Mercurial > hg > truffle
annotate src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp @ 488:569b3b226089
Merge
| author | trims |
|---|---|
| date | Sat, 20 Dec 2008 09:57:03 -0800 |
| parents | 7d7a7c599c17 ad8c8ca4ab0f |
| children | 818efdefcc99 |
| rev | line source |
|---|---|
| 342 | 1 /* |
| 470 | 2 * Copyright 2001-2008 Sun Microsystems, Inc. All Rights Reserved. |
| 342 | 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 * | |
| 5 * This code is free software; you can redistribute it and/or modify it | |
| 6 * under the terms of the GNU General Public License version 2 only, as | |
| 7 * published by the Free Software Foundation. | |
| 8 * | |
| 9 * This code is distributed in the hope that it will be useful, but WITHOUT | |
| 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 12 * version 2 for more details (a copy is included in the LICENSE file that | |
| 13 * accompanied this code). | |
| 14 * | |
| 15 * You should have received a copy of the GNU General Public License version | |
| 16 * 2 along with this work; if not, write to the Free Software Foundation, | |
| 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
| 18 * | |
| 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
| 20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
| 21 * have any questions. | |
| 22 * | |
| 23 */ | |
| 24 | |
| 25 #include "incls/_precompiled.incl" | |
| 26 #include "incls/_g1CollectedHeap.cpp.incl" | |
| 27 | |
| 28 // turn it on so that the contents of the young list (scan-only / | |
| 29 // to-be-collected) are printed at "strategic" points before / during | |
| 30 // / after the collection --- this is useful for debugging | |
| 31 #define SCAN_ONLY_VERBOSE 0 | |
| 32 // CURRENT STATUS | |
| 33 // This file is under construction. Search for "FIXME". | |
| 34 | |
| 35 // INVARIANTS/NOTES | |
| 36 // | |
| 37 // All allocation activity covered by the G1CollectedHeap interface is | |
| 38 // serialized by acquiring the HeapLock. This happens in | |
| 39 // mem_allocate_work, which all such allocation functions call. | |
| 40 // (Note that this does not apply to TLAB allocation, which is not part | |
| 41 // of this interface: it is done by clients of this interface.) | |
| 42 | |
| 43 // Local to this file. | |
| 44 | |
| 45 // Finds the first HeapRegion. | |
| 46 // No longer used, but might be handy someday. | |
| 47 | |
| 48 class FindFirstRegionClosure: public HeapRegionClosure { | |
| 49 HeapRegion* _a_region; | |
| 50 public: | |
| 51 FindFirstRegionClosure() : _a_region(NULL) {} | |
| 52 bool doHeapRegion(HeapRegion* r) { | |
| 53 _a_region = r; | |
| 54 return true; | |
| 55 } | |
| 56 HeapRegion* result() { return _a_region; } | |
| 57 }; | |
| 58 | |
| 59 | |
| 60 class RefineCardTableEntryClosure: public CardTableEntryClosure { | |
| 61 SuspendibleThreadSet* _sts; | |
| 62 G1RemSet* _g1rs; | |
| 63 ConcurrentG1Refine* _cg1r; | |
| 64 bool _concurrent; | |
| 65 public: | |
| 66 RefineCardTableEntryClosure(SuspendibleThreadSet* sts, | |
| 67 G1RemSet* g1rs, | |
| 68 ConcurrentG1Refine* cg1r) : | |
| 69 _sts(sts), _g1rs(g1rs), _cg1r(cg1r), _concurrent(true) | |
| 70 {} | |
| 71 bool do_card_ptr(jbyte* card_ptr, int worker_i) { | |
| 72 _g1rs->concurrentRefineOneCard(card_ptr, worker_i); | |
| 73 if (_concurrent && _sts->should_yield()) { | |
| 74 // Caller will actually yield. | |
| 75 return false; | |
| 76 } | |
| 77 // Otherwise, we finished successfully; return true. | |
| 78 return true; | |
| 79 } | |
| 80 void set_concurrent(bool b) { _concurrent = b; } | |
| 81 }; | |
| 82 | |
| 83 | |
| 84 class ClearLoggedCardTableEntryClosure: public CardTableEntryClosure { | |
| 85 int _calls; | |
| 86 G1CollectedHeap* _g1h; | |
| 87 CardTableModRefBS* _ctbs; | |
| 88 int _histo[256]; | |
| 89 public: | |
| 90 ClearLoggedCardTableEntryClosure() : | |
| 91 _calls(0) | |
| 92 { | |
| 93 _g1h = G1CollectedHeap::heap(); | |
| 94 _ctbs = (CardTableModRefBS*)_g1h->barrier_set(); | |
| 95 for (int i = 0; i < 256; i++) _histo[i] = 0; | |
| 96 } | |
| 97 bool do_card_ptr(jbyte* card_ptr, int worker_i) { | |
| 98 if (_g1h->is_in_reserved(_ctbs->addr_for(card_ptr))) { | |
| 99 _calls++; | |
| 100 unsigned char* ujb = (unsigned char*)card_ptr; | |
| 101 int ind = (int)(*ujb); | |
| 102 _histo[ind]++; | |
| 103 *card_ptr = -1; | |
| 104 } | |
| 105 return true; | |
| 106 } | |
| 107 int calls() { return _calls; } | |
| 108 void print_histo() { | |
| 109 gclog_or_tty->print_cr("Card table value histogram:"); | |
| 110 for (int i = 0; i < 256; i++) { | |
| 111 if (_histo[i] != 0) { | |
| 112 gclog_or_tty->print_cr(" %d: %d", i, _histo[i]); | |
| 113 } | |
| 114 } | |
| 115 } | |
| 116 }; | |
| 117 | |
| 118 class RedirtyLoggedCardTableEntryClosure: public CardTableEntryClosure { | |
| 119 int _calls; | |
| 120 G1CollectedHeap* _g1h; | |
| 121 CardTableModRefBS* _ctbs; | |
| 122 public: | |
| 123 RedirtyLoggedCardTableEntryClosure() : | |
| 124 _calls(0) | |
| 125 { | |
| 126 _g1h = G1CollectedHeap::heap(); | |
| 127 _ctbs = (CardTableModRefBS*)_g1h->barrier_set(); | |
| 128 } | |
| 129 bool do_card_ptr(jbyte* card_ptr, int worker_i) { | |
| 130 if (_g1h->is_in_reserved(_ctbs->addr_for(card_ptr))) { | |
| 131 _calls++; | |
| 132 *card_ptr = 0; | |
| 133 } | |
| 134 return true; | |
| 135 } | |
| 136 int calls() { return _calls; } | |
| 137 }; | |
| 138 | |
| 139 YoungList::YoungList(G1CollectedHeap* g1h) | |
| 140 : _g1h(g1h), _head(NULL), | |
| 141 _scan_only_head(NULL), _scan_only_tail(NULL), _curr_scan_only(NULL), | |
| 142 _length(0), _scan_only_length(0), | |
| 143 _last_sampled_rs_lengths(0), | |
| 144 _survivor_head(NULL), _survivors_tail(NULL), _survivor_length(0) | |
| 145 { | |
| 146 guarantee( check_list_empty(false), "just making sure..." ); | |
| 147 } | |
| 148 | |
| 149 void YoungList::push_region(HeapRegion *hr) { | |
| 150 assert(!hr->is_young(), "should not already be young"); | |
| 151 assert(hr->get_next_young_region() == NULL, "cause it should!"); | |
| 152 | |
| 153 hr->set_next_young_region(_head); | |
| 154 _head = hr; | |
| 155 | |
| 156 hr->set_young(); | |
| 157 double yg_surv_rate = _g1h->g1_policy()->predict_yg_surv_rate((int)_length); | |
| 158 ++_length; | |
| 159 } | |
| 160 | |
| 161 void YoungList::add_survivor_region(HeapRegion* hr) { | |
| 162 assert(!hr->is_survivor(), "should not already be for survived"); | |
| 163 assert(hr->get_next_young_region() == NULL, "cause it should!"); | |
| 164 | |
| 165 hr->set_next_young_region(_survivor_head); | |
| 166 if (_survivor_head == NULL) { | |
| 167 _survivors_tail = hr; | |
| 168 } | |
| 169 _survivor_head = hr; | |
| 170 | |
| 171 hr->set_survivor(); | |
| 172 ++_survivor_length; | |
| 173 } | |
| 174 | |
| 175 HeapRegion* YoungList::pop_region() { | |
| 176 while (_head != NULL) { | |
| 177 assert( length() > 0, "list should not be empty" ); | |
| 178 HeapRegion* ret = _head; | |
| 179 _head = ret->get_next_young_region(); | |
| 180 ret->set_next_young_region(NULL); | |
| 181 --_length; | |
| 182 assert(ret->is_young(), "region should be very young"); | |
| 183 | |
| 184 // Replace 'Survivor' region type with 'Young'. So the region will | |
| 185 // be treated as a young region and will not be 'confused' with | |
| 186 // newly created survivor regions. | |
| 187 if (ret->is_survivor()) { | |
| 188 ret->set_young(); | |
| 189 } | |
| 190 | |
| 191 if (!ret->is_scan_only()) { | |
| 192 return ret; | |
| 193 } | |
| 194 | |
| 195 // scan-only, we'll add it to the scan-only list | |
| 196 if (_scan_only_tail == NULL) { | |
| 197 guarantee( _scan_only_head == NULL, "invariant" ); | |
| 198 | |
| 199 _scan_only_head = ret; | |
| 200 _curr_scan_only = ret; | |
| 201 } else { | |
| 202 guarantee( _scan_only_head != NULL, "invariant" ); | |
| 203 _scan_only_tail->set_next_young_region(ret); | |
| 204 } | |
| 205 guarantee( ret->get_next_young_region() == NULL, "invariant" ); | |
| 206 _scan_only_tail = ret; | |
| 207 | |
| 208 // no need to be tagged as scan-only any more | |
| 209 ret->set_young(); | |
| 210 | |
| 211 ++_scan_only_length; | |
| 212 } | |
| 213 assert( length() == 0, "list should be empty" ); | |
| 214 return NULL; | |
| 215 } | |
| 216 | |
| 217 void YoungList::empty_list(HeapRegion* list) { | |
| 218 while (list != NULL) { | |
| 219 HeapRegion* next = list->get_next_young_region(); | |
| 220 list->set_next_young_region(NULL); | |
| 221 list->uninstall_surv_rate_group(); | |
| 222 list->set_not_young(); | |
| 223 list = next; | |
| 224 } | |
| 225 } | |
| 226 | |
| 227 void YoungList::empty_list() { | |
| 228 assert(check_list_well_formed(), "young list should be well formed"); | |
| 229 | |
| 230 empty_list(_head); | |
| 231 _head = NULL; | |
| 232 _length = 0; | |
| 233 | |
| 234 empty_list(_scan_only_head); | |
| 235 _scan_only_head = NULL; | |
| 236 _scan_only_tail = NULL; | |
| 237 _scan_only_length = 0; | |
| 238 _curr_scan_only = NULL; | |
| 239 | |
| 240 empty_list(_survivor_head); | |
| 241 _survivor_head = NULL; | |
| 242 _survivors_tail = NULL; | |
| 243 _survivor_length = 0; | |
| 244 | |
| 245 _last_sampled_rs_lengths = 0; | |
| 246 | |
| 247 assert(check_list_empty(false), "just making sure..."); | |
| 248 } | |
| 249 | |
| 250 bool YoungList::check_list_well_formed() { | |
| 251 bool ret = true; | |
| 252 | |
| 253 size_t length = 0; | |
| 254 HeapRegion* curr = _head; | |
| 255 HeapRegion* last = NULL; | |
| 256 while (curr != NULL) { | |
| 257 if (!curr->is_young() || curr->is_scan_only()) { | |
| 258 gclog_or_tty->print_cr("### YOUNG REGION "PTR_FORMAT"-"PTR_FORMAT" " | |
| 259 "incorrectly tagged (%d, %d)", | |
| 260 curr->bottom(), curr->end(), | |
| 261 curr->is_young(), curr->is_scan_only()); | |
| 262 ret = false; | |
| 263 } | |
| 264 ++length; | |
| 265 last = curr; | |
| 266 curr = curr->get_next_young_region(); | |
| 267 } | |
| 268 ret = ret && (length == _length); | |
| 269 | |
| 270 if (!ret) { | |
| 271 gclog_or_tty->print_cr("### YOUNG LIST seems not well formed!"); | |
| 272 gclog_or_tty->print_cr("### list has %d entries, _length is %d", | |
| 273 length, _length); | |
| 274 } | |
| 275 | |
| 276 bool scan_only_ret = true; | |
| 277 length = 0; | |
| 278 curr = _scan_only_head; | |
| 279 last = NULL; | |
| 280 while (curr != NULL) { | |
| 281 if (!curr->is_young() || curr->is_scan_only()) { | |
| 282 gclog_or_tty->print_cr("### SCAN-ONLY REGION "PTR_FORMAT"-"PTR_FORMAT" " | |
| 283 "incorrectly tagged (%d, %d)", | |
| 284 curr->bottom(), curr->end(), | |
| 285 curr->is_young(), curr->is_scan_only()); | |
| 286 scan_only_ret = false; | |
| 287 } | |
| 288 ++length; | |
| 289 last = curr; | |
| 290 curr = curr->get_next_young_region(); | |
| 291 } | |
| 292 scan_only_ret = scan_only_ret && (length == _scan_only_length); | |
| 293 | |
| 294 if ( (last != _scan_only_tail) || | |
| 295 (_scan_only_head == NULL && _scan_only_tail != NULL) || | |
| 296 (_scan_only_head != NULL && _scan_only_tail == NULL) ) { | |
| 297 gclog_or_tty->print_cr("## _scan_only_tail is set incorrectly"); | |
| 298 scan_only_ret = false; | |
| 299 } | |
| 300 | |
| 301 if (_curr_scan_only != NULL && _curr_scan_only != _scan_only_head) { | |
| 302 gclog_or_tty->print_cr("### _curr_scan_only is set incorrectly"); | |
| 303 scan_only_ret = false; | |
| 304 } | |
| 305 | |
| 306 if (!scan_only_ret) { | |
| 307 gclog_or_tty->print_cr("### SCAN-ONLY LIST seems not well formed!"); | |
| 308 gclog_or_tty->print_cr("### list has %d entries, _scan_only_length is %d", | |
| 309 length, _scan_only_length); | |
| 310 } | |
| 311 | |
| 312 return ret && scan_only_ret; | |
| 313 } | |
| 314 | |
| 315 bool YoungList::check_list_empty(bool ignore_scan_only_list, | |
| 316 bool check_sample) { | |
| 317 bool ret = true; | |
| 318 | |
| 319 if (_length != 0) { | |
| 320 gclog_or_tty->print_cr("### YOUNG LIST should have 0 length, not %d", | |
| 321 _length); | |
| 322 ret = false; | |
| 323 } | |
| 324 if (check_sample && _last_sampled_rs_lengths != 0) { | |
| 325 gclog_or_tty->print_cr("### YOUNG LIST has non-zero last sampled RS lengths"); | |
| 326 ret = false; | |
| 327 } | |
| 328 if (_head != NULL) { | |
| 329 gclog_or_tty->print_cr("### YOUNG LIST does not have a NULL head"); | |
| 330 ret = false; | |
| 331 } | |
| 332 if (!ret) { | |
| 333 gclog_or_tty->print_cr("### YOUNG LIST does not seem empty"); | |
| 334 } | |
| 335 | |
| 336 if (ignore_scan_only_list) | |
| 337 return ret; | |
| 338 | |
| 339 bool scan_only_ret = true; | |
| 340 if (_scan_only_length != 0) { | |
| 341 gclog_or_tty->print_cr("### SCAN-ONLY LIST should have 0 length, not %d", | |
| 342 _scan_only_length); | |
| 343 scan_only_ret = false; | |
| 344 } | |
| 345 if (_scan_only_head != NULL) { | |
| 346 gclog_or_tty->print_cr("### SCAN-ONLY LIST does not have a NULL head"); | |
| 347 scan_only_ret = false; | |
| 348 } | |
| 349 if (_scan_only_tail != NULL) { | |
| 350 gclog_or_tty->print_cr("### SCAN-ONLY LIST does not have a NULL tail"); | |
| 351 scan_only_ret = false; | |
| 352 } | |
| 353 if (!scan_only_ret) { | |
| 354 gclog_or_tty->print_cr("### SCAN-ONLY LIST does not seem empty"); | |
| 355 } | |
| 356 | |
| 357 return ret && scan_only_ret; | |
| 358 } | |
| 359 | |
| 360 void | |
| 361 YoungList::rs_length_sampling_init() { | |
| 362 _sampled_rs_lengths = 0; | |
| 363 _curr = _head; | |
| 364 } | |
| 365 | |
| 366 bool | |
| 367 YoungList::rs_length_sampling_more() { | |
| 368 return _curr != NULL; | |
| 369 } | |
| 370 | |
| 371 void | |
| 372 YoungList::rs_length_sampling_next() { | |
| 373 assert( _curr != NULL, "invariant" ); | |
| 374 _sampled_rs_lengths += _curr->rem_set()->occupied(); | |
| 375 _curr = _curr->get_next_young_region(); | |
| 376 if (_curr == NULL) { | |
| 377 _last_sampled_rs_lengths = _sampled_rs_lengths; | |
| 378 // gclog_or_tty->print_cr("last sampled RS lengths = %d", _last_sampled_rs_lengths); | |
| 379 } | |
| 380 } | |
| 381 | |
| 382 void | |
| 383 YoungList::reset_auxilary_lists() { | |
| 384 // We could have just "moved" the scan-only list to the young list. | |
| 385 // However, the scan-only list is ordered according to the region | |
| 386 // age in descending order, so, by moving one entry at a time, we | |
| 387 // ensure that it is recreated in ascending order. | |
| 388 | |
| 389 guarantee( is_empty(), "young list should be empty" ); | |
| 390 assert(check_list_well_formed(), "young list should be well formed"); | |
| 391 | |
| 392 // Add survivor regions to SurvRateGroup. | |
| 393 _g1h->g1_policy()->note_start_adding_survivor_regions(); | |
| 394 for (HeapRegion* curr = _survivor_head; | |
| 395 curr != NULL; | |
| 396 curr = curr->get_next_young_region()) { | |
| 397 _g1h->g1_policy()->set_region_survivors(curr); | |
| 398 } | |
| 399 _g1h->g1_policy()->note_stop_adding_survivor_regions(); | |
| 400 | |
| 401 if (_survivor_head != NULL) { | |
| 402 _head = _survivor_head; | |
| 403 _length = _survivor_length + _scan_only_length; | |
| 404 _survivors_tail->set_next_young_region(_scan_only_head); | |
| 405 } else { | |
| 406 _head = _scan_only_head; | |
| 407 _length = _scan_only_length; | |
| 408 } | |
| 409 | |
| 410 for (HeapRegion* curr = _scan_only_head; | |
| 411 curr != NULL; | |
| 412 curr = curr->get_next_young_region()) { | |
| 413 curr->recalculate_age_in_surv_rate_group(); | |
| 414 } | |
| 415 _scan_only_head = NULL; | |
| 416 _scan_only_tail = NULL; | |
| 417 _scan_only_length = 0; | |
| 418 _curr_scan_only = NULL; | |
| 419 | |
| 420 _survivor_head = NULL; | |
| 421 _survivors_tail = NULL; | |
| 422 _survivor_length = 0; | |
| 423 _g1h->g1_policy()->finished_recalculating_age_indexes(); | |
| 424 | |
| 425 assert(check_list_well_formed(), "young list should be well formed"); | |
| 426 } | |
| 427 | |
| 428 void YoungList::print() { | |
| 429 HeapRegion* lists[] = {_head, _scan_only_head, _survivor_head}; | |
| 430 const char* names[] = {"YOUNG", "SCAN-ONLY", "SURVIVOR"}; | |
| 431 | |
| 432 for (unsigned int list = 0; list < ARRAY_SIZE(lists); ++list) { | |
| 433 gclog_or_tty->print_cr("%s LIST CONTENTS", names[list]); | |
| 434 HeapRegion *curr = lists[list]; | |
| 435 if (curr == NULL) | |
| 436 gclog_or_tty->print_cr(" empty"); | |
| 437 while (curr != NULL) { | |
| 438 gclog_or_tty->print_cr(" [%08x-%08x], t: %08x, P: %08x, N: %08x, C: %08x, " | |
| 439 "age: %4d, y: %d, s-o: %d, surv: %d", | |
| 440 curr->bottom(), curr->end(), | |
| 441 curr->top(), | |
| 442 curr->prev_top_at_mark_start(), | |
| 443 curr->next_top_at_mark_start(), | |
| 444 curr->top_at_conc_mark_count(), | |
| 445 curr->age_in_surv_rate_group_cond(), | |
| 446 curr->is_young(), | |
| 447 curr->is_scan_only(), | |
| 448 curr->is_survivor()); | |
| 449 curr = curr->get_next_young_region(); | |
| 450 } | |
| 451 } | |
| 452 | |
| 453 gclog_or_tty->print_cr(""); | |
| 454 } | |
| 455 | |
| 456 void G1CollectedHeap::stop_conc_gc_threads() { | |
| 457 _cg1r->cg1rThread()->stop(); | |
| 458 _czft->stop(); | |
| 459 _cmThread->stop(); | |
| 460 } | |
| 461 | |
| 462 | |
| 463 void G1CollectedHeap::check_ct_logs_at_safepoint() { | |
| 464 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 465 CardTableModRefBS* ct_bs = (CardTableModRefBS*)barrier_set(); | |
| 466 | |
| 467 // Count the dirty cards at the start. | |
| 468 CountNonCleanMemRegionClosure count1(this); | |
| 469 ct_bs->mod_card_iterate(&count1); | |
| 470 int orig_count = count1.n(); | |
| 471 | |
| 472 // First clear the logged cards. | |
| 473 ClearLoggedCardTableEntryClosure clear; | |
| 474 dcqs.set_closure(&clear); | |
| 475 dcqs.apply_closure_to_all_completed_buffers(); | |
| 476 dcqs.iterate_closure_all_threads(false); | |
| 477 clear.print_histo(); | |
| 478 | |
| 479 // Now ensure that there's no dirty cards. | |
| 480 CountNonCleanMemRegionClosure count2(this); | |
| 481 ct_bs->mod_card_iterate(&count2); | |
| 482 if (count2.n() != 0) { | |
| 483 gclog_or_tty->print_cr("Card table has %d entries; %d originally", | |
| 484 count2.n(), orig_count); | |
| 485 } | |
| 486 guarantee(count2.n() == 0, "Card table should be clean."); | |
| 487 | |
| 488 RedirtyLoggedCardTableEntryClosure redirty; | |
| 489 JavaThread::dirty_card_queue_set().set_closure(&redirty); | |
| 490 dcqs.apply_closure_to_all_completed_buffers(); | |
| 491 dcqs.iterate_closure_all_threads(false); | |
| 492 gclog_or_tty->print_cr("Log entries = %d, dirty cards = %d.", | |
| 493 clear.calls(), orig_count); | |
| 494 guarantee(redirty.calls() == clear.calls(), | |
| 495 "Or else mechanism is broken."); | |
| 496 | |
| 497 CountNonCleanMemRegionClosure count3(this); | |
| 498 ct_bs->mod_card_iterate(&count3); | |
| 499 if (count3.n() != orig_count) { | |
| 500 gclog_or_tty->print_cr("Should have restored them all: orig = %d, final = %d.", | |
| 501 orig_count, count3.n()); | |
| 502 guarantee(count3.n() >= orig_count, "Should have restored them all."); | |
| 503 } | |
| 504 | |
| 505 JavaThread::dirty_card_queue_set().set_closure(_refine_cte_cl); | |
| 506 } | |
| 507 | |
| 508 // Private class members. | |
| 509 | |
| 510 G1CollectedHeap* G1CollectedHeap::_g1h; | |
| 511 | |
| 512 // Private methods. | |
| 513 | |
| 514 // Finds a HeapRegion that can be used to allocate a given size of block. | |
| 515 | |
| 516 | |
| 517 HeapRegion* G1CollectedHeap::newAllocRegion_work(size_t word_size, | |
| 518 bool do_expand, | |
| 519 bool zero_filled) { | |
| 520 ConcurrentZFThread::note_region_alloc(); | |
| 521 HeapRegion* res = alloc_free_region_from_lists(zero_filled); | |
| 522 if (res == NULL && do_expand) { | |
| 523 expand(word_size * HeapWordSize); | |
| 524 res = alloc_free_region_from_lists(zero_filled); | |
| 525 assert(res == NULL || | |
| 526 (!res->isHumongous() && | |
| 527 (!zero_filled || | |
| 528 res->zero_fill_state() == HeapRegion::Allocated)), | |
| 529 "Alloc Regions must be zero filled (and non-H)"); | |
| 530 } | |
| 531 if (res != NULL && res->is_empty()) _free_regions--; | |
| 532 assert(res == NULL || | |
| 533 (!res->isHumongous() && | |
| 534 (!zero_filled || | |
| 535 res->zero_fill_state() == HeapRegion::Allocated)), | |
| 536 "Non-young alloc Regions must be zero filled (and non-H)"); | |
| 537 | |
| 538 if (G1TraceRegions) { | |
| 539 if (res != NULL) { | |
| 540 gclog_or_tty->print_cr("new alloc region %d:["PTR_FORMAT", "PTR_FORMAT"], " | |
| 541 "top "PTR_FORMAT, | |
| 542 res->hrs_index(), res->bottom(), res->end(), res->top()); | |
| 543 } | |
| 544 } | |
| 545 | |
| 546 return res; | |
| 547 } | |
| 548 | |
| 549 HeapRegion* G1CollectedHeap::newAllocRegionWithExpansion(int purpose, | |
| 550 size_t word_size, | |
| 551 bool zero_filled) { | |
| 552 HeapRegion* alloc_region = NULL; | |
| 553 if (_gc_alloc_region_counts[purpose] < g1_policy()->max_regions(purpose)) { | |
| 554 alloc_region = newAllocRegion_work(word_size, true, zero_filled); | |
| 555 if (purpose == GCAllocForSurvived && alloc_region != NULL) { | |
| 556 _young_list->add_survivor_region(alloc_region); | |
| 557 } | |
| 558 ++_gc_alloc_region_counts[purpose]; | |
| 559 } else { | |
| 560 g1_policy()->note_alloc_region_limit_reached(purpose); | |
| 561 } | |
| 562 return alloc_region; | |
| 563 } | |
| 564 | |
| 565 // If could fit into free regions w/o expansion, try. | |
| 566 // Otherwise, if can expand, do so. | |
| 567 // Otherwise, if using ex regions might help, try with ex given back. | |
| 568 HeapWord* G1CollectedHeap::humongousObjAllocate(size_t word_size) { | |
| 569 assert(regions_accounted_for(), "Region leakage!"); | |
| 570 | |
| 571 // We can't allocate H regions while cleanupComplete is running, since | |
| 572 // some of the regions we find to be empty might not yet be added to the | |
| 573 // unclean list. (If we're already at a safepoint, this call is | |
| 574 // unnecessary, not to mention wrong.) | |
| 575 if (!SafepointSynchronize::is_at_safepoint()) | |
| 576 wait_for_cleanup_complete(); | |
| 577 | |
| 578 size_t num_regions = | |
| 579 round_to(word_size, HeapRegion::GrainWords) / HeapRegion::GrainWords; | |
| 580 | |
| 581 // Special case if < one region??? | |
| 582 | |
| 583 // Remember the ft size. | |
| 584 size_t x_size = expansion_regions(); | |
| 585 | |
| 586 HeapWord* res = NULL; | |
| 587 bool eliminated_allocated_from_lists = false; | |
| 588 | |
| 589 // Can the allocation potentially fit in the free regions? | |
| 590 if (free_regions() >= num_regions) { | |
| 591 res = _hrs->obj_allocate(word_size); | |
| 592 } | |
| 593 if (res == NULL) { | |
| 594 // Try expansion. | |
| 595 size_t fs = _hrs->free_suffix(); | |
| 596 if (fs + x_size >= num_regions) { | |
| 597 expand((num_regions - fs) * HeapRegion::GrainBytes); | |
| 598 res = _hrs->obj_allocate(word_size); | |
| 599 assert(res != NULL, "This should have worked."); | |
| 600 } else { | |
| 601 // Expansion won't help. Are there enough free regions if we get rid | |
| 602 // of reservations? | |
| 603 size_t avail = free_regions(); | |
| 604 if (avail >= num_regions) { | |
| 605 res = _hrs->obj_allocate(word_size); | |
| 606 if (res != NULL) { | |
| 607 remove_allocated_regions_from_lists(); | |
| 608 eliminated_allocated_from_lists = true; | |
| 609 } | |
| 610 } | |
| 611 } | |
| 612 } | |
| 613 if (res != NULL) { | |
| 614 // Increment by the number of regions allocated. | |
| 615 // FIXME: Assumes regions all of size GrainBytes. | |
| 616 #ifndef PRODUCT | |
| 617 mr_bs()->verify_clean_region(MemRegion(res, res + num_regions * | |
| 618 HeapRegion::GrainWords)); | |
| 619 #endif | |
| 620 if (!eliminated_allocated_from_lists) | |
| 621 remove_allocated_regions_from_lists(); | |
| 622 _summary_bytes_used += word_size * HeapWordSize; | |
| 623 _free_regions -= num_regions; | |
| 624 _num_humongous_regions += (int) num_regions; | |
| 625 } | |
| 626 assert(regions_accounted_for(), "Region Leakage"); | |
| 627 return res; | |
| 628 } | |
| 629 | |
| 630 HeapWord* | |
| 631 G1CollectedHeap::attempt_allocation_slow(size_t word_size, | |
| 632 bool permit_collection_pause) { | |
| 633 HeapWord* res = NULL; | |
| 634 HeapRegion* allocated_young_region = NULL; | |
| 635 | |
| 636 assert( SafepointSynchronize::is_at_safepoint() || | |
| 637 Heap_lock->owned_by_self(), "pre condition of the call" ); | |
| 638 | |
| 639 if (isHumongous(word_size)) { | |
| 640 // Allocation of a humongous object can, in a sense, complete a | |
| 641 // partial region, if the previous alloc was also humongous, and | |
| 642 // caused the test below to succeed. | |
| 643 if (permit_collection_pause) | |
