks_of_objs->length(), "Both or none.");
ysr@777 3007 guarantee(_objs_with_preserved_marks->length() ==
ysr@777 3008 _preserved_marks_of_objs->length(), "Both or none.");
ysr@777 3009 for (int i = 0; i < _objs_with_preserved_marks->length(); i++) {
ysr@777 3010 oop obj = _objs_with_preserved_marks->at(i);
ysr@777 3011 markOop m = _preserved_marks_of_objs->at(i);
ysr@777 3012 obj->set_mark(m);
ysr@777 3013 }
ysr@777 3014 // Delete the preserved marks growable arrays (allocated on the C heap).
ysr@777 3015 delete _objs_with_preserved_marks;
ysr@777 3016 delete _preserved_marks_of_objs;
ysr@777 3017 _objs_with_preserved_marks = NULL;
ysr@777 3018 _preserved_marks_of_objs = NULL;
ysr@777 3019 }
ysr@777 3020 }
ysr@777 3021
ysr@777 3022 void G1CollectedHeap::push_on_evac_failure_scan_stack(oop obj) {
ysr@777 3023 _evac_failure_scan_stack->push(obj);
ysr@777 3024 }
ysr@777 3025
ysr@777 3026 void G1CollectedHeap::drain_evac_failure_scan_stack() {
ysr@777 3027 assert(_evac_failure_scan_stack != NULL, "precondition");
ysr@777 3028
ysr@777 3029 while (_evac_failure_scan_stack->length() > 0) {
ysr@777 3030 oop obj = _evac_failure_scan_stack->pop();
ysr@777 3031 _evac_failure_closure->set_region(heap_region_containing(obj));
ysr@777 3032 obj->oop_iterate_backwards(_evac_failure_closure);
ysr@777 3033 }
ysr@777 3034 }
ysr@777 3035
ysr@777 3036 void G1CollectedHeap::handle_evacuation_failure(oop old) {
ysr@777 3037 markOop m = old->mark();
ysr@777 3038 // forward to self
ysr@777 3039 assert(!old->is_forwarded(), "precondition");
ysr@777 3040
ysr@777 3041 old->forward_to(old);
ysr@777 3042 handle_evacuation_failure_common(old, m);
ysr@777 3043 }
ysr@777 3044
ysr@777 3045 oop
ysr@777 3046 G1CollectedHeap::handle_evacuation_failure_par(OopsInHeapRegionClosure* cl,
ysr@777 3047 oop old) {
ysr@777 3048 markOop m = old->mark();
ysr@777 3049 oop forward_ptr = old->forward_to_atomic(old);
ysr@777 3050 if (forward_ptr == NULL) {
ysr@777 3051 // Forward-to-self succeeded.
ysr@777 3052 if (_evac_failure_closure != cl) {
ysr@777 3053 MutexLockerEx x(EvacFailureStack_lock, Mutex::_no_safepoint_check_flag);
ysr@777 3054 assert(!_drain_in_progress,
ysr@777 3055 "Should only be true while someone holds the lock.");
ysr@777 3056 // Set the global evac-failure closure to the current thread's.
ysr@777 3057 assert(_evac_failure_closure == NULL, "Or locking has failed.");
ysr@777 3058 set_evac_failure_closure(cl);
ysr@777 3059 // Now do the common part.
ysr@777 3060 handle_evacuation_failure_common(old, m);
ysr@777 3061 // Reset to NULL.
ysr@777 3062 set_evac_failure_closure(NULL);
ysr@777 3063 } else {
ysr@777 3064 // The lock is already held, and this is recursive.
ysr@777 3065 assert(_drain_in_progress, "This should only be the recursive case.");
ysr@777 3066 handle_evacuation_failure_common(old, m);
ysr@777 3067 }
ysr@777 3068 return old;
ysr@777 3069 } else {
ysr@777 3070 // Someone else had a place to copy it.
ysr@777 3071 return forward_ptr;
ysr@777 3072 }
ysr@777 3073 }
ysr@777 3074
ysr@777 3075 void G1CollectedHeap::handle_evacuation_failure_common(oop old, markOop m) {
ysr@777 3076 set_evacuation_failed(true);
ysr@777 3077
ysr@777 3078 preserve_mark_if_necessary(old, m);
ysr@777 3079
ysr@777 3080 HeapRegion* r = heap_region_containing(old);
ysr@777 3081 if (!r->evacuation_failed()) {
ysr@777 3082 r->set_evacuation_failed(true);
ysr@777 3083 if (G1TraceRegions) {
ysr@777 3084 gclog_or_tty->print("evacuation failed in heap region "PTR_FORMAT" "
ysr@777 3085 "["PTR_FORMAT","PTR_FORMAT")\n",
ysr@777 3086 r, r->bottom(), r->end());
ysr@777 3087 }
ysr@777 3088 }
ysr@777 3089
ysr@777 3090 push_on_evac_failure_scan_stack(old);
ysr@777 3091
ysr@777 3092 if (!_drain_in_progress) {
ysr@777 3093 // prevent recursion in copy_to_survivor_space()
ysr@777 3094 _drain_in_progress = true;
ysr@777 3095 drain_evac_failure_scan_stack();
ysr@777 3096 _drain_in_progress = false;
ysr@777 3097 }
ysr@777 3098 }
ysr@777 3099
ysr@777 3100 void G1CollectedHeap::preserve_mark_if_necessary(oop obj, markOop m) {
ysr@777 3101 if (m != markOopDesc::prototype()) {
ysr@777 3102 if (_objs_with_preserved_marks == NULL) {
ysr@777 3103 assert(_preserved_marks_of_objs == NULL, "Both or none.");
ysr@777 3104 _objs_with_preserved_marks =
ysr@777 3105 new (ResourceObj::C_HEAP) GrowableArray<oop>(40, true);
ysr@777 3106 _preserved_marks_of_objs =
ysr@777 3107 new (ResourceObj::C_HEAP) GrowableArray<markOop>(40, true);
ysr@777 3108 }
ysr@777 3109 _objs_with_preserved_marks->push(obj);
ysr@777 3110 _preserved_marks_of_objs->push(m);
ysr@777 3111 }
ysr@777 3112 }
ysr@777 3113
ysr@777 3114 // *** Parallel G1 Evacuation
ysr@777 3115
ysr@777 3116 HeapWord* G1CollectedHeap::par_allocate_during_gc(GCAllocPurpose purpose,
ysr@777 3117 size_t word_size) {
ysr@777 3118 HeapRegion* alloc_region = _gc_alloc_regions[purpose];
ysr@777 3119 // let the caller handle alloc failure
ysr@777 3120 if (alloc_region == NULL) return NULL;
ysr@777 3121
ysr@777 3122 HeapWord* block = alloc_region->par_allocate(word_size);
ysr@777 3123 if (block == NULL) {
ysr@777 3124 MutexLockerEx x(par_alloc_during_gc_lock(),
ysr@777 3125 Mutex::_no_safepoint_check_flag);
ysr@777 3126 block = allocate_during_gc_slow(purpose, alloc_region, true, word_size);
ysr@777 3127 }
ysr@777 3128 return block;
ysr@777 3129 }
ysr@777 3130
ysr@777 3131 HeapWord*
ysr@777 3132 G1CollectedHeap::allocate_during_gc_slow(GCAllocPurpose purpose,
ysr@777 3133 HeapRegion* alloc_region,
ysr@777 3134 bool par,
ysr@777 3135 size_t word_size) {
ysr@777 3136 HeapWord* block = NULL;
ysr@777 3137 // In the parallel case, a previous thread to obtain the lock may have
ysr@777 3138 // already assigned a new gc_alloc_region.
ysr@777 3139 if (alloc_region != _gc_alloc_regions[purpose]) {
ysr@777 3140 assert(par, "But should only happen in parallel case.");
ysr@777 3141 alloc_region = _gc_alloc_regions[purpose];
ysr@777 3142 if (alloc_region == NULL) return NULL;
ysr@777 3143 block = alloc_region->par_allocate(word_size);
ysr@777 3144 if (block != NULL) return block;
ysr@777 3145 // Otherwise, continue; this new region is empty, too.
ysr@777 3146 }
ysr@777 3147 assert(alloc_region != NULL, "We better have an allocation region");
ysr@777 3148 // Another thread might have obtained alloc_region for the given
ysr@777 3149 // purpose, and might be attempting to allocate in it, and might
ysr@777 3150 // succeed. Therefore, we can't do the "finalization" stuff on the
ysr@777 3151 // region below until we're sure the last allocation has happened.
ysr@777 3152 // We ensure this by allocating the remaining space with a garbage
ysr@777 3153 // object.
ysr@777 3154 if (par) par_allocate_remaining_space(alloc_region);
ysr@777 3155 // Now we can do the post-GC stuff on the region.
ysr@777 3156 alloc_region->note_end_of_copying();
ysr@777 3157 g1_policy()->record_after_bytes(alloc_region->used());
ysr@777 3158
ysr@777 3159 if (_gc_alloc_region_counts[purpose] >= g1_policy()->max_regions(purpose)) {
ysr@777 3160 // Cannot allocate more regions for the given purpose.
ysr@777 3161 GCAllocPurpose alt_purpose = g1_policy()->alternative_purpose(purpose);
ysr@777 3162 // Is there an alternative?
ysr@777 3163 if (purpose != alt_purpose) {
ysr@777 3164 HeapRegion* alt_region = _gc_alloc_regions[alt_purpose];
ysr@777 3165 // Has not the alternative region been aliased?
ysr@777 3166 if (alloc_region != alt_region) {
ysr@777 3167 // Try to allocate in the alternative region.
ysr@777 3168 if (par) {
ysr@777 3169 block = alt_region->par_allocate(word_size);
ysr@777 3170 } else {
ysr@777 3171 block = alt_region->allocate(word_size);
ysr@777 3172 }
ysr@777 3173 // Make an alias.
ysr@777 3174 _gc_alloc_regions[purpose] = _gc_alloc_regions[alt_purpose];
ysr@777 3175 }
ysr@777 3176 if (block != NULL) {
ysr@777 3177 return block;
ysr@777 3178 }
ysr@777 3179 // Both the allocation region and the alternative one are full
ysr@777 3180 // and aliased, replace them with a new allocation region.
ysr@777 3181 purpose = alt_purpose;
ysr@777 3182 } else {
ysr@777 3183 set_gc_alloc_region(purpose, NULL);
ysr@777 3184 return NULL;
ysr@777 3185 }
ysr@777 3186 }
ysr@777 3187
ysr@777 3188 // Now allocate a new region for allocation.
ysr@777 3189 alloc_region = newAllocRegionWithExpansion(purpose, word_size, false /*zero_filled*/);
ysr@777 3190
ysr@777 3191 // let the caller handle alloc failure
ysr@777 3192 if (alloc_region != NULL) {
ysr@777 3193
ysr@777 3194 assert(check_gc_alloc_regions(), "alloc regions messed up");
ysr@777 3195 assert(alloc_region->saved_mark_at_top(),
ysr@777 3196 "Mark should have been saved already.");
ysr@777 3197 // We used to assert that the region was zero-filled here, but no
ysr@777 3198 // longer.
ysr@777 3199
ysr@777 3200 // This must be done last: once it's installed, other regions may
ysr@777 3201 // allocate in it (without holding the lock.)
ysr@777 3202 set_gc_alloc_region(purpose, alloc_region);
ysr@777 3203
ysr@777 3204 if (par) {
ysr@777 3205 block = alloc_region->par_allocate(word_size);
ysr@777 3206 } else {
ysr@777 3207 block = alloc_region->allocate(word_size);
ysr@777 3208 }
ysr@777 3209 // Caller handles alloc failure.
ysr@777 3210 } else {
ysr@777 3211 // This sets other apis using the same old alloc region to NULL, also.
ysr@777 3212 set_gc_alloc_region(purpose, NULL);
ysr@777 3213 }
ysr@777 3214 return block; // May be NULL.
ysr@777 3215 }
ysr@777 3216
ysr@777 3217 void G1CollectedHeap::par_allocate_remaining_space(HeapRegion* r) {
ysr@777 3218 HeapWord* block = NULL;
ysr@777 3219 size_t free_words;
ysr@777 3220 do {
ysr@777 3221 free_words = r->free()/HeapWordSize;
ysr@777 3222 // If there's too little space, no one can allocate, so we're done.
ysr@777 3223 if (free_words < (size_t)oopDesc::header_size()) return;
ysr@777 3224 // Otherwise, try to claim it.
ysr@777 3225 block = r->par_allocate(free_words);
ysr@777 3226 } while (block == NULL);
ysr@777 3227 SharedHeap::fill_region_with_object(MemRegion(block, free_words));
ysr@777 3228 }
ysr@777 3229
ysr@777 3230 #define use_local_bitmaps 1
ysr@777 3231 #define verify_local_bitmaps 0
ysr@777 3232
ysr@777 3233 #ifndef PRODUCT
ysr@777 3234
ysr@777 3235 class GCLabBitMap;
ysr@777 3236 class GCLabBitMapClosure: public BitMapClosure {
ysr@777 3237 private:
ysr@777 3238 ConcurrentMark* _cm;
ysr@777 3239 GCLabBitMap* _bitmap;
ysr@777 3240
ysr@777 3241 public:
ysr@777 3242 GCLabBitMapClosure(ConcurrentMark* cm,
ysr@777 3243 GCLabBitMap* bitmap) {
ysr@777 3244 _cm = cm;
ysr@777 3245 _bitmap = bitmap;
ysr@777 3246 }
ysr@777 3247
ysr@777 3248 virtual bool do_bit(size_t offset);
ysr@777 3249 };
ysr@777 3250
ysr@777 3251 #endif // PRODUCT
ysr@777 3252
ysr@777 3253 #define oop_buffer_length 256
ysr@777 3254
ysr@777 3255 class GCLabBitMap: public BitMap {
ysr@777 3256 private:
ysr@777 3257 ConcurrentMark* _cm;
ysr@777 3258
ysr@777 3259 int _shifter;
ysr@777 3260 size_t _bitmap_word_covers_words;
ysr@777 3261
ysr@777 3262 // beginning of the heap
ysr@777 3263 HeapWord* _heap_start;
ysr@777 3264
ysr@777 3265 // this is the actual start of the GCLab
ysr@777 3266 HeapWord* _real_start_word;
ysr@777 3267
ysr@777 3268 // this is the actual end of the GCLab
ysr@777 3269 HeapWord* _real_end_word;
ysr@777 3270
ysr@777 3271 // this is the first word, possibly located before the actual start
ysr@777 3272 // of the GCLab, that corresponds to the first bit of the bitmap
ysr@777 3273 HeapWord* _start_word;
ysr@777 3274
ysr@777 3275 // size of a GCLab in words
ysr@777 3276 size_t _gclab_word_size;
ysr@777 3277
ysr@777 3278 static int shifter() {
ysr@777 3279 return MinObjAlignment - 1;
ysr@777 3280 }
ysr@777 3281
ysr@777 3282 // how many heap words does a single bitmap word corresponds to?
ysr@777 3283 static size_t bitmap_word_covers_words() {
ysr@777 3284 return BitsPerWord << shifter();
ysr@777 3285 }
ysr@777 3286
ysr@777 3287 static size_t gclab_word_size() {
ysr@777 3288 return ParallelGCG1AllocBufferSize / HeapWordSize;
ysr@777 3289 }
ysr@777 3290
ysr@777 3291 static size_t bitmap_size_in_bits() {
ysr@777 3292 size_t bits_in_bitmap = gclab_word_size() >> shifter();
ysr@777 3293 // We are going to ensure that the beginning of a word in this
ysr@777 3294 // bitmap also corresponds to the beginning of a word in the
ysr@777 3295 // global marking bitmap. To handle the case where a GCLab
ysr@777 3296 // starts from the middle of the bitmap, we need to add enough
ysr@777 3297 // space (i.e. up to a bitmap word) to ensure that we have
ysr@777 3298 // enough bits in the bitmap.
ysr@777 3299 return bits_in_bitmap + BitsPerWord - 1;
ysr@777 3300 }
ysr@777 3301 public:
ysr@777 3302 GCLabBitMap(HeapWord* heap_start)
ysr@777 3303 : BitMap(bitmap_size_in_bits()),
ysr@777 3304 _cm(G1CollectedHeap::heap()->concurrent_mark()),
ysr@777 3305 _shifter(shifter()),
ysr@777 3306 _bitmap_word_covers_words(bitmap_word_covers_words()),
ysr@777 3307 _heap_start(heap_start),
ysr@777 3308 _gclab_word_size(gclab_word_size()),
ysr@777 3309 _real_start_word(NULL),
ysr@777 3310 _real_end_word(NULL),
ysr@777 3311 _start_word(NULL)
ysr@777 3312 {
ysr@777 3313 guarantee( size_in_words() >= bitmap_size_in_words(),
ysr@777 3314 "just making sure");
ysr@777 3315 }
ysr@777 3316
ysr@777 3317 inline unsigned heapWordToOffset(HeapWord* addr) {
ysr@777 3318 unsigned offset = (unsigned) pointer_delta(addr, _start_word) >> _shifter;
ysr@777 3319 assert(offset < size(), "offset should be within bounds");
ysr@777 3320 return offset;
ysr@777 3321 }
ysr@777 3322
ysr@777 3323 inline HeapWord* offsetToHeapWord(size_t offset) {
ysr@777 3324 HeapWord* addr = _start_word + (offset << _shifter);
ysr@777 3325 assert(_real_start_word <= addr && addr < _real_end_word, "invariant");
ysr@777 3326 return addr;
ysr@777 3327 }
ysr@777 3328
ysr@777 3329 bool fields_well_formed() {
ysr@777 3330 bool ret1 = (_real_start_word == NULL) &&
ysr@777 3331 (_real_end_word == NULL) &&
ysr@777 3332 (_start_word == NULL);
ysr@777 3333 if (ret1)
ysr@777 3334 return true;
ysr@777 3335
ysr@777 3336 bool ret2 = _real_start_word >= _start_word &&
ysr@777 3337 _start_word < _real_end_word &&
ysr@777 3338 (_real_start_word + _gclab_word_size) == _real_end_word &&
ysr@777 3339 (_start_word + _gclab_word_size + _bitmap_word_covers_words)
ysr@777 3340 > _real_end_word;
ysr@777 3341 return ret2;
ysr@777 3342 }
ysr@777 3343
ysr@777 3344 inline bool mark(HeapWord* addr) {
ysr@777 3345 guarantee(use_local_bitmaps, "invariant");
ysr@777 3346 assert(fields_well_formed(), "invariant");
ysr@777 3347
ysr@777 3348 if (addr >= _real_start_word && addr < _real_end_word) {
ysr@777 3349 assert(!isMarked(addr), "should not have already been marked");
ysr@777 3350
ysr@777 3351 // first mark it on the bitmap
ysr@777 3352 at_put(heapWordToOffset(addr), true);
ysr@777 3353
ysr@777 3354 return true;
ysr@777 3355 } else {
ysr@777 3356 return false;
ysr@777 3357 }
ysr@777 3358 }
ysr@777 3359
ysr@777 3360 inline bool isMarked(HeapWord* addr) {
ysr@777 3361 guarantee(use_local_bitmaps, "invariant");
ysr@777 3362 assert(fields_well_formed(), "invariant");
ysr@777 3363
ysr@777 3364 return at(heapWordToOffset(addr));
ysr@777 3365 }
ysr@777 3366
ysr@777 3367 void set_buffer(HeapWord* start) {
ysr@777 3368 guarantee(use_local_bitmaps, "invariant");
ysr@777 3369 clear();
ysr@777 3370
ysr@777 3371 assert(start != NULL, "invariant");
ysr@777 3372 _real_start_word = start;
ysr@777 3373 _real_end_word = start + _gclab_word_size;
ysr@777 3374
ysr@777 3375 size_t diff =
ysr@777 3376 pointer_delta(start, _heap_start) % _bitmap_word_covers_words;
ysr@777 3377 _start_word = start - diff;
ysr@777 3378
ysr@777 3379 assert(fields_well_formed(), "invariant");
ysr@777 3380 }
ysr@777 3381
ysr@777 3382 #ifndef PRODUCT
ysr@777 3383 void verify() {
ysr@777 3384 // verify that the marks have been propagated
ysr@777 3385 GCLabBitMapClosure cl(_cm, this);
ysr@777 3386 iterate(&cl);
ysr@777 3387 }
ysr@777 3388 #endif // PRODUCT
ysr@777 3389
ysr@777 3390 void retire() {
ysr@777 3391 guarantee(use_local_bitmaps, "invariant");
ysr@777 3392 assert(fields_well_formed(), "invariant");
ysr@777 3393
ysr@777 3394 if (_start_word != NULL) {
ysr@777 3395 CMBitMap* mark_bitmap = _cm->nextMarkBitMap();
ysr@777 3396
ysr@777 3397 // this means that the bitmap was set up for the GCLab
ysr@777 3398 assert(_real_start_word != NULL && _real_end_word != NULL, "invariant");
ysr@777 3399
ysr@777 3400 mark_bitmap->mostly_disjoint_range_union(this,
ysr@777 3401 0, // always start from the start of the bitmap
ysr@777 3402 _start_word,
ysr@777 3403 size_in_words());
ysr@777 3404 _cm->grayRegionIfNecessary(MemRegion(_real_start_word, _real_end_word));
ysr@777 3405
ysr@777 3406 #ifndef PRODUCT
ysr@777 3407 if (use_local_bitmaps && verify_local_bitmaps)
ysr@777 3408 verify();
ysr@777 3409 #endif // PRODUCT
ysr@777 3410 } else {
ysr@777 3411 assert(_real_start_word == NULL && _real_end_word == NULL, "invariant");
ysr@777 3412 }
ysr@777 3413 }
ysr@777 3414
ysr@777 3415 static size_t bitmap_size_in_words() {
ysr@777 3416 return (bitmap_size_in_bits() + BitsPerWord - 1) / BitsPerWord;
ysr@777 3417 }
ysr@777 3418 };
ysr@777 3419
ysr@777 3420 #ifndef PRODUCT
ysr@777 3421
ysr@777 3422 bool GCLabBitMapClosure::do_bit(size_t offset) {
ysr@777 3423 HeapWord* addr = _bitmap->offsetToHeapWord(offset);
ysr@777 3424 guarantee(_cm->isMarked(oop(addr)), "it should be!");
ysr@777 3425 return true;
ysr@777 3426 }
ysr@777 3427
ysr@777 3428 #endif // PRODUCT
ysr@777 3429
ysr@777 3430 class G1ParGCAllocBuffer: public ParGCAllocBuffer {
ysr@777 3431 private:
ysr@777 3432 bool _retired;
ysr@777 3433 bool _during_marking;
ysr@777 3434 GCLabBitMap _bitmap;
ysr@777 3435
ysr@777 3436 public:
ysr@777 3437 G1ParGCAllocBuffer() :
ysr@777 3438 ParGCAllocBuffer(ParallelGCG1AllocBufferSize / HeapWordSize),
ysr@777 3439 _during_marking(G1CollectedHeap::heap()->mark_in_progress()),
ysr@777 3440 _bitmap(G1CollectedHeap::heap()->reserved_region().start()),
ysr@777 3441 _retired(false)
ysr@777 3442 { }
ysr@777 3443
ysr@777 3444 inline bool mark(HeapWord* addr) {
ysr@777 3445 guarantee(use_local_bitmaps, "invariant");
ysr@777 3446 assert(_during_marking, "invariant");
ysr@777 3447 return _bitmap.mark(addr);
ysr@777 3448 }
ysr@777 3449
ysr@777 3450 inline void set_buf(HeapWord* buf) {
ysr@777 3451 if (use_local_bitmaps && _during_marking)
ysr@777 3452 _bitmap.set_buffer(buf);
ysr@777 3453 ParGCAllocBuffer::set_buf(buf);
ysr@777 3454 _retired = false;
ysr@777 3455 }
ysr@777 3456
ysr@777 3457 inline void retire(bool end_of_gc, bool retain) {
ysr@777 3458 if (_retired)
ysr@777 3459 return;
ysr@777 3460 if (use_local_bitmaps && _during_marking) {
ysr@777 3461 _bitmap.retire();
ysr@777 3462 }
ysr@777 3463 ParGCAllocBuffer::retire(end_of_gc, retain);
ysr@777 3464 _retired = true;
ysr@777 3465 }
ysr@777 3466 };
ysr@777 3467
ysr@777 3468
ysr@777 3469 class G1ParScanThreadState : public StackObj {
ysr@777 3470 protected:
ysr@777 3471 G1CollectedHeap* _g1h;
ysr@777 3472 RefToScanQueue* _refs;
ysr@777 3473
ysr@777 3474 typedef GrowableArray<oop*> OverflowQueue;
ysr@777 3475 OverflowQueue* _overflowed_refs;
ysr@777 3476
ysr@777 3477 G1ParGCAllocBuffer _alloc_buffers[GCAllocPurposeCount];
ysr@777 3478
ysr@777 3479 size_t _alloc_buffer_waste;
ysr@777 3480 size_t _undo_waste;
ysr@777 3481
ysr@777 3482 OopsInHeapRegionClosure* _evac_failure_cl;
ysr@777 3483 G1ParScanHeapEvacClosure* _evac_cl;
ysr@777 3484 G1ParScanPartialArrayClosure* _partial_scan_cl;
ysr@777 3485
ysr@777 3486 int _hash_seed;
ysr@777 3487 int _queue_num;
ysr@777 3488
ysr@777 3489 int _term_attempts;
ysr@777 3490 #if G1_DETAILED_STATS
ysr@777 3491 int _pushes, _pops, _steals, _steal_attempts;
ysr@777 3492 int _overflow_pushes;
ysr@777 3493 #endif
ysr@777 3494
ysr@777 3495 double _start;
ysr@777 3496 double _start_strong_roots;
ysr@777 3497 double _strong_roots_time;
ysr@777 3498 double _start_term;
ysr@777 3499 double _term_time;
ysr@777 3500
ysr@777 3501 // Map from young-age-index (0 == not young, 1 is youngest) to
ysr@777 3502 // surviving words. base is what we get back from the malloc call
ysr@777 3503 size_t* _surviving_young_words_base;
ysr@777 3504 // this points into the array, as we use the first few entries for padding
ysr@777 3505 size_t* _surviving_young_words;
ysr@777 3506
ysr@777 3507 #define PADDING_ELEM_NUM (64 / sizeof(size_t))
ysr@777 3508
ysr@777 3509 void add_to_alloc_buffer_waste(size_t waste) { _alloc_buffer_waste += waste; }
ysr@777 3510
ysr@777 3511 void add_to_undo_waste(size_t waste) { _undo_waste += waste; }
ysr@777 3512
ysr@777 3513 public:
ysr@777 3514 G1ParScanThreadState(G1CollectedHeap* g1h, int queue_num)
ysr@777 3515 : _g1h(g1h),
ysr@777 3516 _refs(g1h->task_queue(queue_num)),
ysr@777 3517 _hash_seed(17), _queue_num(queue_num),
ysr@777 3518 _term_attempts(0),
ysr@777 3519 #if G1_DETAILED_STATS
ysr@777 3520 _pushes(0), _pops(0), _steals(0),
ysr@777 3521 _steal_attempts(0), _overflow_pushes(0),
ysr@777 3522 #endif
ysr@777 3523 _strong_roots_time(0), _term_time(0),
ysr@777 3524 _alloc_buffer_waste(0), _undo_waste(0)
ysr@777 3525 {
ysr@777 3526 // we allocate G1YoungSurvRateNumRegions plus one entries, since
ysr@777 3527 // we "sacrifice" entry 0 to keep track of surviving bytes for
ysr@777 3528 // non-young regions (where the age is -1)
ysr@777 3529 // We also add a few elements at the beginning and at the end in
ysr@777 3530 // an attempt to eliminate cache contention
ysr@777 3531 size_t real_length = 1 + _g1h->g1_policy()->young_cset_length();
ysr@777 3532 size_t array_length = PADDING_ELEM_NUM +
ysr@777 3533 real_length +
ysr@777 3534 PADDING_ELEM_NUM;
ysr@777 3535 _surviving_young_words_base = NEW_C_HEAP_ARRAY(size_t, array_length);
ysr@777 3536 if (_surviving_young_words_base == NULL)
ysr@777 3537 vm_exit_out_of_memory(array_length * sizeof(size_t),
ysr@777 3538 "Not enough space for young surv histo.");
ysr@777 3539 _surviving_young_words = _surviving_young_words_base + PADDING_ELEM_NUM;
ysr@777 3540 memset(_surviving_young_words, 0, real_length * sizeof(size_t));
ysr@777 3541
ysr@777 3542 _overflowed_refs = new OverflowQueue(10);
ysr@777 3543
ysr@777 3544 _start = os::elapsedTime();
ysr@777 3545 }
ysr@777 3546
ysr@777 3547 ~G1ParScanThreadState() {
ysr@777 3548 FREE_C_HEAP_ARRAY(size_t, _surviving_young_words_base);
ysr@777 3549 }
ysr@777 3550
ysr@777 3551 RefToScanQueue* refs() { return _refs; }
ysr@777 3552 OverflowQueue* overflowed_refs() { return _overflowed_refs; }
ysr@777 3553
ysr@777 3554 inline G1ParGCAllocBuffer* alloc_buffer(GCAllocPurpose purpose) {
ysr@777 3555 return &_alloc_buffers[purpose];
ysr@777 3556 }
ysr@777 3557
ysr@777 3558 size_t alloc_buffer_waste() { return _alloc_buffer_waste; }
ysr@777 3559 size_t undo_waste() { return _undo_waste; }
ysr@777 3560
ysr@777 3561 void push_on_queue(oop* ref) {
ysr@777 3562 if (!refs()->push(ref)) {
ysr@777 3563 overflowed_refs()->push(ref);
ysr@777 3564 IF_G1_DETAILED_STATS(note_overflow_push());
ysr@777 3565 } else {
ysr@777 3566 IF_G1_DETAILED_STATS(note_push());
ysr@777 3567 }
ysr@777 3568 }
ysr@777 3569
ysr@777 3570 void pop_from_queue(oop*& ref) {
ysr@777 3571 if (!refs()->pop_local(ref)) {
ysr@777 3572 ref = NULL;
ysr@777 3573 } else {
ysr@777 3574 IF_G1_DETAILED_STATS(note_pop());
ysr@777 3575 }
ysr@777 3576 }
ysr@777 3577
ysr@777 3578 void pop_from_overflow_queue(oop*& ref) {
ysr@777 3579 ref = overflowed_refs()->pop();
ysr@777 3580 }
ysr@777 3581
ysr@777 3582 int refs_to_scan() { return refs()->size(); }
ysr@777 3583 int overflowed_refs_to_scan() { return overflowed_refs()->length(); }
ysr@777 3584
ysr@777 3585 HeapWord* allocate_slow(GCAllocPurpose purpose, size_t word_sz) {
ysr@777 3586
ysr@777 3587 HeapWord* obj = NULL;
ysr@777 3588 if (word_sz * 100 <
ysr@777 3589 (size_t)(ParallelGCG1AllocBufferSize / HeapWordSize) *
ysr@777 3590 ParallelGCBufferWastePct) {
ysr@777 3591 G1ParGCAllocBuffer* alloc_buf = alloc_buffer(purpose);
ysr@777 3592 add_to_alloc_buffer_waste(alloc_buf->words_remaining());
ysr@777 3593 alloc_buf->retire(false, false);
ysr@777 3594
ysr@777 3595 HeapWord* buf =
ysr@777 3596 _g1h->par_allocate_during_gc(purpose, ParallelGCG1AllocBufferSize / HeapWordSize);
ysr@777 3597 if (buf == NULL) return NULL; // Let caller handle allocation failure.
ysr@777 3598 // Otherwise.