| 644 do_collection_pause_if_appropriate(word_size); | |
| 645 res = humongousObjAllocate(word_size); | |
| 646 assert(_cur_alloc_region == NULL | |
| 647 || !_cur_alloc_region->isHumongous(), | |
| 648 "Prevent a regression of this bug."); | |
| 649 | |
| 650 } else { | |
|
354
c0f8f7790199
6652160: G1: assert(cur_used_bytes == _g1->recalculate_used(),"It should!") at g1CollectorPolicy.cpp:1425
iveresov
parents:
353
diff
changeset
|
651 // We may have concurrent cleanup working at the time. Wait for it |
|
c0f8f7790199
6652160: G1: assert(cur_used_bytes == _g1->recalculate_used(),"It should!") at g1CollectorPolicy.cpp:1425
iveresov
parents:
353
diff
changeset
|
652 // to complete. In the future we would probably want to make the |
|
c0f8f7790199
6652160: G1: assert(cur_used_bytes == _g1->recalculate_used(),"It should!") at g1CollectorPolicy.cpp:1425
iveresov
parents:
353
diff
changeset
|
653 // concurrent cleanup truly concurrent by decoupling it from the |
|
c0f8f7790199
6652160: G1: assert(cur_used_bytes == _g1->recalculate_used(),"It should!") at g1CollectorPolicy.cpp:1425
iveresov
parents:
353
diff
changeset
|
654 // allocation. |
|
c0f8f7790199
6652160: G1: assert(cur_used_bytes == _g1->recalculate_used(),"It should!") at g1CollectorPolicy.cpp:1425
iveresov
parents:
353
diff
changeset
|
655 if (!SafepointSynchronize::is_at_safepoint()) |
|
c0f8f7790199
6652160: G1: assert(cur_used_bytes == _g1->recalculate_used(),"It should!") at g1CollectorPolicy.cpp:1425
iveresov
parents:
353
diff
changeset
|
656 wait_for_cleanup_complete(); |
| 342 | 657 // If we do a collection pause, this will be reset to a non-NULL |
| 658 // value. If we don't, nulling here ensures that we allocate a new | |
| 659 // region below. | |
| 660 if (_cur_alloc_region != NULL) { | |
| 661 // We're finished with the _cur_alloc_region. | |
| 662 _summary_bytes_used += _cur_alloc_region->used(); | |
| 663 _cur_alloc_region = NULL; | |
| 664 } | |
| 665 assert(_cur_alloc_region == NULL, "Invariant."); | |
| 666 // Completion of a heap region is perhaps a good point at which to do | |
| 667 // a collection pause. | |
| 668 if (permit_collection_pause) | |
| 669 do_collection_pause_if_appropriate(word_size); | |
| 670 // Make sure we have an allocation region available. | |
| 671 if (_cur_alloc_region == NULL) { | |
| 672 if (!SafepointSynchronize::is_at_safepoint()) | |
| 673 wait_for_cleanup_complete(); | |
| 674 bool next_is_young = should_set_young_locked(); | |
| 675 // If the next region is not young, make sure it's zero-filled. | |
| 676 _cur_alloc_region = newAllocRegion(word_size, !next_is_young); | |
| 677 if (_cur_alloc_region != NULL) { | |
| 678 _summary_bytes_used -= _cur_alloc_region->used(); | |
| 679 if (next_is_young) { | |
| 680 set_region_short_lived_locked(_cur_alloc_region); | |
| 681 allocated_young_region = _cur_alloc_region; | |
| 682 } | |
| 683 } | |
| 684 } | |
| 685 assert(_cur_alloc_region == NULL || !_cur_alloc_region->isHumongous(), | |
| 686 "Prevent a regression of this bug."); | |
| 687 | |
| 688 // Now retry the allocation. | |
| 689 if (_cur_alloc_region != NULL) { | |
| 690 res = _cur_alloc_region->allocate(word_size); | |
| 691 } | |
| 692 } | |
| 693 | |
| 694 // NOTE: fails frequently in PRT | |
| 695 assert(regions_accounted_for(), "Region leakage!"); | |
| 696 | |
| 697 if (res != NULL) { | |
| 698 if (!SafepointSynchronize::is_at_safepoint()) { | |
| 699 assert( permit_collection_pause, "invariant" ); | |
| 700 assert( Heap_lock->owned_by_self(), "invariant" ); | |
| 701 Heap_lock->unlock(); | |
| 702 } | |
| 703 | |
| 704 if (allocated_young_region != NULL) { | |
| 705 HeapRegion* hr = allocated_young_region; | |
| 706 HeapWord* bottom = hr->bottom(); | |
| 707 HeapWord* end = hr->end(); | |
| 708 MemRegion mr(bottom, end); | |
| 709 ((CardTableModRefBS*)_g1h->barrier_set())->dirty(mr); | |
| 710 } | |
| 711 } | |
| 712 | |
| 713 assert( SafepointSynchronize::is_at_safepoint() || | |
| 714 (res == NULL && Heap_lock->owned_by_self()) || | |
| 715 (res != NULL && !Heap_lock->owned_by_self()), | |
| 716 "post condition of the call" ); | |
| 717 | |
| 718 return res; | |
| 719 } | |
| 720 | |
| 721 HeapWord* | |
| 722 G1CollectedHeap::mem_allocate(size_t word_size, | |
| 723 bool is_noref, | |
| 724 bool is_tlab, | |
| 725 bool* gc_overhead_limit_was_exceeded) { | |
| 726 debug_only(check_for_valid_allocation_state()); | |
| 727 assert(no_gc_in_progress(), "Allocation during gc not allowed"); | |
| 728 HeapWord* result = NULL; | |
| 729 | |
| 730 // Loop until the allocation is satisified, | |
| 731 // or unsatisfied after GC. | |
| 732 for (int try_count = 1; /* return or throw */; try_count += 1) { | |
| 733 int gc_count_before; | |
| 734 { | |
| 735 Heap_lock->lock(); | |
| 736 result = attempt_allocation(word_size); | |
| 737 if (result != NULL) { | |
| 738 // attempt_allocation should have unlocked the heap lock | |
| 739 assert(is_in(result), "result not in heap"); | |
| 740 return result; | |
| 741 } | |
| 742 // Read the gc count while the heap lock is held. | |
| 743 gc_count_before = SharedHeap::heap()->total_collections(); | |
| 744 Heap_lock->unlock(); | |
| 745 } | |
| 746 | |
| 747 // Create the garbage collection operation... | |
| 748 VM_G1CollectForAllocation op(word_size, | |
| 749 gc_count_before); | |
| 750 | |
| 751 // ...and get the VM thread to execute it. | |
| 752 VMThread::execute(&op); | |
| 753 if (op.prologue_succeeded()) { | |
| 754 result = op.result(); | |
| 755 assert(result == NULL || is_in(result), "result not in heap"); | |
| 756 return result; | |
| 757 } | |
| 758 | |
| 759 // Give a warning if we seem to be looping forever. | |
| 760 if ((QueuedAllocationWarningCount > 0) && | |
| 761 (try_count % QueuedAllocationWarningCount == 0)) { | |
| 762 warning("G1CollectedHeap::mem_allocate_work retries %d times", | |
| 763 try_count); | |
| 764 } | |
| 765 } | |
| 766 } | |
| 767 | |
| 768 void G1CollectedHeap::abandon_cur_alloc_region() { | |
| 769 if (_cur_alloc_region != NULL) { | |
| 770 // We're finished with the _cur_alloc_region. | |
| 771 if (_cur_alloc_region->is_empty()) { | |
| 772 _free_regions++; | |
| 773 free_region(_cur_alloc_region); | |
| 774 } else { | |
| 775 _summary_bytes_used += _cur_alloc_region->used(); | |
| 776 } | |
| 777 _cur_alloc_region = NULL; | |
| 778 } | |
| 779 } | |
| 780 | |
| 781 class PostMCRemSetClearClosure: public HeapRegionClosure { | |
| 782 ModRefBarrierSet* _mr_bs; | |
| 783 public: | |
| 784 PostMCRemSetClearClosure(ModRefBarrierSet* mr_bs) : _mr_bs(mr_bs) {} | |
| 785 bool doHeapRegion(HeapRegion* r) { | |
| 786 r->reset_gc_time_stamp(); | |
| 787 if (r->continuesHumongous()) | |
| 788 return false; | |
| 789 HeapRegionRemSet* hrrs = r->rem_set(); | |
| 790 if (hrrs != NULL) hrrs->clear(); | |
| 791 // You might think here that we could clear just the cards | |
| 792 // corresponding to the used region. But no: if we leave a dirty card | |
| 793 // in a region we might allocate into, then it would prevent that card | |
| 794 // from being enqueued, and cause it to be missed. | |
| 795 // Re: the performance cost: we shouldn't be doing full GC anyway! | |
| 796 _mr_bs->clear(MemRegion(r->bottom(), r->end())); | |
| 797 return false; | |
| 798 } | |
| 799 }; | |
| 800 | |
| 801 | |
| 802 class PostMCRemSetInvalidateClosure: public HeapRegionClosure { | |
| 803 ModRefBarrierSet* _mr_bs; | |
| 804 public: | |
| 805 PostMCRemSetInvalidateClosure(ModRefBarrierSet* mr_bs) : _mr_bs(mr_bs) {} | |
| 806 bool doHeapRegion(HeapRegion* r) { | |
| 807 if (r->continuesHumongous()) return false; | |
| 808 if (r->used_region().word_size() != 0) { | |
| 809 _mr_bs->invalidate(r->used_region(), true /*whole heap*/); | |
| 810 } | |
| 811 return false; | |
| 812 } | |
| 813 }; | |
| 814 | |
| 815 void G1CollectedHeap::do_collection(bool full, bool clear_all_soft_refs, | |
| 816 size_t word_size) { | |
| 817 ResourceMark rm; | |
| 818 | |
| 819 if (full && DisableExplicitGC) { | |
| 820 gclog_or_tty->print("\n\n\nDisabling Explicit GC\n\n\n"); | |
| 821 return; | |
| 822 } | |
| 823 | |
| 824 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); | |
| 825 assert(Thread::current() == VMThread::vm_thread(), "should be in vm thread"); | |
| 826 | |
| 827 if (GC_locker::is_active()) { | |
| 828 return; // GC is disabled (e.g. JNI GetXXXCritical operation) | |
| 829 } | |
| 830 | |
| 831 { | |
| 832 IsGCActiveMark x; | |
| 833 | |
| 834 // Timing | |
| 835 gclog_or_tty->date_stamp(PrintGC && PrintGCDateStamps); | |
| 836 TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty); | |
| 837 TraceTime t(full ? "Full GC (System.gc())" : "Full GC", PrintGC, true, gclog_or_tty); | |
| 838 | |
| 839 double start = os::elapsedTime(); | |
| 840 GCOverheadReporter::recordSTWStart(start); | |
| 841 g1_policy()->record_full_collection_start(); | |
| 842 | |
| 843 gc_prologue(true); | |
| 844 increment_total_collections(); | |
| 845 | |
| 846 size_t g1h_prev_used = used(); | |
| 847 assert(used() == recalculate_used(), "Should be equal"); | |
| 848 | |
| 849 if (VerifyBeforeGC && total_collections() >= VerifyGCStartAt) { | |
| 850 HandleMark hm; // Discard invalid handles created during verification | |
| 851 prepare_for_verify(); | |
| 852 gclog_or_tty->print(" VerifyBeforeGC:"); | |
| 853 Universe::verify(true); | |
| 854 } | |
| 855 assert(regions_accounted_for(), "Region leakage!"); | |
| 856 | |
| 857 COMPILER2_PRESENT(DerivedPointerTable::clear()); | |
| 858 | |
| 859 // We want to discover references, but not process them yet. | |
| 860 // This mode is disabled in | |
| 861 // instanceRefKlass::process_discovered_references if the | |
| 862 // generation does some collection work, or | |
| 863 // instanceRefKlass::enqueue_discovered_references if the | |
| 864 // generation returns without doing any work. | |
| 865 ref_processor()->disable_discovery(); | |
| 866 ref_processor()->abandon_partial_discovery(); | |
| 867 ref_processor()->verify_no_references_recorded(); | |
| 868 | |
| 869 // Abandon current iterations of concurrent marking and concurrent | |
| 870 // refinement, if any are in progress. | |
| 871 concurrent_mark()->abort(); | |
| 872 | |
| 873 // Make sure we'll choose a new allocation region afterwards. | |
| 874 abandon_cur_alloc_region(); | |
| 875 assert(_cur_alloc_region == NULL, "Invariant."); | |
| 876 g1_rem_set()->as_HRInto_G1RemSet()->cleanupHRRS(); | |
| 877 tear_down_region_lists(); | |
| 878 set_used_regions_to_need_zero_fill(); | |
| 879 if (g1_policy()->in_young_gc_mode()) { | |
| 880 empty_young_list(); | |
| 881 g1_policy()->set_full_young_gcs(true); | |
| 882 } | |
| 883 | |
| 884 // Temporarily make reference _discovery_ single threaded (non-MT). | |
| 885 ReferenceProcessorMTMutator rp_disc_ser(ref_processor(), false); | |
| 886 | |
| 887 // Temporarily make refs discovery atomic | |
| 888 ReferenceProcessorAtomicMutator rp_disc_atomic(ref_processor(), true); | |
| 889 | |
| 890 // Temporarily clear _is_alive_non_header | |
| 891 ReferenceProcessorIsAliveMutator rp_is_alive_null(ref_processor(), NULL); | |
| 892 | |
| 893 ref_processor()->enable_discovery(); | |
|
457
27a80744a83b
6778647: snap(), snap_policy() should be renamed setup(), setup_policy()
ysr
parents:
453
diff
changeset
|
894 ref_processor()->setup_policy(clear_all_soft_refs); |
| 342 | 895 |
| 896 // Do collection work | |
| 897 { | |
| 898 HandleMark hm; // Discard invalid handles created during gc | |
| 899 G1MarkSweep::invoke_at_safepoint(ref_processor(), clear_all_soft_refs); | |
| 900 } | |
| 901 // Because freeing humongous regions may have added some unclean | |
| 902 // regions, it is necessary to tear down again before rebuilding. | |
| 903 tear_down_region_lists(); | |
| 904 rebuild_region_lists(); | |
| 905 | |
| 906 _summary_bytes_used = recalculate_used(); | |
| 907 | |
| 908 ref_processor()->enqueue_discovered_references(); | |
| 909 | |
| 910 COMPILER2_PRESENT(DerivedPointerTable::update_pointers()); | |
| 911 | |
| 912 if (VerifyAfterGC && total_collections() >= VerifyGCStartAt) { | |
| 913 HandleMark hm; // Discard invalid handles created during verification | |
| 914 gclog_or_tty->print(" VerifyAfterGC:"); | |
| 915 Universe::verify(false); | |
| 916 } | |
| 917 NOT_PRODUCT(ref_processor()->verify_no_references_recorded()); | |
| 918 | |
| 919 reset_gc_time_stamp(); | |
| 920 // Since everything potentially moved, we will clear all remembered | |
| 921 // sets, and clear all cards. Later we will also cards in the used | |
| 922 // portion of the heap after the resizing (which could be a shrinking.) | |
| 923 // We will also reset the GC time stamps of the regions. | |
| 924 PostMCRemSetClearClosure rs_clear(mr_bs()); | |
| 925 heap_region_iterate(&rs_clear); | |
| 926 | |
| 927 // Resize the heap if necessary. | |
| 928 resize_if_necessary_after_full_collection(full ? 0 : word_size); | |
| 929 | |
| 930 // Since everything potentially moved, we will clear all remembered | |
| 931 // sets, but also dirty all cards corresponding to used regions. | |
| 932 PostMCRemSetInvalidateClosure rs_invalidate(mr_bs()); | |
| 933 heap_region_iterate(&rs_invalidate); | |
| 934 if (_cg1r->use_cache()) { | |
| 935 _cg1r->clear_and_record_card_counts(); | |
| 936 _cg1r->clear_hot_cache(); | |
| 937 } | |
| 938 | |
| 939 if (PrintGC) { | |
| 940 print_size_transition(gclog_or_tty, g1h_prev_used, used(), capacity()); | |
| 941 } | |
| 942 | |
| 943 if (true) { // FIXME | |
| 944 // Ask the permanent generation to adjust size for full collections | |
| 945 perm()->compute_new_size(); | |
| 946 } | |
| 947 | |
| 948 double end = os::elapsedTime(); | |
| 949 GCOverheadReporter::recordSTWEnd(end); | |
| 950 g1_policy()->record_full_collection_end(); | |
| 951 | |
| 952 gc_epilogue(true); | |
| 953 | |
| 954 // Abandon concurrent refinement. This must happen last: in the | |
| 955 // dirty-card logging system, some cards may be dirty by weak-ref | |
| 956 // processing, and may be enqueued. But the whole card table is | |
| 957 // dirtied, so this should abandon those logs, and set "do_traversal" | |
| 958 // to true. | |
| 959 concurrent_g1_refine()->set_pya_restart(); | |
| 960 | |
| 961 assert(regions_accounted_for(), "Region leakage!"); | |
| 962 } | |
| 963 | |
| 964 if (g1_policy()->in_young_gc_mode()) { | |
| 965 _young_list->reset_sampled_info(); | |
| 966 assert( check_young_list_empty(false, false), | |
| 967 "young list should be empty at this point"); | |
| 968 } | |
| 969 } | |
| 970 | |
| 971 void G1CollectedHeap::do_full_collection(bool clear_all_soft_refs) { | |
| 972 do_collection(true, clear_all_soft_refs, 0); | |
| 973 } | |
| 974 | |
| 975 // This code is mostly copied from TenuredGeneration. | |
| 976 void | |
| 977 G1CollectedHeap:: | |
| 978 resize_if_necessary_after_full_collection(size_t word_size) { | |
| 979 assert(MinHeapFreeRatio <= MaxHeapFreeRatio, "sanity check"); | |
| 980 | |
| 981 // Include the current allocation, if any, and bytes that will be | |
| 982 // pre-allocated to support collections, as "used". | |
| 983 const size_t used_after_gc = used(); | |
| 984 const size_t capacity_after_gc = capacity(); | |
| 985 const size_t free_after_gc = capacity_after_gc - used_after_gc; | |
| 986 | |
| 987 // We don't have floating point command-line arguments | |
| 988 const double minimum_free_percentage = (double) MinHeapFreeRatio / 100; | |
| 989 const double maximum_used_percentage = 1.0 - minimum_free_percentage; | |
| 990 const double maximum_free_percentage = (double) MaxHeapFreeRatio / 100; | |
| 991 const double minimum_used_percentage = 1.0 - maximum_free_percentage; | |
| 992 | |
| 993 size_t minimum_desired_capacity = (size_t) (used_after_gc / maximum_used_percentage); | |
| 994 size_t maximum_desired_capacity = (size_t) (used_after_gc / minimum_used_percentage); | |
| 995 | |
| 996 // Don't shrink less than the initial size. | |
| 997 minimum_desired_capacity = | |
| 998 MAX2(minimum_desired_capacity, | |
| 999 collector_policy()->initial_heap_byte_size()); | |
| 1000 maximum_desired_capacity = | |
| 1001 MAX2(maximum_desired_capacity, | |
| 1002 collector_policy()->initial_heap_byte_size()); | |
| 1003 | |
| 1004 // We are failing here because minimum_desired_capacity is | |
| 1005 assert(used_after_gc <= minimum_desired_capacity, "sanity check"); | |
| 1006 assert(minimum_desired_capacity <= maximum_desired_capacity, "sanity check"); | |
| 1007 | |
| 1008 if (PrintGC && Verbose) { | |
| 1009 const double free_percentage = ((double)free_after_gc) / capacity(); | |
| 1010 gclog_or_tty->print_cr("Computing new size after full GC "); | |
| 1011 gclog_or_tty->print_cr(" " | |
| 1012 " minimum_free_percentage: %6.2f", | |
| 1013 minimum_free_percentage); | |
| 1014 gclog_or_tty->print_cr(" " | |
| 1015 " maximum_free_percentage: %6.2f", | |
| 1016 maximum_free_percentage); | |
| 1017 gclog_or_tty->print_cr(" " | |
| 1018 " capacity: %6.1fK" | |
| 1019 " minimum_desired_capacity: %6.1fK" | |
| 1020 " maximum_desired_capacity: %6.1fK", | |
| 1021 capacity() / (double) K, | |
| 1022 minimum_desired_capacity / (double) K, | |
| 1023 maximum_desired_capacity / (double) K); | |
| 1024 gclog_or_tty->print_cr(" " | |
| 1025 " free_after_gc : %6.1fK" | |
| 1026 " used_after_gc : %6.1fK", | |
| 1027 free_after_gc / (double) K, | |
| 1028 used_after_gc / (double) K); | |
| 1029 gclog_or_tty->print_cr(" " | |
| 1030 " free_percentage: %6.2f", | |
| 1031 free_percentage); | |
| 1032 } | |
| 1033 if (capacity() < minimum_desired_capacity) { | |
| 1034 // Don't expand unless it's significant | |
| 1035 size_t expand_bytes = minimum_desired_capacity - capacity_after_gc; | |
| 1036 expand(expand_bytes); | |
| 1037 if (PrintGC && Verbose) { | |
| 1038 gclog_or_tty->print_cr(" expanding:" | |
| 1039 " minimum_desired_capacity: %6.1fK" | |
| 1040 " expand_bytes: %6.1fK", | |
| 1041 minimum_desired_capacity / (double) K, | |
| 1042 expand_bytes / (double) K); | |
| 1043 } | |
| 1044 | |
| 1045 // No expansion, now see if we want to shrink | |
| 1046 } else if (capacity() > maximum_desired_capacity) { | |
| 1047 // Capacity too large, compute shrinking size | |
| 1048 size_t shrink_bytes = capacity_after_gc - maximum_desired_capacity; | |
| 1049 shrink(shrink_bytes); | |
| 1050 if (PrintGC && Verbose) { | |
| 1051 gclog_or_tty->print_cr(" " | |
| 1052 " shrinking:" | |
| 1053 " initSize: %.1fK" | |
| 1054 " maximum_desired_capacity: %.1fK", | |
| 1055 collector_policy()->initial_heap_byte_size() / (double) K, | |
| 1056 maximum_desired_capacity / (double) K); | |
| 1057 gclog_or_tty->print_cr(" " | |
| 1058 " shrink_bytes: %.1fK", | |
| 1059 shrink_bytes / (double) K); | |
| 1060 } | |
| 1061 } | |
| 1062 } | |
| 1063 | |
| 1064 | |
| 1065 HeapWord* | |
| 1066 G1CollectedHeap::satisfy_failed_allocation(size_t word_size) { | |
| 1067 HeapWord* result = NULL; | |
| 1068 | |
| 1069 // In a G1 heap, we're supposed to keep allocation from failing by | |
| 1070 // incremental pauses. Therefore, at least for now, we'll favor | |
| 1071 // expansion over collection. (This might change in the future if we can | |
| 1072 // do something smarter than full collection to satisfy a failed alloc.) | |
| 1073 | |
| 1074 result = expand_and_allocate(word_size); | |
| 1075 if (result != NULL) { | |
| 1076 assert(is_in(result), "result not in heap"); | |
| 1077 return result; | |
| 1078 } | |
| 1079 | |
| 1080 // OK, I guess we have to try collection. | |
| 1081 | |
| 1082 do_collection(false, false, word_size); | |
| 1083 | |
| 1084 result = attempt_allocation(word_size, /*permit_collection_pause*/false); | |
| 1085 | |
| 1086 if (result != NULL) { | |
| 1087 assert(is_in(result), "result not in heap"); | |
| 1088 return result; | |
| 1089 } | |
| 1090 | |
| 1091 // Try collecting soft references. | |
| 1092 do_collection(false, true, word_size); | |
| 1093 result = attempt_allocation(word_size, /*permit_collection_pause*/false); | |
| 1094 if (result != NULL) { | |
| 1095 assert(is_in(result), "result not in heap"); | |
| 1096 return result; | |
| 1097 } | |
| 1098 | |
| 1099 // What else? We might try synchronous finalization later. If the total | |
| 1100 // space available is large enough for the allocation, then a more | |
| 1101 // complete compaction phase than we've tried so far might be | |
| 1102 // appropriate. | |
| 1103 return NULL; | |
| 1104 } | |
| 1105 | |
| 1106 // Attempting to expand the heap sufficiently | |
| 1107 // to support an allocation of the given "word_size". If | |
| 1108 // successful, perform the allocation and return the address of the | |
| 1109 // allocated block, or else "NULL". | |
| 1110 | |
| 1111 HeapWord* G1CollectedHeap::expand_and_allocate(size_t word_size) { | |
| 1112 size_t expand_bytes = word_size * HeapWordSize; | |
| 1113 if (expand_bytes < MinHeapDeltaBytes) { | |
| 1114 expand_bytes = MinHeapDeltaBytes; | |
| 1115 } | |
| 1116 expand(expand_bytes); | |
| 1117 assert(regions_accounted_for(), "Region leakage!"); | |
| 1118 HeapWord* result = attempt_allocation(word_size, false /* permit_collection_pause */); | |
| 1119 return result; | |
| 1120 } | |
| 1121 | |
| 1122 size_t G1CollectedHeap::free_region_if_totally_empty(HeapRegion* hr) { | |
| 1123 size_t pre_used = 0; | |
| 1124 size_t cleared_h_regions = 0; | |
| 1125 size_t freed_regions = 0; | |
| 1126 UncleanRegionList local_list; | |
| 1127 free_region_if_totally_empty_work(hr, pre_used, cleared_h_regions, | |
| 1128 freed_regions, &local_list); | |
| 1129 | |
| 1130 finish_free_region_work(pre_used, cleared_h_regions, freed_regions, | |
| 1131 &local_list); | |
| 1132 return pre_used; | |
| 1133 } | |
| 1134 | |
| 1135 void | |
| 1136 G1CollectedHeap::free_region_if_totally_empty_work(HeapRegion* hr, | |
| 1137 size_t& pre_used, | |
| 1138 size_t& cleared_h, | |
| 1139 size_t& freed_regions, | |
| 1140 UncleanRegionList* list, | |
| 1141 bool par) { | |
| 1142 assert(!hr->continuesHumongous(), "should have filtered these out"); | |
| 1143 size_t res = 0; | |
| 1144 if (!hr->popular() && hr->used() > 0 && hr->garbage_bytes() == hr->used()) { | |
| 1145 if (!hr->is_young()) { | |
| 1146 if (G1PolicyVerbose > 0) | |
| 1147 gclog_or_tty->print_cr("Freeing empty region "PTR_FORMAT "(" SIZE_FORMAT " bytes)" | |
| 1148 " during cleanup", hr, hr->used()); | |
| 1149 free_region_work(hr, pre_used, cleared_h, freed_regions, list, par); | |
| 1150 } | |
| 1151 } | |
| 1152 } | |
| 1153 | |
| 1154 // FIXME: both this and shrink could probably be more efficient by | |
| 1155 // doing one "VirtualSpace::expand_by" call rather than several. | |
| 1156 void G1CollectedHeap::expand(size_t expand_bytes) { | |
| 1157 size_t old_mem_size = _g1_storage.committed_size(); | |
| 1158 // We expand by a minimum of 1K. | |
| 1159 expand_bytes = MAX2(expand_bytes, (size_t)K); | |
| 1160 size_t aligned_expand_bytes = | |
| 1161 ReservedSpace::page_align_size_up(expand_bytes); | |
| 1162 aligned_expand_bytes = align_size_up(aligned_expand_bytes, | |
| 1163 HeapRegion::GrainBytes); | |
| 1164 expand_bytes = aligned_expand_bytes; | |
| 1165 while (expand_bytes > 0) { | |
| 1166 HeapWord* base = (HeapWord*)_g1_storage.high(); | |
| 1167 // Commit more storage. | |
| 1168 bool successful = _g1_storage.expand_by(HeapRegion::GrainBytes); | |
| 1169 if (!successful) { | |
| 1170 expand_bytes = 0; | |
| 1171 } else { | |
| 1172 expand_bytes -= HeapRegion::GrainBytes; | |
| 1173 // Expand the committed region. | |
| 1174 HeapWord* high = (HeapWord*) _g1_storage.high(); | |
| 1175 _g1_committed.set_end(high); | |
| 1176 // Create a new HeapRegion. | |
| 1177 MemRegion mr(base, high); | |
| 1178 bool is_zeroed = !_g1_max_committed.contains(base); | |
| 1179 HeapRegion* hr = new HeapRegion(_bot_shared, mr, is_zeroed); | |
| 1180 | |
| 1181 // Now update max_committed if necessary. | |
| 1182 _g1_max_committed.set_end(MAX2(_g1_max_committed.end(), high)); | |
| 1183 | |
| 1184 // Add it to the HeapRegionSeq. | |
| 1185 _hrs->insert(hr); | |
| 1186 // Set the zero-fill state, according to whether it's already | |
| 1187 // zeroed. | |
| 1188 { | |
| 1189 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 1190 if (is_zeroed) { | |
| 1191 hr->set_zero_fill_complete(); | |
| 1192 put_free_region_on_list_locked(hr); | |
| 1193 } else { | |
| 1194 hr->set_zero_fill_needed(); | |
| 1195 put_region_on_unclean_list_locked(hr); | |
| 1196 } | |
| 1197 } | |