ysr@777 3599 alloc_buf->set_buf(buf);
ysr@777 3600
ysr@777 3601 obj = alloc_buf->allocate(word_sz);
ysr@777 3602 assert(obj != NULL, "buffer was definitely big enough...");
ysr@777 3603 }
ysr@777 3604 else {
ysr@777 3605 obj = _g1h->par_allocate_during_gc(purpose, word_sz);
ysr@777 3606 }
ysr@777 3607 return obj;
ysr@777 3608 }
ysr@777 3609
ysr@777 3610 HeapWord* allocate(GCAllocPurpose purpose, size_t word_sz) {
ysr@777 3611 HeapWord* obj = alloc_buffer(purpose)->allocate(word_sz);
ysr@777 3612 if (obj != NULL) return obj;
ysr@777 3613 return allocate_slow(purpose, word_sz);
ysr@777 3614 }
ysr@777 3615
ysr@777 3616 void undo_allocation(GCAllocPurpose purpose, HeapWord* obj, size_t word_sz) {
ysr@777 3617 if (alloc_buffer(purpose)->contains(obj)) {
ysr@777 3618 guarantee(alloc_buffer(purpose)->contains(obj + word_sz - 1),
ysr@777 3619 "should contain whole object");
ysr@777 3620 alloc_buffer(purpose)->undo_allocation(obj, word_sz);
ysr@777 3621 }
ysr@777 3622 else {
ysr@777 3623 SharedHeap::fill_region_with_object(MemRegion(obj, word_sz));
ysr@777 3624 add_to_undo_waste(word_sz);
ysr@777 3625 }
ysr@777 3626 }
ysr@777 3627
ysr@777 3628 void set_evac_failure_closure(OopsInHeapRegionClosure* evac_failure_cl) {
ysr@777 3629 _evac_failure_cl = evac_failure_cl;
ysr@777 3630 }
ysr@777 3631 OopsInHeapRegionClosure* evac_failure_closure() {
ysr@777 3632 return _evac_failure_cl;
ysr@777 3633 }
ysr@777 3634
ysr@777 3635 void set_evac_closure(G1ParScanHeapEvacClosure* evac_cl) {
ysr@777 3636 _evac_cl = evac_cl;
ysr@777 3637 }
ysr@777 3638
ysr@777 3639 void set_partial_scan_closure(G1ParScanPartialArrayClosure* partial_scan_cl) {
ysr@777 3640 _partial_scan_cl = partial_scan_cl;
ysr@777 3641 }
ysr@777 3642
ysr@777 3643 int* hash_seed() { return &_hash_seed; }
ysr@777 3644 int queue_num() { return _queue_num; }
ysr@777 3645
ysr@777 3646 int term_attempts() { return _term_attempts; }
ysr@777 3647 void note_term_attempt() { _term_attempts++; }
ysr@777 3648
ysr@777 3649 #if G1_DETAILED_STATS
ysr@777 3650 int pushes() { return _pushes; }
ysr@777 3651 int pops() { return _pops; }
ysr@777 3652 int steals() { return _steals; }
ysr@777 3653 int steal_attempts() { return _steal_attempts; }
ysr@777 3654 int overflow_pushes() { return _overflow_pushes; }
ysr@777 3655
ysr@777 3656 void note_push() { _pushes++; }
ysr@777 3657 void note_pop() { _pops++; }
ysr@777 3658 void note_steal() { _steals++; }
ysr@777 3659 void note_steal_attempt() { _steal_attempts++; }
ysr@777 3660 void note_overflow_push() { _overflow_pushes++; }
ysr@777 3661 #endif
ysr@777 3662
ysr@777 3663 void start_strong_roots() {
ysr@777 3664 _start_strong_roots = os::elapsedTime();
ysr@777 3665 }
ysr@777 3666 void end_strong_roots() {
ysr@777 3667 _strong_roots_time += (os::elapsedTime() - _start_strong_roots);
ysr@777 3668 }
ysr@777 3669 double strong_roots_time() { return _strong_roots_time; }
ysr@777 3670
ysr@777 3671 void start_term_time() {
ysr@777 3672 note_term_attempt();
ysr@777 3673 _start_term = os::elapsedTime();
ysr@777 3674 }
ysr@777 3675 void end_term_time() {
ysr@777 3676 _term_time += (os::elapsedTime() - _start_term);
ysr@777 3677 }
ysr@777 3678 double term_time() { return _term_time; }
ysr@777 3679
ysr@777 3680 double elapsed() {
ysr@777 3681 return os::elapsedTime() - _start;
ysr@777 3682 }
ysr@777 3683
ysr@777 3684 size_t* surviving_young_words() {
ysr@777 3685 // We add on to hide entry 0 which accumulates surviving words for
ysr@777 3686 // age -1 regions (i.e. non-young ones)
ysr@777 3687 return _surviving_young_words;
ysr@777 3688 }
ysr@777 3689
ysr@777 3690 void retire_alloc_buffers() {
ysr@777 3691 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) {
ysr@777 3692 size_t waste = _alloc_buffers[ap].words_remaining();
ysr@777 3693 add_to_alloc_buffer_waste(waste);
ysr@777 3694 _alloc_buffers[ap].retire(true, false);
ysr@777 3695 }
ysr@777 3696 }
ysr@777 3697
ysr@777 3698 void trim_queue() {
ysr@777 3699 while (refs_to_scan() > 0 || overflowed_refs_to_scan() > 0) {
ysr@777 3700 oop *ref_to_scan = NULL;
ysr@777 3701 if (overflowed_refs_to_scan() == 0) {
ysr@777 3702 pop_from_queue(ref_to_scan);
ysr@777 3703 } else {
ysr@777 3704 pop_from_overflow_queue(ref_to_scan);
ysr@777 3705 }
ysr@777 3706 if (ref_to_scan != NULL) {
ysr@777 3707 if ((intptr_t)ref_to_scan & G1_PARTIAL_ARRAY_MASK) {
ysr@777 3708 _partial_scan_cl->do_oop_nv(ref_to_scan);
ysr@777 3709 } else {
ysr@777 3710 // Note: we can use "raw" versions of "region_containing" because
ysr@777 3711 // "obj_to_scan" is definitely in the heap, and is not in a
ysr@777 3712 // humongous region.
ysr@777 3713 HeapRegion* r = _g1h->heap_region_containing_raw(ref_to_scan);
ysr@777 3714 _evac_cl->set_region(r);
ysr@777 3715 _evac_cl->do_oop_nv(ref_to_scan);
ysr@777 3716 }
ysr@777 3717 }
ysr@777 3718 }
ysr@777 3719 }
ysr@777 3720 };
ysr@777 3721
ysr@777 3722
ysr@777 3723 G1ParClosureSuper::G1ParClosureSuper(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state) :
ysr@777 3724 _g1(g1), _g1_rem(_g1->g1_rem_set()), _cm(_g1->concurrent_mark()),
ysr@777 3725 _par_scan_state(par_scan_state) { }
ysr@777 3726
ysr@777 3727 // This closure is applied to the fields of the objects that have just been copied.
ysr@777 3728 // Should probably be made inline and moved in g1OopClosures.inline.hpp.
ysr@777 3729 void G1ParScanClosure::do_oop_nv(oop* p) {
ysr@777 3730 oop obj = *p;
ysr@777 3731 if (obj != NULL) {
ysr@777 3732 if (_g1->obj_in_cs(obj)) {
ysr@777 3733 if (obj->is_forwarded()) {
ysr@777 3734 *p = obj->forwardee();
ysr@777 3735 } else {
ysr@777 3736 _par_scan_state->push_on_queue(p);
ysr@777 3737 return;
ysr@777 3738 }
ysr@777 3739 }
ysr@777 3740 _g1_rem->par_write_ref(_from, p, _par_scan_state->queue_num());
ysr@777 3741 }
ysr@777 3742 }
ysr@777 3743
ysr@777 3744 void G1ParCopyHelper::mark_forwardee(oop* p) {
ysr@777 3745 // This is called _after_ do_oop_work has been called, hence after
ysr@777 3746 // the object has been relocated to its new location and *p points
ysr@777 3747 // to its new location.
ysr@777 3748
ysr@777 3749 oop thisOop = *p;
ysr@777 3750 if (thisOop != NULL) {
ysr@777 3751 assert((_g1->evacuation_failed()) || (!_g1->obj_in_cs(thisOop)),
ysr@777 3752 "shouldn't still be in the CSet if evacuation didn't fail.");
ysr@777 3753 HeapWord* addr = (HeapWord*)thisOop;
ysr@777 3754 if (_g1->is_in_g1_reserved(addr))
ysr@777 3755 _cm->grayRoot(oop(addr));
ysr@777 3756 }
ysr@777 3757 }
ysr@777 3758
ysr@777 3759 oop G1ParCopyHelper::copy_to_survivor_space(oop old) {
ysr@777 3760 size_t word_sz = old->size();
ysr@777 3761 HeapRegion* from_region = _g1->heap_region_containing_raw(old);
ysr@777 3762 // +1 to make the -1 indexes valid...
ysr@777 3763 int young_index = from_region->young_index_in_cset()+1;
ysr@777 3764 assert( (from_region->is_young() && young_index > 0) ||
ysr@777 3765 (!from_region->is_young() && young_index == 0), "invariant" );
ysr@777 3766 G1CollectorPolicy* g1p = _g1->g1_policy();
ysr@777 3767 markOop m = old->mark();
ysr@777 3768 GCAllocPurpose alloc_purpose = g1p->evacuation_destination(from_region, m->age(),
ysr@777 3769 word_sz);
ysr@777 3770 HeapWord* obj_ptr = _par_scan_state->allocate(alloc_purpose, word_sz);
ysr@777 3771 oop obj = oop(obj_ptr);
ysr@777 3772
ysr@777 3773 if (obj_ptr == NULL) {
ysr@777 3774 // This will either forward-to-self, or detect that someone else has
ysr@777 3775 // installed a forwarding pointer.
ysr@777 3776 OopsInHeapRegionClosure* cl = _par_scan_state->evac_failure_closure();
ysr@777 3777 return _g1->handle_evacuation_failure_par(cl, old);
ysr@777 3778 }
ysr@777 3779
ysr@777 3780 oop forward_ptr = old->forward_to_atomic(obj);
ysr@777 3781 if (forward_ptr == NULL) {
ysr@777 3782 Copy::aligned_disjoint_words((HeapWord*) old, obj_ptr, word_sz);
ysr@777 3783 obj->set_mark(m);
ysr@777 3784 if (g1p->track_object_age(alloc_purpose)) {
ysr@777 3785 obj->incr_age();
ysr@777 3786 }
ysr@777 3787 // preserve "next" mark bit
ysr@777 3788 if (_g1->mark_in_progress() && !_g1->is_obj_ill(old)) {
ysr@777 3789 if (!use_local_bitmaps ||
ysr@777 3790 !_par_scan_state->alloc_buffer(alloc_purpose)->mark(obj_ptr)) {
ysr@777 3791 // if we couldn't mark it on the local bitmap (this happens when
ysr@777 3792 // the object was not allocated in the GCLab), we have to bite
ysr@777 3793 // the bullet and do the standard parallel mark
ysr@777 3794 _cm->markAndGrayObjectIfNecessary(obj);
ysr@777 3795 }
ysr@777 3796 #if 1
ysr@777 3797 if (_g1->isMarkedNext(old)) {
ysr@777 3798 _cm->nextMarkBitMap()->parClear((HeapWord*)old);
ysr@777 3799 }
ysr@777 3800 #endif
ysr@777 3801 }
ysr@777 3802
ysr@777 3803 size_t* surv_young_words = _par_scan_state->surviving_young_words();
ysr@777 3804 surv_young_words[young_index] += word_sz;
ysr@777 3805
ysr@777 3806 if (obj->is_objArray() && arrayOop(obj)->length() >= ParGCArrayScanChunk) {
ysr@777 3807 arrayOop(old)->set_length(0);
ysr@777 3808 _par_scan_state->push_on_queue((oop*) ((intptr_t)old | G1_PARTIAL_ARRAY_MASK));
ysr@777 3809 } else {
ysr@777 3810 _scanner->set_region(_g1->heap_region_containing(obj));
ysr@777 3811 obj->oop_iterate_backwards(_scanner);
ysr@777 3812 }
ysr@777 3813 } else {
ysr@777 3814 _par_scan_state->undo_allocation(alloc_purpose, obj_ptr, word_sz);
ysr@777 3815 obj = forward_ptr;
ysr@777 3816 }
ysr@777 3817 return obj;
ysr@777 3818 }
ysr@777 3819
ysr@777 3820 template<bool do_gen_barrier, G1Barrier barrier, bool do_mark_forwardee>
ysr@777 3821 void G1ParCopyClosure<do_gen_barrier, barrier, do_mark_forwardee>::do_oop_work(oop* p) {
ysr@777 3822 oop obj = *p;
ysr@777 3823 assert(barrier != G1BarrierRS || obj != NULL,
ysr@777 3824 "Precondition: G1BarrierRS implies obj is nonNull");
ysr@777 3825
ysr@777 3826 if (obj != NULL) {
ysr@777 3827 if (_g1->obj_in_cs(obj)) {
ysr@777 3828 #if G1_REM_SET_LOGGING
ysr@777 3829 gclog_or_tty->print_cr("Loc "PTR_FORMAT" contains pointer "PTR_FORMAT" into CS.",
ysr@777 3830 p, (void*) obj);
ysr@777 3831 #endif
ysr@777 3832 if (obj->is_forwarded()) {
ysr@777 3833 *p = obj->forwardee();
ysr@777 3834 } else {
ysr@777 3835 *p = copy_to_survivor_space(obj);
ysr@777 3836 }
ysr@777 3837 // When scanning the RS, we only care about objs in CS.
ysr@777 3838 if (barrier == G1BarrierRS) {
ysr@777 3839 _g1_rem->par_write_ref(_from, p, _par_scan_state->queue_num());
ysr@777 3840 }
ysr@777 3841 }
ysr@777 3842 // When scanning moved objs, must look at all oops.
ysr@777 3843 if (barrier == G1BarrierEvac) {
ysr@777 3844 _g1_rem->par_write_ref(_from, p, _par_scan_state->queue_num());
ysr@777 3845 }
ysr@777 3846
ysr@777 3847 if (do_gen_barrier) {
ysr@777 3848 par_do_barrier(p);
ysr@777 3849 }
ysr@777 3850 }
ysr@777 3851 }
ysr@777 3852
ysr@777 3853 template void G1ParCopyClosure<false, G1BarrierEvac, false>::do_oop_work(oop* p);
ysr@777 3854
ysr@777 3855 template <class T> void G1ParScanPartialArrayClosure::process_array_chunk(
ysr@777 3856 oop obj, int start, int end) {
ysr@777 3857 // process our set of indices (include header in first chunk)
ysr@777 3858 assert(start < end, "invariant");
ysr@777 3859 T* const base = (T*)objArrayOop(obj)->base();
ysr@777 3860 T* const start_addr = base + start;
ysr@777 3861 T* const end_addr = base + end;
ysr@777 3862 MemRegion mr((HeapWord*)start_addr, (HeapWord*)end_addr);
ysr@777 3863 _scanner.set_region(_g1->heap_region_containing(obj));
ysr@777 3864 obj->oop_iterate(&_scanner, mr);
ysr@777 3865 }
ysr@777 3866
ysr@777 3867 void G1ParScanPartialArrayClosure::do_oop_nv(oop* p) {
ysr@777 3868 assert(!UseCompressedOops, "Needs to be fixed to work with compressed oops");
ysr@777 3869 oop old = oop((intptr_t)p & ~G1_PARTIAL_ARRAY_MASK);
ysr@777 3870 assert(old->is_objArray(), "must be obj array");
ysr@777 3871 assert(old->is_forwarded(), "must be forwarded");
ysr@777 3872 assert(Universe::heap()->is_in_reserved(old), "must be in heap.");
ysr@777 3873
ysr@777 3874 objArrayOop obj = objArrayOop(old->forwardee());
ysr@777 3875 assert((void*)old != (void*)old->forwardee(), "self forwarding here?");
ysr@777 3876 // Process ParGCArrayScanChunk elements now
ysr@777 3877 // and push the remainder back onto queue
ysr@777 3878 int start = arrayOop(old)->length();
ysr@777 3879 int end = obj->length();
ysr@777 3880 int remainder = end - start;
ysr@777 3881 assert(start <= end, "just checking");
ysr@777 3882 if (remainder > 2 * ParGCArrayScanChunk) {
ysr@777 3883 // Test above combines last partial chunk with a full chunk
ysr@777 3884 end = start + ParGCArrayScanChunk;
ysr@777 3885 arrayOop(old)->set_length(end);
ysr@777 3886 // Push remainder.
ysr@777 3887 _par_scan_state->push_on_queue((oop*) ((intptr_t) old | G1_PARTIAL_ARRAY_MASK));
ysr@777 3888 } else {
ysr@777 3889 // Restore length so that the heap remains parsable in
ysr@777 3890 // case of evacuation failure.