| 1198 _free_regions++; | |
| 1199 // And we used up an expansion region to create it. | |
| 1200 _expansion_regions--; | |
| 1201 // Tell the cardtable about it. | |
| 1202 Universe::heap()->barrier_set()->resize_covered_region(_g1_committed); | |
| 1203 // And the offset table as well. | |
| 1204 _bot_shared->resize(_g1_committed.word_size()); | |
| 1205 } | |
| 1206 } | |
| 1207 if (Verbose && PrintGC) { | |
| 1208 size_t new_mem_size = _g1_storage.committed_size(); | |
| 1209 gclog_or_tty->print_cr("Expanding garbage-first heap from %ldK by %ldK to %ldK", | |
| 1210 old_mem_size/K, aligned_expand_bytes/K, | |
| 1211 new_mem_size/K); | |
| 1212 } | |
| 1213 } | |
| 1214 | |
| 1215 void G1CollectedHeap::shrink_helper(size_t shrink_bytes) | |
| 1216 { | |
| 1217 size_t old_mem_size = _g1_storage.committed_size(); | |
| 1218 size_t aligned_shrink_bytes = | |
| 1219 ReservedSpace::page_align_size_down(shrink_bytes); | |
| 1220 aligned_shrink_bytes = align_size_down(aligned_shrink_bytes, | |
| 1221 HeapRegion::GrainBytes); | |
| 1222 size_t num_regions_deleted = 0; | |
| 1223 MemRegion mr = _hrs->shrink_by(aligned_shrink_bytes, num_regions_deleted); | |
| 1224 | |
| 1225 assert(mr.end() == (HeapWord*)_g1_storage.high(), "Bad shrink!"); | |
| 1226 if (mr.byte_size() > 0) | |
| 1227 _g1_storage.shrink_by(mr.byte_size()); | |
| 1228 assert(mr.start() == (HeapWord*)_g1_storage.high(), "Bad shrink!"); | |
| 1229 | |
| 1230 _g1_committed.set_end(mr.start()); | |
| 1231 _free_regions -= num_regions_deleted; | |
| 1232 _expansion_regions += num_regions_deleted; | |
| 1233 | |
| 1234 // Tell the cardtable about it. | |
| 1235 Universe::heap()->barrier_set()->resize_covered_region(_g1_committed); | |
| 1236 | |
| 1237 // And the offset table as well. | |
| 1238 _bot_shared->resize(_g1_committed.word_size()); | |
| 1239 | |
| 1240 HeapRegionRemSet::shrink_heap(n_regions()); | |
| 1241 | |
| 1242 if (Verbose && PrintGC) { | |
| 1243 size_t new_mem_size = _g1_storage.committed_size(); | |
| 1244 gclog_or_tty->print_cr("Shrinking garbage-first heap from %ldK by %ldK to %ldK", | |
| 1245 old_mem_size/K, aligned_shrink_bytes/K, | |
| 1246 new_mem_size/K); | |
| 1247 } | |
| 1248 } | |
| 1249 | |
| 1250 void G1CollectedHeap::shrink(size_t shrink_bytes) { | |
| 1251 release_gc_alloc_regions(); | |
| 1252 tear_down_region_lists(); // We will rebuild them in a moment. | |
| 1253 shrink_helper(shrink_bytes); | |
| 1254 rebuild_region_lists(); | |
| 1255 } | |
| 1256 | |
| 1257 // Public methods. | |
| 1258 | |
| 1259 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away | |
| 1260 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list | |
| 1261 #endif // _MSC_VER | |
| 1262 | |
| 1263 | |
| 1264 G1CollectedHeap::G1CollectedHeap(G1CollectorPolicy* policy_) : | |
| 1265 SharedHeap(policy_), | |
| 1266 _g1_policy(policy_), | |
| 1267 _ref_processor(NULL), | |
| 1268 _process_strong_tasks(new SubTasksDone(G1H_PS_NumElements)), | |
| 1269 _bot_shared(NULL), | |
| 1270 _par_alloc_during_gc_lock(Mutex::leaf, "par alloc during GC lock"), | |
| 1271 _objs_with_preserved_marks(NULL), _preserved_marks_of_objs(NULL), | |
| 1272 _evac_failure_scan_stack(NULL) , | |
| 1273 _mark_in_progress(false), | |
| 1274 _cg1r(NULL), _czft(NULL), _summary_bytes_used(0), | |
| 1275 _cur_alloc_region(NULL), | |
| 1276 _refine_cte_cl(NULL), | |
| 1277 _free_region_list(NULL), _free_region_list_size(0), | |
| 1278 _free_regions(0), | |
| 1279 _popular_object_boundary(NULL), | |
| 1280 _cur_pop_hr_index(0), | |
| 1281 _popular_regions_to_be_evacuated(NULL), | |
| 1282 _pop_obj_rc_at_copy(), | |
| 1283 _full_collection(false), | |
| 1284 _unclean_region_list(), | |
| 1285 _unclean_regions_coming(false), | |
| 1286 _young_list(new YoungList(this)), | |
| 1287 _gc_time_stamp(0), | |
| 1288 _surviving_young_words(NULL) | |
| 1289 { | |
| 1290 _g1h = this; // To catch bugs. | |
| 1291 if (_process_strong_tasks == NULL || !_process_strong_tasks->valid()) { | |
| 1292 vm_exit_during_initialization("Failed necessary allocation."); | |
| 1293 } | |
| 1294 int n_queues = MAX2((int)ParallelGCThreads, 1); | |
| 1295 _task_queues = new RefToScanQueueSet(n_queues); | |
| 1296 | |
| 1297 int n_rem_sets = HeapRegionRemSet::num_par_rem_sets(); | |
| 1298 assert(n_rem_sets > 0, "Invariant."); | |
| 1299 | |
| 1300 HeapRegionRemSetIterator** iter_arr = | |
| 1301 NEW_C_HEAP_ARRAY(HeapRegionRemSetIterator*, n_queues); | |
| 1302 for (int i = 0; i < n_queues; i++) { | |
| 1303 iter_arr[i] = new HeapRegionRemSetIterator(); | |
| 1304 } | |
| 1305 _rem_set_iterator = iter_arr; | |
| 1306 | |
| 1307 for (int i = 0; i < n_queues; i++) { | |
| 1308 RefToScanQueue* q = new RefToScanQueue(); | |
| 1309 q->initialize(); | |
| 1310 _task_queues->register_queue(i, q); | |
| 1311 } | |
| 1312 | |
| 1313 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) { | |
| 1314 _gc_alloc_regions[ap] = NULL; | |
| 1315 _gc_alloc_region_counts[ap] = 0; | |
| 1316 } | |
| 1317 guarantee(_task_queues != NULL, "task_queues allocation failure."); | |
| 1318 } | |
| 1319 | |
| 1320 jint G1CollectedHeap::initialize() { | |
| 1321 os::enable_vtime(); | |
| 1322 | |
| 1323 // Necessary to satisfy locking discipline assertions. | |
| 1324 | |
| 1325 MutexLocker x(Heap_lock); | |
| 1326 | |
| 1327 // While there are no constraints in the GC code that HeapWordSize | |
| 1328 // be any particular value, there are multiple other areas in the | |
| 1329 // system which believe this to be true (e.g. oop->object_size in some | |
| 1330 // cases incorrectly returns the size in wordSize units rather than | |
| 1331 // HeapWordSize). | |
| 1332 guarantee(HeapWordSize == wordSize, "HeapWordSize must equal wordSize"); | |
| 1333 | |
| 1334 size_t init_byte_size = collector_policy()->initial_heap_byte_size(); | |
| 1335 size_t max_byte_size = collector_policy()->max_heap_byte_size(); | |
| 1336 | |
| 1337 // Ensure that the sizes are properly aligned. | |
| 1338 Universe::check_alignment(init_byte_size, HeapRegion::GrainBytes, "g1 heap"); | |
| 1339 Universe::check_alignment(max_byte_size, HeapRegion::GrainBytes, "g1 heap"); | |
| 1340 | |
| 1341 // We allocate this in any case, but only do no work if the command line | |
| 1342 // param is off. | |
| 1343 _cg1r = new ConcurrentG1Refine(); | |
| 1344 | |
| 1345 // Reserve the maximum. | |
| 1346 PermanentGenerationSpec* pgs = collector_policy()->permanent_generation(); | |
| 1347 // Includes the perm-gen. | |
| 1348 ReservedSpace heap_rs(max_byte_size + pgs->max_size(), | |
| 1349 HeapRegion::GrainBytes, | |
| 1350 false /*ism*/); | |
| 1351 | |
| 1352 if (!heap_rs.is_reserved()) { | |
| 1353 vm_exit_during_initialization("Could not reserve enough space for object heap"); | |
| 1354 return JNI_ENOMEM; | |
| 1355 } | |
| 1356 | |
| 1357 // It is important to do this in a way such that concurrent readers can't | |
| 1358 // temporarily think somethings in the heap. (I've actually seen this | |
| 1359 // happen in asserts: DLD.) | |
| 1360 _reserved.set_word_size(0); | |
| 1361 _reserved.set_start((HeapWord*)heap_rs.base()); | |
| 1362 _reserved.set_end((HeapWord*)(heap_rs.base() + heap_rs.size())); | |
| 1363 | |
| 1364 _expansion_regions = max_byte_size/HeapRegion::GrainBytes; | |
| 1365 | |
| 1366 _num_humongous_regions = 0; | |
| 1367 | |
| 1368 // Create the gen rem set (and barrier set) for the entire reserved region. | |
| 1369 _rem_set = collector_policy()->create_rem_set(_reserved, 2); | |
| 1370 set_barrier_set(rem_set()->bs()); | |
| 1371 if (barrier_set()->is_a(BarrierSet::ModRef)) { | |
| 1372 _mr_bs = (ModRefBarrierSet*)_barrier_set; | |
| 1373 } else { | |
| 1374 vm_exit_during_initialization("G1 requires a mod ref bs."); | |
| 1375 return JNI_ENOMEM; | |
| 1376 } | |
| 1377 | |
| 1378 // Also create a G1 rem set. | |
| 1379 if (G1UseHRIntoRS) { | |
| 1380 if (mr_bs()->is_a(BarrierSet::CardTableModRef)) { | |
| 1381 _g1_rem_set = new HRInto_G1RemSet(this, (CardTableModRefBS*)mr_bs()); | |
| 1382 } else { | |
| 1383 vm_exit_during_initialization("G1 requires a cardtable mod ref bs."); | |
| 1384 return JNI_ENOMEM; | |
| 1385 } | |
| 1386 } else { | |
| 1387 _g1_rem_set = new StupidG1RemSet(this); | |
| 1388 } | |
| 1389 | |
| 1390 // Carve out the G1 part of the heap. | |
| 1391 | |
| 1392 ReservedSpace g1_rs = heap_rs.first_part(max_byte_size); | |
| 1393 _g1_reserved = MemRegion((HeapWord*)g1_rs.base(), | |
| 1394 g1_rs.size()/HeapWordSize); | |
| 1395 ReservedSpace perm_gen_rs = heap_rs.last_part(max_byte_size); | |
| 1396 | |
| 1397 _perm_gen = pgs->init(perm_gen_rs, pgs->init_size(), rem_set()); | |
| 1398 | |
| 1399 _g1_storage.initialize(g1_rs, 0); | |
| 1400 _g1_committed = MemRegion((HeapWord*)_g1_storage.low(), (size_t) 0); | |
| 1401 _g1_max_committed = _g1_committed; | |
| 393 | 1402 _hrs = new HeapRegionSeq(_expansion_regions); |
| 342 | 1403 guarantee(_hrs != NULL, "Couldn't allocate HeapRegionSeq"); |
| 1404 guarantee(_cur_alloc_region == NULL, "from constructor"); | |
| 1405 | |
| 1406 _bot_shared = new G1BlockOffsetSharedArray(_reserved, | |
| 1407 heap_word_size(init_byte_size)); | |
| 1408 | |
| 1409 _g1h = this; | |
| 1410 | |
| 1411 // Create the ConcurrentMark data structure and thread. | |
| 1412 // (Must do this late, so that "max_regions" is defined.) | |
| 1413 _cm = new ConcurrentMark(heap_rs, (int) max_regions()); | |
| 1414 _cmThread = _cm->cmThread(); | |
| 1415 | |
| 1416 // ...and the concurrent zero-fill thread, if necessary. | |
| 1417 if (G1ConcZeroFill) { | |
| 1418 _czft = new ConcurrentZFThread(); | |
| 1419 } | |
| 1420 | |
| 1421 | |
| 1422 | |
| 1423 // Allocate the popular regions; take them off free lists. | |
| 1424 size_t pop_byte_size = G1NumPopularRegions * HeapRegion::GrainBytes; | |
| 1425 expand(pop_byte_size); | |
| 1426 _popular_object_boundary = | |
| 1427 _g1_reserved.start() + (G1NumPopularRegions * HeapRegion::GrainWords); | |
| 1428 for (int i = 0; i < G1NumPopularRegions; i++) { | |
| 1429 HeapRegion* hr = newAllocRegion(HeapRegion::GrainWords); | |
| 1430 // assert(hr != NULL && hr->bottom() < _popular_object_boundary, | |
| 1431 // "Should be enough, and all should be below boundary."); | |
| 1432 hr->set_popular(true); | |
| 1433 } | |
| 1434 assert(_cur_pop_hr_index == 0, "Start allocating at the first region."); | |
| 1435 | |
| 1436 // Initialize the from_card cache structure of HeapRegionRemSet. | |
| 1437 HeapRegionRemSet::init_heap(max_regions()); | |
| 1438 | |
| 1439 // Now expand into the rest of the initial heap size. | |
| 1440 expand(init_byte_size - pop_byte_size); | |
| 1441 | |
| 1442 // Perform any initialization actions delegated to the policy. | |
| 1443 g1_policy()->init(); | |
| 1444 | |
| 1445 g1_policy()->note_start_of_mark_thread(); | |
| 1446 | |
| 1447 _refine_cte_cl = | |
| 1448 new RefineCardTableEntryClosure(ConcurrentG1RefineThread::sts(), | |
| 1449 g1_rem_set(), | |
| 1450 concurrent_g1_refine()); | |
| 1451 JavaThread::dirty_card_queue_set().set_closure(_refine_cte_cl); | |
| 1452 | |
| 1453 JavaThread::satb_mark_queue_set().initialize(SATB_Q_CBL_mon, | |
| 1454 SATB_Q_FL_lock, | |
| 1455 0, | |
| 1456 Shared_SATB_Q_lock); | |
| 1457 if (G1RSBarrierUseQueue) { | |
| 1458 JavaThread::dirty_card_queue_set().initialize(DirtyCardQ_CBL_mon, | |
| 1459 DirtyCardQ_FL_lock, | |
| 1460 G1DirtyCardQueueMax, | |
| 1461 Shared_DirtyCardQ_lock); | |
| 1462 } | |
| 1463 // In case we're keeping closure specialization stats, initialize those | |
| 1464 // counts and that mechanism. | |
| 1465 SpecializationStats::clear(); | |
| 1466 | |
| 1467 _gc_alloc_region_list = NULL; | |
| 1468 | |
| 1469 // Do later initialization work for concurrent refinement. | |
| 1470 _cg1r->init(); | |
| 1471 | |
| 1472 const char* group_names[] = { "CR", "ZF", "CM", "CL" }; | |
| 1473 GCOverheadReporter::initGCOverheadReporter(4, group_names); | |
| 1474 | |
| 1475 return JNI_OK; | |
| 1476 } | |
| 1477 | |
| 1478 void G1CollectedHeap::ref_processing_init() { | |
| 1479 SharedHeap::ref_processing_init(); | |
| 1480 MemRegion mr = reserved_region(); | |
| 1481 _ref_processor = ReferenceProcessor::create_ref_processor( | |
| 1482 mr, // span | |
| 1483 false, // Reference discovery is not atomic | |
| 1484 // (though it shouldn't matter here.) | |
| 1485 true, // mt_discovery | |
| 1486 NULL, // is alive closure: need to fill this in for efficiency | |
| 1487 ParallelGCThreads, | |
| 1488 ParallelRefProcEnabled, | |
| 1489 true); // Setting next fields of discovered | |
| 1490 // lists requires a barrier. | |
| 1491 } | |
| 1492 | |
| 1493 size_t G1CollectedHeap::capacity() const { | |
| 1494 return _g1_committed.byte_size(); | |
| 1495 } | |
| 1496 | |
| 1497 void G1CollectedHeap::iterate_dirty_card_closure(bool concurrent, | |
| 1498 int worker_i) { | |
| 1499 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 1500 int n_completed_buffers = 0; | |
| 1501 while (dcqs.apply_closure_to_completed_buffer(worker_i, 0, true)) { | |
| 1502 n_completed_buffers++; | |
| 1503 } | |
| 1504 g1_policy()->record_update_rs_processed_buffers(worker_i, | |
| 1505 (double) n_completed_buffers); | |
| 1506 dcqs.clear_n_completed_buffers(); | |
| 1507 // Finish up the queue... | |
| 1508 if (worker_i == 0) concurrent_g1_refine()->clean_up_cache(worker_i, | |
| 1509 g1_rem_set()); | |
| 1510 assert(!dcqs.completed_buffers_exist_dirty(), "Completed buffers exist!"); | |
| 1511 } | |
| 1512 | |
| 1513 | |
| 1514 // Computes the sum of the storage used by the various regions. | |
| 1515 | |
| 1516 size_t G1CollectedHeap::used() const { | |
| 1517 assert(Heap_lock->owner() != NULL, | |
| 1518 "Should be owned on this thread's behalf."); | |
| 1519 size_t result = _summary_bytes_used; | |
| 1520 if (_cur_alloc_region != NULL) | |
| 1521 result += _cur_alloc_region->used(); | |
| 1522 return result; | |
| 1523 } | |
| 1524 | |
| 1525 class SumUsedClosure: public HeapRegionClosure { | |
| 1526 size_t _used; | |
| 1527 public: | |
| 1528 SumUsedClosure() : _used(0) {} | |
| 1529 bool doHeapRegion(HeapRegion* r) { | |
| 1530 if (!r->continuesHumongous()) { | |
| 1531 _used += r->used(); | |
| 1532 } | |
| 1533 return false; | |
| 1534 } | |
| 1535 size_t result() { return _used; } | |
| 1536 }; | |
| 1537 | |
| 1538 size_t G1CollectedHeap::recalculate_used() const { | |
| 1539 SumUsedClosure blk; | |
| 1540 _hrs->iterate(&blk); | |
| 1541 return blk.result(); | |
| 1542 } | |
| 1543 | |
| 1544 #ifndef PRODUCT | |
| 1545 class SumUsedRegionsClosure: public HeapRegionClosure { | |
| 1546 size_t _num; | |
| 1547 public: | |
| 1548 // _num is set to 1 to account for the popular region | |
| 1549 SumUsedRegionsClosure() : _num(G1NumPopularRegions) {} | |
| 1550 bool doHeapRegion(HeapRegion* r) { | |
| 1551 if (r->continuesHumongous() || r->used() > 0 || r->is_gc_alloc_region()) { | |
| 1552 _num += 1; | |
| 1553 } | |
| 1554 return false; | |
| 1555 } | |
| 1556 size_t result() { return _num; } | |
| 1557 }; | |
| 1558 | |
| 1559 size_t G1CollectedHeap::recalculate_used_regions() const { | |
| 1560 SumUsedRegionsClosure blk; | |
| 1561 _hrs->iterate(&blk); | |
| 1562 return blk.result(); | |
| 1563 } | |
| 1564 #endif // PRODUCT | |
| 1565 | |
| 1566 size_t G1CollectedHeap::unsafe_max_alloc() { | |
| 1567 if (_free_regions > 0) return HeapRegion::GrainBytes; | |
| 1568 // otherwise, is there space in the current allocation region? | |
| 1569 | |
| 1570 // We need to store the current allocation region in a local variable | |
| 1571 // here. The problem is that this method doesn't take any locks and | |
| 1572 // there may be other threads which overwrite the current allocation | |
| 1573 // region field. attempt_allocation(), for example, sets it to NULL | |
| 1574 // and this can happen *after* the NULL check here but before the call | |
| 1575 // to free(), resulting in a SIGSEGV. Note that this doesn't appear | |
| 1576 // to be a problem in the optimized build, since the two loads of the | |
| 1577 // current allocation region field are optimized away. | |
| 1578 HeapRegion* car = _cur_alloc_region; | |
| 1579 | |
| 1580 // FIXME: should iterate over all regions? | |
| 1581 if (car == NULL) { | |
| 1582 return 0; | |
| 1583 } | |
| 1584 return car->free(); | |
| 1585 } | |
| 1586 | |
| 1587 void G1CollectedHeap::collect(GCCause::Cause cause) { | |
| 1588 // The caller doesn't have the Heap_lock | |
| 1589 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); | |
| 1590 MutexLocker ml(Heap_lock); | |
| 1591 collect_locked(cause); | |
| 1592 } | |
| 1593 | |
| 1594 void G1CollectedHeap::collect_as_vm_thread(GCCause::Cause cause) { | |
| 1595 assert(Thread::current()->is_VM_thread(), "Precondition#1"); | |
| 1596 assert(Heap_lock->is_locked(), "Precondition#2"); | |
| 1597 GCCauseSetter gcs(this, cause); | |
| 1598 switch (cause) { | |
| 1599 case GCCause::_heap_inspection: | |
| 1600 case GCCause::_heap_dump: { | |
| 1601 HandleMark hm; | |
| 1602 do_full_collection(false); // don't clear all soft refs | |
| 1603 break; | |
| 1604 } | |
| 1605 default: // XXX FIX ME | |
| 1606 ShouldNotReachHere(); // Unexpected use of this function | |
| 1607 } | |
| 1608 } | |
| 1609 | |
| 1610 | |
| 1611 void G1CollectedHeap::collect_locked(GCCause::Cause cause) { | |
| 1612 // Don't want to do a GC until cleanup is completed. | |
| 1613 wait_for_cleanup_complete(); | |
| 1614 | |
| 1615 // Read the GC count while holding the Heap_lock | |
| 1616 int gc_count_before = SharedHeap::heap()->total_collections(); | |
| 1617 { | |
| 1618 MutexUnlocker mu(Heap_lock); // give up heap lock, execute gets it back | |
| 1619 VM_G1CollectFull op(gc_count_before, cause); | |
| 1620 VMThread::execute(&op); | |
| 1621 } | |
| 1622 } | |
| 1623 | |
| 1624 bool G1CollectedHeap::is_in(const void* p) const { | |
| 1625 if (_g1_committed.contains(p)) { | |
| 1626 HeapRegion* hr = _hrs->addr_to_region(p); | |
| 1627 return hr->is_in(p); | |
| 1628 } else { | |
| 1629 return _perm_gen->as_gen()->is_in(p); | |
| 1630 } | |
| 1631 } | |
| 1632 | |
| 1633 // Iteration functions. | |
| 1634 | |
| 1635 // Iterates an OopClosure over all ref-containing fields of objects | |
| 1636 // within a HeapRegion. | |
| 1637 | |
| 1638 class IterateOopClosureRegionClosure: public HeapRegionClosure { | |
| 1639 MemRegion _mr; | |
| 1640 OopClosure* _cl; | |
| 1641 public: | |
| 1642 IterateOopClosureRegionClosure(MemRegion mr, OopClosure* cl) | |
| 1643 : _mr(mr), _cl(cl) {} | |
| 1644 bool doHeapRegion(HeapRegion* r) { | |
| 1645 if (! r->continuesHumongous()) { | |
| 1646 r->oop_iterate(_cl); | |
| 1647 } | |
| 1648 return false; | |
| 1649 } | |
| 1650 }; | |
| 1651 | |
| 1652 void G1CollectedHeap::oop_iterate(OopClosure* cl) { | |
| 1653 IterateOopClosureRegionClosure blk(_g1_committed, cl); | |
| 1654 _hrs->iterate(&blk); | |
| 1655 } | |
| 1656 | |
| 1657 void G1CollectedHeap::oop_iterate(MemRegion mr, OopClosure* cl) { | |
| 1658 IterateOopClosureRegionClosure blk(mr, cl); | |
| 1659 _hrs->iterate(&blk); | |
| 1660 } | |
| 1661 | |
| 1662 // Iterates an ObjectClosure over all objects within a HeapRegion. | |
| 1663 | |
| 1664 class IterateObjectClosureRegionClosure: public HeapRegionClosure { | |
| 1665 ObjectClosure* _cl; | |
| 1666 public: | |
| 1667 IterateObjectClosureRegionClosure(ObjectClosure* cl) : _cl(cl) {} | |
| 1668 bool doHeapRegion(HeapRegion* r) { | |
| 1669 if (! r->continuesHumongous()) { | |
| 1670 r->object_iterate(_cl); | |
| 1671 } | |
| 1672 return false; | |
| 1673 } | |
| 1674 }; | |
| 1675 | |
| 1676 void G1CollectedHeap::object_iterate(ObjectClosure* cl) { | |
| 1677 IterateObjectClosureRegionClosure blk(cl); | |
| 1678 _hrs->iterate(&blk); | |
| 1679 } | |
| 1680 | |
| 1681 void G1CollectedHeap::object_iterate_since_last_GC(ObjectClosure* cl) { | |
| 1682 // FIXME: is this right? | |
| 1683 guarantee(false, "object_iterate_since_last_GC not supported by G1 heap"); | |
| 1684 } | |
| 1685 | |
| 1686 // Calls a SpaceClosure on a HeapRegion. | |
| 1687 | |
| 1688 class SpaceClosureRegionClosure: public HeapRegionClosure { | |
| 1689 SpaceClosure* _cl; | |
| 1690 public: | |
| 1691 SpaceClosureRegionClosure(SpaceClosure* cl) : _cl(cl) {} | |
| 1692 bool doHeapRegion(HeapRegion* r) { | |
| 1693 _cl->do_space(r); | |
| 1694 return false; | |
| 1695 } | |
| 1696 }; | |
| 1697 | |
| 1698 void G1CollectedHeap::space_iterate(SpaceClosure* cl) { | |
| 1699 SpaceClosureRegionClosure blk(cl); | |
| 1700 _hrs->iterate(&blk); | |
| 1701 } | |
| 1702 | |
| 1703 void G1CollectedHeap::heap_region_iterate(HeapRegionClosure* cl) { | |
| 1704 _hrs->iterate(cl); | |
| 1705 } | |
| 1706 | |
| 1707 void G1CollectedHeap::heap_region_iterate_from(HeapRegion* r, | |
| 1708 HeapRegionClosure* cl) { | |
| 1709 _hrs->iterate_from(r, cl); | |
| 1710 } | |
| 1711 | |
| 1712 void | |
| 1713 G1CollectedHeap::heap_region_iterate_from(int idx, HeapRegionClosure* cl) { | |
| 1714 _hrs->iterate_from(idx, cl); | |
| 1715 } | |
| 1716 | |
| 1717 HeapRegion* G1CollectedHeap::region_at(size_t idx) { return _hrs->at(idx); } | |
| 1718 | |
| 1719 void | |
| 1720 G1CollectedHeap::heap_region_par_iterate_chunked(HeapRegionClosure* cl, | |
| 1721 int worker, | |
| 1722 jint claim_value) { | |
| 355 | 1723 const size_t regions = n_regions(); |
| 1724 const size_t worker_num = (ParallelGCThreads > 0 ? ParallelGCThreads : 1); | |
| 1725 // try to spread out the starting points of the workers | |
| 1726 const size_t start_index = regions / worker_num * (size_t) worker; | |
| 1727 | |
| 1728 // each worker will actually look at all regions | |
| 1729 for (size_t count = 0; count < regions; ++count) { | |
| 1730 const size_t index = (start_index + count) % regions; | |
| 1731 assert(0 <= index && index < regions, "sanity"); | |
| 1732 HeapRegion* r = region_at(index); | |
| 1733 // we'll ignore "continues humongous" regions (we'll process them | |
| 1734 // when we come across their corresponding "start humongous" | |
| 1735 // region) and regions already claimed | |
| 1736 if (r->claim_value() == claim_value || r->continuesHumongous()) { | |
| 1737 continue; | |
| 1738 } | |
| 1739 // OK, try to claim it | |
| 342 | 1740 if (r->claimHeapRegion(claim_value)) { |
| 355 | 1741 // success! |
| 1742 assert(!r->continuesHumongous(), "sanity"); | |
| 1743 if (r->startsHumongous()) { | |
| 1744 // If the region is "starts humongous" we'll iterate over its | |
| 1745 // "continues humongous" first; in fact we'll do them | |
| 1746 // first. The order is important. In on case, calling the | |
| 1747 // closure on the "starts humongous" region might de-allocate | |
| 1748 // and clear all its "continues humongous" regions and, as a | |
| 1749 // result, we might end up processing them twice. So, we'll do | |
| 1750 // them first (notice: most closures will ignore them anyway) and | |
| 1751 // then we'll do the "starts humongous" region. | |
| 1752 for (size_t ch_index = index + 1; ch_index < regions; ++ch_index) { | |
| 1753 HeapRegion* chr = region_at(ch_index); | |
| 1754 | |
| 1755 // if the region has already been claimed or it's not | |
| 1756 // "continues humongous" we're done | |
| 1757 if (chr->claim_value() == claim_value || | |
| 1758 !chr->continuesHumongous()) { | |
| 1759 break; | |
| 1760 } | |
| 1761 | |
| 1762 // Noone should have claimed it directly. We can given | |
| 1763 // that we claimed its "starts humongous" region. | |
| 1764 assert(chr->claim_value() != claim_value, "sanity"); | |
| 1765 assert(chr->humongous_start_region() == r, "sanity"); | |
| 1766 | |
| 1767 if (chr->claimHeapRegion(claim_value)) { | |
| 1768 // we should always be able to claim it; noone else should | |
| 1769 // be trying to claim this region | |
| 1770 | |
| 1771 bool res2 = cl->doHeapRegion(chr); | |
| 1772 assert(!res2, "Should not abort"); | |
| 1773 | |
| 1774 // Right now, this holds (i.e., no closure that actually | |
| 1775 // does something with "continues humongous" regions | |
| 1776 // clears them). We might have to weaken it in the future, | |
| 1777 // but let's leave these two asserts here for extra safety. | |
| 1778 assert(chr->continuesHumongous(), "should still be the case"); | |
| 1779 assert(chr->humongous_start_region() == r, "sanity"); | |
| 1780 } else { | |
| 1781 guarantee(false, "we should not reach here"); | |
| 1782 } | |
| 1783 } | |
| 1784 } | |
| 1785 | |
| 1786 assert(!r->continuesHumongous(), "sanity"); | |
| 1787 bool res = cl->doHeapRegion(r); | |