ysr@777 3891 arrayOop(old)->set_length(end);
ysr@777 3892 }
ysr@777 3893
ysr@777 3894 // process our set of indices (include header in first chunk)
ysr@777 3895 process_array_chunk<oop>(obj, start, end);
ysr@777 3896 oop* start_addr = start == 0 ? (oop*)obj : obj->obj_at_addr<oop>(start);
ysr@777 3897 oop* end_addr = (oop*)(obj->base()) + end; // obj_at_addr(end) asserts end < length
ysr@777 3898 MemRegion mr((HeapWord*)start_addr, (HeapWord*)end_addr);
ysr@777 3899 _scanner.set_region(_g1->heap_region_containing(obj));
ysr@777 3900 obj->oop_iterate(&_scanner, mr);
ysr@777 3901 }
ysr@777 3902
ysr@777 3903 int G1ScanAndBalanceClosure::_nq = 0;
ysr@777 3904
ysr@777 3905 class G1ParEvacuateFollowersClosure : public VoidClosure {
ysr@777 3906 protected:
ysr@777 3907 G1CollectedHeap* _g1h;
ysr@777 3908 G1ParScanThreadState* _par_scan_state;
ysr@777 3909 RefToScanQueueSet* _queues;
ysr@777 3910 ParallelTaskTerminator* _terminator;
ysr@777 3911
ysr@777 3912 G1ParScanThreadState* par_scan_state() { return _par_scan_state; }
ysr@777 3913 RefToScanQueueSet* queues() { return _queues; }
ysr@777 3914 ParallelTaskTerminator* terminator() { return _terminator; }
ysr@777 3915
ysr@777 3916 public:
ysr@777 3917 G1ParEvacuateFollowersClosure(G1CollectedHeap* g1h,
ysr@777 3918 G1ParScanThreadState* par_scan_state,
ysr@777 3919 RefToScanQueueSet* queues,
ysr@777 3920 ParallelTaskTerminator* terminator)
ysr@777 3921 : _g1h(g1h), _par_scan_state(par_scan_state),
ysr@777 3922 _queues(queues), _terminator(terminator) {}
ysr@777 3923
ysr@777 3924 void do_void() {
ysr@777 3925 G1ParScanThreadState* pss = par_scan_state();
ysr@777 3926 while (true) {
ysr@777 3927 oop* ref_to_scan;
ysr@777 3928 pss->trim_queue();
ysr@777 3929 IF_G1_DETAILED_STATS(pss->note_steal_attempt());
ysr@777 3930 if (queues()->steal(pss->queue_num(),
ysr@777 3931 pss->hash_seed(),
ysr@777 3932 ref_to_scan)) {
ysr@777 3933 IF_G1_DETAILED_STATS(pss->note_steal());
ysr@777 3934 pss->push_on_queue(ref_to_scan);
ysr@777 3935 continue;
ysr@777 3936 }
ysr@777 3937 pss->start_term_time();
ysr@777 3938 if (terminator()->offer_termination()) break;
ysr@777 3939 pss->end_term_time();
ysr@777 3940 }
ysr@777 3941 pss->end_term_time();
ysr@777 3942 pss->retire_alloc_buffers();
ysr@777 3943 }
ysr@777 3944 };
ysr@777 3945
ysr@777 3946 class G1ParTask : public AbstractGangTask {
ysr@777 3947 protected:
ysr@777 3948 G1CollectedHeap* _g1h;
ysr@777 3949 RefToScanQueueSet *_queues;
ysr@777 3950 ParallelTaskTerminator _terminator;
ysr@777 3951
ysr@777 3952 Mutex _stats_lock;
ysr@777 3953 Mutex* stats_lock() { return &_stats_lock; }
ysr@777 3954
ysr@777 3955 size_t getNCards() {
ysr@777 3956 return (_g1h->capacity() + G1BlockOffsetSharedArray::N_bytes - 1)
ysr@777 3957 / G1BlockOffsetSharedArray::N_bytes;
ysr@777 3958 }
ysr@777 3959
ysr@777 3960 public:
ysr@777 3961 G1ParTask(G1CollectedHeap* g1h, int workers, RefToScanQueueSet *task_queues)
ysr@777 3962 : AbstractGangTask("G1 collection"),
ysr@777 3963 _g1h(g1h),
ysr@777 3964 _queues(task_queues),
ysr@777 3965 _terminator(workers, _queues),
ysr@777 3966 _stats_lock(Mutex::leaf, "parallel G1 stats lock", true)
ysr@777 3967 {}
ysr@777 3968
ysr@777 3969 RefToScanQueueSet* queues() { return _queues; }
ysr@777 3970
ysr@777 3971 RefToScanQueue *work_queue(int i) {
ysr@777 3972 return queues()->queue(i);
ysr@777 3973 }
ysr@777 3974
ysr@777 3975 void work(int i) {
ysr@777 3976 ResourceMark rm;
ysr@777 3977 HandleMark hm;
ysr@777 3978
ysr@777 3979 G1ParScanThreadState pss(_g1h, i);
ysr@777 3980 G1ParScanHeapEvacClosure scan_evac_cl(_g1h, &pss);
ysr@777 3981 G1ParScanHeapEvacClosure evac_failure_cl(_g1h, &pss);
ysr@777 3982 G1ParScanPartialArrayClosure partial_scan_cl(_g1h, &pss);
ysr@777 3983
ysr@777 3984 pss.set_evac_closure(&scan_evac_cl);
ysr@777 3985 pss.set_evac_failure_closure(&evac_failure_cl);
ysr@777 3986 pss.set_partial_scan_closure(&partial_scan_cl);
ysr@777 3987
ysr@777 3988 G1ParScanExtRootClosure only_scan_root_cl(_g1h, &pss);
ysr@777 3989 G1ParScanPermClosure only_scan_perm_cl(_g1h, &pss);
ysr@777 3990 G1ParScanHeapRSClosure only_scan_heap_rs_cl(_g1h, &pss);
ysr@777 3991 G1ParScanAndMarkExtRootClosure scan_mark_root_cl(_g1h, &pss);
ysr@777 3992 G1ParScanAndMarkPermClosure scan_mark_perm_cl(_g1h, &pss);
ysr@777 3993 G1ParScanAndMarkHeapRSClosure scan_mark_heap_rs_cl(_g1h, &pss);
ysr@777 3994
ysr@777 3995 OopsInHeapRegionClosure *scan_root_cl;
ysr@777 3996 OopsInHeapRegionClosure *scan_perm_cl;
ysr@777 3997 OopsInHeapRegionClosure *scan_so_cl;
ysr@777 3998
ysr@777 3999 if (_g1h->g1_policy()->should_initiate_conc_mark()) {
ysr@777 4000 scan_root_cl = &scan_mark_root_cl;
ysr@777 4001 scan_perm_cl = &scan_mark_perm_cl;
ysr@777 4002 scan_so_cl = &scan_mark_heap_rs_cl;
ysr@777 4003 } else {
ysr@777 4004 scan_root_cl = &only_scan_root_cl;
ysr@777 4005 scan_perm_cl = &only_scan_perm_cl;
ysr@777 4006 scan_so_cl = &only_scan_heap_rs_cl;
ysr@777 4007 }
ysr@777 4008
ysr@777 4009 pss.start_strong_roots();
ysr@777 4010 _g1h->g1_process_strong_roots(/* not collecting perm */ false,
ysr@777 4011 SharedHeap::SO_AllClasses,
ysr@777 4012 scan_root_cl,
ysr@777 4013 &only_scan_heap_rs_cl,
ysr@777 4014 scan_so_cl,
ysr@777 4015 scan_perm_cl,
ysr@777 4016 i);
ysr@777 4017 pss.end_strong_roots();
ysr@777 4018 {
ysr@777 4019 double start = os::elapsedTime();
ysr@777 4020 G1ParEvacuateFollowersClosure evac(_g1h, &pss, _queues, &_terminator);
ysr@777 4021 evac.do_void();
ysr@777 4022 double elapsed_ms = (os::elapsedTime()-start)*1000.0;
ysr@777 4023 double term_ms = pss.term_time()*1000.0;
ysr@777 4024 _g1h->g1_policy()->record_obj_copy_time(i, elapsed_ms-term_ms);
ysr@777 4025 _g1h->g1_policy()->record_termination_time(i, term_ms);
ysr@777 4026 }
ysr@777 4027 _g1h->update_surviving_young_words(pss.surviving_young_words()+1);
ysr@777 4028
ysr@777 4029 // Clean up any par-expanded rem sets.
ysr@777 4030 HeapRegionRemSet::par_cleanup();
ysr@777 4031
ysr@777 4032 MutexLocker x(stats_lock());
ysr@777 4033 if (ParallelGCVerbose) {
ysr@777 4034 gclog_or_tty->print("Thread %d complete:\n", i);
ysr@777 4035 #if G1_DETAILED_STATS
ysr@777 4036 gclog_or_tty->print(" Pushes: %7d Pops: %7d Overflows: %7d Steals %7d (in %d attempts)\n",
ysr@777 4037 pss.pushes(),
ysr@777 4038 pss.pops(),
ysr@777 4039 pss.overflow_pushes(),
ysr@777 4040 pss.steals(),
ysr@777 4041 pss.steal_attempts());
ysr@777 4042 #endif
ysr@777 4043 double elapsed = pss.elapsed();
ysr@777 4044 double strong_roots = pss.strong_roots_time();
ysr@777 4045 double term = pss.term_time();
ysr@777 4046 gclog_or_tty->print(" Elapsed: %7.2f ms.\n"
ysr@777 4047 " Strong roots: %7.2f ms (%6.2f%%)\n"
ysr@777 4048 " Termination: %7.2f ms (%6.2f%%) (in %d entries)\n",
ysr@777 4049 elapsed * 1000.0,
ysr@777 4050 strong_roots * 1000.0, (strong_roots*100.0/elapsed),
ysr@777 4051 term * 1000.0, (term*100.0/elapsed),
ysr@777 4052 pss.term_attempts());
ysr@777 4053 size_t total_waste = pss.alloc_buffer_waste() + pss.undo_waste();
ysr@777 4054 gclog_or_tty->print(" Waste: %8dK\n"
ysr@777 4055 " Alloc Buffer: %8dK\n"
ysr@777 4056 " Undo: %8dK\n",
ysr@777 4057 (total_waste * HeapWordSize) / K,
ysr@777 4058 (pss.alloc_buffer_waste() * HeapWordSize) / K,
ysr@777 4059 (pss.undo_waste() * HeapWordSize) / K);
ysr@777 4060 }
ysr@777 4061
ysr@777 4062 assert(pss.refs_to_scan() == 0, "Task queue should be empty");
ysr@777 4063 assert(pss.overflowed_refs_to_scan() == 0, "Overflow queue should be empty");
ysr@777 4064 }
ysr@777 4065 };
ysr@777 4066
ysr@777 4067 // *** Common G1 Evacuation Stuff
ysr@777 4068
ysr@777 4069 class G1CountClosure: public OopsInHeapRegionClosure {
ysr@777 4070 public:
ysr@777 4071 int n;
ysr@777 4072 G1CountClosure() : n(0) {}
ysr@777 4073 void do_oop(narrowOop* p) {
ysr@777 4074 guarantee(false, "NYI");
ysr@777 4075 }
ysr@777 4076 void do_oop(oop* p) {
ysr@777 4077 oop obj = *p;
ysr@777 4078 assert(obj != NULL && G1CollectedHeap::heap()->obj_in_cs(obj),
ysr@777 4079 "Rem set closure called on non-rem-set pointer.");
ysr@777 4080 n++;
ysr@777 4081 }
ysr@777 4082 };
ysr@777 4083
ysr@777 4084 static G1CountClosure count_closure;
ysr@777 4085
ysr@777 4086 void
ysr@777 4087 G1CollectedHeap::
ysr@777 4088 g1_process_strong_roots(bool collecting_perm_gen,
ysr@777 4089 SharedHeap::ScanningOption so,
ysr@777 4090 OopClosure* scan_non_heap_roots,
ysr@777 4091 OopsInHeapRegionClosure* scan_rs,
ysr@777 4092 OopsInHeapRegionClosure* scan_so,
ysr@777 4093 OopsInGenClosure* scan_perm,
ysr@777 4094 int worker_i) {
ysr@777 4095 // First scan the strong roots, including the perm gen.
ysr@777 4096 double ext_roots_start = os::elapsedTime();
ysr@777 4097 double closure_app_time_sec = 0.0;
ysr@777 4098
ysr@777 4099 BufferingOopClosure buf_scan_non_heap_roots(scan_non_heap_roots);
ysr@777 4100 BufferingOopsInGenClosure buf_scan_perm(scan_perm);
ysr@777 4101 buf_scan_perm.set_generation(perm_gen());
ysr@777 4102
ysr@777 4103 process_strong_roots(collecting_perm_gen, so,
ysr@777 4104 &buf_scan_non_heap_roots,
ysr@777 4105 &buf_scan_perm);
ysr@777 4106 // Finish up any enqueued closure apps.
ysr@777 4107 buf_scan_non_heap_roots.done();
ysr@777 4108 buf_scan_perm.done();
ysr@777 4109 double ext_roots_end = os::elapsedTime();
ysr@777 4110 g1_policy()->reset_obj_copy_time(worker_i);
ysr@777 4111 double obj_copy_time_sec =
ysr@777 4112 buf_scan_non_heap_roots.closure_app_seconds() +
ysr@777 4113 buf_scan_perm.closure_app_seconds();
ysr@777 4114 g1_policy()->record_obj_copy_time(worker_i, obj_copy_time_sec * 1000.0);
ysr@777 4115 double ext_root_time_ms =
ysr@777 4116 ((ext_roots_end - ext_roots_start) - obj_copy_time_sec) * 1000.0;
ysr@777 4117 g1_policy()->record_ext_root_scan_time(worker_i, ext_root_time_ms);
ysr@777 4118
ysr@777 4119 // Scan strong roots in mark stack.
ysr@777 4120 if (!_process_strong_tasks->is_task_claimed(G1H_PS_mark_stack_oops_do)) {
ysr@777 4121 concurrent_mark()->oops_do(scan_non_heap_roots);
ysr@777 4122 }
ysr@777 4123 double mark_stack_scan_ms = (os::elapsedTime() - ext_roots_end) * 1000.0;
ysr@777 4124 g1_policy()->record_mark_stack_scan_time(worker_i, mark_stack_scan_ms);
ysr@777 4125
ysr@777 4126 // XXX What should this be doing in the parallel case?
ysr@777 4127 g1_policy()->record_collection_pause_end_CH_strong_roots();
ysr@777 4128 if (G1VerifyRemSet) {
ysr@777 4129 // :::: FIXME ::::
ysr@777 4130 // The stupid remembered set doesn't know how to filter out dead
ysr@777 4131 // objects, which the smart one does, and so when it is created
ysr@777 4132 // and then compared the number of entries in each differs and
ysr@777 4133 // the verification code fails.
ysr@777 4134 guarantee(false, "verification code is broken, see note");
ysr@777 4135
ysr@777 4136 // Let's make sure that the current rem set agrees with the stupidest
ysr@777 4137 // one possible!
ysr@777 4138 bool refs_enabled = ref_processor()->discovery_enabled();
ysr@777 4139 if (refs_enabled) ref_processor()->disable_discovery();
ysr@777 4140 StupidG1RemSet stupid(this);
ysr@777 4141 count_closure.n = 0;
ysr@777 4142 stupid.oops_into_collection_set_do(&count_closure, worker_i);
ysr@777 4143 int stupid_n = count_closure.n;
ysr@777 4144 count_closure.n = 0;
ysr@777 4145 g1_rem_set()->oops_into_collection_set_do(&count_closure, worker_i);
ysr@777 4146 guarantee(count_closure.n == stupid_n, "Old and new rem sets differ.");
ysr@777 4147 gclog_or_tty->print_cr("\nFound %d pointers in heap RS.", count_closure.n);
ysr@777 4148 if (refs_enabled) ref_processor()->enable_discovery();
ysr@777 4149 }
ysr@777 4150 if (scan_so != NULL) {
ysr@777 4151 scan_scan_only_set(scan_so, worker_i);
ysr@777 4152 }
ysr@777 4153 // Now scan the complement of the collection set.
ysr@777 4154 if (scan_rs != NULL) {
ysr@777 4155 g1_rem_set()->oops_into_collection_set_do(scan_rs, worker_i);
ysr@777 4156 }
ysr@777 4157 // Finish with the ref_processor roots.
ysr@777 4158 if (!_process_strong_tasks->is_task_claimed(G1H_PS_refProcessor_oops_do)) {
ysr@777 4159 ref_processor()->oops_do(scan_non_heap_roots);
ysr@777 4160 }
ysr@777 4161 g1_policy()->record_collection_pause_end_G1_strong_roots();
ysr@777 4162 _process_strong_tasks->all_tasks_completed();
ysr@777 4163 }
ysr@777 4164
ysr@777 4165 void
ysr@777 4166 G1CollectedHeap::scan_scan_only_region(HeapRegion* r,
ysr@777 4167 OopsInHeapRegionClosure* oc,
ysr@777 4168 int worker_i) {
ysr@777 4169 HeapWord* startAddr = r->bottom();
ysr@777 4170 HeapWord* endAddr = r->used_region().end();
ysr@777 4171
ysr@777 4172 oc->set_region(r);
ysr@777 4173
ysr@777 4174 HeapWord* p = r->bottom();
ysr@777 4175 HeapWord* t = r->top();
ysr@777 4176 guarantee( p == r->next_top_at_mark_start(), "invariant" );
ysr@777 4177 while (p < t) {
ysr@777 4178 oop obj = oop(p);
ysr@777 4179 p += obj->oop_iterate(oc);
ysr@777 4180 }
ysr@777 4181 }
ysr@777 4182
ysr@777 4183 void
ysr@777 4184 G1CollectedHeap::scan_scan_only_set(OopsInHeapRegionClosure* oc,
ysr@777 4185 int worker_i) {
ysr@777 4186 double start = os::elapsedTime();
ysr@777 4187
ysr@777 4188 BufferingOopsInHeapRegionClosure boc(oc);
ysr@777 4189
ysr@777 4190 FilterInHeapRegionAndIntoCSClosure scan_only(this, &boc);
ysr@777 4191 FilterAndMarkInHeapRegionAndIntoCSClosure scan_and_mark(this, &boc, concurrent_mark());
ysr@777 4192
ysr@777 4193 OopsInHeapRegionClosure *foc;
ysr@777 4194 if (g1_policy()->should_initiate_conc_mark())
ysr@777 4195 foc = &scan_and_mark;
ysr@777 4196 else
ysr@777 4197 foc = &scan_only;
ysr@777 4198
ysr@777 4199 HeapRegion* hr;
ysr@777 4200 int n = 0;
ysr@777 4201 while ((hr = _young_list->par_get_next_scan_only_region()) != NULL) {
ysr@777 4202 scan_scan_only_region(hr, foc, worker_i);
ysr@777 4203 ++n;
ysr@777 4204 }
ysr@777 4205 boc.done();
ysr@777 4206
ysr@777 4207 double closure_app_s = boc.closure_app_seconds();
ysr@777 4208 g1_policy()->record_obj_copy_time(worker_i, closure_app_s * 1000.0);
ysr@777 4209 double ms = (os::elapsedTime() - start - closure_app_s)*1000.0;
ysr@777 4210 g1_policy()->record_scan_only_time(worker_i, ms, n);
ysr@777 4211 }
ysr@777 4212
ysr@777 4213 void
ysr@777 4214 G1CollectedHeap::g1_process_weak_roots(OopClosure* root_closure,
ysr@777 4215 OopClosure* non_root_closure) {
ysr@777 4216 SharedHeap::process_weak_roots(root_closure, non_root_closure);
ysr@777 4217 }
ysr@777 4218
ysr@777 4219
ysr@777 4220 class SaveMarksClosure: public HeapRegionClosure {
ysr@777 4221 public:
ysr@777 4222 bool doHeapRegion(HeapRegion* r) {
ysr@777 4223 r->save_marks();
ysr@777 4224 return false;
ysr@777 4225 }
ysr@777 4226 };
ysr@777 4227
ysr@777 4228 void G1CollectedHeap::save_marks() {
ysr@777 4229 if (ParallelGCThreads == 0) {
ysr@777 4230 SaveMarksClosure sm;
ysr@777 4231 heap_region_iterate(&sm);
ysr@777 4232 }
ysr@777 4233 // We do this even in the parallel case
ysr@777 4234 perm_gen()->save_marks();
ysr@777 4235 }
ysr@777 4236
ysr@777 4237 void G1CollectedHeap::evacuate_collection_set() {
ysr@777 4238 set_evacuation_failed(false);
ysr@777 4239
ysr@777 4240 g1_rem_set()->prepare_for_oops_into_collection_set_do();
ysr@777 4241 concurrent_g1_refine()->set_use_cache(false);
ysr@777 4242 int n_workers = (ParallelGCThreads > 0 ? workers()->total_workers() : 1);
ysr@777 4243
ysr@777 4244 set_par_threads(n_workers);
ysr@777 4245 G1ParTask g1_par_task(this, n_workers, _task_queues);
ysr@777 4246
ysr@777 4247 init_for_evac_failure(NULL);
ysr@777 4248
ysr@777 4249 change_strong_roots_parity(); // In preparation for parallel strong roots.