| 1788 assert(!res, "Should not abort"); | |
| 1789 } | |
| 1790 } | |
| 1791 } | |
| 1792 | |
| 390 | 1793 class ResetClaimValuesClosure: public HeapRegionClosure { |
| 1794 public: | |
| 1795 bool doHeapRegion(HeapRegion* r) { | |
| 1796 r->set_claim_value(HeapRegion::InitialClaimValue); | |
| 1797 return false; | |
| 1798 } | |
| 1799 }; | |
| 1800 | |
| 1801 void | |
| 1802 G1CollectedHeap::reset_heap_region_claim_values() { | |
| 1803 ResetClaimValuesClosure blk; | |
| 1804 heap_region_iterate(&blk); | |
| 1805 } | |
| 1806 | |
| 355 | 1807 #ifdef ASSERT |
| 1808 // This checks whether all regions in the heap have the correct claim | |
| 1809 // value. I also piggy-backed on this a check to ensure that the | |
| 1810 // humongous_start_region() information on "continues humongous" | |
| 1811 // regions is correct. | |
| 1812 | |
| 1813 class CheckClaimValuesClosure : public HeapRegionClosure { | |
| 1814 private: | |
| 1815 jint _claim_value; | |
| 1816 size_t _failures; | |
| 1817 HeapRegion* _sh_region; | |
| 1818 public: | |
| 1819 CheckClaimValuesClosure(jint claim_value) : | |
| 1820 _claim_value(claim_value), _failures(0), _sh_region(NULL) { } | |
| 1821 bool doHeapRegion(HeapRegion* r) { | |
| 1822 if (r->claim_value() != _claim_value) { | |
| 1823 gclog_or_tty->print_cr("Region ["PTR_FORMAT","PTR_FORMAT"), " | |
| 1824 "claim value = %d, should be %d", | |
| 1825 r->bottom(), r->end(), r->claim_value(), | |
| 1826 _claim_value); | |
| 1827 ++_failures; | |
| 1828 } | |
| 1829 if (!r->isHumongous()) { | |
| 1830 _sh_region = NULL; | |
| 1831 } else if (r->startsHumongous()) { | |
| 1832 _sh_region = r; | |
| 1833 } else if (r->continuesHumongous()) { | |
| 1834 if (r->humongous_start_region() != _sh_region) { | |
| 1835 gclog_or_tty->print_cr("Region ["PTR_FORMAT","PTR_FORMAT"), " | |
| 1836 "HS = "PTR_FORMAT", should be "PTR_FORMAT, | |
| 1837 r->bottom(), r->end(), | |
| 1838 r->humongous_start_region(), | |
| 1839 _sh_region); | |
| 1840 ++_failures; | |
| 342 | 1841 } |
| 1842 } | |
| 355 | 1843 return false; |
| 1844 } | |
| 1845 size_t failures() { | |
| 1846 return _failures; | |
| 1847 } | |
| 1848 }; | |
| 1849 | |
| 1850 bool G1CollectedHeap::check_heap_region_claim_values(jint claim_value) { | |
| 1851 CheckClaimValuesClosure cl(claim_value); | |
| 1852 heap_region_iterate(&cl); | |
| 1853 return cl.failures() == 0; | |
| 1854 } | |
| 1855 #endif // ASSERT | |
| 342 | 1856 |
| 1857 void G1CollectedHeap::collection_set_iterate(HeapRegionClosure* cl) { | |
| 1858 HeapRegion* r = g1_policy()->collection_set(); | |
| 1859 while (r != NULL) { | |
| 1860 HeapRegion* next = r->next_in_collection_set(); | |
| 1861 if (cl->doHeapRegion(r)) { | |
| 1862 cl->incomplete(); | |
| 1863 return; | |
| 1864 } | |
| 1865 r = next; | |
| 1866 } | |
| 1867 } | |
| 1868 | |
| 1869 void G1CollectedHeap::collection_set_iterate_from(HeapRegion* r, | |
| 1870 HeapRegionClosure *cl) { | |
| 1871 assert(r->in_collection_set(), | |
| 1872 "Start region must be a member of the collection set."); | |
| 1873 HeapRegion* cur = r; | |
| 1874 while (cur != NULL) { | |
| 1875 HeapRegion* next = cur->next_in_collection_set(); | |
| 1876 if (cl->doHeapRegion(cur) && false) { | |
| 1877 cl->incomplete(); | |
| 1878 return; | |
| 1879 } | |
| 1880 cur = next; | |
| 1881 } | |
| 1882 cur = g1_policy()->collection_set(); | |
| 1883 while (cur != r) { | |
| 1884 HeapRegion* next = cur->next_in_collection_set(); | |
| 1885 if (cl->doHeapRegion(cur) && false) { | |
| 1886 cl->incomplete(); | |
| 1887 return; | |
| 1888 } | |
| 1889 cur = next; | |
| 1890 } | |
| 1891 } | |
| 1892 | |
| 1893 CompactibleSpace* G1CollectedHeap::first_compactible_space() { | |
| 1894 return _hrs->length() > 0 ? _hrs->at(0) : NULL; | |
| 1895 } | |
| 1896 | |
| 1897 | |
| 1898 Space* G1CollectedHeap::space_containing(const void* addr) const { | |
| 1899 Space* res = heap_region_containing(addr); | |
| 1900 if (res == NULL) | |
| 1901 res = perm_gen()->space_containing(addr); | |
| 1902 return res; | |
| 1903 } | |
| 1904 | |
| 1905 HeapWord* G1CollectedHeap::block_start(const void* addr) const { | |
| 1906 Space* sp = space_containing(addr); | |
| 1907 if (sp != NULL) { | |
| 1908 return sp->block_start(addr); | |
| 1909 } | |
| 1910 return NULL; | |
| 1911 } | |
| 1912 | |
| 1913 size_t G1CollectedHeap::block_size(const HeapWord* addr) const { | |
| 1914 Space* sp = space_containing(addr); | |
| 1915 assert(sp != NULL, "block_size of address outside of heap"); | |
| 1916 return sp->block_size(addr); | |
| 1917 } | |
| 1918 | |
| 1919 bool G1CollectedHeap::block_is_obj(const HeapWord* addr) const { | |
| 1920 Space* sp = space_containing(addr); | |
| 1921 return sp->block_is_obj(addr); | |
| 1922 } | |
| 1923 | |
| 1924 bool G1CollectedHeap::supports_tlab_allocation() const { | |
| 1925 return true; | |
| 1926 } | |
| 1927 | |
| 1928 size_t G1CollectedHeap::tlab_capacity(Thread* ignored) const { | |
| 1929 return HeapRegion::GrainBytes; | |
| 1930 } | |
| 1931 | |
| 1932 size_t G1CollectedHeap::unsafe_max_tlab_alloc(Thread* ignored) const { | |
| 1933 // Return the remaining space in the cur alloc region, but not less than | |
| 1934 // the min TLAB size. | |
| 1935 // Also, no more than half the region size, since we can't allow tlabs to | |
| 1936 // grow big enough to accomodate humongous objects. | |
| 1937 | |
| 1938 // We need to story it locally, since it might change between when we | |
| 1939 // test for NULL and when we use it later. | |
| 1940 ContiguousSpace* cur_alloc_space = _cur_alloc_region; | |
| 1941 if (cur_alloc_space == NULL) { | |
| 1942 return HeapRegion::GrainBytes/2; | |
| 1943 } else { | |
| 1944 return MAX2(MIN2(cur_alloc_space->free(), | |
| 1945 (size_t)(HeapRegion::GrainBytes/2)), | |
| 1946 (size_t)MinTLABSize); | |
| 1947 } | |
| 1948 } | |
| 1949 | |
| 1950 HeapWord* G1CollectedHeap::allocate_new_tlab(size_t size) { | |
| 1951 bool dummy; | |
| 1952 return G1CollectedHeap::mem_allocate(size, false, true, &dummy); | |
| 1953 } | |
| 1954 | |
| 1955 bool G1CollectedHeap::allocs_are_zero_filled() { | |
| 1956 return false; | |
| 1957 } | |
| 1958 | |
| 1959 size_t G1CollectedHeap::large_typearray_limit() { | |
| 1960 // FIXME | |
| 1961 return HeapRegion::GrainBytes/HeapWordSize; | |
| 1962 } | |
| 1963 | |
| 1964 size_t G1CollectedHeap::max_capacity() const { | |
| 1965 return _g1_committed.byte_size(); | |
| 1966 } | |
| 1967 | |
| 1968 jlong G1CollectedHeap::millis_since_last_gc() { | |
| 1969 // assert(false, "NYI"); | |
| 1970 return 0; | |
| 1971 } | |
| 1972 | |
| 1973 | |
| 1974 void G1CollectedHeap::prepare_for_verify() { | |
| 1975 if (SafepointSynchronize::is_at_safepoint() || ! UseTLAB) { | |
| 1976 ensure_parsability(false); | |
| 1977 } | |
| 1978 g1_rem_set()->prepare_for_verify(); | |
| 1979 } | |
| 1980 | |
| 1981 class VerifyLivenessOopClosure: public OopClosure { | |
| 1982 G1CollectedHeap* g1h; | |
| 1983 public: | |
| 1984 VerifyLivenessOopClosure(G1CollectedHeap* _g1h) { | |
| 1985 g1h = _g1h; | |
| 1986 } | |
| 1987 void do_oop(narrowOop *p) { | |
| 1988 guarantee(false, "NYI"); | |
| 1989 } | |
| 1990 void do_oop(oop *p) { | |
| 1991 oop obj = *p; | |
| 1992 assert(obj == NULL || !g1h->is_obj_dead(obj), | |
| 1993 "Dead object referenced by a not dead object"); | |
| 1994 } | |
| 1995 }; | |
| 1996 | |
| 1997 class VerifyObjsInRegionClosure: public ObjectClosure { | |
| 1998 G1CollectedHeap* _g1h; | |
| 1999 size_t _live_bytes; | |
| 2000 HeapRegion *_hr; | |
| 2001 public: | |
| 2002 VerifyObjsInRegionClosure(HeapRegion *hr) : _live_bytes(0), _hr(hr) { | |
| 2003 _g1h = G1CollectedHeap::heap(); | |
| 2004 } | |
| 2005 void do_object(oop o) { | |
| 2006 VerifyLivenessOopClosure isLive(_g1h); | |
| 2007 assert(o != NULL, "Huh?"); | |
| 2008 if (!_g1h->is_obj_dead(o)) { | |
| 2009 o->oop_iterate(&isLive); | |
| 2010 if (!_hr->obj_allocated_since_prev_marking(o)) | |
| 2011 _live_bytes += (o->size() * HeapWordSize); | |
| 2012 } | |
| 2013 } | |
| 2014 size_t live_bytes() { return _live_bytes; } | |
| 2015 }; | |
| 2016 | |
| 2017 class PrintObjsInRegionClosure : public ObjectClosure { | |
| 2018 HeapRegion *_hr; | |
| 2019 G1CollectedHeap *_g1; | |
| 2020 public: | |
| 2021 PrintObjsInRegionClosure(HeapRegion *hr) : _hr(hr) { | |
| 2022 _g1 = G1CollectedHeap::heap(); | |
| 2023 }; | |
| 2024 | |
| 2025 void do_object(oop o) { | |
| 2026 if (o != NULL) { | |
| 2027 HeapWord *start = (HeapWord *) o; | |
| 2028 size_t word_sz = o->size(); | |
| 2029 gclog_or_tty->print("\nPrinting obj "PTR_FORMAT" of size " SIZE_FORMAT | |
| 2030 " isMarkedPrev %d isMarkedNext %d isAllocSince %d\n", | |
| 2031 (void*) o, word_sz, | |
| 2032 _g1->isMarkedPrev(o), | |
| 2033 _g1->isMarkedNext(o), | |
| 2034 _hr->obj_allocated_since_prev_marking(o)); | |
| 2035 HeapWord *end = start + word_sz; | |
| 2036 HeapWord *cur; | |
| 2037 int *val; | |
| 2038 for (cur = start; cur < end; cur++) { | |
| 2039 val = (int *) cur; | |
| 2040 gclog_or_tty->print("\t "PTR_FORMAT":"PTR_FORMAT"\n", val, *val); | |
| 2041 } | |
| 2042 } | |
| 2043 } | |
| 2044 }; | |
| 2045 | |
| 2046 class VerifyRegionClosure: public HeapRegionClosure { | |
| 2047 public: | |
| 2048 bool _allow_dirty; | |
| 390 | 2049 bool _par; |
| 2050 VerifyRegionClosure(bool allow_dirty, bool par = false) | |
| 2051 : _allow_dirty(allow_dirty), _par(par) {} | |
| 342 | 2052 bool doHeapRegion(HeapRegion* r) { |
| 390 | 2053 guarantee(_par || r->claim_value() == HeapRegion::InitialClaimValue, |
| 2054 "Should be unclaimed at verify points."); | |
| 342 | 2055 if (r->isHumongous()) { |
| 2056 if (r->startsHumongous()) { | |
| 2057 // Verify the single H object. | |
| 2058 oop(r->bottom())->verify(); | |
| 2059 size_t word_sz = oop(r->bottom())->size(); | |
| 2060 guarantee(r->top() == r->bottom() + word_sz, | |
| 2061 "Only one object in a humongous region"); | |
| 2062 } | |
| 2063 } else { | |
| 2064 VerifyObjsInRegionClosure not_dead_yet_cl(r); | |
| 2065 r->verify(_allow_dirty); | |
| 2066 r->object_iterate(¬_dead_yet_cl); | |
| 2067 guarantee(r->max_live_bytes() >= not_dead_yet_cl.live_bytes(), | |
| 2068 "More live objects than counted in last complete marking."); | |
| 2069 } | |
| 2070 return false; | |
| 2071 } | |
| 2072 }; | |
| 2073 | |
| 2074 class VerifyRootsClosure: public OopsInGenClosure { | |
| 2075 private: | |
| 2076 G1CollectedHeap* _g1h; | |
| 2077 bool _failures; | |
| 2078 | |
| 2079 public: | |
| 2080 VerifyRootsClosure() : | |
| 2081 _g1h(G1CollectedHeap::heap()), _failures(false) { } | |
| 2082 | |
| 2083 bool failures() { return _failures; } | |
| 2084 | |
| 2085 void do_oop(narrowOop* p) { | |
| 2086 guarantee(false, "NYI"); | |
| 2087 } | |
| 2088 | |
| 2089 void do_oop(oop* p) { | |
| 2090 oop obj = *p; | |
| 2091 if (obj != NULL) { | |
| 2092 if (_g1h->is_obj_dead(obj)) { | |
| 2093 gclog_or_tty->print_cr("Root location "PTR_FORMAT" " | |
| 2094 "points to dead obj "PTR_FORMAT, p, (void*) obj); | |
| 2095 obj->print_on(gclog_or_tty); | |
| 2096 _failures = true; | |
| 2097 } | |
| 2098 } | |
| 2099 } | |
| 2100 }; | |
| 2101 | |
| 390 | 2102 // This is the task used for parallel heap verification. |
| 2103 | |
| 2104 class G1ParVerifyTask: public AbstractGangTask { | |
| 2105 private: | |
| 2106 G1CollectedHeap* _g1h; | |
| 2107 bool _allow_dirty; | |
| 2108 | |
| 2109 public: | |
| 2110 G1ParVerifyTask(G1CollectedHeap* g1h, bool allow_dirty) : | |
| 2111 AbstractGangTask("Parallel verify task"), | |
| 2112 _g1h(g1h), _allow_dirty(allow_dirty) { } | |
| 2113 | |
| 2114 void work(int worker_i) { | |
| 2115 VerifyRegionClosure blk(_allow_dirty, true); | |
| 2116 _g1h->heap_region_par_iterate_chunked(&blk, worker_i, | |
| 2117 HeapRegion::ParVerifyClaimValue); | |
| 2118 } | |
| 2119 }; | |
| 2120 | |
| 342 | 2121 void G1CollectedHeap::verify(bool allow_dirty, bool silent) { |
| 2122 if (SafepointSynchronize::is_at_safepoint() || ! UseTLAB) { | |
| 2123 if (!silent) { gclog_or_tty->print("roots "); } | |
| 2124 VerifyRootsClosure rootsCl; | |
| 2125 process_strong_roots(false, | |
| 2126 SharedHeap::SO_AllClasses, | |
| 2127 &rootsCl, | |
| 2128 &rootsCl); | |
| 2129 rem_set()->invalidate(perm_gen()->used_region(), false); | |
| 2130 if (!silent) { gclog_or_tty->print("heapRegions "); } | |
| 390 | 2131 if (GCParallelVerificationEnabled && ParallelGCThreads > 1) { |
| 2132 assert(check_heap_region_claim_values(HeapRegion::InitialClaimValue), | |
| 2133 "sanity check"); | |
| 2134 | |
| 2135 G1ParVerifyTask task(this, allow_dirty); | |
| 2136 int n_workers = workers()->total_workers(); | |
| 2137 set_par_threads(n_workers); | |
| 2138 workers()->run_task(&task); | |
| 2139 set_par_threads(0); | |
| 2140 | |
| 2141 assert(check_heap_region_claim_values(HeapRegion::ParVerifyClaimValue), | |
| 2142 "sanity check"); | |
| 2143 | |
| 2144 reset_heap_region_claim_values(); | |
| 2145 | |
| 2146 assert(check_heap_region_claim_values(HeapRegion::InitialClaimValue), | |
| 2147 "sanity check"); | |
| 2148 } else { | |
| 2149 VerifyRegionClosure blk(allow_dirty); | |
| 2150 _hrs->iterate(&blk); | |
| 2151 } | |
| 342 | 2152 if (!silent) gclog_or_tty->print("remset "); |
| 2153 rem_set()->verify(); | |
| 2154 guarantee(!rootsCl.failures(), "should not have had failures"); | |
| 2155 } else { | |
| 2156 if (!silent) gclog_or_tty->print("(SKIPPING roots, heapRegions, remset) "); | |
| 2157 } | |
| 2158 } | |
| 2159 | |
| 2160 class PrintRegionClosure: public HeapRegionClosure { | |
| 2161 outputStream* _st; | |
| 2162 public: | |
| 2163 PrintRegionClosure(outputStream* st) : _st(st) {} | |
| 2164 bool doHeapRegion(HeapRegion* r) { | |
| 2165 r->print_on(_st); | |
| 2166 return false; | |
| 2167 } | |
| 2168 }; | |
| 2169 | |
| 2170 void G1CollectedHeap::print() const { print_on(gclog_or_tty); } | |
| 2171 | |
| 2172 void G1CollectedHeap::print_on(outputStream* st) const { | |
| 2173 PrintRegionClosure blk(st); | |
| 2174 _hrs->iterate(&blk); | |
| 2175 } | |
| 2176 | |
| 2177 void G1CollectedHeap::print_gc_threads_on(outputStream* st) const { | |
| 2178 if (ParallelGCThreads > 0) { | |
| 2179 workers()->print_worker_threads(); | |
| 2180 } | |
| 2181 st->print("\"G1 concurrent mark GC Thread\" "); | |
| 2182 _cmThread->print(); | |
| 2183 st->cr(); | |
| 2184 st->print("\"G1 concurrent refinement GC Thread\" "); | |
| 2185 _cg1r->cg1rThread()->print_on(st); | |
| 2186 st->cr(); | |
| 2187 st->print("\"G1 zero-fill GC Thread\" "); | |
| 2188 _czft->print_on(st); | |
| 2189 st->cr(); | |
| 2190 } | |
| 2191 | |
| 2192 void G1CollectedHeap::gc_threads_do(ThreadClosure* tc) const { | |
| 2193 if (ParallelGCThreads > 0) { | |
| 2194 workers()->threads_do(tc); | |
| 2195 } | |
| 2196 tc->do_thread(_cmThread); | |
| 2197 tc->do_thread(_cg1r->cg1rThread()); | |
| 2198 tc->do_thread(_czft); | |
| 2199 } | |
| 2200 | |
| 2201 void G1CollectedHeap::print_tracing_info() const { | |
| 2202 concurrent_g1_refine()->print_final_card_counts(); | |
| 2203 | |
| 2204 // We'll overload this to mean "trace GC pause statistics." | |
| 2205 if (TraceGen0Time || TraceGen1Time) { | |
| 2206 // The "G1CollectorPolicy" is keeping track of these stats, so delegate | |
| 2207 // to that. | |
| 2208 g1_policy()->print_tracing_info(); | |
| 2209 } | |
| 2210 if (SummarizeG1RSStats) { | |
| 2211 g1_rem_set()->print_summary_info(); | |
| 2212 } | |
| 2213 if (SummarizeG1ConcMark) { | |
| 2214 concurrent_mark()->print_summary_info(); | |
| 2215 } | |
| 2216 if (SummarizeG1ZFStats) { | |
| 2217 ConcurrentZFThread::print_summary_info(); | |
| 2218 } | |
| 2219 if (G1SummarizePopularity) { | |
| 2220 print_popularity_summary_info(); | |
| 2221 } | |
| 2222 g1_policy()->print_yg_surv_rate_info(); | |
| 2223 | |
| 2224 GCOverheadReporter::printGCOverhead(); | |
| 2225 | |
| 2226 SpecializationStats::print(); | |
| 2227 } | |
| 2228 | |
| 2229 | |
| 2230 int G1CollectedHeap::addr_to_arena_id(void* addr) const { | |
| 2231 HeapRegion* hr = heap_region_containing(addr); | |
| 2232 if (hr == NULL) { | |
| 2233 return 0; | |
| 2234 } else { | |
| 2235 return 1; | |
| 2236 } | |
| 2237 } | |
| 2238 | |
| 2239 G1CollectedHeap* G1CollectedHeap::heap() { | |
| 2240 assert(_sh->kind() == CollectedHeap::G1CollectedHeap, | |
| 2241 "not a garbage-first heap"); | |
| 2242 return _g1h; | |
| 2243 } | |
| 2244 | |
| 2245 void G1CollectedHeap::gc_prologue(bool full /* Ignored */) { | |
| 2246 if (PrintHeapAtGC){ | |
| 2247 gclog_or_tty->print_cr(" {Heap before GC collections=%d:", total_collections()); | |
| 2248 Universe::print(); | |
| 2249 } | |
| 2250 assert(InlineCacheBuffer::is_empty(), "should have cleaned up ICBuffer"); | |
| 2251 // Call allocation profiler | |
| 2252 AllocationProfiler::iterate_since_last_gc(); | |
| 2253 // Fill TLAB's and such | |
| 2254 ensure_parsability(true); | |
| 2255 } | |
| 2256 | |
| 2257 void G1CollectedHeap::gc_epilogue(bool full /* Ignored */) { | |
| 2258 // FIXME: what is this about? | |
| 2259 // I'm ignoring the "fill_newgen()" call if "alloc_event_enabled" | |
| 2260 // is set. | |
| 2261 COMPILER2_PRESENT(assert(DerivedPointerTable::is_empty(), | |
| 2262 "derived pointer present")); | |
| 2263 | |
| 2264 if (PrintHeapAtGC){ | |
| 2265 gclog_or_tty->print_cr(" Heap after GC collections=%d:", total_collections()); | |
| 2266 Universe::print(); | |
| 2267 gclog_or_tty->print("} "); | |
| 2268 } | |
| 2269 } | |
| 2270 | |
| 2271 void G1CollectedHeap::do_collection_pause() { | |
| 2272 // Read the GC count while holding the Heap_lock | |
| 2273 // we need to do this _before_ wait_for_cleanup_complete(), to | |
| 2274 // ensure that we do not give up the heap lock and potentially | |
| 2275 // pick up the wrong count | |
| 2276 int gc_count_before = SharedHeap::heap()->total_collections(); | |
| 2277 | |
| 2278 // Don't want to do a GC pause while cleanup is being completed! | |
| 2279 wait_for_cleanup_complete(); | |
| 2280 | |
| 2281 g1_policy()->record_stop_world_start(); | |
| 2282 { | |
| 2283 MutexUnlocker mu(Heap_lock); // give up heap lock, execute gets it back | |
| 2284 VM_G1IncCollectionPause op(gc_count_before); | |
| 2285 VMThread::execute(&op); | |
| 2286 } | |
| 2287 } | |
| 2288 | |
| 2289 void | |
| 2290 G1CollectedHeap::doConcurrentMark() { | |
| 2291 if (G1ConcMark) { | |
| 2292 MutexLockerEx x(CGC_lock, Mutex::_no_safepoint_check_flag); | |
| 2293 if (!_cmThread->in_progress()) { | |
| 2294 _cmThread->set_started(); | |
| 2295 CGC_lock->notify(); | |
| 2296 } | |
| 2297 } | |
| 2298 } | |
| 2299 | |
| 2300 class VerifyMarkedObjsClosure: public ObjectClosure { | |
| 2301 G1CollectedHeap* _g1h; | |
| 2302 public: | |
| 2303 VerifyMarkedObjsClosure(G1CollectedHeap* g1h) : _g1h(g1h) {} | |
| 2304 void do_object(oop obj) { | |
| 2305 assert(obj->mark()->is_marked() ? !_g1h->is_obj_dead(obj) : true, | |
| 2306 "markandsweep mark should agree with concurrent deadness"); | |
| 2307 } | |
| 2308 }; | |
| 2309 | |
| 2310 void | |
| 2311 G1CollectedHeap::checkConcurrentMark() { | |
| 2312 VerifyMarkedObjsClosure verifycl(this); | |
| 2313 doConcurrentMark(); | |
| 2314 // MutexLockerEx x(getMarkBitMapLock(), | |
| 2315 // Mutex::_no_safepoint_check_flag); | |
| 2316 object_iterate(&verifycl); | |
| 2317 } | |
| 2318 | |
| 2319 void G1CollectedHeap::do_sync_mark() { | |
| 2320 _cm->checkpointRootsInitial(); | |
| 2321 _cm->markFromRoots(); | |
| 2322 _cm->checkpointRootsFinal(false); | |
| 2323 } | |
| 2324 | |
| 2325 // <NEW PREDICTION> | |
| 2326 | |
| 2327 double G1CollectedHeap::predict_region_elapsed_time_ms(HeapRegion *hr, | |
| 2328 bool young) { | |
| 2329 return _g1_policy->predict_region_elapsed_time_ms(hr, young); | |
| 2330 } | |
| 2331 | |
| 2332 void G1CollectedHeap::check_if_region_is_too_expensive(double | |
| 2333 predicted_time_ms) { | |
| 2334 _g1_policy->check_if_region_is_too_expensive(predicted_time_ms); | |
| 2335 } | |
| 2336 | |
| 2337 size_t G1CollectedHeap::pending_card_num() { | |
| 2338 size_t extra_cards = 0; | |
| 2339 JavaThread *curr = Threads::first(); | |
| 2340 while (curr != NULL) { | |
| 2341 DirtyCardQueue& dcq = curr->dirty_card_queue(); | |
| 2342 extra_cards += dcq.size(); | |
| 2343 curr = curr->next(); | |
| 2344 } | |
| 2345 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 2346 size_t buffer_size = dcqs.buffer_size(); | |
| 2347 size_t buffer_num = dcqs.completed_buffers_num(); | |
| 2348 return buffer_size * buffer_num + extra_cards; | |
| 2349 } | |
| 2350 | |
| 2351 size_t G1CollectedHeap::max_pending_card_num() { | |
| 2352 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 2353 size_t buffer_size = dcqs.buffer_size(); | |
| 2354 size_t buffer_num = dcqs.completed_buffers_num(); | |
| 2355 int thread_num = Threads::number_of_threads(); | |
| 2356 return (buffer_num + thread_num) * buffer_size; | |
| 2357 } | |
| 2358 | |
| 2359 size_t G1CollectedHeap::cards_scanned() { | |
| 2360 HRInto_G1RemSet* g1_rset = (HRInto_G1RemSet*) g1_rem_set(); | |
| 2361 return g1_rset->cardsScanned(); | |
| 2362 } | |
| 2363 | |
| 2364 void | |
| 2365 G1CollectedHeap::setup_surviving_young_words() { | |
| 2366 guarantee( _surviving_young_words == NULL, "pre-condition" ); | |
| 2367 size_t array_length = g1_policy()->young_cset_length(); | |
| 2368 _surviving_young_words = NEW_C_HEAP_ARRAY(size_t, array_length); | |
| 2369 if (_surviving_young_words == NULL) { | |
| 2370 vm_exit_out_of_memory(sizeof(size_t) * array_length, | |
| 2371 "Not enough space for young surv words summary."); | |
| 2372 } | |
| 2373 memset(_surviving_young_words, 0, array_length * sizeof(size_t)); | |
| 2374 for (size_t i = 0; i < array_length; ++i) { | |
| 2375 guarantee( _surviving_young_words[i] == 0, "invariant" ); | |
| 2376 } | |
| 2377 } | |
| 2378 | |
| 2379 void | |
| 2380 G1CollectedHeap::update_surviving_young_words(size_t* surv_young_words) { | |
| 2381 MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag); | |
| 2382 size_t array_length = g1_policy()->young_cset_length(); | |
| 2383 for (size_t i = 0; i < array_length; ++i) | |
| 2384 _surviving_young_words[i] += surv_young_words[i]; | |
| 2385 } | |
| 2386 | |
| 2387 void | |
| 2388 G1CollectedHeap::cleanup_surviving_young_words() { | |
| 2389 guarantee( _surviving_young_words != NULL, "pre-condition" ); | |
| 2390 FREE_C_HEAP_ARRAY(size_t, _surviving_young_words); | |
| 2391 _surviving_young_words = NULL; | |
| 2392 } | |
| 2393 | |
| 2394 // </NEW PREDICTION> | |
| 2395 | |
| 2396 void | |
| 2397 G1CollectedHeap::do_collection_pause_at_safepoint(HeapRegion* popular_region) { | |
| 2398 char verbose_str[128]; | |
| 2399 sprintf(verbose_str, "GC pause "); | |
| 2400 if (popular_region != NULL) | |
| 2401 strcat(verbose_str, "(popular)"); | |
| 2402 else if (g1_policy()->in_young_gc_mode()) { | |
| 2403 if (g1_policy()->full_young_gcs()) | |
| 2404 strcat(verbose_str, "(young)"); | |
| 2405 else | |
| 2406 strcat(verbose_str, "(partial)"); | |
| 2407 } | |
| 2408 bool reset_should_initiate_conc_mark = false; | |
| 2409 if (popular_region != NULL && g1_policy()->should_initiate_conc_mark()) { | |
| 2410 // we currently do not allow an initial mark phase to be piggy-backed | |
| 2411 // on a popular pause | |
| 2412 reset_should_initiate_conc_mark = true; | |
| 2413 g1_policy()->unset_should_initiate_conc_mark(); | |
| 2414 } | |
| 2415 if (g1_policy()->should_initiate_conc_mark()) | |
| 2416 strcat(verbose_str, " (initial-mark)"); | |
| 2417 | |
| 2418 GCCauseSetter x(this, (popular_region == NULL ? | |
| 2419 GCCause::_g1_inc_collection_pause : | |
| 2420 GCCause::_g1_pop_region_collection_pause)); | |
| 2421 | |
| 2422 // if PrintGCDetails is on, we'll print long statistics information | |
| 2423 // in the collector policy code, so let's not print this as the output | |
| 2424 // is messy if we do. | |
| 2425 gclog_or_tty->date_stamp(PrintGC && PrintGCDateStamps); | |
| 2426 TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty); | |
| 2427 TraceTime t(verbose_str, PrintGC && !PrintGCDetails, true, gclog_or_tty); | |
| 2428 | |
| 2429 ResourceMark rm; | |
| 2430 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); | |
| 2431 assert(Thread::current() == VMThread::vm_thread(), "should be in vm thread"); | |
| 2432 guarantee(!is_gc_active(), "collection is not reentrant"); | |
| 2433 assert(regions_accounted_for(), "Region leakage!"); | |
|
353
9bb2c10ac07b
6723570: G1: assertion failure: p == current_top or oop(p)->is_oop(),"p is not a block start" (revisited!)
iveresov
parents:
352
diff
changeset
|
2434 |
|
9bb2c10ac07b
6723570: G1: assertion failure: p == current_top or oop(p)->is_oop(),"p is not a block start" (revisited!)
iveresov
parents:
352
diff
changeset
|
2435 increment_gc_time_stamp(); |
| 342 | 2436 |
| 2437 if (g1_policy()->in_young_gc_mode()) { | |
| 2438 assert(check_young_list_well_formed(), | |
| 2439 "young list should be well formed"); | |
| 2440 } | |
| 2441 | |
| 2442 if (GC_locker::is_active()) { | |
| 2443 return; // GC is disabled (e.g. JNI GetXXXCritical operation) | |
| 2444 } | |
| 2445 | |
| 2446 bool abandoned = false; | |
| 2447 { // Call to jvmpi::post_class_unload_events must occur outside of active GC | |
| 2448 IsGCActiveMark x; | |
| 2449 | |
| 2450 gc_prologue(false); | |
| 2451 increment_total_collections(); | |
| 2452 | |
| 2453 #if G1_REM_SET_LOGGING | |
| 2454 gclog_or_tty->print_cr("\nJust chose CS, heap:"); | |
| 2455 print(); | |
| 2456 #endif | |
| 2457 | |
| 2458 if (VerifyBeforeGC && total_collections() >= VerifyGCStartAt) { | |
| 2459 HandleMark hm; // Discard invalid handles created during verification | |
| 2460 prepare_for_verify(); | |
| 2461 gclog_or_tty->print(" VerifyBeforeGC:"); | |
| 2462 Universe::verify(false); | |
| 2463 } | |
| 2464 | |
| 2465 COMPILER2_PRESENT(DerivedPointerTable::clear()); | |
| 2466 | |
|
453
c96030fff130
6684579: SoftReference processing can be made more efficient
ysr
parents:
393
diff
changeset
|
2467 // We want to turn off ref discovery, if necessary, and turn it back on |
| 342 | 2468 // on again later if we do. |
| 2469 bool was_enabled = ref_processor()->discovery_enabled(); | |
| 2470 if (was_enabled) ref_processor()->disable_discovery(); | |
| 2471 | |
| 2472 // Forget the current alloc region (we might even choose it to be part | |
| 2473 // of the collection set!). | |
| 2474 abandon_cur_alloc_region(); | |
| 2475 | |
| 2476 // The elapsed time induced by the start time below deliberately elides | |
| 2477 // the possible verification above. | |
| 2478 double start_time_sec = os::elapsedTime(); | |
| 2479 GCOverheadReporter::recordSTWStart(start_time_sec); | |
| 2480 size_t start_used_bytes = used(); | |
| 2481 if (!G1ConcMark) { | |
| 2482 do_sync_mark(); | |
| 2483 } | |
| 2484 | |
| 2485 g1_policy()->record_collection_pause_start(start_time_sec, | |
| 2486 start_used_bytes); | |
| 2487 | |
| 2488 #if SCAN_ONLY_VERBOSE | |
| 2489 _young_list->print(); | |
| 2490 #endif // SCAN_ONLY_VERBOSE | |
| 2491 | |
| 2492 if (g1_policy()->should_initiate_conc_mark()) { | |
| 2493 concurrent_mark()->checkpointRootsInitialPre(); | |
| 2494 } | |
| 2495 save_marks(); | |
| 2496 | |
| 2497 // We must do this before any possible evacuation that should propogate | |
| 2498 // marks, including evacuation of popular objects in a popular pause. | |
| 2499 if (mark_in_progress()) { | |
| 2500 double start_time_sec = os::elapsedTime(); | |
| 2501 | |
| 2502 _cm->drainAllSATBBuffers(); | |
| 2503 double finish_mark_ms = (os::elapsedTime() - start_time_sec) * 1000.0; | |
| 2504 g1_policy()->record_satb_drain_time(finish_mark_ms); | |
| 2505 | |
| 2506 } | |
| 2507 // Record the number of elements currently on the mark stack, so we | |
| 2508 // only iterate over these. (Since evacuation may add to the mark | |
| 2509 // stack, doing more exposes race conditions.) If no mark is in | |
| 2510 // progress, this will be zero. | |
| 2511 _cm->set_oops_do_bound(); | |
| 2512 | |
| 2513 assert(regions_accounted_for(), "Region leakage."); | |
| 2514 | |
| 2515 bool abandoned = false; | |
| 2516 | |
| 2517 if (mark_in_progress()) | |
| 2518 concurrent_mark()->newCSet(); | |
| 2519 | |
| 2520 // Now choose the CS. | |
| 2521 if (popular_region == NULL) { | |
| 2522 g1_policy()->choose_collection_set(); | |
| 2523 } else { | |
| 2524 // We may be evacuating a single region (for popularity). | |
| 2525 g1_policy()->record_popular_pause_preamble_start(); | |
| 2526 popularity_pause_preamble(popular_region); | |
| 2527 g1_policy()->record_popular_pause_preamble_end(); | |
| 2528 abandoned = (g1_policy()->collection_set() == NULL); | |
| 2529 // Now we allow more regions to be added (we have to collect | |
| 2530 // all popular regions). | |
| 2531 if (!abandoned) { | |
| 2532 g1_policy()->choose_collection_set(popular_region); | |
| 2533 } | |
| 2534 } | |
| 2535 // We may abandon a pause if we find no region that will fit in the MMU | |
| 2536 // pause. | |
| 2537 abandoned = (g1_policy()->collection_set() == NULL); | |
| 2538 | |
| 2539 // Nothing to do if we were unable to choose a collection set. | |
| 2540 if (!abandoned) { | |
| 2541 #if G1_REM_SET_LOGGING | |
| 2542 gclog_or_tty->print_cr("\nAfter pause, heap:"); | |
| 2543 print(); | |
| 2544 #endif | |
| 2545 | |
| 2546 setup_surviving_young_words(); | |
| 2547 | |
| 2548 // Set up the gc allocation regions. | |
| 2549 get_gc_alloc_regions(); | |
| 2550 | |
| 2551 // Actually do the work... | |
| 2552 evacuate_collection_set(); | |
| 2553 free_collection_set(g1_policy()->collection_set()); | |
| 2554 g1_policy()->clear_collection_set(); | |
| 2555 | |
| 2556 if (popular_region != NULL) { | |
| 2557 // We have to wait until now, because we don't want the region to | |
| 2558 // be rescheduled for pop-evac during RS update. | |
| 2559 popular_region->set_popular_pending(false); | |
| 2560 } | |
| 2561 | |
| 2562 release_gc_alloc_regions(); | |
| 2563 | |
| 2564 cleanup_surviving_young_words(); | |
| 2565 | |
| 2566 if (g1_policy()->in_young_gc_mode()) { | |
| 2567 _young_list->reset_sampled_info(); | |
| 2568 assert(check_young_list_empty(true), | |
| 2569 "young list should be empty"); | |
| 2570 | |
| 2571 #if SCAN_ONLY_VERBOSE | |
| 2572 _young_list->print(); | |
| 2573 #endif // SCAN_ONLY_VERBOSE | |
| 2574 | |
| 2575 _young_list->reset_auxilary_lists(); | |
| 2576 } | |
| 2577 } else { | |
| 2578 COMPILER2_PRESENT(DerivedPointerTable::update_pointers()); | |
| 2579 } | |
| 2580 | |
| 2581 if (evacuation_failed()) { | |
| 2582 _summary_bytes_used = recalculate_used(); | |
| 2583 } else { | |
| 2584 // The "used" of the the collection set have already been subtracted | |
| 2585 // when they were freed. Add in the bytes evacuated. | |
| 2586 _summary_bytes_used += g1_policy()->bytes_in_to_space(); | |
| 2587 } | |
| 2588 | |
| 2589 if (g1_policy()->in_young_gc_mode() && | |
| 2590 g1_policy()->should_initiate_conc_mark()) { | |
| 2591 concurrent_mark()->checkpointRootsInitialPost(); | |
| 2592 set_marking_started(); | |
| 2593 doConcurrentMark(); | |
| 2594 } | |
| 2595 | |
| 2596 #if SCAN_ONLY_VERBOSE | |
| 2597 _young_list->print(); | |
| 2598 #endif // SCAN_ONLY_VERBOSE | |
| 2599 | |
| 2600 double end_time_sec = os::elapsedTime(); | |
| 2601 g1_policy()->record_pause_time((end_time_sec - start_time_sec)*1000.0); | |
| 2602 GCOverheadReporter::recordSTWEnd(end_time_sec); | |
| 2603 g1_policy()->record_collection_pause_end(popular_region != NULL, | |
| 2604 abandoned); | |
| 2605 | |
| 2606 assert(regions_accounted_for(), "Region leakage."); | |
| 2607 | |
| 2608 if (VerifyAfterGC && total_collections() >= VerifyGCStartAt) { | |
| 2609 HandleMark hm; // Discard invalid handles created during verification | |
| 2610 gclog_or_tty->print(" VerifyAfterGC:"); | |
| 2611 Universe::verify(false); | |
| 2612 } | |
| 2613 | |
| 2614 if (was_enabled) ref_processor()->enable_discovery(); | |
| 2615 | |
| 2616 { | |
| 2617 size_t expand_bytes = g1_policy()->expansion_amount(); | |
| 2618 if (expand_bytes > 0) { | |
| 2619 size_t bytes_before = capacity(); | |
| 2620 expand(expand_bytes); | |
| 2621 } | |
| 2622 } | |
| 2623 | |
| 2624 if (mark_in_progress()) | |
| 2625 concurrent_mark()->update_g1_committed(); | |
| 2626 | |
| 2627 gc_epilogue(false); | |
| 2628 } | |
| 2629 | |
| 2630 assert(verify_region_lists(), "Bad region lists."); | |
| 2631 | |
| 2632 if (reset_should_initiate_conc_mark) | |
| 2633 g1_policy()->set_should_initiate_conc_mark(); | |
| 2634 | |
| 2635 if (ExitAfterGCNum > 0 && total_collections() == ExitAfterGCNum) { | |
| 2636 gclog_or_tty->print_cr("Stopping after GC #%d", ExitAfterGCNum); | |
| 2637 print_tracing_info(); | |
| 2638 vm_exit(-1); | |
| 2639 } | |
| 2640 } | |
| 2641 | |
| 2642 void G1CollectedHeap::set_gc_alloc_region(int purpose, HeapRegion* r) { | |
| 2643 assert(purpose >= 0 && purpose < GCAllocPurposeCount, "invalid purpose"); | |
| 2644 HeapWord* original_top = NULL; | |
| 2645 if (r != NULL) | |
| 2646 original_top = r->top(); | |
| 2647 | |
| 2648 // We will want to record the used space in r as being there before gc. | |
| 2649 // One we install it as a GC alloc region it's eligible for allocation. | |
| 2650 // So record it now and use it later. | |
| 2651 size_t r_used = 0; | |
| 2652 if (r != NULL) { | |
| 2653 r_used = r->used(); | |
| 2654 | |
| 2655 if (ParallelGCThreads > 0) { | |
| 2656 // need to take the lock to guard against two threads calling | |
| 2657 // get_gc_alloc_region concurrently (very unlikely but...) | |
| 2658 MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag); | |
| 2659 r->save_marks(); | |
| 2660 } | |
| 2661 } | |
| 2662 HeapRegion* old_alloc_region = _gc_alloc_regions[purpose]; | |
| 2663 _gc_alloc_regions[purpose] = r; | |
| 2664 if (old_alloc_region != NULL) { | |
| 2665 // Replace aliases too. | |
| 2666 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) { | |
| 2667 if (_gc_alloc_regions[ap] == old_alloc_region) { | |
| 2668 _gc_alloc_regions[ap] = r; | |
| 2669 } | |
| 2670 } | |
| 2671 } | |
| 2672 if (r != NULL) { | |
| 2673 push_gc_alloc_region(r); | |
| 2674 if (mark_in_progress() && original_top != r->next_top_at_mark_start()) { | |
| 2675 // We are using a region as a GC alloc region after it has been used | |
| 2676 // as a mutator allocation region during the current marking cycle. | |
| 2677 // The mutator-allocated objects are currently implicitly marked, but | |
| 2678 // when we move hr->next_top_at_mark_start() forward at the the end | |
| 2679 // of the GC pause, they won't be. We therefore mark all objects in | |
| 2680 // the "gap". We do this object-by-object, since marking densely | |
| 2681 // does not currently work right with marking bitmap iteration. This | |
| 2682 // means we rely on TLAB filling at the start of pauses, and no | |
| 2683 // "resuscitation" of filled TLAB's. If we want to do this, we need | |
| 2684 // to fix the marking bitmap iteration. | |
| 2685 HeapWord* curhw = r->next_top_at_mark_start(); | |
| 2686 HeapWord* t = original_top; | |
| 2687 | |
| 2688 while (curhw < t) { | |
| 2689 oop cur = (oop)curhw; | |
| 2690 // We'll assume parallel for generality. This is rare code. | |
| 2691 concurrent_mark()->markAndGrayObjectIfNecessary(cur); // can't we just mark them? | |
| 2692 curhw = curhw + cur->size(); | |
| 2693 } | |
| 2694 assert(curhw == t, "Should have parsed correctly."); | |
| 2695 } | |
| 2696 if (G1PolicyVerbose > 1) { | |
| 2697 gclog_or_tty->print("New alloc region ["PTR_FORMAT", "PTR_FORMAT", " PTR_FORMAT") " | |
| 2698 "for survivors:", r->bottom(), original_top, r->end()); | |
| 2699 r->print(); | |
| 2700 } | |
| 2701 g1_policy()->record_before_bytes(r_used); | |
| 2702 } | |
| 2703 } | |
| 2704 | |
| 2705 void G1CollectedHeap::push_gc_alloc_region(HeapRegion* hr) { | |
| 2706 assert(Thread::current()->is_VM_thread() || | |
| 2707 par_alloc_during_gc_lock()->owned_by_self(), "Precondition"); | |
| 2708 assert(!hr->is_gc_alloc_region() && !hr->in_collection_set(), | |
| 2709 "Precondition."); | |
| 2710 hr->set_is_gc_alloc_region(true); | |
| 2711 hr->set_next_gc_alloc_region(_gc_alloc_region_list); | |
| 2712 _gc_alloc_region_list = hr; | |
| 2713 } | |
| 2714 | |
| 2715 #ifdef G1_DEBUG | |
| 2716 class FindGCAllocRegion: public HeapRegionClosure { | |
| 2717 public: | |
| 2718 bool doHeapRegion(HeapRegion* r) { | |
| 2719 if (r->is_gc_alloc_region()) { | |
| 2720 gclog_or_tty->print_cr("Region %d ["PTR_FORMAT"...] is still a gc_alloc_region.", | |
| 2721 r->hrs_index(), r->bottom()); | |
| 2722 } | |
| 2723 return false; | |
| 2724 } | |
| 2725 }; | |
| 2726 #endif // G1_DEBUG | |
| 2727 | |
| 2728 void G1CollectedHeap::forget_alloc_region_list() { | |
| 2729 assert(Thread::current()->is_VM_thread(), "Precondition"); | |
| 2730 while (_gc_alloc_region_list != NULL) { | |
| 2731 HeapRegion* r = _gc_alloc_region_list; | |
| 2732 assert(r->is_gc_alloc_region(), "Invariant."); | |
| 2733 _gc_alloc_region_list = r->next_gc_alloc_region(); | |
| 2734 r->set_next_gc_alloc_region(NULL); | |
| 2735 r->set_is_gc_alloc_region(false); | |
| 2736 if (r->is_empty()) { | |
| 2737 ++_free_regions; | |
| 2738 } | |
| 2739 } | |
| 2740 #ifdef G1_DEBUG | |
| 2741 FindGCAllocRegion fa; | |
| 2742 heap_region_iterate(&fa); | |
| 2743 #endif // G1_DEBUG | |
| 2744 } | |
| 2745 | |
| 2746 | |
| 2747 bool G1CollectedHeap::check_gc_alloc_regions() { | |
| 2748 // TODO: allocation regions check | |
| 2749 return true; | |
| 2750 } | |
| 2751 | |
| 2752 void G1CollectedHeap::get_gc_alloc_regions() { | |
| 2753 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) { | |
| 2754 // Create new GC alloc regions. | |
| 2755 HeapRegion* alloc_region = _gc_alloc_regions[ap]; | |
| 2756 // Clear this alloc region, so that in case it turns out to be | |
| 2757 // unacceptable, we end up with no allocation region, rather than a bad | |
| 2758 // one. | |
| 2759 _gc_alloc_regions[ap] = NULL; | |
| 2760 if (alloc_region == NULL || alloc_region->in_collection_set()) { | |
| 2761 // Can't re-use old one. Allocate a new one. | |
| 2762 alloc_region = newAllocRegionWithExpansion(ap, 0); | |
| 2763 } | |
| 2764 if (alloc_region != NULL) { | |
| 2765 set_gc_alloc_region(ap, alloc_region); | |
| 2766 } | |
| 2767 } | |
| 2768 // Set alternative regions for allocation purposes that have reached | |
| 2769 // thier limit. | |
| 2770 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) { | |
| 2771 GCAllocPurpose alt_purpose = g1_policy()->alternative_purpose(ap); | |
| 2772 if (_gc_alloc_regions[ap] == NULL && alt_purpose != ap) { | |
| 2773 _gc_alloc_regions[ap] = _gc_alloc_regions[alt_purpose]; | |
| 2774 } | |
| 2775 } | |
| 2776 assert(check_gc_alloc_regions(), "alloc regions messed up"); | |
| 2777 } | |
| 2778 | |
| 2779 void G1CollectedHeap::release_gc_alloc_regions() { | |
| 2780 // We keep a separate list of all regions that have been alloc regions in | |
| 2781 // the current collection pause. Forget that now. | |
| 2782 forget_alloc_region_list(); | |
| 2783 | |
| 2784 // The current alloc regions contain objs that have survived | |
| 2785 // collection. Make them no longer GC alloc regions. | |
| 2786 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) { | |
| 2787 HeapRegion* r = _gc_alloc_regions[ap]; | |
| 2788 if (r != NULL && r->is_empty()) { | |
| 2789 { | |
| 2790 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 2791 r->set_zero_fill_complete(); | |
| 2792 put_free_region_on_list_locked(r); | |
| 2793 } | |
| 2794 } | |
| 2795 // set_gc_alloc_region will also NULLify all aliases to the region | |
| 2796 set_gc_alloc_region(ap, NULL); | |
| 2797 _gc_alloc_region_counts[ap] = 0; | |
| 2798 } | |
| 2799 } | |
| 2800 | |
| 2801 void G1CollectedHeap::init_for_evac_failure(OopsInHeapRegionClosure* cl) { | |
| 2802 _drain_in_progress = false; | |
| 2803 set_evac_failure_closure(cl); | |
| 2804 _evac_failure_scan_stack = new (ResourceObj::C_HEAP) GrowableArray<oop>(40, true); | |
| 2805 } | |
| 2806 | |
| 2807 void G1CollectedHeap::finalize_for_evac_failure() { | |
| 2808 assert(_evac_failure_scan_stack != NULL && | |
| 2809 _evac_failure_scan_stack->length() == 0, | |
| 2810 "Postcondition"); | |
| 2811 assert(!_drain_in_progress, "Postcondition"); | |
| 2812 // Don't have to delete, since the scan stack is a resource object. | |
| 2813 _evac_failure_scan_stack = NULL; | |
| 2814 } | |
| 2815 | |
| 2816 | |
| 2817 | |
| 2818 // *** Sequential G1 Evacuation | |
| 2819 | |
| 2820 HeapWord* G1CollectedHeap::allocate_during_gc(GCAllocPurpose purpose, size_t word_size) { | |
| 2821 HeapRegion* alloc_region = _gc_alloc_regions[purpose]; | |
| 2822 // let the caller handle alloc failure | |
| 2823 if (alloc_region == NULL) return NULL; | |
| 2824 assert(isHumongous(word_size) || !alloc_region->isHumongous(), | |
| 2825 "Either the object is humongous or the region isn't"); | |
| 2826 HeapWord* block = alloc_region->allocate(word_size); | |
| 2827 if (block == NULL) { | |
| 2828 block = allocate_during_gc_slow(purpose, alloc_region, false, word_size); | |
| 2829 } | |
| 2830 return block; | |
| 2831 } | |
| 2832 | |
| 2833 class G1IsAliveClosure: public BoolObjectClosure { | |
| 2834 G1CollectedHeap* _g1; | |
| 2835 public: | |
| 2836 G1IsAliveClosure(G1CollectedHeap* g1) : _g1(g1) {} | |
| 2837 void do_object(oop p) { assert(false, "Do not call."); } | |
| 2838 bool do_object_b(oop p) { | |
| 2839 // It is reachable if it is outside the collection set, or is inside | |
| 2840 // and forwarded. | |
| 2841 | |
| 2842 #ifdef G1_DEBUG | |
| 2843 gclog_or_tty->print_cr("is alive "PTR_FORMAT" in CS %d forwarded %d overall %d", | |
| 2844 (void*) p, _g1->obj_in_cs(p), p->is_forwarded(), | |
| 2845 !_g1->obj_in_cs(p) || p->is_forwarded()); | |
| 2846 #endif // G1_DEBUG | |
| 2847 | |
| 2848 return !_g1->obj_in_cs(p) || p->is_forwarded(); | |
| 2849 } | |
| 2850 }; | |
| 2851 | |
| 2852 class G1KeepAliveClosure: public OopClosure { | |
| 2853 G1CollectedHeap* _g1; | |
| 2854 public: | |
| 2855 G1KeepAliveClosure(G1CollectedHeap* g1) : _g1(g1) {} | |
| 2856 void do_oop(narrowOop* p) { | |
| 2857 guarantee(false, "NYI"); | |
| 2858 } | |
| 2859 void do_oop(oop* p) { | |
| 2860 oop obj = *p; | |
| 2861 #ifdef G1_DEBUG | |
| 2862 if (PrintGC && Verbose) { | |
| 2863 gclog_or_tty->print_cr("keep alive *"PTR_FORMAT" = "PTR_FORMAT" "PTR_FORMAT, | |
| 2864 p, (void*) obj, (void*) *p); | |
| 2865 } | |
| 2866 #endif // G1_DEBUG | |
| 2867 | |
| 2868 if (_g1->obj_in_cs(obj)) { | |
| 2869 assert( obj->is_forwarded(), "invariant" ); | |
| 2870 *p = obj->forwardee(); | |
| 2871 | |
| 2872 #ifdef G1_DEBUG | |
| 2873 gclog_or_tty->print_cr(" in CSet: moved "PTR_FORMAT" -> "PTR_FORMAT, | |
| 2874 (void*) obj, (void*) *p); | |
| 2875 #endif // G1_DEBUG | |
| 2876 } | |
| 2877 } | |
| 2878 }; | |
| 2879 | |
| 2880 class RecreateRSetEntriesClosure: public OopClosure { | |
| 2881 private: | |
| 2882 G1CollectedHeap* _g1; | |
| 2883 G1RemSet* _g1_rem_set; | |
| 2884 HeapRegion* _from; | |
| 2885 public: | |
| 2886 RecreateRSetEntriesClosure(G1CollectedHeap* g1, HeapRegion* from) : | |
| 2887 _g1(g1), _g1_rem_set(g1->g1_rem_set()), _from(from) | |
| 2888 {} | |
| 2889 | |
| 2890 void do_oop(narrowOop* p) { | |
| 2891 guarantee(false, "NYI"); | |
| 2892 } | |
| 2893 void do_oop(oop* p) { | |
| 2894 assert(_from->is_in_reserved(p), "paranoia"); | |
| 2895 if (*p != NULL) { | |
| 2896 _g1_rem_set->write_ref(_from, p); | |
| 2897 } | |
| 2898 } | |
| 2899 }; | |
| 2900 | |
| 2901 class RemoveSelfPointerClosure: public ObjectClosure { | |
| 2902 private: | |
| 2903 G1CollectedHeap* _g1; | |
| 2904 ConcurrentMark* _cm; | |
| 2905 HeapRegion* _hr; | |
| 2906 size_t _prev_marked_bytes; | |
| 2907 size_t _next_marked_bytes; | |
| 2908 public: | |
| 2909 RemoveSelfPointerClosure(G1CollectedHeap* g1, HeapRegion* hr) : | |
| 2910 _g1(g1), _cm(_g1->concurrent_mark()), _hr(hr), | |
| 2911 _prev_marked_bytes(0), _next_marked_bytes(0) | |
| 2912 {} | |
| 2913 | |
| 2914 size_t prev_marked_bytes() { return _prev_marked_bytes; } | |
| 2915 size_t next_marked_bytes() { return _next_marked_bytes; } | |
| 2916 | |
|
352
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2917 // The original idea here was to coalesce evacuated and dead objects. |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2918 // However that caused complications with the block offset table (BOT). |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2919 // In particular if there were two TLABs, one of them partially refined. |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2920 // |----- TLAB_1--------|----TLAB_2-~~~(partially refined part)~~~| |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2921 // The BOT entries of the unrefined part of TLAB_2 point to the start |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2922 // of TLAB_2. If the last object of the TLAB_1 and the first object |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2923 // of TLAB_2 are coalesced, then the cards of the unrefined part |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2924 // would point into middle of the filler object. |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2925 // |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2926 // The current approach is to not coalesce and leave the BOT contents intact. |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2927 void do_object(oop obj) { |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2928 if (obj->is_forwarded() && obj->forwardee() == obj) { |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2929 // The object failed to move. |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2930 assert(!_g1->is_obj_dead(obj), "We should not be preserving dead objs."); |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2931 _cm->markPrev(obj); |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2932 assert(_cm->isPrevMarked(obj), "Should be marked!"); |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2933 _prev_marked_bytes += (obj->size() * HeapWordSize); |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2934 if (_g1->mark_in_progress() && !_g1->is_obj_ill(obj)) { |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2935 _cm->markAndGrayObjectIfNecessary(obj); |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2936 } |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2937 obj->set_mark(markOopDesc::prototype()); |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2938 // While we were processing RSet buffers during the |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2939 // collection, we actually didn't scan any cards on the |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2940 // collection set, since we didn't want to update remebered |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2941 // sets with entries that point into the collection set, given |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2942 // that live objects fromthe collection set are about to move |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2943 // and such entries will be stale very soon. This change also |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2944 // dealt with a reliability issue which involved scanning a |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2945 // card in the collection set and coming across an array that |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2946 // was being chunked and looking malformed. The problem is |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2947 // that, if evacuation fails, we might have remembered set |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2948 // entries missing given that we skipped cards on the |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2949 // collection set. So, we'll recreate such entries now. |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2950 RecreateRSetEntriesClosure cl(_g1, _hr); |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2951 obj->oop_iterate(&cl); |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2952 assert(_cm->isPrevMarked(obj), "Should be marked!"); |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2953 } else { |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2954 // The object has been either evacuated or is dead. Fill it with a |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2955 // dummy object. |