ysr@777 4250 rem_set()->prepare_for_younger_refs_iterate(true);
ysr@777 4251 double start_par = os::elapsedTime();
ysr@777 4252
ysr@777 4253 if (ParallelGCThreads > 0) {
ysr@777 4254 // The individual threads will set their evac-failure closures.
ysr@777 4255 workers()->run_task(&g1_par_task);
ysr@777 4256 } else {
ysr@777 4257 g1_par_task.work(0);
ysr@777 4258 }
ysr@777 4259
ysr@777 4260 double par_time = (os::elapsedTime() - start_par) * 1000.0;
ysr@777 4261 g1_policy()->record_par_time(par_time);
ysr@777 4262 set_par_threads(0);
ysr@777 4263 // Is this the right thing to do here? We don't save marks
ysr@777 4264 // on individual heap regions when we allocate from
ysr@777 4265 // them in parallel, so this seems like the correct place for this.
ysr@777 4266 all_alloc_regions_note_end_of_copying();
ysr@777 4267 {
ysr@777 4268 G1IsAliveClosure is_alive(this);
ysr@777 4269 G1KeepAliveClosure keep_alive(this);
ysr@777 4270 JNIHandles::weak_oops_do(&is_alive, &keep_alive);
ysr@777 4271 }
ysr@777 4272
ysr@777 4273 g1_rem_set()->cleanup_after_oops_into_collection_set_do();
ysr@777 4274 concurrent_g1_refine()->set_use_cache(true);
ysr@777 4275
ysr@777 4276 finalize_for_evac_failure();
ysr@777 4277
ysr@777 4278 // Must do this before removing self-forwarding pointers, which clears
ysr@777 4279 // the per-region evac-failure flags.
ysr@777 4280 concurrent_mark()->complete_marking_in_collection_set();
ysr@777 4281
ysr@777 4282 if (evacuation_failed()) {
ysr@777 4283 remove_self_forwarding_pointers();
ysr@777 4284
ysr@777 4285 if (PrintGCDetails) {
ysr@777 4286 gclog_or_tty->print(" (evacuation failed)");
ysr@777 4287 } else if (PrintGC) {
ysr@777 4288 gclog_or_tty->print("--");
ysr@777 4289 }
ysr@777 4290 }
ysr@777 4291
ysr@777 4292 COMPILER2_PRESENT(DerivedPointerTable::update_pointers());
ysr@777 4293 }
ysr@777 4294
ysr@777 4295 void G1CollectedHeap::free_region(HeapRegion* hr) {
ysr@777 4296 size_t pre_used = 0;
ysr@777 4297 size_t cleared_h_regions = 0;
ysr@777 4298 size_t freed_regions = 0;
ysr@777 4299 UncleanRegionList local_list;
ysr@777 4300
ysr@777 4301 HeapWord* start = hr->bottom();
ysr@777 4302 HeapWord* end = hr->prev_top_at_mark_start();
ysr@777 4303 size_t used_bytes = hr->used();
ysr@777 4304 size_t live_bytes = hr->max_live_bytes();
ysr@777 4305 if (used_bytes > 0) {
ysr@777 4306 guarantee( live_bytes <= used_bytes, "invariant" );
ysr@777 4307 } else {
ysr@777 4308 guarantee( live_bytes == 0, "invariant" );
ysr@777 4309 }
ysr@777 4310
ysr@777 4311 size_t garbage_bytes = used_bytes - live_bytes;
ysr@777 4312 if (garbage_bytes > 0)
ysr@777 4313 g1_policy()->decrease_known_garbage_bytes(garbage_bytes);
ysr@777 4314
ysr@777 4315 free_region_work(hr, pre_used, cleared_h_regions, freed_regions,
ysr@777 4316 &local_list);
ysr@777 4317 finish_free_region_work(pre_used, cleared_h_regions, freed_regions,
ysr@777 4318 &local_list);
ysr@777 4319 }
ysr@777 4320
ysr@777 4321 void
ysr@777 4322 G1CollectedHeap::free_region_work(HeapRegion* hr,
ysr@777 4323 size_t& pre_used,
ysr@777 4324 size_t& cleared_h_regions,
ysr@777 4325 size_t& freed_regions,
ysr@777 4326 UncleanRegionList* list,
ysr@777 4327 bool par) {
ysr@777 4328 assert(!hr->popular(), "should not free popular regions");
ysr@777 4329 pre_used += hr->used();
ysr@777 4330 if (hr->isHumongous()) {
ysr@777 4331 assert(hr->startsHumongous(),
ysr@777 4332 "Only the start of a humongous region should be freed.");
ysr@777 4333 int ind = _hrs->find(hr);
ysr@777 4334 assert(ind != -1, "Should have an index.");
ysr@777 4335 // Clear the start region.
ysr@777 4336 hr->hr_clear(par, true /*clear_space*/);
ysr@777 4337 list->insert_before_head(hr);
ysr@777 4338 cleared_h_regions++;
ysr@777 4339 freed_regions++;
ysr@777 4340 // Clear any continued regions.
ysr@777 4341 ind++;
ysr@777 4342 while ((size_t)ind < n_regions()) {
ysr@777 4343 HeapRegion* hrc = _hrs->at(ind);
ysr@777 4344 if (!hrc->continuesHumongous()) break;
ysr@777 4345 // Otherwise, does continue the H region.
ysr@777 4346 assert(hrc->humongous_start_region() == hr, "Huh?");
ysr@777 4347 hrc->hr_clear(par, true /*clear_space*/);
ysr@777 4348 cleared_h_regions++;
ysr@777 4349 freed_regions++;
ysr@777 4350 list->insert_before_head(hrc);
ysr@777 4351 ind++;
ysr@777 4352 }
ysr@777 4353 } else {
ysr@777 4354 hr->hr_clear(par, true /*clear_space*/);
ysr@777 4355 list->insert_before_head(hr);
ysr@777 4356 freed_regions++;
ysr@777 4357 // If we're using clear2, this should not be enabled.
ysr@777 4358 // assert(!hr->in_cohort(), "Can't be both free and in a cohort.");
ysr@777 4359 }
ysr@777 4360 }
ysr@777 4361
ysr@777 4362 void G1CollectedHeap::finish_free_region_work(size_t pre_used,
ysr@777 4363 size_t cleared_h_regions,
ysr@777 4364 size_t freed_regions,
ysr@777 4365 UncleanRegionList* list) {
ysr@777 4366 if (list != NULL && list->sz() > 0) {
ysr@777 4367 prepend_region_list_on_unclean_list(list);
ysr@777 4368 }
ysr@777 4369 // Acquire a lock, if we're parallel, to update possibly-shared
ysr@777 4370 // variables.
ysr@777 4371 Mutex* lock = (n_par_threads() > 0) ? ParGCRareEvent_lock : NULL;
ysr@777 4372 {
ysr@777 4373 MutexLockerEx x(lock, Mutex::_no_safepoint_check_flag);
ysr@777 4374 _summary_bytes_used -= pre_used;
ysr@777 4375 _num_humongous_regions -= (int) cleared_h_regions;
ysr@777 4376 _free_regions += freed_regions;
ysr@777 4377 }
ysr@777 4378 }
ysr@777 4379
ysr@777 4380
ysr@777 4381 void G1CollectedHeap::dirtyCardsForYoungRegions(CardTableModRefBS* ct_bs, HeapRegion* list) {
ysr@777 4382 while (list != NULL) {
ysr@777 4383 guarantee( list->is_young(), "invariant" );
ysr@777 4384
ysr@777 4385 HeapWord* bottom = list->bottom();
ysr@777 4386 HeapWord* end = list->end();
ysr@777 4387 MemRegion mr(bottom, end);
ysr@777 4388 ct_bs->dirty(mr);
ysr@777 4389
ysr@777 4390 list = list->get_next_young_region();
ysr@777 4391 }
ysr@777 4392 }
ysr@777 4393
ysr@777 4394 void G1CollectedHeap::cleanUpCardTable() {
ysr@777 4395 CardTableModRefBS* ct_bs = (CardTableModRefBS*) (barrier_set());
ysr@777 4396 double start = os::elapsedTime();
ysr@777 4397
ysr@777 4398 ct_bs->clear(_g1_committed);
ysr@777 4399
ysr@777 4400 // now, redirty the cards of the scan-only and survivor regions
ysr@777 4401 // (it seemed faster to do it this way, instead of iterating over
ysr@777 4402 // all regions and then clearing / dirtying as approprite)
ysr@777 4403 dirtyCardsForYoungRegions(ct_bs, _young_list->first_scan_only_region());
ysr@777 4404 dirtyCardsForYoungRegions(ct_bs, _young_list->first_survivor_region());
ysr@777 4405
ysr@777 4406 double elapsed = os::elapsedTime() - start;
ysr@777 4407 g1_policy()->record_clear_ct_time( elapsed * 1000.0);
ysr@777 4408 }
ysr@777 4409
ysr@777 4410
ysr@777 4411 void G1CollectedHeap::do_collection_pause_if_appropriate(size_t word_size) {
ysr@777 4412 // First do any popular regions.
ysr@777 4413 HeapRegion* hr;
ysr@777 4414 while ((hr = popular_region_to_evac()) != NULL) {
ysr@777 4415 evac_popular_region(hr);
ysr@777 4416 }
ysr@777 4417 // Now do heuristic pauses.
ysr@777 4418 if (g1_policy()->should_do_collection_pause(word_size)) {
ysr@777 4419 do_collection_pause();
ysr@777 4420 }
ysr@777 4421 }
ysr@777 4422
ysr@777 4423 void G1CollectedHeap::free_collection_set(HeapRegion* cs_head) {
ysr@777 4424 double young_time_ms = 0.0;
ysr@777 4425 double non_young_time_ms = 0.0;
ysr@777 4426
ysr@777 4427 G1CollectorPolicy* policy = g1_policy();
ysr@777 4428
ysr@777 4429 double start_sec = os::elapsedTime();
ysr@777 4430 bool non_young = true;
ysr@777 4431
ysr@777 4432 HeapRegion* cur = cs_head;
ysr@777 4433 int age_bound = -1;
ysr@777 4434 size_t rs_lengths = 0;
ysr@777 4435
ysr@777 4436 while (cur != NULL) {
ysr@777 4437 if (non_young) {
ysr@777 4438 if (cur->is_young()) {
ysr@777 4439 double end_sec = os::elapsedTime();
ysr@777 4440 double elapsed_ms = (end_sec - start_sec) * 1000.0;
ysr@777 4441 non_young_time_ms += elapsed_ms;
ysr@777 4442
ysr@777 4443 start_sec = os::elapsedTime();
ysr@777 4444 non_young = false;
ysr@777 4445 }
ysr@777 4446 } else {
ysr@777 4447 if (!cur->is_on_free_list()) {
ysr@777 4448 double end_sec = os::elapsedTime();
ysr@777 4449 double elapsed_ms = (end_sec - start_sec) * 1000.0;
ysr@777 4450 young_time_ms += elapsed_ms;
ysr@777 4451
ysr@777 4452 start_sec = os::elapsedTime();
ysr@777 4453 non_young = true;
ysr@777 4454 }
ysr@777 4455 }
ysr@777 4456
ysr@777 4457 rs_lengths += cur->rem_set()->occupied();
ysr@777 4458
ysr@777 4459 HeapRegion* next = cur->next_in_collection_set();
ysr@777 4460 assert(cur->in_collection_set(), "bad CS");
ysr@777 4461 cur->set_next_in_collection_set(NULL);
ysr@777 4462 cur->set_in_collection_set(false);
ysr@777 4463
ysr@777 4464 if (cur->is_young()) {
ysr@777 4465 int index = cur->young_index_in_cset();
ysr@777 4466 guarantee( index != -1, "invariant" );
ysr@777 4467 guarantee( (size_t)index < policy->young_cset_length(), "invariant" );
ysr@777 4468 size_t words_survived = _surviving_young_words[index];
ysr@777 4469 cur->record_surv_words_in_group(words_survived);
ysr@777 4470 } else {
ysr@777 4471 int index = cur->young_index_in_cset();
ysr@777 4472 guarantee( index == -1, "invariant" );
ysr@777 4473 }
ysr@777 4474
ysr@777 4475 assert( (cur->is_young() && cur->young_index_in_cset() > -1) ||
ysr@777 4476 (!cur->is_young() && cur->young_index_in_cset() == -1),
ysr@777 4477 "invariant" );
ysr@777 4478
ysr@777 4479 if (!cur->evacuation_failed()) {
ysr@777 4480 // And the region is empty.
ysr@777 4481 assert(!cur->is_empty(),
ysr@777 4482 "Should not have empty regions in a CS.");
ysr@777 4483 free_region(cur);
ysr@777 4484 } else {
ysr@777 4485 guarantee( !cur->is_scan_only(), "should not be scan only" );
ysr@777 4486 cur->uninstall_surv_rate_group();
ysr@777 4487 if (cur->is_young())
ysr@777 4488 cur->set_young_index_in_cset(-1);
ysr@777 4489 cur->set_not_young();
ysr@777 4490 cur->set_evacuation_failed(false);
ysr@777 4491 }
ysr@777 4492 cur = next;
ysr@777 4493 }
ysr@777 4494
ysr@777 4495 policy->record_max_rs_lengths(rs_lengths);
ysr@777 4496 policy->cset_regions_freed();
ysr@777 4497
ysr@777 4498 double end_sec = os::elapsedTime();
ysr@777 4499 double elapsed_ms = (end_sec - start_sec) * 1000.0;
ysr@777 4500 if (non_young)
ysr@777 4501 non_young_time_ms += elapsed_ms;
ysr@777 4502 else
ysr@777 4503 young_time_ms += elapsed_ms;
ysr@777 4504
ysr@777 4505 policy->record_young_free_cset_time_ms(young_time_ms);
ysr@777 4506 policy->record_non_young_free_cset_time_ms(non_young_time_ms);
ysr@777 4507 }
ysr@777 4508
ysr@777 4509 HeapRegion*
ysr@777 4510 G1CollectedHeap::alloc_region_from_unclean_list_locked(bool zero_filled) {
ysr@777 4511 assert(ZF_mon->owned_by_self(), "Precondition");
ysr@777 4512 HeapRegion* res = pop_unclean_region_list_locked();
ysr@777 4513 if (res != NULL) {
ysr@777 4514 assert(!res->continuesHumongous() &&
ysr@777 4515 res->zero_fill_state() != HeapRegion::Allocated,
ysr@777 4516 "Only free regions on unclean list.");
ysr@777 4517 if (zero_filled) {
ysr@777 4518 res->ensure_zero_filled_locked();
ysr@777 4519 res->set_zero_fill_allocated();
ysr@777 4520 }
ysr@777 4521 }
ysr@777 4522 return res;
ysr@777 4523 }
ysr@777 4524
ysr@777 4525 HeapRegion* G1CollectedHeap::alloc_region_from_unclean_list(bool zero_filled) {
ysr@777 4526 MutexLockerEx zx(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 4527 return alloc_region_from_unclean_list_locked(zero_filled);
ysr@777 4528 }
ysr@777 4529
ysr@777 4530 void G1CollectedHeap::put_region_on_unclean_list(HeapRegion* r) {
ysr@777 4531 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 4532 put_region_on_unclean_list_locked(r);
ysr@777 4533 if (should_zf()) ZF_mon->notify_all(); // Wake up ZF thread.
ysr@777 4534 }
ysr@777 4535
ysr@777 4536 void G1CollectedHeap::set_unclean_regions_coming(bool b) {
ysr@777 4537 MutexLockerEx x(Cleanup_mon);
ysr@777 4538 set_unclean_regions_coming_locked(b);
ysr@777 4539 }
ysr@777 4540
ysr@777 4541 void G1CollectedHeap::set_unclean_regions_coming_locked(bool b) {
ysr@777 4542 assert(Cleanup_mon->owned_by_self(), "Precondition");
ysr@777 4543 _unclean_regions_coming = b;
ysr@777 4544 // Wake up mutator threads that might be waiting for completeCleanup to
ysr@777 4545 // finish.