|
e0c09f7ec5c4
6702387: G1: assertion failure: assert(p == current_top || oop(p)->is_oop(),"p is not a block start")
iveresov
parents:
342
diff
changeset
|
2956 MemRegion mr((HeapWord*)obj, obj->size()); |
|
481
7d7a7c599c17
6578152: fill_region_with_object has usability and safety issues
jcoomes
parents:
457
diff
changeset
|
2957 CollectedHeap::fill_with_object(mr); |
| 342 | 2958 _cm->clearRangeBothMaps(mr); |
| 2959 } | |
| 2960 } | |
| 2961 }; | |
| 2962 | |
| 2963 void G1CollectedHeap::remove_self_forwarding_pointers() { | |
| 2964 HeapRegion* cur = g1_policy()->collection_set(); | |
| 2965 | |
| 2966 while (cur != NULL) { | |
| 2967 assert(g1_policy()->assertMarkedBytesDataOK(), "Should be!"); | |
| 2968 | |
| 2969 if (cur->evacuation_failed()) { | |
| 2970 RemoveSelfPointerClosure rspc(_g1h, cur); | |
| 2971 assert(cur->in_collection_set(), "bad CS"); | |
| 2972 cur->object_iterate(&rspc); | |
| 2973 | |
| 2974 // A number of manipulations to make the TAMS be the current top, | |
| 2975 // and the marked bytes be the ones observed in the iteration. | |
| 2976 if (_g1h->concurrent_mark()->at_least_one_mark_complete()) { | |
| 2977 // The comments below are the postconditions achieved by the | |
| 2978 // calls. Note especially the last such condition, which says that | |
| 2979 // the count of marked bytes has been properly restored. | |
| 2980 cur->note_start_of_marking(false); | |
| 2981 // _next_top_at_mark_start == top, _next_marked_bytes == 0 | |
| 2982 cur->add_to_marked_bytes(rspc.prev_marked_bytes()); | |
| 2983 // _next_marked_bytes == prev_marked_bytes. | |
| 2984 cur->note_end_of_marking(); | |
| 2985 // _prev_top_at_mark_start == top(), | |
| 2986 // _prev_marked_bytes == prev_marked_bytes | |
| 2987 } | |
| 2988 // If there is no mark in progress, we modified the _next variables | |
| 2989 // above needlessly, but harmlessly. | |
| 2990 if (_g1h->mark_in_progress()) { | |
| 2991 cur->note_start_of_marking(false); | |
| 2992 // _next_top_at_mark_start == top, _next_marked_bytes == 0 | |
| 2993 // _next_marked_bytes == next_marked_bytes. | |
| 2994 } | |
| 2995 | |
| 2996 // Now make sure the region has the right index in the sorted array. | |
| 2997 g1_policy()->note_change_in_marked_bytes(cur); | |
| 2998 } | |
| 2999 cur = cur->next_in_collection_set(); | |
| 3000 } | |
| 3001 assert(g1_policy()->assertMarkedBytesDataOK(), "Should be!"); | |
| 3002 | |
| 3003 // Now restore saved marks, if any. | |
| 3004 if (_objs_with_preserved_marks != NULL) { | |
| 3005 assert(_preserved_marks_of_objs != NULL, "Both or none."); | |
| 3006 assert(_objs_with_preserved_marks->length() == | |
| 3007 _preserved_marks_of_objs->length(), "Both or none."); | |
| 3008 guarantee(_objs_with_preserved_marks->length() == | |
| 3009 _preserved_marks_of_objs->length(), "Both or none."); | |
| 3010 for (int i = 0; i < _objs_with_preserved_marks->length(); i++) { | |
| 3011 oop obj = _objs_with_preserved_marks->at(i); | |
| 3012 markOop m = _preserved_marks_of_objs->at(i); | |
| 3013 obj->set_mark(m); | |
| 3014 } | |
| 3015 // Delete the preserved marks growable arrays (allocated on the C heap). | |
| 3016 delete _objs_with_preserved_marks; | |
| 3017 delete _preserved_marks_of_objs; | |
| 3018 _objs_with_preserved_marks = NULL; | |
| 3019 _preserved_marks_of_objs = NULL; | |
| 3020 } | |
| 3021 } | |
| 3022 | |
| 3023 void G1CollectedHeap::push_on_evac_failure_scan_stack(oop obj) { | |
| 3024 _evac_failure_scan_stack->push(obj); | |
| 3025 } | |
| 3026 | |
| 3027 void G1CollectedHeap::drain_evac_failure_scan_stack() { | |
| 3028 assert(_evac_failure_scan_stack != NULL, "precondition"); | |
| 3029 | |
| 3030 while (_evac_failure_scan_stack->length() > 0) { | |
| 3031 oop obj = _evac_failure_scan_stack->pop(); | |
| 3032 _evac_failure_closure->set_region(heap_region_containing(obj)); | |
| 3033 obj->oop_iterate_backwards(_evac_failure_closure); | |
| 3034 } | |
| 3035 } | |
| 3036 | |
| 3037 void G1CollectedHeap::handle_evacuation_failure(oop old) { | |
| 3038 markOop m = old->mark(); | |
| 3039 // forward to self | |
| 3040 assert(!old->is_forwarded(), "precondition"); | |
| 3041 | |
| 3042 old->forward_to(old); | |
| 3043 handle_evacuation_failure_common(old, m); | |
| 3044 } | |
| 3045 | |
| 3046 oop | |
| 3047 G1CollectedHeap::handle_evacuation_failure_par(OopsInHeapRegionClosure* cl, | |
| 3048 oop old) { | |
| 3049 markOop m = old->mark(); | |
| 3050 oop forward_ptr = old->forward_to_atomic(old); | |
| 3051 if (forward_ptr == NULL) { | |
| 3052 // Forward-to-self succeeded. | |
| 3053 if (_evac_failure_closure != cl) { | |
| 3054 MutexLockerEx x(EvacFailureStack_lock, Mutex::_no_safepoint_check_flag); | |
| 3055 assert(!_drain_in_progress, | |
| 3056 "Should only be true while someone holds the lock."); | |
| 3057 // Set the global evac-failure closure to the current thread's. | |
| 3058 assert(_evac_failure_closure == NULL, "Or locking has failed."); | |
| 3059 set_evac_failure_closure(cl); | |
| 3060 // Now do the common part. | |
| 3061 handle_evacuation_failure_common(old, m); | |
| 3062 // Reset to NULL. | |
| 3063 set_evac_failure_closure(NULL); | |
| 3064 } else { | |
| 3065 // The lock is already held, and this is recursive. | |
| 3066 assert(_drain_in_progress, "This should only be the recursive case."); | |
| 3067 handle_evacuation_failure_common(old, m); | |
| 3068 } | |
| 3069 return old; | |
| 3070 } else { | |
| 3071 // Someone else had a place to copy it. | |
| 3072 return forward_ptr; | |
| 3073 } | |
| 3074 } | |
| 3075 | |
| 3076 void G1CollectedHeap::handle_evacuation_failure_common(oop old, markOop m) { | |
| 3077 set_evacuation_failed(true); | |
| 3078 | |
| 3079 preserve_mark_if_necessary(old, m); | |
| 3080 | |
| 3081 HeapRegion* r = heap_region_containing(old); | |
| 3082 if (!r->evacuation_failed()) { | |
| 3083 r->set_evacuation_failed(true); | |
| 3084 if (G1TraceRegions) { | |
| 3085 gclog_or_tty->print("evacuation failed in heap region "PTR_FORMAT" " | |
| 3086 "["PTR_FORMAT","PTR_FORMAT")\n", | |
| 3087 r, r->bottom(), r->end()); | |
| 3088 } | |
| 3089 } | |
| 3090 | |
| 3091 push_on_evac_failure_scan_stack(old); | |
| 3092 | |
| 3093 if (!_drain_in_progress) { | |
| 3094 // prevent recursion in copy_to_survivor_space() | |
| 3095 _drain_in_progress = true; | |
| 3096 drain_evac_failure_scan_stack(); | |
| 3097 _drain_in_progress = false; | |
| 3098 } | |
| 3099 } | |
| 3100 | |
| 3101 void G1CollectedHeap::preserve_mark_if_necessary(oop obj, markOop m) { | |
| 3102 if (m != markOopDesc::prototype()) { | |
| 3103 if (_objs_with_preserved_marks == NULL) { | |
| 3104 assert(_preserved_marks_of_objs == NULL, "Both or none."); | |
| 3105 _objs_with_preserved_marks = | |
| 3106 new (ResourceObj::C_HEAP) GrowableArray<oop>(40, true); | |
| 3107 _preserved_marks_of_objs = | |
| 3108 new (ResourceObj::C_HEAP) GrowableArray<markOop>(40, true); | |
| 3109 } | |
| 3110 _objs_with_preserved_marks->push(obj); | |
| 3111 _preserved_marks_of_objs->push(m); | |
| 3112 } | |
| 3113 } | |
| 3114 | |
| 3115 // *** Parallel G1 Evacuation | |
| 3116 | |
| 3117 HeapWord* G1CollectedHeap::par_allocate_during_gc(GCAllocPurpose purpose, | |
| 3118 size_t word_size) { | |
| 3119 HeapRegion* alloc_region = _gc_alloc_regions[purpose]; | |
| 3120 // let the caller handle alloc failure | |
| 3121 if (alloc_region == NULL) return NULL; | |
| 3122 | |
| 3123 HeapWord* block = alloc_region->par_allocate(word_size); | |
| 3124 if (block == NULL) { | |
| 3125 MutexLockerEx x(par_alloc_during_gc_lock(), | |
| 3126 Mutex::_no_safepoint_check_flag); | |
| 3127 block = allocate_during_gc_slow(purpose, alloc_region, true, word_size); | |
| 3128 } | |
| 3129 return block; | |
| 3130 } | |
| 3131 | |
| 3132 HeapWord* | |
| 3133 G1CollectedHeap::allocate_during_gc_slow(GCAllocPurpose purpose, | |
| 3134 HeapRegion* alloc_region, | |
| 3135 bool par, | |
| 3136 size_t word_size) { | |
| 3137 HeapWord* block = NULL; | |
| 3138 // In the parallel case, a previous thread to obtain the lock may have | |
| 3139 // already assigned a new gc_alloc_region. | |
| 3140 if (alloc_region != _gc_alloc_regions[purpose]) { | |
| 3141 assert(par, "But should only happen in parallel case."); | |
| 3142 alloc_region = _gc_alloc_regions[purpose]; | |
| 3143 if (alloc_region == NULL) return NULL; | |
| 3144 block = alloc_region->par_allocate(word_size); | |
| 3145 if (block != NULL) return block; | |
| 3146 // Otherwise, continue; this new region is empty, too. | |
| 3147 } | |
| 3148 assert(alloc_region != NULL, "We better have an allocation region"); | |
| 3149 // Another thread might have obtained alloc_region for the given | |
| 3150 // purpose, and might be attempting to allocate in it, and might | |
| 3151 // succeed. Therefore, we can't do the "finalization" stuff on the | |
| 3152 // region below until we're sure the last allocation has happened. | |
| 3153 // We ensure this by allocating the remaining space with a garbage | |
| 3154 // object. | |
| 3155 if (par) par_allocate_remaining_space(alloc_region); | |
| 3156 // Now we can do the post-GC stuff on the region. | |
| 3157 alloc_region->note_end_of_copying(); | |
| 3158 g1_policy()->record_after_bytes(alloc_region->used()); | |
| 3159 | |
| 3160 if (_gc_alloc_region_counts[purpose] >= g1_policy()->max_regions(purpose)) { | |
| 3161 // Cannot allocate more regions for the given purpose. | |
| 3162 GCAllocPurpose alt_purpose = g1_policy()->alternative_purpose(purpose); | |
| 3163 // Is there an alternative? | |
| 3164 if (purpose != alt_purpose) { | |
| 3165 HeapRegion* alt_region = _gc_alloc_regions[alt_purpose]; | |
| 3166 // Has not the alternative region been aliased? | |
| 3167 if (alloc_region != alt_region) { | |
| 3168 // Try to allocate in the alternative region. | |
| 3169 if (par) { | |
| 3170 block = alt_region->par_allocate(word_size); | |
| 3171 } else { | |
| 3172 block = alt_region->allocate(word_size); | |
| 3173 } | |
| 3174 // Make an alias. | |
| 3175 _gc_alloc_regions[purpose] = _gc_alloc_regions[alt_purpose]; | |
| 3176 } | |
| 3177 if (block != NULL) { | |
| 3178 return block; | |
| 3179 } | |
| 3180 // Both the allocation region and the alternative one are full | |
| 3181 // and aliased, replace them with a new allocation region. | |
| 3182 purpose = alt_purpose; | |
| 3183 } else { | |
| 3184 set_gc_alloc_region(purpose, NULL); | |
| 3185 return NULL; | |
| 3186 } | |
| 3187 } | |
| 3188 | |
| 3189 // Now allocate a new region for allocation. | |
| 3190 alloc_region = newAllocRegionWithExpansion(purpose, word_size, false /*zero_filled*/); | |
| 3191 | |
| 3192 // let the caller handle alloc failure | |
| 3193 if (alloc_region != NULL) { | |
| 3194 | |
| 3195 assert(check_gc_alloc_regions(), "alloc regions messed up"); | |
| 3196 assert(alloc_region->saved_mark_at_top(), | |
| 3197 "Mark should have been saved already."); | |
| 3198 // We used to assert that the region was zero-filled here, but no | |
| 3199 // longer. | |
| 3200 | |
| 3201 // This must be done last: once it's installed, other regions may | |
| 3202 // allocate in it (without holding the lock.) | |
| 3203 set_gc_alloc_region(purpose, alloc_region); | |
| 3204 | |
| 3205 if (par) { | |
| 3206 block = alloc_region->par_allocate(word_size); | |
| 3207 } else { | |
| 3208 block = alloc_region->allocate(word_size); | |
| 3209 } | |
| 3210 // Caller handles alloc failure. | |
| 3211 } else { | |
| 3212 // This sets other apis using the same old alloc region to NULL, also. | |
| 3213 set_gc_alloc_region(purpose, NULL); | |
| 3214 } | |
| 3215 return block; // May be NULL. | |
| 3216 } | |
| 3217 | |
| 3218 void G1CollectedHeap::par_allocate_remaining_space(HeapRegion* r) { | |
| 3219 HeapWord* block = NULL; | |
| 3220 size_t free_words; | |
| 3221 do { | |
| 3222 free_words = r->free()/HeapWordSize; | |
| 3223 // If there's too little space, no one can allocate, so we're done. | |
| 3224 if (free_words < (size_t)oopDesc::header_size()) return; | |
| 3225 // Otherwise, try to claim it. | |
| 3226 block = r->par_allocate(free_words); | |
| 3227 } while (block == NULL); | |
|
481
7d7a7c599c17
6578152: fill_region_with_object has usability and safety issues
jcoomes
parents:
457
diff
changeset
|
3228 fill_with_object(block, free_words); |
| 342 | 3229 } |
| 3230 | |
| 3231 #define use_local_bitmaps 1 | |
| 3232 #define verify_local_bitmaps 0 | |
| 3233 | |
| 3234 #ifndef PRODUCT | |
| 3235 | |
| 3236 class GCLabBitMap; | |
| 3237 class GCLabBitMapClosure: public BitMapClosure { | |
| 3238 private: | |
| 3239 ConcurrentMark* _cm; | |
| 3240 GCLabBitMap* _bitmap; | |
| 3241 | |
| 3242 public: | |
| 3243 GCLabBitMapClosure(ConcurrentMark* cm, | |
| 3244 GCLabBitMap* bitmap) { | |
| 3245 _cm = cm; | |
| 3246 _bitmap = bitmap; | |
| 3247 } | |
| 3248 | |
| 3249 virtual bool do_bit(size_t offset); | |
| 3250 }; | |
| 3251 | |
| 3252 #endif // PRODUCT | |
| 3253 | |
| 3254 #define oop_buffer_length 256 | |
| 3255 | |
| 3256 class GCLabBitMap: public BitMap { | |
| 3257 private: | |
| 3258 ConcurrentMark* _cm; | |
| 3259 | |
| 3260 int _shifter; | |
| 3261 size_t _bitmap_word_covers_words; | |
| 3262 | |
| 3263 // beginning of the heap | |
| 3264 HeapWord* _heap_start; | |
| 3265 | |
| 3266 // this is the actual start of the GCLab | |
| 3267 HeapWord* _real_start_word; | |
| 3268 | |
| 3269 // this is the actual end of the GCLab | |
| 3270 HeapWord* _real_end_word; | |
| 3271 | |
| 3272 // this is the first word, possibly located before the actual start | |
| 3273 // of the GCLab, that corresponds to the first bit of the bitmap | |
| 3274 HeapWord* _start_word; | |
| 3275 | |
| 3276 // size of a GCLab in words | |
| 3277 size_t _gclab_word_size; | |
| 3278 | |
| 3279 static int shifter() { | |
| 3280 return MinObjAlignment - 1; | |
| 3281 } | |
| 3282 | |
| 3283 // how many heap words does a single bitmap word corresponds to? | |
| 3284 static size_t bitmap_word_covers_words() { | |
| 3285 return BitsPerWord << shifter(); | |
| 3286 } | |
| 3287 | |
| 3288 static size_t gclab_word_size() { | |
| 3289 return ParallelGCG1AllocBufferSize / HeapWordSize; | |
| 3290 } | |
| 3291 | |
| 3292 static size_t bitmap_size_in_bits() { | |
| 3293 size_t bits_in_bitmap = gclab_word_size() >> shifter(); | |
| 3294 // We are going to ensure that the beginning of a word in this | |
| 3295 // bitmap also corresponds to the beginning of a word in the | |
| 3296 // global marking bitmap. To handle the case where a GCLab | |
| 3297 // starts from the middle of the bitmap, we need to add enough | |
| 3298 // space (i.e. up to a bitmap word) to ensure that we have | |
| 3299 // enough bits in the bitmap. | |
| 3300 return bits_in_bitmap + BitsPerWord - 1; | |
| 3301 } | |
| 3302 public: | |
| 3303 GCLabBitMap(HeapWord* heap_start) | |
| 3304 : BitMap(bitmap_size_in_bits()), | |
| 3305 _cm(G1CollectedHeap::heap()->concurrent_mark()), | |
| 3306 _shifter(shifter()), | |
| 3307 _bitmap_word_covers_words(bitmap_word_covers_words()), | |
| 3308 _heap_start(heap_start), | |
| 3309 _gclab_word_size(gclab_word_size()), | |
| 3310 _real_start_word(NULL), | |
| 3311 _real_end_word(NULL), | |
| 3312 _start_word(NULL) | |
| 3313 { | |
| 3314 guarantee( size_in_words() >= bitmap_size_in_words(), | |
| 3315 "just making sure"); | |
| 3316 } | |
| 3317 | |
| 3318 inline unsigned heapWordToOffset(HeapWord* addr) { | |
| 3319 unsigned offset = (unsigned) pointer_delta(addr, _start_word) >> _shifter; | |
| 3320 assert(offset < size(), "offset should be within bounds"); | |
| 3321 return offset; | |
| 3322 } | |
| 3323 | |
| 3324 inline HeapWord* offsetToHeapWord(size_t offset) { | |
| 3325 HeapWord* addr = _start_word + (offset << _shifter); | |
| 3326 assert(_real_start_word <= addr && addr < _real_end_word, "invariant"); | |
| 3327 return addr; | |
| 3328 } | |
| 3329 | |
| 3330 bool fields_well_formed() { | |
| 3331 bool ret1 = (_real_start_word == NULL) && | |
| 3332 (_real_end_word == NULL) && | |
| 3333 (_start_word == NULL); | |
| 3334 if (ret1) | |
| 3335 return true; | |
| 3336 | |
| 3337 bool ret2 = _real_start_word >= _start_word && | |
| 3338 _start_word < _real_end_word && | |
| 3339 (_real_start_word + _gclab_word_size) == _real_end_word && | |
| 3340 (_start_word + _gclab_word_size + _bitmap_word_covers_words) | |
| 3341 > _real_end_word; | |
| 3342 return ret2; | |
| 3343 } | |
| 3344 | |
| 3345 inline bool mark(HeapWord* addr) { | |
| 3346 guarantee(use_local_bitmaps, "invariant"); | |
| 3347 assert(fields_well_formed(), "invariant"); | |
| 3348 | |
| 3349 if (addr >= _real_start_word && addr < _real_end_word) { | |
| 3350 assert(!isMarked(addr), "should not have already been marked"); | |
| 3351 | |
| 3352 // first mark it on the bitmap | |
| 3353 at_put(heapWordToOffset(addr), true); | |
| 3354 | |
| 3355 return true; | |
| 3356 } else { | |
| 3357 return false; | |
| 3358 } | |
| 3359 } | |
| 3360 | |
| 3361 inline bool isMarked(HeapWord* addr) { | |
| 3362 guarantee(use_local_bitmaps, "invariant"); | |
| 3363 assert(fields_well_formed(), "invariant"); | |
| 3364 | |
| 3365 return at(heapWordToOffset(addr)); | |
| 3366 } | |
| 3367 | |
| 3368 void set_buffer(HeapWord* start) { | |
| 3369 guarantee(use_local_bitmaps, "invariant"); | |
| 3370 clear(); | |
| 3371 | |
| 3372 assert(start != NULL, "invariant"); | |
| 3373 _real_start_word = start; | |
| 3374 _real_end_word = start + _gclab_word_size; | |
| 3375 | |
| 3376 size_t diff = | |
| 3377 pointer_delta(start, _heap_start) % _bitmap_word_covers_words; | |
| 3378 _start_word = start - diff; | |
| 3379 | |
| 3380 assert(fields_well_formed(), "invariant"); | |
| 3381 } | |
| 3382 | |
| 3383 #ifndef PRODUCT | |
| 3384 void verify() { | |
| 3385 // verify that the marks have been propagated | |
| 3386 GCLabBitMapClosure cl(_cm, this); | |
| 3387 iterate(&cl); | |
| 3388 } | |
| 3389 #endif // PRODUCT | |
| 3390 | |
| 3391 void retire() { | |
| 3392 guarantee(use_local_bitmaps, "invariant"); | |
| 3393 assert(fields_well_formed(), "invariant"); | |
| 3394 | |
| 3395 if (_start_word != NULL) { | |
| 3396 CMBitMap* mark_bitmap = _cm->nextMarkBitMap(); | |
| 3397 | |
| 3398 // this means that the bitmap was set up for the GCLab | |
| 3399 assert(_real_start_word != NULL && _real_end_word != NULL, "invariant"); | |
| 3400 | |
| 3401 mark_bitmap->mostly_disjoint_range_union(this, | |
| 3402 0, // always start from the start of the bitmap | |
| 3403 _start_word, | |
| 3404 size_in_words()); | |
| 3405 _cm->grayRegionIfNecessary(MemRegion(_real_start_word, _real_end_word)); | |
| 3406 | |
| 3407 #ifndef PRODUCT | |
| 3408 if (use_local_bitmaps && verify_local_bitmaps) | |
| 3409 verify(); | |
| 3410 #endif // PRODUCT | |
| 3411 } else { | |
| 3412 assert(_real_start_word == NULL && _real_end_word == NULL, "invariant"); | |
| 3413 } | |
| 3414 } | |
| 3415 | |
| 3416 static size_t bitmap_size_in_words() { | |
| 3417 return (bitmap_size_in_bits() + BitsPerWord - 1) / BitsPerWord; | |
| 3418 } | |
| 3419 }; | |
| 3420 | |
| 3421 #ifndef PRODUCT | |
| 3422 | |
| 3423 bool GCLabBitMapClosure::do_bit(size_t offset) { | |
| 3424 HeapWord* addr = _bitmap->offsetToHeapWord(offset); | |
| 3425 guarantee(_cm->isMarked(oop(addr)), "it should be!"); | |
| 3426 return true; | |
| 3427 } | |
| 3428 | |
| 3429 #endif // PRODUCT | |
| 3430 | |
| 3431 class G1ParGCAllocBuffer: public ParGCAllocBuffer { | |
| 3432 private: | |
| 3433 bool _retired; | |
| 3434 bool _during_marking; | |
| 3435 GCLabBitMap _bitmap; | |
| 3436 | |
| 3437 public: | |
| 3438 G1ParGCAllocBuffer() : | |
| 3439 ParGCAllocBuffer(ParallelGCG1AllocBufferSize / HeapWordSize), | |
| 3440 _during_marking(G1CollectedHeap::heap()->mark_in_progress()), | |
| 3441 _bitmap(G1CollectedHeap::heap()->reserved_region().start()), | |
| 3442 _retired(false) | |
| 3443 { } | |
| 3444 | |
| 3445 inline bool mark(HeapWord* addr) { | |
| 3446 guarantee(use_local_bitmaps, "invariant"); | |
| 3447 assert(_during_marking, "invariant"); | |
| 3448 return _bitmap.mark(addr); | |
| 3449 } | |
| 3450 | |
| 3451 inline void set_buf(HeapWord* buf) { | |
| 3452 if (use_local_bitmaps && _during_marking) | |
| 3453 _bitmap.set_buffer(buf); | |
| 3454 ParGCAllocBuffer::set_buf(buf); | |
| 3455 _retired = false; | |
| 3456 } | |
| 3457 | |
| 3458 inline void retire(bool end_of_gc, bool retain) { | |
| 3459 if (_retired) | |
| 3460 return; | |
| 3461 if (use_local_bitmaps && _during_marking) { | |
| 3462 _bitmap.retire(); | |
| 3463 } | |
| 3464 ParGCAllocBuffer::retire(end_of_gc, retain); | |
| 3465 _retired = true; | |
| 3466 } | |
| 3467 }; | |
| 3468 | |
| 3469 | |
| 3470 class G1ParScanThreadState : public StackObj { | |
| 3471 protected: | |
| 3472 G1CollectedHeap* _g1h; | |
| 3473 RefToScanQueue* _refs; | |
| 3474 | |
| 3475 typedef GrowableArray<oop*> OverflowQueue; | |
| 3476 OverflowQueue* _overflowed_refs; | |
| 3477 | |
| 3478 G1ParGCAllocBuffer _alloc_buffers[GCAllocPurposeCount]; | |
| 3479 | |
| 3480 size_t _alloc_buffer_waste; | |
| 3481 size_t _undo_waste; | |
| 3482 | |
| 3483 OopsInHeapRegionClosure* _evac_failure_cl; | |
| 3484 G1ParScanHeapEvacClosure* _evac_cl; | |
| 3485 G1ParScanPartialArrayClosure* _partial_scan_cl; | |
| 3486 | |
| 3487 int _hash_seed; | |
| 3488 int _queue_num; | |
| 3489 | |
| 3490 int _term_attempts; | |
| 3491 #if G1_DETAILED_STATS | |
| 3492 int _pushes, _pops, _steals, _steal_attempts; | |
| 3493 int _overflow_pushes; | |
| 3494 #endif | |
| 3495 | |
| 3496 double _start; | |
| 3497 double _start_strong_roots; | |
| 3498 double _strong_roots_time; | |
| 3499 double _start_term; | |
| 3500 double _term_time; | |
| 3501 | |
| 3502 // Map from young-age-index (0 == not young, 1 is youngest) to | |
| 3503 // surviving words. base is what we get back from the malloc call | |
| 3504 size_t* _surviving_young_words_base; | |
| 3505 // this points into the array, as we use the first few entries for padding | |
| 3506 size_t* _surviving_young_words; | |
| 3507 | |
| 3508 #define PADDING_ELEM_NUM (64 / sizeof(size_t)) | |
| 3509 | |
| 3510 void add_to_alloc_buffer_waste(size_t waste) { _alloc_buffer_waste += waste; } | |
| 3511 | |
| 3512 void add_to_undo_waste(size_t waste) { _undo_waste += waste; } | |
| 3513 | |
| 3514 public: | |
| 3515 G1ParScanThreadState(G1CollectedHeap* g1h, int queue_num) | |
| 3516 : _g1h(g1h), | |
| 3517 _refs(g1h->task_queue(queue_num)), | |
| 3518 _hash_seed(17), _queue_num(queue_num), | |
| 3519 _term_attempts(0), | |
| 3520 #if G1_DETAILED_STATS | |
| 3521 _pushes(0), _pops(0), _steals(0), | |
| 3522 _steal_attempts(0), _overflow_pushes(0), | |
| 3523 #endif | |
| 3524 _strong_roots_time(0), _term_time(0), | |
| 3525 _alloc_buffer_waste(0), _undo_waste(0) | |
| 3526 { | |
| 3527 // we allocate G1YoungSurvRateNumRegions plus one entries, since | |
| 3528 // we "sacrifice" entry 0 to keep track of surviving bytes for | |
| 3529 // non-young regions (where the age is -1) | |
| 3530 // We also add a few elements at the beginning and at the end in | |
| 3531 // an attempt to eliminate cache contention | |
| 3532 size_t real_length = 1 + _g1h->g1_policy()->young_cset_length(); | |
| 3533 size_t array_length = PADDING_ELEM_NUM + | |
| 3534 real_length + | |
| 3535 PADDING_ELEM_NUM; | |
| 3536 _surviving_young_words_base = NEW_C_HEAP_ARRAY(size_t, array_length); | |
| 3537 if (_surviving_young_words_base == NULL) | |
| 3538 vm_exit_out_of_memory(array_length * sizeof(size_t), | |
| 3539 "Not enough space for young surv histo."); | |
| 3540 _surviving_young_words = _surviving_young_words_base + PADDING_ELEM_NUM; | |
| 3541 memset(_surviving_young_words, 0, real_length * sizeof(size_t)); | |
| 3542 | |
| 3543 _overflowed_refs = new OverflowQueue(10); | |
| 3544 | |
| 3545 _start = os::elapsedTime(); | |
| 3546 } | |
| 3547 | |
| 3548 ~G1ParScanThreadState() { | |
| 3549 FREE_C_HEAP_ARRAY(size_t, _surviving_young_words_base); | |
| 3550 } | |
| 3551 | |
| 3552 RefToScanQueue* refs() { return _refs; } | |
| 3553 OverflowQueue* overflowed_refs() { return _overflowed_refs; } | |
| 3554 | |
| 3555 inline G1ParGCAllocBuffer* alloc_buffer(GCAllocPurpose purpose) { | |
| 3556 return &_alloc_buffers[purpose]; | |
| 3557 } | |
| 3558 | |
| 3559 size_t alloc_buffer_waste() { return _alloc_buffer_waste; } | |
| 3560 size_t undo_waste() { return _undo_waste; } | |
| 3561 | |
| 3562 void push_on_queue(oop* ref) { | |
| 3563 if (!refs()->push(ref)) { | |
| 3564 overflowed_refs()->push(ref); | |
| 3565 IF_G1_DETAILED_STATS(note_overflow_push()); | |
| 3566 } else { | |
| 3567 IF_G1_DETAILED_STATS(note_push()); | |
| 3568 } | |
| 3569 } | |
| 3570 | |
| 3571 void pop_from_queue(oop*& ref) { | |
| 3572 if (!refs()->pop_local(ref)) { | |
| 3573 ref = NULL; | |
| 3574 } else { | |
| 3575 IF_G1_DETAILED_STATS(note_pop()); | |
| 3576 } | |
| 3577 } | |
| 3578 | |
| 3579 void pop_from_overflow_queue(oop*& ref) { | |
| 3580 ref = overflowed_refs()->pop(); | |
| 3581 } | |
| 3582 | |
| 3583 int refs_to_scan() { return refs()->size(); } | |
| 3584 int overflowed_refs_to_scan() { return overflowed_refs()->length(); } | |
| 3585 | |
| 3586 HeapWord* allocate_slow(GCAllocPurpose purpose, size_t word_sz) { | |
| 3587 | |
| 3588 HeapWord* obj = NULL; | |
| 3589 if (word_sz * 100 < | |
| 3590 (size_t)(ParallelGCG1AllocBufferSize / HeapWordSize) * | |
| 3591 ParallelGCBufferWastePct) { | |
| 3592 G1ParGCAllocBuffer* alloc_buf = alloc_buffer(purpose); | |
| 3593 add_to_alloc_buffer_waste(alloc_buf->words_remaining()); | |
| 3594 alloc_buf->retire(false, false); | |
| 3595 | |
| 3596 HeapWord* buf = | |
| 3597 _g1h->par_allocate_during_gc(purpose, ParallelGCG1AllocBufferSize / HeapWordSize); | |
| 3598 if (buf == NULL) return NULL; // Let caller handle allocation failure. | |
| 3599 // Otherwise. | |
| 3600 alloc_buf->set_buf(buf); | |
| 3601 | |
| 3602 obj = alloc_buf->allocate(word_sz); | |
| 3603 assert(obj != NULL, "buffer was definitely big enough..."); | |
| 3604 } | |
| 3605 else { | |
| 3606 obj = _g1h->par_allocate_during_gc(purpose, word_sz); | |
| 3607 } | |
| 3608 return obj; | |
| 3609 } | |
| 3610 | |
| 3611 HeapWord* allocate(GCAllocPurpose purpose, size_t word_sz) { | |
| 3612 HeapWord* obj = alloc_buffer(purpose)->allocate(word_sz); | |
| 3613 if (obj != NULL) return obj; | |
| 3614 return allocate_slow(purpose, word_sz); | |
| 3615 } | |
| 3616 | |
| 3617 void undo_allocation(GCAllocPurpose purpose, HeapWord* obj, size_t word_sz) { | |
| 3618 if (alloc_buffer(purpose)->contains(obj)) { | |
| 3619 guarantee(alloc_buffer(purpose)->contains(obj + word_sz - 1), | |
| 3620 "should contain whole object"); | |
| 3621 alloc_buffer(purpose)->undo_allocation(obj, word_sz); | |
|
481
7d7a7c599c17
6578152: fill_region_with_object has usability and safety issues
jcoomes
parents:
457
diff
changeset
|
3622 } else { |
|
7d7a7c599c17
6578152: fill_region_with_object has usability and safety issues
jcoomes
parents:
457
diff
changeset
|
3623 CollectedHeap::fill_with_object(obj, word_sz); |
| 342 | 3624 add_to_undo_waste(word_sz); |
| 3625 } | |
| 3626 } | |
| 3627 | |
| 3628 void set_evac_failure_closure(OopsInHeapRegionClosure* evac_failure_cl) { | |
| 3629 _evac_failure_cl = evac_failure_cl; | |
| 3630 } | |
| 3631 OopsInHeapRegionClosure* evac_failure_closure() { | |
| 3632 return _evac_failure_cl; | |
| 3633 } | |
| 3634 | |
| 3635 void set_evac_closure(G1ParScanHeapEvacClosure* evac_cl) { | |
| 3636 _evac_cl = evac_cl; | |
| 3637 } | |
| 3638 | |
| 3639 void set_partial_scan_closure(G1ParScanPartialArrayClosure* partial_scan_cl) { | |
| 3640 _partial_scan_cl = partial_scan_cl; | |
| 3641 } | |
| 3642 | |
| 3643 int* hash_seed() { return &_hash_seed; } | |
| 3644 int queue_num() { return _queue_num; } | |
| 3645 | |
| 3646 int term_attempts() { return _term_attempts; } | |
| 3647 void note_term_attempt() { _term_attempts++; } | |
| 3648 | |
| 3649 #if G1_DETAILED_STATS | |
| 3650 int pushes() { return _pushes; } | |
| 3651 int pops() { return _pops; } | |
| 3652 int steals() { return _steals; } | |
| 3653 int steal_attempts() { return _steal_attempts; } | |
| 3654 int overflow_pushes() { return _overflow_pushes; } | |
| 3655 | |
| 3656 void note_push() { _pushes++; } | |
| 3657 void note_pop() { _pops++; } | |
| 3658 void note_steal() { _steals++; } | |
| 3659 void note_steal_attempt() { _steal_attempts++; } | |
| 3660 void note_overflow_push() { _overflow_pushes++; } | |
| 3661 #endif | |
| 3662 | |
| 3663 void start_strong_roots() { | |
| 3664 _start_strong_roots = os::elapsedTime(); | |
| 3665 } | |
| 3666 void end_strong_roots() { | |
| 3667 _strong_roots_time += (os::elapsedTime() - _start_strong_roots); | |
| 3668 } | |
| 3669 double strong_roots_time() { return _strong_roots_time; } | |
| 3670 | |
| 3671 void start_term_time() { | |
| 3672 note_term_attempt(); | |
| 3673 _start_term = os::elapsedTime(); | |
| 3674 } | |
| 3675 void end_term_time() { | |
| 3676 _term_time += (os::elapsedTime() - _start_term); | |
| 3677 } | |
| 3678 double term_time() { return _term_time; } | |
| 3679 | |
| 3680 double elapsed() { | |
| 3681 return os::elapsedTime() - _start; | |
| 3682 } | |
| 3683 | |
| 3684 size_t* surviving_young_words() { | |
| 3685 // We add on to hide entry 0 which accumulates surviving words for | |
| 3686 // age -1 regions (i.e. non-young ones) | |
| 3687 return _surviving_young_words; | |
| 3688 } | |
| 3689 | |
| 3690 void retire_alloc_buffers() { | |
| 3691 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) { | |
| 3692 size_t waste = _alloc_buffers[ap].words_remaining(); | |
| 3693 add_to_alloc_buffer_waste(waste); | |
| 3694 _alloc_buffers[ap].retire(true, false); | |
| 3695 } | |
| 3696 } | |
| 3697 | |
| 3698 void trim_queue() { | |
| 3699 while (refs_to_scan() > 0 || overflowed_refs_to_scan() > 0) { | |
| 3700 oop *ref_to_scan = NULL; | |
| 3701 if (overflowed_refs_to_scan() == 0) { | |
| 3702 pop_from_queue(ref_to_scan); | |
| 3703 } else { | |
| 3704 pop_from_overflow_queue(ref_to_scan); | |
| 3705 } | |
| 3706 if (ref_to_scan != NULL) { | |
| 3707 if ((intptr_t)ref_to_scan & G1_PARTIAL_ARRAY_MASK) { | |
| 3708 _partial_scan_cl->do_oop_nv(ref_to_scan); | |
| 3709 } else { | |
| 3710 // Note: we can use "raw" versions of "region_containing" because | |
| 3711 // "obj_to_scan" is definitely in the heap, and is not in a | |
| 3712 // humongous region. | |
| 3713 HeapRegion* r = _g1h->heap_region_containing_raw(ref_to_scan); | |
| 3714 _evac_cl->set_region(r); | |
| 3715 _evac_cl->do_oop_nv(ref_to_scan); | |
| 3716 } | |
| 3717 } | |
| 3718 } | |
| 3719 } | |
| 3720 }; | |
| 3721 | |
| 3722 | |
| 3723 G1ParClosureSuper::G1ParClosureSuper(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state) : | |
| 3724 _g1(g1), _g1_rem(_g1->g1_rem_set()), _cm(_g1->concurrent_mark()), | |
| 3725 _par_scan_state(par_scan_state) { } | |
| 3726 | |
| 3727 // This closure is applied to the fields of the objects that have just been copied. | |
| 3728 // Should probably be made inline and moved in g1OopClosures.inline.hpp. | |
| 3729 void G1ParScanClosure::do_oop_nv(oop* p) { | |
| 3730 oop obj = *p; | |
| 3731 if (obj != NULL) { | |
| 3732 if (_g1->obj_in_cs(obj)) { | |
| 3733 if (obj->is_forwarded()) { | |
| 3734 *p = obj->forwardee(); | |
| 3735 } else { | |
| 3736 _par_scan_state->push_on_queue(p); | |
| 3737 return; | |
| 3738 } | |
| 3739 } | |
| 3740 _g1_rem->par_write_ref(_from, p, _par_scan_state->queue_num()); | |
| 3741 } | |
| 3742 } | |
| 3743 | |
| 3744 void G1ParCopyHelper::mark_forwardee(oop* p) { | |
| 3745 // This is called _after_ do_oop_work has been called, hence after | |
| 3746 // the object has been relocated to its new location and *p points | |
| 3747 // to its new location. | |
| 3748 | |
| 3749 oop thisOop = *p; | |
| 3750 if (thisOop != NULL) { | |
| 3751 assert((_g1->evacuation_failed()) || (!_g1->obj_in_cs(thisOop)), | |
| 3752 "shouldn't still be in the CSet if evacuation didn't fail."); | |
| 3753 HeapWord* addr = (HeapWord*)thisOop; | |
| 3754 if (_g1->is_in_g1_reserved(addr)) | |
| 3755 _cm->grayRoot(oop(addr)); | |
| 3756 } | |
| 3757 } | |
| 3758 | |
| 3759 oop G1ParCopyHelper::copy_to_survivor_space(oop old) { | |
| 3760 size_t word_sz = old->size(); | |
| 3761 HeapRegion* from_region = _g1->heap_region_containing_raw(old); | |
| 3762 // +1 to make the -1 indexes valid... | |
| 3763 int young_index = from_region->young_index_in_cset()+1; | |
| 3764 assert( (from_region->is_young() && young_index > 0) || | |
| 3765 (!from_region->is_young() && young_index == 0), "invariant" ); | |
| 3766 G1CollectorPolicy* g1p = _g1->g1_policy(); | |
| 3767 markOop m = old->mark(); | |
| 3768 GCAllocPurpose alloc_purpose = g1p->evacuation_destination(from_region, m->age(), | |
| 3769 word_sz); | |
| 3770 HeapWord* obj_ptr = _par_scan_state->allocate(alloc_purpose, word_sz); | |
| 3771 oop obj = oop(obj_ptr); | |
| 3772 | |
| 3773 if (obj_ptr == NULL) { | |
| 3774 // This will either forward-to-self, or detect that someone else has | |
| 3775 // installed a forwarding pointer. | |
| 3776 OopsInHeapRegionClosure* cl = _par_scan_state->evac_failure_closure(); | |
| 3777 return _g1->handle_evacuation_failure_par(cl, old); | |
| 3778 } | |
| 3779 | |
| 3780 oop forward_ptr = old->forward_to_atomic(obj); | |
| 3781 if (forward_ptr == NULL) { | |
| 3782 Copy::aligned_disjoint_words((HeapWord*) old, obj_ptr, word_sz); | |
| 3783 obj->set_mark(m); | |
| 3784 if (g1p->track_object_age(alloc_purpose)) { | |
| 3785 obj->incr_age(); | |
| 3786 } | |
| 3787 // preserve "next" mark bit | |
| 3788 if (_g1->mark_in_progress() && !_g1->is_obj_ill(old)) { | |
| 3789 if (!use_local_bitmaps || | |
| 3790 !_par_scan_state->alloc_buffer(alloc_purpose)->mark(obj_ptr)) { | |
| 3791 // if we couldn't mark it on the local bitmap (this happens when | |
| 3792 // the object was not allocated in the GCLab), we have to bite | |
| 3793 // the bullet and do the standard parallel mark | |
| 3794 _cm->markAndGrayObjectIfNecessary(obj); | |
| 3795 } | |
| 3796 #if 1 | |
| 3797 if (_g1->isMarkedNext(old)) { | |
| 3798 _cm->nextMarkBitMap()->parClear((HeapWord*)old); | |
| 3799 } | |
| 3800 #endif | |
| 3801 } | |
| 3802 | |
| 3803 size_t* surv_young_words = _par_scan_state->surviving_young_words(); | |
| 3804 surv_young_words[young_index] += word_sz; | |
| 3805 | |
| 3806 if (obj->is_objArray() && arrayOop(obj)->length() >= ParGCArrayScanChunk) { | |
| 3807 arrayOop(old)->set_length(0); | |
| 3808 _par_scan_state->push_on_queue((oop*) ((intptr_t)old | G1_PARTIAL_ARRAY_MASK)); | |
| 3809 } else { | |
| 3810 _scanner->set_region(_g1->heap_region_containing(obj)); | |
| 3811 obj->oop_iterate_backwards(_scanner); | |
| 3812 } | |
| 3813 } else { | |
| 3814 _par_scan_state->undo_allocation(alloc_purpose, obj_ptr, word_sz); | |
| 3815 obj = forward_ptr; | |
| 3816 } | |
| 3817 return obj; | |
| 3818 } | |
| 3819 | |
| 3820 template<bool do_gen_barrier, G1Barrier barrier, bool do_mark_forwardee> | |
| 3821 void G1ParCopyClosure<do_gen_barrier, barrier, do_mark_forwardee>::do_oop_work(oop* p) { | |
| 3822 oop obj = *p; | |
| 3823 assert(barrier != G1BarrierRS || obj != NULL, | |
| 3824 "Precondition: G1BarrierRS implies obj is nonNull"); | |
| 3825 | |
| 3826 if (obj != NULL) { | |
| 3827 if (_g1->obj_in_cs(obj)) { | |
| 3828 #if G1_REM_SET_LOGGING | |
| 3829 gclog_or_tty->print_cr("Loc "PTR_FORMAT" contains pointer "PTR_FORMAT" into CS.", | |
| 3830 p, (void*) obj); | |
| 3831 #endif | |
| 3832 if (obj->is_forwarded()) { | |
| 3833 *p = obj->forwardee(); | |
| 3834 } else { | |
| 3835 *p = copy_to_survivor_space(obj); | |
| 3836 } | |
| 3837 // When scanning the RS, we only care about objs in CS. | |
| 3838 if (barrier == G1BarrierRS) { | |
| 3839 _g1_rem->par_write_ref(_from, p, _par_scan_state->queue_num()); | |
| 3840 } | |
| 3841 } | |
| 3842 // When scanning moved objs, must look at all oops. | |
| 3843 if (barrier == G1BarrierEvac) { | |
| 3844 _g1_rem->par_write_ref(_from, p, _par_scan_state->queue_num()); | |
| 3845 } | |
| 3846 | |
| 3847 if (do_gen_barrier) { | |
| 3848 par_do_barrier(p); | |
| 3849 } | |
| 3850 } | |
| 3851 } | |
| 3852 | |
| 3853 template void G1ParCopyClosure<false, G1BarrierEvac, false>::do_oop_work(oop* p); | |
| 3854 | |
| 3855 template <class T> void G1ParScanPartialArrayClosure::process_array_chunk( | |
| 3856 oop obj, int start, int end) { | |
| 3857 // process our set of indices (include header in first chunk) | |
| 3858 assert(start < end, "invariant"); | |
| 3859 T* const base = (T*)objArrayOop(obj)->base(); | |
| 3860 T* const start_addr = base + start; | |
| 3861 T* const end_addr = base + end; | |
| 3862 MemRegion mr((HeapWord*)start_addr, (HeapWord*)end_addr); | |
| 3863 _scanner.set_region(_g1->heap_region_containing(obj)); | |
| 3864 obj->oop_iterate(&_scanner, mr); | |
| 3865 } | |
| 3866 | |
| 3867 void G1ParScanPartialArrayClosure::do_oop_nv(oop* p) { | |
| 3868 assert(!UseCompressedOops, "Needs to be fixed to work with compressed oops"); | |
| 3869 oop old = oop((intptr_t)p & ~G1_PARTIAL_ARRAY_MASK); | |
| 3870 assert(old->is_objArray(), "must be obj array"); | |
| 3871 assert(old->is_forwarded(), "must be forwarded"); | |
| 3872 assert(Universe::heap()->is_in_reserved(old), "must be in heap."); | |
| 3873 | |
| 3874 objArrayOop obj = objArrayOop(old->forwardee()); | |
| 3875 assert((void*)old != (void*)old->forwardee(), "self forwarding here?"); | |
| 3876 // Process ParGCArrayScanChunk elements now | |
| 3877 // and push the remainder back onto queue | |
| 3878 int start = arrayOop(old)->length(); | |
| 3879 int end = obj->length(); | |
| 3880 int remainder = end - start; | |
| 3881 assert(start <= end, "just checking"); | |
| 3882 if (remainder > 2 * ParGCArrayScanChunk) { | |
| 3883 // Test above combines last partial chunk with a full chunk | |
| 3884 end = start + ParGCArrayScanChunk; | |
| 3885 arrayOop(old)->set_length(end); | |
| 3886 // Push remainder. | |
| 3887 _par_scan_state->push_on_queue((oop*) ((intptr_t) old | G1_PARTIAL_ARRAY_MASK)); | |
| 3888 } else { | |
| 3889 // Restore length so that the heap remains parsable in | |
| 3890 // case of evacuation failure. | |
| 3891 arrayOop(old)->set_length(end); | |
| 3892 } | |
| 3893 | |
| 3894 // process our set of indices (include header in first chunk) | |
| 3895 process_array_chunk<oop>(obj, start, end); | |
| 3896 oop* start_addr = start == 0 ? (oop*)obj : obj->obj_at_addr<oop>(start); | |
| 3897 oop* end_addr = (oop*)(obj->base()) + end; // obj_at_addr(end) asserts end < length | |
| 3898 MemRegion mr((HeapWord*)start_addr, (HeapWord*)end_addr); | |
| 3899 _scanner.set_region(_g1->heap_region_containing(obj)); | |
| 3900 obj->oop_iterate(&_scanner, mr); | |
| 3901 } | |
| 3902 | |
| 3903 int G1ScanAndBalanceClosure::_nq = 0; | |
| 3904 | |
| 3905 class G1ParEvacuateFollowersClosure : public VoidClosure { | |
| 3906 protected: | |
| 3907 G1CollectedHeap* _g1h; | |
| 3908 G1ParScanThreadState* _par_scan_state; | |
| 3909 RefToScanQueueSet* _queues; | |
| 3910 ParallelTaskTerminator* _terminator; | |
| 3911 | |
| 3912 G1ParScanThreadState* par_scan_state() { return _par_scan_state; } | |
| 3913 RefToScanQueueSet* queues() { return _queues; } | |
| 3914 ParallelTaskTerminator* terminator() { return _terminator; } | |
| 3915 | |
| 3916 public: | |
| 3917 G1ParEvacuateFollowersClosure(G1CollectedHeap* g1h, | |
| 3918 G1ParScanThreadState* par_scan_state, | |
| 3919 RefToScanQueueSet* queues, | |
| 3920 ParallelTaskTerminator* terminator) | |
| 3921 : _g1h(g1h), _par_scan_state(par_scan_state), | |
| 3922 _queues(queues), _terminator(terminator) {} | |
| 3923 | |
| 3924 void do_void() { | |
| 3925 G1ParScanThreadState* pss = par_scan_state(); | |
| 3926 while (true) { | |
| 3927 oop* ref_to_scan; | |
| 3928 pss->trim_queue(); | |
| 3929 IF_G1_DETAILED_STATS(pss->note_steal_attempt()); | |
| 3930 if (queues()->steal(pss->queue_num(), | |
| 3931 pss->hash_seed(), | |
| 3932 ref_to_scan)) { | |
| 3933 IF_G1_DETAILED_STATS(pss->note_steal()); | |
| 3934 pss->push_on_queue(ref_to_scan); | |
| 3935 continue; | |
| 3936 } | |
| 3937 pss->start_term_time(); | |
| 3938 if (terminator()->offer_termination()) break; | |
| 3939 pss->end_term_time(); | |
| 3940 } | |
| 3941 pss->end_term_time(); | |
| 3942 pss->retire_alloc_buffers(); | |
| 3943 } | |
| 3944 }; | |
| 3945 | |
| 3946 class G1ParTask : public AbstractGangTask { | |
| 3947 protected: | |
| 3948 G1CollectedHeap* _g1h; | |
| 3949 RefToScanQueueSet *_queues; | |
| 3950 ParallelTaskTerminator _terminator; | |
| 3951 | |
| 3952 Mutex _stats_lock; | |
| 3953 Mutex* stats_lock() { return &_stats_lock; } | |
| 3954 | |
| 3955 size_t getNCards() { | |
| 3956 return (_g1h->capacity() + G1BlockOffsetSharedArray::N_bytes - 1) | |
| 3957 / G1BlockOffsetSharedArray::N_bytes; | |
| 3958 } | |
| 3959 | |
| 3960 public: | |
| 3961 G1ParTask(G1CollectedHeap* g1h, int workers, RefToScanQueueSet *task_queues) | |
| 3962 : AbstractGangTask("G1 collection"), | |
| 3963 _g1h(g1h), | |
| 3964 _queues(task_queues), | |
| 3965 _terminator(workers, _queues), | |
| 3966 _stats_lock(Mutex::leaf, "parallel G1 stats lock", true) | |
| 3967 {} | |
| 3968 | |
| 3969 RefToScanQueueSet* queues() { return _queues; } | |
| 3970 | |
| 3971 RefToScanQueue *work_queue(int i) { | |
| 3972 return queues()->queue(i); | |
| 3973 } | |
| 3974 | |
| 3975 void work(int i) { | |
| 3976 ResourceMark rm; | |
| 3977 HandleMark hm; | |
| 3978 | |
| 3979 G1ParScanThreadState pss(_g1h, i); | |
| 3980 G1ParScanHeapEvacClosure scan_evac_cl(_g1h, &pss); | |
| 3981 G1ParScanHeapEvacClosure evac_failure_cl(_g1h, &pss); | |
| 3982 G1ParScanPartialArrayClosure partial_scan_cl(_g1h, &pss); | |
| 3983 | |
| 3984 pss.set_evac_closure(&scan_evac_cl); | |
| 3985 pss.set_evac_failure_closure(&evac_failure_cl); | |
| 3986 pss.set_partial_scan_closure(&partial_scan_cl); | |
| 3987 | |
| 3988 G1ParScanExtRootClosure only_scan_root_cl(_g1h, &pss); | |
| 3989 G1ParScanPermClosure only_scan_perm_cl(_g1h, &pss); | |
| 3990 G1ParScanHeapRSClosure only_scan_heap_rs_cl(_g1h, &pss); | |
| 3991 G1ParScanAndMarkExtRootClosure scan_mark_root_cl(_g1h, &pss); | |
| 3992 G1ParScanAndMarkPermClosure scan_mark_perm_cl(_g1h, &pss); | |
| 3993 G1ParScanAndMarkHeapRSClosure scan_mark_heap_rs_cl(_g1h, &pss); | |
| 3994 | |
| 3995 OopsInHeapRegionClosure *scan_root_cl; | |
| 3996 OopsInHeapRegionClosure *scan_perm_cl; | |
| 3997 OopsInHeapRegionClosure *scan_so_cl; | |
| 3998 | |
| 3999 if (_g1h->g1_policy()->should_initiate_conc_mark()) { | |
| 4000 scan_root_cl = &scan_mark_root_cl; | |
| 4001 scan_perm_cl = &scan_mark_perm_cl; | |
| 4002 scan_so_cl = &scan_mark_heap_rs_cl; | |
| 4003 } else { | |
| 4004 scan_root_cl = &only_scan_root_cl; | |
| 4005 scan_perm_cl = &only_scan_perm_cl; | |
| 4006 scan_so_cl = &only_scan_heap_rs_cl; | |
| 4007 } | |
| 4008 | |
| 4009 pss.start_strong_roots(); | |
| 4010 _g1h->g1_process_strong_roots(/* not collecting perm */ false, | |
| 4011 SharedHeap::SO_AllClasses, | |
| 4012 scan_root_cl, | |
| 4013 &only_scan_heap_rs_cl, | |
| 4014 scan_so_cl, | |
| 4015 scan_perm_cl, | |
| 4016 i); | |
| 4017 pss.end_strong_roots(); | |
| 4018 { | |
| 4019 double start = os::elapsedTime(); | |
| 4020 G1ParEvacuateFollowersClosure evac(_g1h, &pss, _queues, &_terminator); | |
| 4021 evac.do_void(); | |
| 4022 double elapsed_ms = (os::elapsedTime()-start)*1000.0; | |
| 4023 double term_ms = pss.term_time()*1000.0; | |
| 4024 _g1h->g1_policy()->record_obj_copy_time(i, elapsed_ms-term_ms); | |
| 4025 _g1h->g1_policy()->record_termination_time(i, term_ms); | |
| 4026 } | |
| 4027 _g1h->update_surviving_young_words(pss.surviving_young_words()+1); | |
| 4028 | |
| 4029 // Clean up any par-expanded rem sets. | |
| 4030 HeapRegionRemSet::par_cleanup(); | |
| 4031 | |
| 4032 MutexLocker x(stats_lock()); | |
| 4033 if (ParallelGCVerbose) { | |
| 4034 gclog_or_tty->print("Thread %d complete:\n", i); | |
| 4035 #if G1_DETAILED_STATS | |
| 4036 gclog_or_tty->print(" Pushes: %7d Pops: %7d Overflows: %7d Steals %7d (in %d attempts)\n", | |
| 4037 pss.pushes(), | |
| 4038 pss.pops(), | |
| 4039 pss.overflow_pushes(), | |
| 4040 pss.steals(), | |
| 4041 pss.steal_attempts()); | |
| 4042 #endif | |
| 4043 double elapsed = pss.elapsed(); | |
| 4044 double strong_roots = pss.strong_roots_time(); | |
| 4045 double term = pss.term_time(); | |
| 4046 gclog_or_tty->print(" Elapsed: %7.2f ms.\n" | |
| 4047 " Strong roots: %7.2f ms (%6.2f%%)\n" | |
| 4048 " Termination: %7.2f ms (%6.2f%%) (in %d entries)\n", | |
| 4049 elapsed * 1000.0, | |
| 4050 strong_roots * 1000.0, (strong_roots*100.0/elapsed), | |
| 4051 term * 1000.0, (term*100.0/elapsed), | |
| 4052 pss.term_attempts()); | |
| 4053 size_t total_waste = pss.alloc_buffer_waste() + pss.undo_waste(); | |
| 4054 gclog_or_tty->print(" Waste: %8dK\n" | |
| 4055 " Alloc Buffer: %8dK\n" | |
| 4056 " Undo: %8dK\n", | |
| 4057 (total_waste * HeapWordSize) / K, | |
| 4058 (pss.alloc_buffer_waste() * HeapWordSize) / K, | |
| 4059 (pss.undo_waste() * HeapWordSize) / K); | |
| 4060 } | |
| 4061 | |
| 4062 assert(pss.refs_to_scan() == 0, "Task queue should be empty"); | |
| 4063 assert(pss.overflowed_refs_to_scan() == 0, "Overflow queue should be empty"); | |