ysr@777 4546 if (!b) Cleanup_mon->notify_all();
ysr@777 4547 }
ysr@777 4548
ysr@777 4549 void G1CollectedHeap::wait_for_cleanup_complete() {
ysr@777 4550 MutexLockerEx x(Cleanup_mon);
ysr@777 4551 wait_for_cleanup_complete_locked();
ysr@777 4552 }
ysr@777 4553
ysr@777 4554 void G1CollectedHeap::wait_for_cleanup_complete_locked() {
ysr@777 4555 assert(Cleanup_mon->owned_by_self(), "precondition");
ysr@777 4556 while (_unclean_regions_coming) {
ysr@777 4557 Cleanup_mon->wait();
ysr@777 4558 }
ysr@777 4559 }
ysr@777 4560
ysr@777 4561 void
ysr@777 4562 G1CollectedHeap::put_region_on_unclean_list_locked(HeapRegion* r) {
ysr@777 4563 assert(ZF_mon->owned_by_self(), "precondition.");
ysr@777 4564 _unclean_region_list.insert_before_head(r);
ysr@777 4565 }
ysr@777 4566
ysr@777 4567 void
ysr@777 4568 G1CollectedHeap::prepend_region_list_on_unclean_list(UncleanRegionList* list) {
ysr@777 4569 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 4570 prepend_region_list_on_unclean_list_locked(list);
ysr@777 4571 if (should_zf()) ZF_mon->notify_all(); // Wake up ZF thread.
ysr@777 4572 }
ysr@777 4573
ysr@777 4574 void
ysr@777 4575 G1CollectedHeap::
ysr@777 4576 prepend_region_list_on_unclean_list_locked(UncleanRegionList* list) {
ysr@777 4577 assert(ZF_mon->owned_by_self(), "precondition.");
ysr@777 4578 _unclean_region_list.prepend_list(list);
ysr@777 4579 }
ysr@777 4580
ysr@777 4581 HeapRegion* G1CollectedHeap::pop_unclean_region_list_locked() {
ysr@777 4582 assert(ZF_mon->owned_by_self(), "precondition.");
ysr@777 4583 HeapRegion* res = _unclean_region_list.pop();
ysr@777 4584 if (res != NULL) {
ysr@777 4585 // Inform ZF thread that there's a new unclean head.
ysr@777 4586 if (_unclean_region_list.hd() != NULL && should_zf())
ysr@777 4587 ZF_mon->notify_all();
ysr@777 4588 }
ysr@777 4589 return res;
ysr@777 4590 }
ysr@777 4591
ysr@777 4592 HeapRegion* G1CollectedHeap::peek_unclean_region_list_locked() {
ysr@777 4593 assert(ZF_mon->owned_by_self(), "precondition.");
ysr@777 4594 return _unclean_region_list.hd();
ysr@777 4595 }
ysr@777 4596
ysr@777 4597
ysr@777 4598 bool G1CollectedHeap::move_cleaned_region_to_free_list_locked() {
ysr@777 4599 assert(ZF_mon->owned_by_self(), "Precondition");
ysr@777 4600 HeapRegion* r = peek_unclean_region_list_locked();
ysr@777 4601 if (r != NULL && r->zero_fill_state() == HeapRegion::ZeroFilled) {
ysr@777 4602 // Result of below must be equal to "r", since we hold the lock.
ysr@777 4603 (void)pop_unclean_region_list_locked();
ysr@777 4604 put_free_region_on_list_locked(r);
ysr@777 4605 return true;
ysr@777 4606 } else {
ysr@777 4607 return false;
ysr@777 4608 }
ysr@777 4609 }
ysr@777 4610
ysr@777 4611 bool G1CollectedHeap::move_cleaned_region_to_free_list() {
ysr@777 4612 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 4613 return move_cleaned_region_to_free_list_locked();
ysr@777 4614 }
ysr@777 4615
ysr@777 4616
ysr@777 4617 void G1CollectedHeap::put_free_region_on_list_locked(HeapRegion* r) {
ysr@777 4618 assert(ZF_mon->owned_by_self(), "precondition.");
ysr@777 4619 assert(_free_region_list_size == free_region_list_length(), "Inv");
ysr@777 4620 assert(r->zero_fill_state() == HeapRegion::ZeroFilled,
ysr@777 4621 "Regions on free list must be zero filled");
ysr@777 4622 assert(!r->isHumongous(), "Must not be humongous.");
ysr@777 4623 assert(r->is_empty(), "Better be empty");
ysr@777 4624 assert(!r->is_on_free_list(),
ysr@777 4625 "Better not already be on free list");
ysr@777 4626 assert(!r->is_on_unclean_list(),
ysr@777 4627 "Better not already be on unclean list");
ysr@777 4628 r->set_on_free_list(true);
ysr@777 4629 r->set_next_on_free_list(_free_region_list);
ysr@777 4630 _free_region_list = r;
ysr@777 4631 _free_region_list_size++;
ysr@777 4632 assert(_free_region_list_size == free_region_list_length(), "Inv");
ysr@777 4633 }
ysr@777 4634
ysr@777 4635 void G1CollectedHeap::put_free_region_on_list(HeapRegion* r) {
ysr@777 4636 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 4637 put_free_region_on_list_locked(r);
ysr@777 4638 }
ysr@777 4639
ysr@777 4640 HeapRegion* G1CollectedHeap::pop_free_region_list_locked() {
ysr@777 4641 assert(ZF_mon->owned_by_self(), "precondition.");
ysr@777 4642 assert(_free_region_list_size == free_region_list_length(), "Inv");
ysr@777 4643 HeapRegion* res = _free_region_list;
ysr@777 4644 if (res != NULL) {
ysr@777 4645 _free_region_list = res->next_from_free_list();
ysr@777 4646 _free_region_list_size--;
ysr@777 4647 res->set_on_free_list(false);
ysr@777 4648 res->set_next_on_free_list(NULL);
ysr@777 4649 assert(_free_region_list_size == free_region_list_length(), "Inv");
ysr@777 4650 }
ysr@777 4651 return res;
ysr@777 4652 }
ysr@777 4653
ysr@777 4654
ysr@777 4655 HeapRegion* G1CollectedHeap::alloc_free_region_from_lists(bool zero_filled) {
ysr@777 4656 // By self, or on behalf of self.
ysr@777 4657 assert(Heap_lock->is_locked(), "Precondition");
ysr@777 4658 HeapRegion* res = NULL;
ysr@777 4659 bool first = true;
ysr@777 4660 while (res == NULL) {
ysr@777 4661 if (zero_filled || !first) {
ysr@777 4662 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 4663 res = pop_free_region_list_locked();
ysr@777 4664 if (res != NULL) {
ysr@777 4665 assert(!res->zero_fill_is_allocated(),
ysr@777 4666 "No allocated regions on free list.");
ysr@777 4667 res->set_zero_fill_allocated();
ysr@777 4668 } else if (!first) {
ysr@777 4669 break; // We tried both, time to return NULL.
ysr@777 4670 }
ysr@777 4671 }
ysr@777 4672
ysr@777 4673 if (res == NULL) {
ysr@777 4674 res = alloc_region_from_unclean_list(zero_filled);
ysr@777 4675 }
ysr@777 4676 assert(res == NULL ||
ysr@777 4677 !zero_filled ||
ysr@777 4678 res->zero_fill_is_allocated(),
ysr@777 4679 "We must have allocated the region we're returning");
ysr@777 4680 first = false;
ysr@777 4681 }
ysr@777 4682 return res;
ysr@777 4683 }
ysr@777 4684
ysr@777 4685 void G1CollectedHeap::remove_allocated_regions_from_lists() {
ysr@777 4686 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 4687 {
ysr@777 4688 HeapRegion* prev = NULL;
ysr@777 4689 HeapRegion* cur = _unclean_region_list.hd();
ysr@777 4690 while (cur != NULL) {
ysr@777 4691 HeapRegion* next = cur->next_from_unclean_list();
ysr@777 4692 if (cur->zero_fill_is_allocated()) {
ysr@777 4693 // Remove from the list.
ysr@777 4694 if (prev == NULL) {
ysr@777 4695 (void)_unclean_region_list.pop();
ysr@777 4696 } else {
ysr@777 4697 _unclean_region_list.delete_after(prev);
ysr@777 4698 }
ysr@777 4699 cur->set_on_unclean_list(false);
ysr@777 4700 cur->set_next_on_unclean_list(NULL);
ysr@777 4701 } else {
ysr@777 4702 prev = cur;
ysr@777 4703 }
ysr@777 4704 cur = next;
ysr@777 4705 }
ysr@777 4706 assert(_unclean_region_list.sz() == unclean_region_list_length(),
ysr@777 4707 "Inv");
ysr@777 4708 }
ysr@777 4709
ysr@777 4710 {
ysr@777 4711 HeapRegion* prev = NULL;
ysr@777 4712 HeapRegion* cur = _free_region_list;
ysr@777 4713 while (cur != NULL) {
ysr@777 4714 HeapRegion* next = cur->next_from_free_list();
ysr@777 4715 if (cur->zero_fill_is_allocated()) {
ysr@777 4716 // Remove from the list.
ysr@777 4717 if (prev == NULL) {
ysr@777 4718 _free_region_list = cur->next_from_free_list();
ysr@777 4719 } else {
ysr@777 4720 prev->set_next_on_free_list(cur->next_from_free_list());
ysr@777 4721 }
ysr@777 4722 cur->set_on_free_list(false);
ysr@777 4723 cur->set_next_on_free_list(NULL);
ysr@777 4724 _free_region_list_size--;
ysr@777 4725 } else {
ysr@777 4726 prev = cur;
ysr@777 4727 }
ysr@777 4728 cur = next;
ysr@777 4729 }
ysr@777 4730 assert(_free_region_list_size == free_region_list_length(), "Inv");
ysr@777 4731 }
ysr@777 4732 }
ysr@777 4733
ysr@777 4734 bool G1CollectedHeap::verify_region_lists() {
ysr@777 4735 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 4736 return verify_region_lists_locked();
ysr@777 4737 }
ysr@777 4738
ysr@777 4739 bool G1CollectedHeap::verify_region_lists_locked() {
ysr@777 4740 HeapRegion* unclean = _unclean_region_list.hd();
ysr@777 4741 while (unclean != NULL) {
ysr@777 4742 guarantee(unclean->is_on_unclean_list(), "Well, it is!");
ysr@777 4743 guarantee(!unclean->is_on_free_list(), "Well, it shouldn't be!");
ysr@777 4744 guarantee(unclean->zero_fill_state() != HeapRegion::Allocated,
ysr@777 4745 "Everything else is possible.");
ysr@777 4746 unclean = unclean->next_from_unclean_list();
ysr@777 4747 }
ysr@777 4748 guarantee(_unclean_region_list.sz() == unclean_region_list_length(), "Inv");
ysr@777 4749
ysr@777 4750 HeapRegion* free_r = _free_region_list;
ysr@777 4751 while (free_r != NULL) {
ysr@777 4752 assert(free_r->is_on_free_list(), "Well, it is!");
ysr@777 4753 assert(!free_r->is_on_unclean_list(), "Well, it shouldn't be!");
ysr@777 4754 switch (free_r->zero_fill_state()) {
ysr@777 4755 case HeapRegion::NotZeroFilled:
ysr@777 4756 case HeapRegion::ZeroFilling:
ysr@777 4757 guarantee(false, "Should not be on free list.");
ysr@777 4758 break;
ysr@777 4759 default:
ysr@777 4760 // Everything else is possible.
ysr@777 4761 break;
ysr@777 4762 }
ysr@777 4763 free_r = free_r->next_from_free_list();
ysr@777 4764 }
ysr@777 4765 guarantee(_free_region_list_size == free_region_list_length(), "Inv");
ysr@777 4766 // If we didn't do an assertion...
ysr@777 4767 return true;
ysr@777 4768 }
ysr@777 4769
ysr@777 4770 size_t G1CollectedHeap::free_region_list_length() {
ysr@777 4771 assert(ZF_mon->owned_by_self(), "precondition.");
ysr@777 4772 size_t len = 0;
ysr@777 4773 HeapRegion* cur = _free_region_list;
ysr@777 4774 while (cur != NULL) {
ysr@777 4775 len++;
ysr@777 4776 cur = cur->next_from_free_list();
ysr@777 4777 }
ysr@777 4778 return len;
ysr@777 4779 }
ysr@777 4780
ysr@777 4781 size_t G1CollectedHeap::unclean_region_list_length() {
ysr@777 4782 assert(ZF_mon->owned_by_self(), "precondition.");
ysr@777 4783 return _unclean_region_list.length();
ysr@777 4784 }
ysr@777 4785
ysr@777 4786 size_t G1CollectedHeap::n_regions() {
ysr@777 4787 return _hrs->length();
ysr@777 4788 }
ysr@777 4789
ysr@777 4790 size_t G1CollectedHeap::max_regions() {
ysr@777 4791 return
ysr@777 4792 (size_t)align_size_up(g1_reserved_obj_bytes(), HeapRegion::GrainBytes) /
ysr@777 4793 HeapRegion::GrainBytes;
ysr@777 4794 }
ysr@777 4795
ysr@777 4796 size_t G1CollectedHeap::free_regions() {
ysr@777 4797 /* Possibly-expensive assert.
ysr@777 4798 assert(_free_regions == count_free_regions(),
ysr@777 4799 "_free_regions is off.");
ysr@777 4800 */
ysr@777 4801 return _free_regions;
ysr@777 4802 }
ysr@777 4803
ysr@777 4804 bool G1CollectedHeap::should_zf() {
ysr@777 4805 return _free_region_list_size < (size_t) G1ConcZFMaxRegions;
ysr@777 4806 }
ysr@777 4807
ysr@777 4808 class RegionCounter: public HeapRegionClosure {
ysr@777 4809 size_t _n;
ysr@777 4810 public:
ysr@777 4811 RegionCounter() : _n(0) {}
ysr@777 4812 bool doHeapRegion(HeapRegion* r) {
ysr@777 4813 if (r->is_empty() && !r->popular()) {
ysr@777 4814 assert(!r->isHumongous(), "H regions should not be empty.");
ysr@777 4815 _n++;
ysr@777 4816 }
ysr@777 4817 return false;
ysr@777 4818 }
ysr@777 4819 int res() { return (int) _n; }
ysr@777 4820 };
ysr@777 4821
ysr@777 4822 size_t G1CollectedHeap::count_free_regions() {
ysr@777 4823 RegionCounter rc;
ysr@777 4824 heap_region_iterate(&rc);
ysr@777 4825 size_t n = rc.res();
ysr@777 4826 if (_cur_alloc_region != NULL && _cur_alloc_region->is_empty())
ysr@777 4827 n--;
ysr@777 4828 return n;
ysr@777 4829 }
ysr@777 4830
ysr@777 4831 size_t G1CollectedHeap::count_free_regions_list() {
ysr@777 4832 size_t n = 0;
ysr@777 4833 size_t o = 0;
ysr@777 4834 ZF_mon->lock_without_safepoint_check();
ysr@777 4835 HeapRegion* cur = _free_region_list;
ysr@777 4836 while (cur != NULL) {
ysr@777 4837 cur = cur->next_from_free_list();
ysr@777 4838 n++;
ysr@777 4839 }
ysr@777 4840 size_t m = unclean_region_list_length();
ysr@777 4841 ZF_mon->unlock();
ysr@777 4842 return n + m;
ysr@777 4843 }
ysr@777 4844
ysr@777 4845 bool G1CollectedHeap::should_set_young_locked() {
ysr@777 4846 assert(heap_lock_held_for_gc(),
ysr@777 4847 "the heap lock should already be held by or for this thread");
ysr@777 4848 return (g1_policy()->in_young_gc_mode() &&
ysr@777 4849 g1_policy()->should_add_next_region_to_young_list());
ysr@777 4850 }
ysr@777 4851
ysr@777 4852 void G1CollectedHeap::set_region_short_lived_locked(HeapRegion* hr) {
ysr@777 4853 assert(heap_lock_held_for_gc(),
ysr@777 4854 "the heap lock should already be held by or for this thread");
ysr@777 4855 _young_list->push_region(hr);
ysr@777 4856 g1_policy()->set_region_short_lived(hr);
ysr@777 4857 }
ysr@777 4858
ysr@777 4859 class NoYoungRegionsClosure: public HeapRegionClosure {
ysr@777 4860 private:
ysr@777 4861 bool _success;
ysr@777 4862 public:
ysr@777 4863 NoYoungRegionsClosure() : _success(true) { }
ysr@777 4864 bool doHeapRegion(HeapRegion* r) {
ysr@777 4865 if (r->is_young()) {
ysr@777 4866 gclog_or_tty->print_cr("Region ["PTR_FORMAT", "PTR_FORMAT") tagged as young",
ysr@777 4867 r->bottom(), r->end());
ysr@777 4868 _success = false;
ysr@777 4869 }
ysr@777 4870 return false;
ysr@777 4871 }
ysr@777 4872 bool success() { return _success; }
ysr@777 4873 };
ysr@777 4874
ysr@777 4875 bool G1CollectedHeap::check_young_list_empty(bool ignore_scan_only_list,
ysr@777 4876 bool check_sample) {
ysr@777 4877 bool ret = true;
ysr@777 4878
ysr@777 4879 ret = _young_list->check_list_empty(ignore_scan_only_list, check_sample);
ysr@777 4880 if (!ignore_scan_only_list) {
ysr@777 4881 NoYoungRegionsClosure closure;
ysr@777 4882 heap_region_iterate(&closure);
ysr@777 4883 ret = ret && closure.success();
ysr@777 4884 }
ysr@777 4885
ysr@777 4886 return ret;
ysr@777 4887 }
ysr@777 4888
ysr@777 4889 void G1CollectedHeap::empty_young_list() {
ysr@777 4890 assert(heap_lock_held_for_gc(),
ysr@777 4891 "the heap lock should already be held by or for this thread");
ysr@777 4892 assert(g1_policy()->in_young_gc_mode(), "should be in young GC mode");
ysr@777 4893
ysr@777 4894 _young_list->empty_list();
ysr@777 4895 }
ysr@777 4896
ysr@777 4897 bool G1CollectedHeap::all_alloc_regions_no_allocs_since_save_marks() {
ysr@777 4898 bool no_allocs = true;
ysr@777 4899 for (int ap = 0; ap < GCAllocPurposeCount && no_allocs; ++ap) {
ysr@777 4900 HeapRegion* r = _gc_alloc_regions[ap];
ysr@777 4901 no_allocs = r == NULL || r->saved_mark_at_top();
ysr@777 4902 }
ysr@777 4903 return no_allocs;
ysr@777 4904 }
ysr@777 4905
ysr@777 4906 void G1CollectedHeap::all_alloc_regions_note_end_of_copying() {
ysr@777 4907 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) {
ysr@777 4908 HeapRegion* r = _gc_alloc_regions[ap];
ysr@777 4909 if (r != NULL) {
ysr@777 4910 // Check for aliases.
ysr@777 4911 bool has_processed_alias = false;
ysr@777 4912 for (int i = 0; i < ap; ++i) {
ysr@777 4913 if (_gc_alloc_regions[i] == r) {
ysr@777 4914 has_processed_alias = true;
ysr@777 4915 break;
ysr@777 4916 }
ysr@777 4917 }
ysr@777 4918 if (!has_processed_alias) {
ysr@777 4919 r->note_end_of_copying();
ysr@777 4920 g1_policy()->record_after_bytes(r->used());
ysr@777 4921 }
ysr@777 4922 }
ysr@777 4923 }
ysr@777 4924 }
ysr@777 4925
ysr@777 4926
ysr@777 4927 // Done at the start of full GC.
ysr@777 4928 void G1CollectedHeap::tear_down_region_lists() {
ysr@777 4929 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 4930 while (pop_unclean_region_list_locked() != NULL) ;
ysr@777 4931 assert(_unclean_region_list.hd() == NULL && _unclean_region_list.sz() == 0,
ysr@777 4932 "Postconditions of loop.")
ysr@777 4933 while (pop_free_region_list_locked() != NULL) ;
ysr@777 4934 assert(_free_region_list == NULL, "Postcondition of loop.");
ysr@777 4935 if (_free_region_list_size != 0) {
ysr@777 4936 gclog_or_tty->print_cr("Size is %d.", _free_region_list_size);
ysr@777 4937 print();
ysr@777 4938 }
ysr@777 4939 assert(_free_region_list_size == 0, "Postconditions of loop.");
ysr@777 4940 }
ysr@777 4941
ysr@777 4942
ysr@777 4943 class RegionResetter: public HeapRegionClosure {
ysr@777 4944 G1CollectedHeap* _g1;
ysr@777 4945 int _n;
ysr@777 4946 public:
ysr@777 4947 RegionResetter() : _g1(G1CollectedHeap::heap()), _n(0) {}
ysr@777 4948 bool doHeapRegion(HeapRegion* r) {
ysr@777 4949 if (r->continuesHumongous()) return false;
ysr@777 4950 if (r->top() > r->bottom()) {
ysr@777 4951 if (r->top() < r->end()) {
ysr@777 4952 Copy::fill_to_words(r->top(),
ysr@777 4953 pointer_delta(r->end(), r->top()));
ysr@777 4954 }
ysr@777 4955 r->set_zero_fill_allocated();
ysr@777 4956 } else {
ysr@777 4957 assert(r->is_empty(), "tautology");
ysr@777 4958 if (r->popular()) {
ysr@777 4959 if (r->zero_fill_state() != HeapRegion::Allocated) {
ysr@777 4960 r->ensure_zero_filled_locked();
ysr@777 4961 r->set_zero_fill_allocated();
ysr@777 4962 }
ysr@777 4963 } else {
ysr@777 4964 _n++;
ysr@777 4965 switch (r->zero_fill_state()) {
ysr@777 4966 case HeapRegion::NotZeroFilled:
ysr@777 4967 case HeapRegion::ZeroFilling:
ysr@777 4968 _g1->put_region_on_unclean_list_locked(r);
ysr@777 4969 break;
ysr@777 4970 case HeapRegion::Allocated:
ysr@777 4971 r->set_zero_fill_complete();
ysr@777 4972 // no break; go on to put on free list.
ysr@777 4973 case HeapRegion::ZeroFilled:
ysr@777 4974 _g1->put_free_region_on_list_locked(r);
ysr@777 4975 break;
ysr@777 4976 }
ysr@777 4977 }
ysr@777 4978 }
ysr@777 4979 return false;
ysr@777 4980 }
ysr@777 4981
ysr@777 4982 int getFreeRegionCount() {return _n;}
ysr@777 4983 };
ysr@777 4984
ysr@777 4985 // Done at the end of full GC.
ysr@777 4986 void G1CollectedHeap::rebuild_region_lists() {
ysr@777 4987 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 4988 // This needs to go at the end of the full GC.
ysr@777 4989 RegionResetter rs;
ysr@777 4990 heap_region_iterate(&rs);
ysr@777 4991 _free_regions = rs.getFreeRegionCount();
ysr@777 4992 // Tell the ZF thread it may have work to do.
ysr@777 4993 if (should_zf()) ZF_mon->notify_all();
ysr@777 4994 }
ysr@777 4995
ysr@777 4996 class UsedRegionsNeedZeroFillSetter: public HeapRegionClosure {
ysr@777 4997 G1CollectedHeap* _g1;
ysr@777 4998 int _n;
ysr@777 4999 public:
ysr@777 5000 UsedRegionsNeedZeroFillSetter() : _g1(G1CollectedHeap::heap()), _n(0) {}
ysr@777 5001 bool doHeapRegion(HeapRegion* r) {
ysr@777 5002 if (r->continuesHumongous()) return false;
ysr@777 5003 if (r->top() > r->bottom()) {
ysr@777 5004 // There are assertions in "set_zero_fill_needed()" below that
ysr@777 5005 // require top() == bottom(), so this is technically illegal.
ysr@777 5006 // We'll skirt the law here, by making that true temporarily.
ysr@777 5007 DEBUG_ONLY(HeapWord* save_top = r->top();
ysr@777 5008 r->set_top(r->bottom()));
ysr@777 5009 r->set_zero_fill_needed();
ysr@777 5010 DEBUG_ONLY(r->set_top(save_top));
ysr@777 5011 }
ysr@777 5012 return false;
ysr@777 5013 }
ysr@777 5014 };
ysr@777 5015
ysr@777 5016 // Done at the start of full GC.
ysr@777 5017 void G1CollectedHeap::set_used_regions_to_need_zero_fill() {
ysr@777 5018 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777 5019 // This needs to go at the end of the full GC.
ysr@777 5020 UsedRegionsNeedZeroFillSetter rs;
ysr@777 5021 heap_region_iterate(&rs);
ysr@777 5022 }
ysr@777 5023
ysr@777 5024 class CountObjClosure: public ObjectClosure {
ysr@777 5025 size_t _n;
ysr@777 5026 public:
ysr@777 5027 CountObjClosure() : _n(0) {}
ysr@777 5028 void do_object(oop obj) { _n++; }
ysr@777 5029 size_t n() { return _n; }
ysr@777 5030 };
ysr@777 5031
ysr@777 5032 size_t G1CollectedHeap::pop_object_used_objs() {
ysr@777 5033 size_t sum_objs = 0;
ysr@777 5034 for (int i = 0; i < G1NumPopularRegions; i++) {
ysr@777 5035 CountObjClosure cl;
ysr@777 5036 _hrs->at(i)->object_iterate(&cl);
ysr@777 5037 sum_objs += cl.n();
ysr@777 5038 }
ysr@777 5039 return sum_objs;
ysr@777 5040 }
ysr@777 5041
ysr@777 5042 size_t G1CollectedHeap::pop_object_used_bytes() {
ysr@777 5043 size_t sum_bytes = 0;
ysr@777 5044 for (int i = 0; i < G1NumPopularRegions; i++) {
ysr@777 5045 sum_bytes += _hrs->at(i)->used();
ysr@777 5046 }
ysr@777 5047 return sum_bytes;
ysr@777 5048 }
ysr@777 5049
ysr@777 5050
ysr@777 5051 static int nq = 0;
ysr@777 5052
ysr@777 5053 HeapWord* G1CollectedHeap::allocate_popular_object(size_t word_size) {
ysr@777 5054 while (_cur_pop_hr_index < G1NumPopularRegions) {
ysr@777 5055 HeapRegion* cur_pop_region = _hrs->at(_cur_pop_hr_index);
ysr@777 5056 HeapWord* res = cur_pop_region->allocate(word_size);
ysr@777 5057 if (res != NULL) {
ysr@777 5058 // We account for popular objs directly in the used summary:
ysr@777 5059 _summary_bytes_used += (word_size * HeapWordSize);
ysr@777 5060 return res;
ysr@777 5061 }
ysr@777 5062 // Otherwise, try the next region (first making sure that we remember
ysr@777 5063 // the last "top" value as the "next_top_at_mark_start", so that
ysr@777 5064 // objects made popular during markings aren't automatically considered
ysr@777 5065 // live).
ysr@777 5066 cur_pop_region->note_end_of_copying();
ysr@777 5067 // Otherwise, try the next region.
ysr@777 5068 _cur_pop_hr_index++;
ysr@777 5069 }
ysr@777 5070 // XXX: For now !!!
ysr@777 5071 vm_exit_out_of_memory(word_size,
ysr@777 5072 "Not enough pop obj space (To Be Fixed)");
ysr@777 5073 return NULL;
ysr@777 5074 }
ysr@777 5075
ysr@777 5076 class HeapRegionList: public CHeapObj {
ysr@777 5077 public:
ysr@777 5078 HeapRegion* hr;
ysr@777 5079 HeapRegionList* next;
ysr@777 5080 };
ysr@777 5081
ysr@777 5082 void G1CollectedHeap::schedule_popular_region_evac(HeapRegion* r) {
ysr@777 5083 // This might happen during parallel GC, so protect by this lock.
ysr@777 5084 MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag);
ysr@777 5085 // We don't schedule regions whose evacuations are already pending, or
ysr@777 5086 // are already being evacuated.
ysr@777 5087 if (!r->popular_pending() && !r->in_collection_set()) {
ysr@777 5088 r->set_popular_pending(true);
ysr@777 5089 if (G1TracePopularity) {
ysr@777 5090 gclog_or_tty->print_cr("Scheduling region "PTR_FORMAT" "
ysr@777 5091 "["PTR_FORMAT", "PTR_FORMAT") for pop-object evacuation.",
ysr@777 5092 r, r->bottom(), r->end());
ysr@777 5093 }
ysr@777 5094 HeapRegionList* hrl = new HeapRegionList;
ysr@777 5095 hrl->hr = r;
ysr@777 5096 hrl->next = _popular_regions_to_be_evacuated;
ysr@777 5097 _popular_regions_to_be_evacuated = hrl;
ysr@777 5098 }
ysr@777 5099 }
ysr@777 5100
ysr@777 5101 HeapRegion* G1CollectedHeap::popular_region_to_evac() {
ysr@777 5102 MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag);
ysr@777 5103 HeapRegion* res = NULL;
ysr@777 5104 while (_popular_regions_to_be_evacuated != NULL && res == NULL) {
ysr@777 5105 HeapRegionList* hrl = _popular_regions_to_be_evacuated;
ysr@777 5106 _popular_regions_to_be_evacuated = hrl->next;
ysr@777 5107 res = hrl->hr;
ysr@777 5108 // The G1RSPopLimit may have increased, so recheck here...
ysr@777 5109 if (res->rem_set()->occupied() < (size_t) G1RSPopLimit) {
ysr@777 5110 // Hah: don't need to schedule.
ysr@777 5111 if (G1TracePopularity) {
ysr@777 5112 gclog_or_tty->print_cr("Unscheduling region "PTR_FORMAT" "
ysr@777 5113 "["PTR_FORMAT", "PTR_FORMAT") "
ysr@777 5114 "for pop-object evacuation (size %d < limit %d)",
ysr@777 5115 res, res->bottom(), res->end(),
ysr@777 5116 res->rem_set()->occupied(), G1RSPopLimit);
ysr@777 5117 }
ysr@777 5118 res->set_popular_pending(false);
ysr@777 5119 res = NULL;
ysr@777 5120 }
ysr@777 5121 // We do not reset res->popular() here; if we did so, it would allow
ysr@777 5122 // the region to be "rescheduled" for popularity evacuation. Instead,
ysr@777 5123 // this is done in the collection pause, with the world stopped.
ysr@777 5124 // So the invariant is that the regions in the list have the popularity
ysr@777 5125 // boolean set, but having the boolean set does not imply membership
ysr@777 5126 // on the list (though there can at most one such pop-pending region
ysr@777 5127 // not on the list at any time).
ysr@777 5128 delete hrl;
ysr@777 5129 }
ysr@777 5130 return res;
ysr@777 5131 }
ysr@777 5132
ysr@777 5133 void G1CollectedHeap::evac_popular_region(HeapRegion* hr) {
ysr@777 5134 while (true) {
ysr@777 5135 // Don't want to do a GC pause while cleanup is being completed!
ysr@777 5136 wait_for_cleanup_complete();
ysr@777 5137
ysr@777 5138 // Read the GC count while holding the Heap_lock
ysr@777 5139 int gc_count_before = SharedHeap::heap()->total_collections();
ysr@777 5140 g1_policy()->record_stop_world_start();
ysr@777 5141
ysr@777 5142 {
ysr@777 5143 MutexUnlocker mu(Heap_lock); // give up heap lock, execute gets it back
ysr@777 5144 VM_G1PopRegionCollectionPause op(gc_count_before, hr);
ysr@777 5145 VMThread::execute(&op);
ysr@777 5146
ysr@777 5147 // If the prolog succeeded, we didn't do a GC for this.
ysr@777 5148 if (op.prologue_succeeded()) break;
ysr@777 5149 }
ysr@777 5150 // Otherwise we didn't. We should recheck the size, though, since
ysr@777 5151 // the limit may have increased...
ysr@777 5152 if (hr->rem_set()->occupied() < (size_t) G1RSPopLimit) {
ysr@777 5153 hr->set_popular_pending(false);
ysr@777 5154 break;
ysr@777 5155 }
ysr@777 5156 }
ysr@777 5157 }
ysr@777 5158
ysr@777 5159 void G1CollectedHeap::atomic_inc_obj_rc(oop obj) {
ysr@777 5160 Atomic::inc(obj_rc_addr(obj));
ysr@777 5161 }
ysr@777 5162
ysr@777 5163 class CountRCClosure: public OopsInHeapRegionClosure {
ysr@777 5164 G1CollectedHeap* _g1h;
ysr@777 5165 bool _parallel;
ysr@777 5166 public:
ysr@777 5167 CountRCClosure(G1CollectedHeap* g1h) :
ysr@777 5168 _g1h(g1h), _parallel(ParallelGCThreads > 0)
ysr@777 5169 {}
ysr@777 5170 void do_oop(narrowOop* p) {
ysr@777 5171 guarantee(false, "NYI");
ysr@777 5172 }
ysr@777 5173 void do_oop(oop* p) {
ysr@777 5174 oop obj = *p;
ysr@777 5175 assert(obj != NULL, "Precondition.");
ysr@777 5176 if (_parallel) {
ysr@777 5177 // We go sticky at the limit to avoid excess contention.
ysr@777 5178 // If we want to track the actual RC's further, we'll need to keep a
ysr@777 5179 // per-thread hash table or something for the popular objects.
ysr@777 5180 if (_g1h->obj_rc(obj) < G1ObjPopLimit) {
ysr@777 5181 _g1h->atomic_inc_obj_rc(obj);
ysr@777 5182 }
ysr@777 5183 } else {
ysr@777 5184 _g1h->inc_obj_rc(obj);
ysr@777 5185 }
ysr@777 5186 }
ysr@777 5187 };
ysr@777 5188
ysr@777 5189 class EvacPopObjClosure: public ObjectClosure {
ysr@777 5190 G1CollectedHeap* _g1h;
ysr@777 5191 size_t _pop_objs;
ysr@777 5192 size_t _max_rc;
ysr@777 5193 public:
ysr@777 5194 EvacPopObjClosure(G1CollectedHeap* g1h) :
ysr@777 5195 _g1h(g1h), _pop_objs(0), _max_rc(0) {}
ysr@777 5196
ysr@777 5197 void do_object(oop obj) {
ysr@777 5198 size_t rc = _g1h->obj_rc(obj);
ysr@777 5199 _max_rc = MAX2(rc, _max_rc);
ysr@777 5200 if (rc >= (size_t) G1ObjPopLimit) {
ysr@777 5201 _g1h->_pop_obj_rc_at_copy.add((double)rc);
ysr@777 5202 size_t word_sz = obj->size();
ysr@777 5203 HeapWord* new_pop_loc = _g1h->allocate_popular_object(word_sz);
ysr@777 5204 oop new_pop_obj = (oop)new_pop_loc;
ysr@777 5205 Copy::aligned_disjoint_words((HeapWord*)obj, new_pop_loc, word_sz);
ysr@777 5206 obj->forward_to(new_pop_obj);
ysr@777 5207 G1ScanAndBalanceClosure scan_and_balance(_g1h);
ysr@777 5208 new_pop_obj->oop_iterate_backwards(&scan_and_balance);
ysr@777 5209 // preserve "next" mark bit if marking is in progress.
ysr@777 5210 if (_g1h->mark_in_progress() && !_g1h->is_obj_ill(obj)) {
ysr@777 5211 _g1h->concurrent_mark()->markAndGrayObjectIfNecessary(new_pop_obj);
ysr@777 5212 }
ysr@777 5213
ysr@777 5214 if (G1TracePopularity) {
ysr@777 5215 gclog_or_tty->print_cr("Found obj " PTR_FORMAT " of word size " SIZE_FORMAT
ysr@777 5216 " pop (%d), move to " PTR_FORMAT,
ysr@777 5217 (void*) obj, word_sz,
ysr@777 5218 _g1h->obj_rc(obj), (void*) new_pop_obj);
ysr@777 5219 }
ysr@777 5220 _pop_objs++;
ysr@777 5221 }
ysr@777 5222 }
ysr@777 5223 size_t pop_objs() { return _pop_objs; }
ysr@777 5224 size_t max_rc() { return _max_rc; }
ysr@777 5225 };
ysr@777 5226
ysr@777 5227 class G1ParCountRCTask : public AbstractGangTask {
ysr@777 5228 G1CollectedHeap* _g1h;
ysr@777 5229 BitMap _bm;
ysr@777 5230
ysr@777 5231 size_t getNCards() {
ysr@777 5232 return (_g1h->capacity() + G1BlockOffsetSharedArray::N_bytes - 1)
ysr@777 5233 / G1BlockOffsetSharedArray::N_bytes;
ysr@777 5234 }
ysr@777 5235 CountRCClosure _count_rc_closure;
ysr@777 5236 public:
ysr@777 5237 G1ParCountRCTask(G1CollectedHeap* g1h) :
ysr@777 5238 AbstractGangTask("G1 Par RC Count task"),
ysr@777 5239 _g1h(g1h), _bm(getNCards()), _count_rc_closure(g1h)
ysr@777 5240 {}
ysr@777 5241
ysr@777 5242 void work(int i) {
ysr@777 5243 ResourceMark rm;
ysr@777 5244 HandleMark hm;
ysr@777 5245 _g1h->g1_rem_set()->oops_into_collection_set_do(&_count_rc_closure, i);
ysr@777 5246 }
ysr@777 5247 };
ysr@777 5248
ysr@777 5249 void G1CollectedHeap::popularity_pause_preamble(HeapRegion* popular_region) {
ysr@777 5250 // We're evacuating a single region (for popularity).
ysr@777 5251 if (G1TracePopularity) {
ysr@777 5252 gclog_or_tty->print_cr("Doing pop region pause for ["PTR_FORMAT", "PTR_FORMAT")",
ysr@777 5253 popular_region->bottom(), popular_region->end());
ysr@777 5254 }
ysr@777 5255 g1_policy()->set_single_region_collection_set(popular_region);
ysr@777 5256 size_t max_rc;
ysr@777 5257 if (!compute_reference_counts_and_evac_popular(popular_region,
ysr@777 5258 &max_rc)) {
ysr@777 5259 // We didn't evacuate any popular objects.
ysr@777 5260 // We increase the RS popularity limit, to prevent this from
ysr@777 5261 // happening in the future.
ysr@777 5262 if (G1RSPopLimit < (1 << 30)) {
ysr@777 5263 G1RSPopLimit *= 2;
ysr@777 5264 }
ysr@777 5265 // For now, interesting enough for a message:
ysr@777 5266 #if 1
ysr@777 5267 gclog_or_tty->print_cr("In pop region pause for ["PTR_FORMAT", "PTR_FORMAT"), "
ysr@777 5268 "failed to find a pop object (max = %d).",
ysr@777 5269 popular_region->bottom(), popular_region->end(),
ysr@777 5270 max_rc);
ysr@777 5271 gclog_or_tty->print_cr("Increased G1RSPopLimit to %d.", G1RSPopLimit);
ysr@777 5272 #endif // 0
ysr@777 5273 // Also, we reset the collection set to NULL, to make the rest of
ysr@777 5274 // the collection do nothing.
ysr@777 5275 assert(popular_region->next_in_collection_set() == NULL,
ysr@777 5276 "should be single-region.");
ysr@777 5277 popular_region->set_in_collection_set(false);
ysr@777 5278 popular_region->set_popular_pending(false);
ysr@777 5279 g1_policy()->clear_collection_set();
ysr@777 5280 }
ysr@777 5281 }
ysr@777 5282
ysr@777 5283 bool G1CollectedHeap::
ysr@777 5284 compute_reference_counts_and_evac_popular(HeapRegion* popular_region,
ysr@777 5285 size_t* max_rc) {
ysr@777 5286 HeapWord* rc_region_bot;
ysr@777 5287 HeapWord* rc_region_end;
ysr@777 5288
ysr@777 5289 // Set up the reference count region.
ysr@777 5290 HeapRegion* rc_region = newAllocRegion(HeapRegion::GrainWords);
ysr@777 5291 if (rc_region != NULL) {
ysr@777 5292 rc_region_bot = rc_region->bottom();
ysr@777 5293 rc_region_end = rc_region->end();
ysr@777 5294 } else {
ysr@777 5295 rc_region_bot = NEW_C_HEAP_ARRAY(HeapWord, HeapRegion::GrainWords);
ysr@777 5296 if (rc_region_bot == NULL) {
ysr@777 5297 vm_exit_out_of_memory(HeapRegion::GrainWords,
ysr@777 5298 "No space for RC region.");
ysr@777 5299 }
ysr@777 5300 rc_region_end = rc_region_bot + HeapRegion::GrainWords;
ysr@777 5301 }
ysr@777 5302
ysr@777 5303 if (G1TracePopularity)
ysr@777 5304 gclog_or_tty->print_cr("RC region is ["PTR_FORMAT", "PTR_FORMAT")",
ysr@777 5305 rc_region_bot, rc_region_end);
ysr@777 5306 if (rc_region_bot > popular_region->bottom()) {
ysr@777 5307 _rc_region_above = true;
ysr@777 5308 _rc_region_diff =
ysr@777 5309 pointer_delta(rc_region_bot, popular_region->bottom(), 1);
ysr@777 5310 } else {
ysr@777 5311 assert(rc_region_bot < popular_region->bottom(), "Can't be equal.");
ysr@777 5312 _rc_region_above = false;
ysr@777 5313 _rc_region_diff =
ysr@777 5314 pointer_delta(popular_region->bottom(), rc_region_bot, 1);
ysr@777 5315 }
ysr@777 5316 g1_policy()->record_pop_compute_rc_start();
ysr@777 5317 // Count external references.
ysr@777 5318 g1_rem_set()->prepare_for_oops_into_collection_set_do();
ysr@777 5319 if (ParallelGCThreads > 0) {
ysr@777 5320
ysr@777 5321 set_par_threads(workers()->total_workers());
ysr@777 5322 G1ParCountRCTask par_count_rc_task(this);
ysr@777 5323 workers()->run_task(&par_count_rc_task);
ysr@777 5324 set_par_threads(0);
ysr@777 5325
ysr@777 5326 } else {
ysr@777 5327 CountRCClosure count_rc_closure(this);
ysr@777 5328 g1_rem_set()->oops_into_collection_set_do(&count_rc_closure, 0);
ysr@777 5329 }
ysr@777 5330 g1_rem_set()->cleanup_after_oops_into_collection_set_do();
ysr@777 5331 g1_policy()->record_pop_compute_rc_end();
ysr@777 5332
ysr@777 5333 // Now evacuate popular objects.
ysr@777 5334 g1_policy()->record_pop_evac_start();
ysr@777 5335 EvacPopObjClosure evac_pop_obj_cl(this);
ysr@777 5336 popular_region->object_iterate(&evac_pop_obj_cl);
ysr@777 5337 *max_rc = evac_pop_obj_cl.max_rc();
ysr@777 5338
ysr@777 5339 // Make sure the last "top" value of the current popular region is copied
ysr@777 5340 // as the "next_top_at_mark_start", so that objects made popular during
ysr@777 5341 // markings aren't automatically considered live.
ysr@777 5342 HeapRegion* cur_pop_region = _hrs->at(_cur_pop_hr_index);
ysr@777 5343 cur_pop_region->note_end_of_copying();
ysr@777 5344
ysr@777 5345 if (rc_region != NULL) {
ysr@777 5346 free_region(rc_region);
ysr@777 5347 } else {
ysr@777 5348 FREE_C_HEAP_ARRAY(HeapWord, rc_region_bot);
ysr@777 5349 }
ysr@777 5350 g1_policy()->record_pop_evac_end();
ysr@777 5351
ysr@777 5352 return evac_pop_obj_cl.pop_objs() > 0;
ysr@777 5353 }
ysr@777 5354
ysr@777 5355 class CountPopObjInfoClosure: public HeapRegionClosure {
ysr@777 5356 size_t _objs;
ysr@777 5357 size_t _bytes;
ysr@777 5358
ysr@777 5359 class CountObjClosure: public ObjectClosure {
ysr@777 5360 int _n;
ysr@777 5361 public:
ysr@777 5362 CountObjClosure() : _n(0) {}
ysr@777 5363 void do_object(oop obj) { _n++; }
ysr@777 5364 size_t n() { return _n; }
ysr@777 5365 };
ysr@777 5366
ysr@777 5367 public:
ysr@777 5368 CountPopObjInfoClosure() : _objs(0), _bytes(0) {}
ysr@777 5369 bool doHeapRegion(HeapRegion* r) {
ysr@777 5370 _bytes += r->used();
ysr@777 5371 CountObjClosure blk;
ysr@777 5372 r->object_iterate(&blk);
ysr@777 5373 _objs += blk.n();
ysr@777 5374 return false;
ysr@777 5375 }
ysr@777 5376 size_t objs() { return _objs; }
ysr@777 5377 size_t bytes() { return _bytes; }
ysr@777 5378 };
ysr@777 5379
ysr@777 5380
ysr@777 5381 void G1CollectedHeap::print_popularity_summary_info() const {
ysr@777 5382 CountPopObjInfoClosure blk;
ysr@777 5383 for (int i = 0; i <= _cur_pop_hr_index; i++) {
ysr@777 5384 blk.doHeapRegion(_hrs->at(i));
ysr@777 5385 }
ysr@777 5386 gclog_or_tty->print_cr("\nPopular objects: %d objs, %d bytes.",
ysr@777 5387 blk.objs(), blk.bytes());
ysr@777 5388 gclog_or_tty->print_cr(" RC at copy = [avg = %5.2f, max = %5.2f, sd = %5.2f].",
ysr@777 5389 _pop_obj_rc_at_copy.avg(),
ysr@777 5390 _pop_obj_rc_at_copy.maximum(),
ysr@777 5391 _pop_obj_rc_at_copy.sd());
ysr@777 5392 }
ysr@777 5393
ysr@777 5394 void G1CollectedHeap::set_refine_cte_cl_concurrency(bool concurrent) {
ysr@777 5395 _refine_cte_cl->set_concurrent(concurrent);
ysr@777 5396 }
ysr@777 5397
ysr@777 5398 #ifndef PRODUCT
ysr@777 5399
ysr@777 5400 class PrintHeapRegionClosure: public HeapRegionClosure {
ysr@777 5401 public:
ysr@777 5402 bool doHeapRegion(HeapRegion *r) {
ysr@777 5403 gclog_or_tty->print("Region: "PTR_FORMAT":", r);
ysr@777 5404 if (r != NULL) {
ysr@777 5405 if (r->is_on_free_list())
ysr@777 5406 gclog_or_tty->print("Free ");
ysr@777 5407 if (r->is_young())
ysr@777 5408 gclog_or_tty->print("Young ");
ysr@777 5409 if (r->isHumongous())
ysr@777 5410 gclog_or_tty->print("Is Humongous ");
ysr@777 5411 r->print();
ysr@777 5412 }
ysr@777 5413 return false;
ysr@777 5414 }
ysr@777 5415 };
ysr@777 5416
ysr@777 5417 class SortHeapRegionClosure : public HeapRegionClosure {
ysr@777 5418 size_t young_regions,free_regions, unclean_regions;
ysr@777 5419 size_t hum_regions, count;
ysr@777 5420 size_t unaccounted, cur_unclean, cur_alloc;
ysr@777 5421 size_t total_free;
ysr@777 5422 HeapRegion* cur;
ysr@777 5423 public:
ysr@777 5424 SortHeapRegionClosure(HeapRegion *_cur) : cur(_cur), young_regions(0),
ysr@777 5425 free_regions(0), unclean_regions(0),
ysr@777 5426 hum_regions(0),
ysr@777 5427 count(0), unaccounted(0),
ysr@777 5428 cur_alloc(0), total_free(0)
ysr@777 5429 {}
ysr@777 5430 bool doHeapRegion(HeapRegion *r) {
ysr@777 5431 count++;
ysr@777 5432 if (r->is_on_free_list()) free_regions++;
ysr@777 5433 else if (r->is_on_unclean_list()) unclean_regions++;
ysr@777 5434 else if (r->isHumongous()) hum_regions++;
ysr@777 5435 else if (r->is_young()) young_regions++;
ysr@777 5436 else if (r == cur) cur_alloc++;
ysr@777 5437 else unaccounted++;
ysr@777 5438 return false;
ysr@777 5439 }
ysr@777 5440 void print() {
ysr@777 5441 total_free = free_regions + unclean_regions;
ysr@777 5442 gclog_or_tty->print("%d regions\n", count);
ysr@777 5443 gclog_or_tty->print("%d free: free_list = %d unclean = %d\n",
ysr@777 5444 total_free, free_regions, unclean_regions);
ysr@777 5445 gclog_or_tty->print("%d humongous %d young\n",
ysr@777 5446 hum_regions, young_regions);
ysr@777 5447 gclog_or_tty->print("%d cur_alloc\n", cur_alloc);
ysr@777 5448 gclog_or_tty->print("UHOH unaccounted = %d\n", unaccounted);
ysr@777 5449 }
ysr@777 5450 };
ysr@777 5451
ysr@777 5452 void G1CollectedHeap::print_region_counts() {
ysr@777 5453 SortHeapRegionClosure sc(_cur_alloc_region);
ysr@777 5454 PrintHeapRegionClosure cl;
ysr@777 5455 heap_region_iterate(&cl);
ysr@777 5456 heap_region_iterate(&sc);
ysr@777 5457 sc.print();
ysr@777 5458 print_region_accounting_info();
ysr@777 5459 };
ysr@777 5460
ysr@777 5461 bool G1CollectedHeap::regions_accounted_for() {
ysr@777 5462 // TODO: regions accounting for young/survivor/tenured
ysr@777 5463 return true;
ysr@777 5464 }
ysr@777 5465
ysr@777 5466 bool G1CollectedHeap::print_region_accounting_info() {
ysr@777 5467 gclog_or_tty->print_cr("P regions: %d.", G1NumPopularRegions);
ysr@777 5468 gclog_or_tty->print_cr("Free regions: %d (count: %d count list %d) (clean: %d unclean: %d).",
ysr@777 5469 free_regions(),
ysr@777 5470 count_free_regions(), count_free_regions_list(),
ysr@777 5471 _free_region_list_size, _unclean_region_list.sz());
ysr@777 5472 gclog_or_tty->print_cr("cur_alloc: %d.",
ysr@777 5473 (_cur_alloc_region == NULL ? 0 : 1));
ysr@777 5474 gclog_or_tty->print_cr("H regions: %d.", _num_humongous_regions);
ysr@777 5475
ysr@777 5476 // TODO: check regions accounting for young/survivor/tenured
ysr@777 5477 return true;
ysr@777 5478 }
ysr@777 5479
ysr@777 5480 bool G1CollectedHeap::is_in_closed_subset(const void* p) const {
ysr@777 5481 HeapRegion* hr = heap_region_containing(p);
ysr@777 5482 if (hr == NULL) {
ysr@777 5483 return is_in_permanent(p);
ysr@777 5484 } else {
ysr@777 5485 return hr->is_in(p);
ysr@777 5486 }
ysr@777 5487 }
ysr@777 5488 #endif // PRODUCT
ysr@777 5489
ysr@777 5490 void G1CollectedHeap::g1_unimplemented() {
ysr@777 5491 // Unimplemented();
ysr@777 5492 }
ysr@777 5493
ysr@777 5494
ysr@777 5495 // Local Variables: ***
ysr@777 5496 // c-indentation-style: gnu ***
ysr@777 5497 // End: ***

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