| 4064 } | |
| 4065 }; | |
| 4066 | |
| 4067 // *** Common G1 Evacuation Stuff | |
| 4068 | |
| 4069 class G1CountClosure: public OopsInHeapRegionClosure { | |
| 4070 public: | |
| 4071 int n; | |
| 4072 G1CountClosure() : n(0) {} | |
| 4073 void do_oop(narrowOop* p) { | |
| 4074 guarantee(false, "NYI"); | |
| 4075 } | |
| 4076 void do_oop(oop* p) { | |
| 4077 oop obj = *p; | |
| 4078 assert(obj != NULL && G1CollectedHeap::heap()->obj_in_cs(obj), | |
| 4079 "Rem set closure called on non-rem-set pointer."); | |
| 4080 n++; | |
| 4081 } | |
| 4082 }; | |
| 4083 | |
| 4084 static G1CountClosure count_closure; | |
| 4085 | |
| 4086 void | |
| 4087 G1CollectedHeap:: | |
| 4088 g1_process_strong_roots(bool collecting_perm_gen, | |
| 4089 SharedHeap::ScanningOption so, | |
| 4090 OopClosure* scan_non_heap_roots, | |
| 4091 OopsInHeapRegionClosure* scan_rs, | |
| 4092 OopsInHeapRegionClosure* scan_so, | |
| 4093 OopsInGenClosure* scan_perm, | |
| 4094 int worker_i) { | |
| 4095 // First scan the strong roots, including the perm gen. | |
| 4096 double ext_roots_start = os::elapsedTime(); | |
| 4097 double closure_app_time_sec = 0.0; | |
| 4098 | |
| 4099 BufferingOopClosure buf_scan_non_heap_roots(scan_non_heap_roots); | |
| 4100 BufferingOopsInGenClosure buf_scan_perm(scan_perm); | |
| 4101 buf_scan_perm.set_generation(perm_gen()); | |
| 4102 | |
| 4103 process_strong_roots(collecting_perm_gen, so, | |
| 4104 &buf_scan_non_heap_roots, | |
| 4105 &buf_scan_perm); | |
| 4106 // Finish up any enqueued closure apps. | |
| 4107 buf_scan_non_heap_roots.done(); | |
| 4108 buf_scan_perm.done(); | |
| 4109 double ext_roots_end = os::elapsedTime(); | |
| 4110 g1_policy()->reset_obj_copy_time(worker_i); | |
| 4111 double obj_copy_time_sec = | |
| 4112 buf_scan_non_heap_roots.closure_app_seconds() + | |
| 4113 buf_scan_perm.closure_app_seconds(); | |
| 4114 g1_policy()->record_obj_copy_time(worker_i, obj_copy_time_sec * 1000.0); | |
| 4115 double ext_root_time_ms = | |
| 4116 ((ext_roots_end - ext_roots_start) - obj_copy_time_sec) * 1000.0; | |
| 4117 g1_policy()->record_ext_root_scan_time(worker_i, ext_root_time_ms); | |
| 4118 | |
| 4119 // Scan strong roots in mark stack. | |
| 4120 if (!_process_strong_tasks->is_task_claimed(G1H_PS_mark_stack_oops_do)) { | |
| 4121 concurrent_mark()->oops_do(scan_non_heap_roots); | |
| 4122 } | |
| 4123 double mark_stack_scan_ms = (os::elapsedTime() - ext_roots_end) * 1000.0; | |
| 4124 g1_policy()->record_mark_stack_scan_time(worker_i, mark_stack_scan_ms); | |
| 4125 | |
| 4126 // XXX What should this be doing in the parallel case? | |
| 4127 g1_policy()->record_collection_pause_end_CH_strong_roots(); | |
| 4128 if (G1VerifyRemSet) { | |
| 4129 // :::: FIXME :::: | |
| 4130 // The stupid remembered set doesn't know how to filter out dead | |
| 4131 // objects, which the smart one does, and so when it is created | |
| 4132 // and then compared the number of entries in each differs and | |
| 4133 // the verification code fails. | |
| 4134 guarantee(false, "verification code is broken, see note"); | |
| 4135 | |
| 4136 // Let's make sure that the current rem set agrees with the stupidest | |
| 4137 // one possible! | |
| 4138 bool refs_enabled = ref_processor()->discovery_enabled(); | |
| 4139 if (refs_enabled) ref_processor()->disable_discovery(); | |
| 4140 StupidG1RemSet stupid(this); | |
| 4141 count_closure.n = 0; | |
| 4142 stupid.oops_into_collection_set_do(&count_closure, worker_i); | |
| 4143 int stupid_n = count_closure.n; | |
| 4144 count_closure.n = 0; | |
| 4145 g1_rem_set()->oops_into_collection_set_do(&count_closure, worker_i); | |
| 4146 guarantee(count_closure.n == stupid_n, "Old and new rem sets differ."); | |
| 4147 gclog_or_tty->print_cr("\nFound %d pointers in heap RS.", count_closure.n); | |
| 4148 if (refs_enabled) ref_processor()->enable_discovery(); | |
| 4149 } | |
| 4150 if (scan_so != NULL) { | |
| 4151 scan_scan_only_set(scan_so, worker_i); | |
| 4152 } | |
| 4153 // Now scan the complement of the collection set. | |
| 4154 if (scan_rs != NULL) { | |
| 4155 g1_rem_set()->oops_into_collection_set_do(scan_rs, worker_i); | |
| 4156 } | |
| 4157 // Finish with the ref_processor roots. | |
| 4158 if (!_process_strong_tasks->is_task_claimed(G1H_PS_refProcessor_oops_do)) { | |
| 4159 ref_processor()->oops_do(scan_non_heap_roots); | |
| 4160 } | |
| 4161 g1_policy()->record_collection_pause_end_G1_strong_roots(); | |
| 4162 _process_strong_tasks->all_tasks_completed(); | |
| 4163 } | |
| 4164 | |
| 4165 void | |
| 4166 G1CollectedHeap::scan_scan_only_region(HeapRegion* r, | |
| 4167 OopsInHeapRegionClosure* oc, | |
| 4168 int worker_i) { | |
| 4169 HeapWord* startAddr = r->bottom(); | |
| 4170 HeapWord* endAddr = r->used_region().end(); | |
| 4171 | |
| 4172 oc->set_region(r); | |
| 4173 | |
| 4174 HeapWord* p = r->bottom(); | |
| 4175 HeapWord* t = r->top(); | |
| 4176 guarantee( p == r->next_top_at_mark_start(), "invariant" ); | |
| 4177 while (p < t) { | |
| 4178 oop obj = oop(p); | |
| 4179 p += obj->oop_iterate(oc); | |
| 4180 } | |
| 4181 } | |
| 4182 | |
| 4183 void | |
| 4184 G1CollectedHeap::scan_scan_only_set(OopsInHeapRegionClosure* oc, | |
| 4185 int worker_i) { | |
| 4186 double start = os::elapsedTime(); | |
| 4187 | |
| 4188 BufferingOopsInHeapRegionClosure boc(oc); | |
| 4189 | |
| 4190 FilterInHeapRegionAndIntoCSClosure scan_only(this, &boc); | |
| 4191 FilterAndMarkInHeapRegionAndIntoCSClosure scan_and_mark(this, &boc, concurrent_mark()); | |
| 4192 | |
| 4193 OopsInHeapRegionClosure *foc; | |
| 4194 if (g1_policy()->should_initiate_conc_mark()) | |
| 4195 foc = &scan_and_mark; | |
| 4196 else | |
| 4197 foc = &scan_only; | |
| 4198 | |
| 4199 HeapRegion* hr; | |
| 4200 int n = 0; | |
| 4201 while ((hr = _young_list->par_get_next_scan_only_region()) != NULL) { | |
| 4202 scan_scan_only_region(hr, foc, worker_i); | |
| 4203 ++n; | |
| 4204 } | |
| 4205 boc.done(); | |
| 4206 | |
| 4207 double closure_app_s = boc.closure_app_seconds(); | |
| 4208 g1_policy()->record_obj_copy_time(worker_i, closure_app_s * 1000.0); | |
| 4209 double ms = (os::elapsedTime() - start - closure_app_s)*1000.0; | |
| 4210 g1_policy()->record_scan_only_time(worker_i, ms, n); | |
| 4211 } | |
| 4212 | |
| 4213 void | |
| 4214 G1CollectedHeap::g1_process_weak_roots(OopClosure* root_closure, | |
| 4215 OopClosure* non_root_closure) { | |
| 4216 SharedHeap::process_weak_roots(root_closure, non_root_closure); | |
| 4217 } | |
| 4218 | |
| 4219 | |
| 4220 class SaveMarksClosure: public HeapRegionClosure { | |
| 4221 public: | |
| 4222 bool doHeapRegion(HeapRegion* r) { | |
| 4223 r->save_marks(); | |
| 4224 return false; | |
| 4225 } | |
| 4226 }; | |
| 4227 | |
| 4228 void G1CollectedHeap::save_marks() { | |
| 4229 if (ParallelGCThreads == 0) { | |
| 4230 SaveMarksClosure sm; | |
| 4231 heap_region_iterate(&sm); | |
| 4232 } | |
| 4233 // We do this even in the parallel case | |
| 4234 perm_gen()->save_marks(); | |
| 4235 } | |
| 4236 | |
| 4237 void G1CollectedHeap::evacuate_collection_set() { | |
| 4238 set_evacuation_failed(false); | |
| 4239 | |
| 4240 g1_rem_set()->prepare_for_oops_into_collection_set_do(); | |
| 4241 concurrent_g1_refine()->set_use_cache(false); | |
| 4242 int n_workers = (ParallelGCThreads > 0 ? workers()->total_workers() : 1); | |
| 4243 | |
| 4244 set_par_threads(n_workers); | |
| 4245 G1ParTask g1_par_task(this, n_workers, _task_queues); | |
| 4246 | |
| 4247 init_for_evac_failure(NULL); | |
| 4248 | |
| 4249 change_strong_roots_parity(); // In preparation for parallel strong roots. | |
| 4250 rem_set()->prepare_for_younger_refs_iterate(true); | |
| 4251 double start_par = os::elapsedTime(); | |
| 4252 | |
| 4253 if (ParallelGCThreads > 0) { | |
| 4254 // The individual threads will set their evac-failure closures. | |
| 4255 workers()->run_task(&g1_par_task); | |
| 4256 } else { | |
| 4257 g1_par_task.work(0); | |
| 4258 } | |
| 4259 | |
| 4260 double par_time = (os::elapsedTime() - start_par) * 1000.0; | |
| 4261 g1_policy()->record_par_time(par_time); | |
| 4262 set_par_threads(0); | |
| 4263 // Is this the right thing to do here? We don't save marks | |
| 4264 // on individual heap regions when we allocate from | |
| 4265 // them in parallel, so this seems like the correct place for this. | |
| 4266 all_alloc_regions_note_end_of_copying(); | |
| 4267 { | |
| 4268 G1IsAliveClosure is_alive(this); | |
| 4269 G1KeepAliveClosure keep_alive(this); | |
| 4270 JNIHandles::weak_oops_do(&is_alive, &keep_alive); | |
| 4271 } | |
| 4272 | |
| 4273 g1_rem_set()->cleanup_after_oops_into_collection_set_do(); | |
| 4274 concurrent_g1_refine()->set_use_cache(true); | |
| 4275 | |
| 4276 finalize_for_evac_failure(); | |
| 4277 | |
| 4278 // Must do this before removing self-forwarding pointers, which clears | |
| 4279 // the per-region evac-failure flags. | |
| 4280 concurrent_mark()->complete_marking_in_collection_set(); | |
| 4281 | |
| 4282 if (evacuation_failed()) { | |
| 4283 remove_self_forwarding_pointers(); | |
| 4284 | |
| 4285 if (PrintGCDetails) { | |
| 4286 gclog_or_tty->print(" (evacuation failed)"); | |
| 4287 } else if (PrintGC) { | |
| 4288 gclog_or_tty->print("--"); | |
| 4289 } | |
| 4290 } | |
| 4291 | |
| 4292 COMPILER2_PRESENT(DerivedPointerTable::update_pointers()); | |
| 4293 } | |
| 4294 | |
| 4295 void G1CollectedHeap::free_region(HeapRegion* hr) { | |
| 4296 size_t pre_used = 0; | |
| 4297 size_t cleared_h_regions = 0; | |
| 4298 size_t freed_regions = 0; | |
| 4299 UncleanRegionList local_list; | |
| 4300 | |
| 4301 HeapWord* start = hr->bottom(); | |
| 4302 HeapWord* end = hr->prev_top_at_mark_start(); | |
| 4303 size_t used_bytes = hr->used(); | |
| 4304 size_t live_bytes = hr->max_live_bytes(); | |
| 4305 if (used_bytes > 0) { | |
| 4306 guarantee( live_bytes <= used_bytes, "invariant" ); | |
| 4307 } else { | |
| 4308 guarantee( live_bytes == 0, "invariant" ); | |
| 4309 } | |
| 4310 | |
| 4311 size_t garbage_bytes = used_bytes - live_bytes; | |
| 4312 if (garbage_bytes > 0) | |
| 4313 g1_policy()->decrease_known_garbage_bytes(garbage_bytes); | |
| 4314 | |
| 4315 free_region_work(hr, pre_used, cleared_h_regions, freed_regions, | |
| 4316 &local_list); | |
| 4317 finish_free_region_work(pre_used, cleared_h_regions, freed_regions, | |
| 4318 &local_list); | |
| 4319 } | |
| 4320 | |
| 4321 void | |
| 4322 G1CollectedHeap::free_region_work(HeapRegion* hr, | |
| 4323 size_t& pre_used, | |
| 4324 size_t& cleared_h_regions, | |
| 4325 size_t& freed_regions, | |
| 4326 UncleanRegionList* list, | |
| 4327 bool par) { | |
| 4328 assert(!hr->popular(), "should not free popular regions"); | |
| 4329 pre_used += hr->used(); | |
| 4330 if (hr->isHumongous()) { | |
| 4331 assert(hr->startsHumongous(), | |
| 4332 "Only the start of a humongous region should be freed."); | |
| 4333 int ind = _hrs->find(hr); | |
| 4334 assert(ind != -1, "Should have an index."); | |
| 4335 // Clear the start region. | |
| 4336 hr->hr_clear(par, true /*clear_space*/); | |
| 4337 list->insert_before_head(hr); | |
| 4338 cleared_h_regions++; | |
| 4339 freed_regions++; | |
| 4340 // Clear any continued regions. | |
| 4341 ind++; | |
| 4342 while ((size_t)ind < n_regions()) { | |
| 4343 HeapRegion* hrc = _hrs->at(ind); | |
| 4344 if (!hrc->continuesHumongous()) break; | |
| 4345 // Otherwise, does continue the H region. | |
| 4346 assert(hrc->humongous_start_region() == hr, "Huh?"); | |
| 4347 hrc->hr_clear(par, true /*clear_space*/); | |
| 4348 cleared_h_regions++; | |
| 4349 freed_regions++; | |
| 4350 list->insert_before_head(hrc); | |
| 4351 ind++; | |
| 4352 } | |
| 4353 } else { | |
| 4354 hr->hr_clear(par, true /*clear_space*/); | |
| 4355 list->insert_before_head(hr); | |
| 4356 freed_regions++; | |
| 4357 // If we're using clear2, this should not be enabled. | |
| 4358 // assert(!hr->in_cohort(), "Can't be both free and in a cohort."); | |
| 4359 } | |
| 4360 } | |
| 4361 | |
| 4362 void G1CollectedHeap::finish_free_region_work(size_t pre_used, | |
| 4363 size_t cleared_h_regions, | |
| 4364 size_t freed_regions, | |
| 4365 UncleanRegionList* list) { | |
| 4366 if (list != NULL && list->sz() > 0) { | |
| 4367 prepend_region_list_on_unclean_list(list); | |
| 4368 } | |
| 4369 // Acquire a lock, if we're parallel, to update possibly-shared | |
| 4370 // variables. | |
| 4371 Mutex* lock = (n_par_threads() > 0) ? ParGCRareEvent_lock : NULL; | |
| 4372 { | |
| 4373 MutexLockerEx x(lock, Mutex::_no_safepoint_check_flag); | |
| 4374 _summary_bytes_used -= pre_used; | |
| 4375 _num_humongous_regions -= (int) cleared_h_regions; | |
| 4376 _free_regions += freed_regions; | |
| 4377 } | |
| 4378 } | |
| 4379 | |
| 4380 | |
| 4381 void G1CollectedHeap::dirtyCardsForYoungRegions(CardTableModRefBS* ct_bs, HeapRegion* list) { | |
| 4382 while (list != NULL) { | |
| 4383 guarantee( list->is_young(), "invariant" ); | |
| 4384 | |
| 4385 HeapWord* bottom = list->bottom(); | |
| 4386 HeapWord* end = list->end(); | |
| 4387 MemRegion mr(bottom, end); | |
| 4388 ct_bs->dirty(mr); | |
| 4389 | |
| 4390 list = list->get_next_young_region(); | |
| 4391 } | |
| 4392 } | |
| 4393 | |
| 4394 void G1CollectedHeap::cleanUpCardTable() { | |
| 4395 CardTableModRefBS* ct_bs = (CardTableModRefBS*) (barrier_set()); | |
| 4396 double start = os::elapsedTime(); | |
| 4397 | |
| 4398 ct_bs->clear(_g1_committed); | |
| 4399 | |
| 4400 // now, redirty the cards of the scan-only and survivor regions | |
| 4401 // (it seemed faster to do it this way, instead of iterating over | |
| 4402 // all regions and then clearing / dirtying as approprite) | |
| 4403 dirtyCardsForYoungRegions(ct_bs, _young_list->first_scan_only_region()); | |
| 4404 dirtyCardsForYoungRegions(ct_bs, _young_list->first_survivor_region()); | |
| 4405 | |
| 4406 double elapsed = os::elapsedTime() - start; | |
| 4407 g1_policy()->record_clear_ct_time( elapsed * 1000.0); | |
| 4408 } | |
| 4409 | |
| 4410 | |
| 4411 void G1CollectedHeap::do_collection_pause_if_appropriate(size_t word_size) { | |
| 4412 // First do any popular regions. | |
| 4413 HeapRegion* hr; | |
| 4414 while ((hr = popular_region_to_evac()) != NULL) { | |
| 4415 evac_popular_region(hr); | |
| 4416 } | |
| 4417 // Now do heuristic pauses. | |
| 4418 if (g1_policy()->should_do_collection_pause(word_size)) { | |
| 4419 do_collection_pause(); | |
| 4420 } | |
| 4421 } | |
| 4422 | |
| 4423 void G1CollectedHeap::free_collection_set(HeapRegion* cs_head) { | |
| 4424 double young_time_ms = 0.0; | |
| 4425 double non_young_time_ms = 0.0; | |
| 4426 | |
| 4427 G1CollectorPolicy* policy = g1_policy(); | |
| 4428 | |
| 4429 double start_sec = os::elapsedTime(); | |
| 4430 bool non_young = true; | |
| 4431 | |
| 4432 HeapRegion* cur = cs_head; | |
| 4433 int age_bound = -1; | |
| 4434 size_t rs_lengths = 0; | |
| 4435 | |
| 4436 while (cur != NULL) { | |
| 4437 if (non_young) { | |
| 4438 if (cur->is_young()) { | |
| 4439 double end_sec = os::elapsedTime(); | |
| 4440 double elapsed_ms = (end_sec - start_sec) * 1000.0; | |
| 4441 non_young_time_ms += elapsed_ms; | |
| 4442 | |
| 4443 start_sec = os::elapsedTime(); | |
| 4444 non_young = false; | |
| 4445 } | |
| 4446 } else { | |
| 4447 if (!cur->is_on_free_list()) { | |
| 4448 double end_sec = os::elapsedTime(); | |
| 4449 double elapsed_ms = (end_sec - start_sec) * 1000.0; | |
| 4450 young_time_ms += elapsed_ms; | |
| 4451 | |
| 4452 start_sec = os::elapsedTime(); | |
| 4453 non_young = true; | |
| 4454 } | |
| 4455 } | |
| 4456 | |
| 4457 rs_lengths += cur->rem_set()->occupied(); | |
| 4458 | |
| 4459 HeapRegion* next = cur->next_in_collection_set(); | |
| 4460 assert(cur->in_collection_set(), "bad CS"); | |
| 4461 cur->set_next_in_collection_set(NULL); | |
| 4462 cur->set_in_collection_set(false); | |
| 4463 | |
| 4464 if (cur->is_young()) { | |
| 4465 int index = cur->young_index_in_cset(); | |
| 4466 guarantee( index != -1, "invariant" ); | |
| 4467 guarantee( (size_t)index < policy->young_cset_length(), "invariant" ); | |
| 4468 size_t words_survived = _surviving_young_words[index]; | |
| 4469 cur->record_surv_words_in_group(words_survived); | |
| 4470 } else { | |
| 4471 int index = cur->young_index_in_cset(); | |
| 4472 guarantee( index == -1, "invariant" ); | |
| 4473 } | |
| 4474 | |
| 4475 assert( (cur->is_young() && cur->young_index_in_cset() > -1) || | |
| 4476 (!cur->is_young() && cur->young_index_in_cset() == -1), | |
| 4477 "invariant" ); | |
| 4478 | |
| 4479 if (!cur->evacuation_failed()) { | |
| 4480 // And the region is empty. | |
| 4481 assert(!cur->is_empty(), | |
| 4482 "Should not have empty regions in a CS."); | |
| 4483 free_region(cur); | |
| 4484 } else { | |
| 4485 guarantee( !cur->is_scan_only(), "should not be scan only" ); | |
| 4486 cur->uninstall_surv_rate_group(); | |
| 4487 if (cur->is_young()) | |
| 4488 cur->set_young_index_in_cset(-1); | |
| 4489 cur->set_not_young(); | |
| 4490 cur->set_evacuation_failed(false); | |
| 4491 } | |
| 4492 cur = next; | |
| 4493 } | |
| 4494 | |
| 4495 policy->record_max_rs_lengths(rs_lengths); | |
| 4496 policy->cset_regions_freed(); | |
| 4497 | |
| 4498 double end_sec = os::elapsedTime(); | |
| 4499 double elapsed_ms = (end_sec - start_sec) * 1000.0; | |
| 4500 if (non_young) | |
| 4501 non_young_time_ms += elapsed_ms; | |
| 4502 else | |
| 4503 young_time_ms += elapsed_ms; | |
| 4504 | |
| 4505 policy->record_young_free_cset_time_ms(young_time_ms); | |
| 4506 policy->record_non_young_free_cset_time_ms(non_young_time_ms); | |
| 4507 } | |
| 4508 | |
| 4509 HeapRegion* | |
| 4510 G1CollectedHeap::alloc_region_from_unclean_list_locked(bool zero_filled) { | |
| 4511 assert(ZF_mon->owned_by_self(), "Precondition"); | |
| 4512 HeapRegion* res = pop_unclean_region_list_locked(); | |
| 4513 if (res != NULL) { | |
| 4514 assert(!res->continuesHumongous() && | |
| 4515 res->zero_fill_state() != HeapRegion::Allocated, | |
| 4516 "Only free regions on unclean list."); | |
| 4517 if (zero_filled) { | |
| 4518 res->ensure_zero_filled_locked(); | |
| 4519 res->set_zero_fill_allocated(); | |
| 4520 } | |
| 4521 } | |
| 4522 return res; | |
| 4523 } | |
| 4524 | |
| 4525 HeapRegion* G1CollectedHeap::alloc_region_from_unclean_list(bool zero_filled) { | |
| 4526 MutexLockerEx zx(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 4527 return alloc_region_from_unclean_list_locked(zero_filled); | |
| 4528 } | |
| 4529 | |
| 4530 void G1CollectedHeap::put_region_on_unclean_list(HeapRegion* r) { | |
| 4531 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 4532 put_region_on_unclean_list_locked(r); | |
| 4533 if (should_zf()) ZF_mon->notify_all(); // Wake up ZF thread. | |
| 4534 } | |
| 4535 | |
| 4536 void G1CollectedHeap::set_unclean_regions_coming(bool b) { | |
| 4537 MutexLockerEx x(Cleanup_mon); | |
| 4538 set_unclean_regions_coming_locked(b); | |
| 4539 } | |
| 4540 | |
| 4541 void G1CollectedHeap::set_unclean_regions_coming_locked(bool b) { | |
| 4542 assert(Cleanup_mon->owned_by_self(), "Precondition"); | |
| 4543 _unclean_regions_coming = b; | |
| 4544 // Wake up mutator threads that might be waiting for completeCleanup to | |
| 4545 // finish. | |
| 4546 if (!b) Cleanup_mon->notify_all(); | |
| 4547 } | |
| 4548 | |
| 4549 void G1CollectedHeap::wait_for_cleanup_complete() { | |
| 4550 MutexLockerEx x(Cleanup_mon); | |
| 4551 wait_for_cleanup_complete_locked(); | |
| 4552 } | |
| 4553 | |
| 4554 void G1CollectedHeap::wait_for_cleanup_complete_locked() { | |
| 4555 assert(Cleanup_mon->owned_by_self(), "precondition"); | |
| 4556 while (_unclean_regions_coming) { | |
| 4557 Cleanup_mon->wait(); | |
| 4558 } | |
| 4559 } | |
| 4560 | |
| 4561 void | |
| 4562 G1CollectedHeap::put_region_on_unclean_list_locked(HeapRegion* r) { | |
| 4563 assert(ZF_mon->owned_by_self(), "precondition."); | |
| 4564 _unclean_region_list.insert_before_head(r); | |
| 4565 } | |
| 4566 | |
| 4567 void | |
| 4568 G1CollectedHeap::prepend_region_list_on_unclean_list(UncleanRegionList* list) { | |
| 4569 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 4570 prepend_region_list_on_unclean_list_locked(list); | |
| 4571 if (should_zf()) ZF_mon->notify_all(); // Wake up ZF thread. | |
| 4572 } | |
| 4573 | |
| 4574 void | |
| 4575 G1CollectedHeap:: | |
| 4576 prepend_region_list_on_unclean_list_locked(UncleanRegionList* list) { | |
| 4577 assert(ZF_mon->owned_by_self(), "precondition."); | |
| 4578 _unclean_region_list.prepend_list(list); | |
| 4579 } | |
| 4580 | |
| 4581 HeapRegion* G1CollectedHeap::pop_unclean_region_list_locked() { | |
| 4582 assert(ZF_mon->owned_by_self(), "precondition."); | |
| 4583 HeapRegion* res = _unclean_region_list.pop(); | |
| 4584 if (res != NULL) { | |
| 4585 // Inform ZF thread that there's a new unclean head. | |
| 4586 if (_unclean_region_list.hd() != NULL && should_zf()) | |
| 4587 ZF_mon->notify_all(); | |
| 4588 } | |
| 4589 return res; | |
| 4590 } | |
| 4591 | |
| 4592 HeapRegion* G1CollectedHeap::peek_unclean_region_list_locked() { | |
| 4593 assert(ZF_mon->owned_by_self(), "precondition."); | |
| 4594 return _unclean_region_list.hd(); | |
| 4595 } | |
| 4596 | |
| 4597 | |
| 4598 bool G1CollectedHeap::move_cleaned_region_to_free_list_locked() { | |
| 4599 assert(ZF_mon->owned_by_self(), "Precondition"); | |
| 4600 HeapRegion* r = peek_unclean_region_list_locked(); | |
| 4601 if (r != NULL && r->zero_fill_state() == HeapRegion::ZeroFilled) { | |
| 4602 // Result of below must be equal to "r", since we hold the lock. | |
| 4603 (void)pop_unclean_region_list_locked(); | |
| 4604 put_free_region_on_list_locked(r); | |
| 4605 return true; | |
| 4606 } else { | |
| 4607 return false; | |
| 4608 } | |
| 4609 } | |
| 4610 | |
| 4611 bool G1CollectedHeap::move_cleaned_region_to_free_list() { | |
| 4612 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 4613 return move_cleaned_region_to_free_list_locked(); | |
| 4614 } | |
| 4615 | |
| 4616 | |
| 4617 void G1CollectedHeap::put_free_region_on_list_locked(HeapRegion* r) { | |
| 4618 assert(ZF_mon->owned_by_self(), "precondition."); | |
| 4619 assert(_free_region_list_size == free_region_list_length(), "Inv"); | |
| 4620 assert(r->zero_fill_state() == HeapRegion::ZeroFilled, | |
| 4621 "Regions on free list must be zero filled"); | |
| 4622 assert(!r->isHumongous(), "Must not be humongous."); | |
| 4623 assert(r->is_empty(), "Better be empty"); | |
| 4624 assert(!r->is_on_free_list(), | |
| 4625 "Better not already be on free list"); | |
| 4626 assert(!r->is_on_unclean_list(), | |
| 4627 "Better not already be on unclean list"); | |
| 4628 r->set_on_free_list(true); | |
| 4629 r->set_next_on_free_list(_free_region_list); | |
| 4630 _free_region_list = r; | |
| 4631 _free_region_list_size++; | |
| 4632 assert(_free_region_list_size == free_region_list_length(), "Inv"); | |
| 4633 } | |
| 4634 | |
| 4635 void G1CollectedHeap::put_free_region_on_list(HeapRegion* r) { | |
| 4636 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 4637 put_free_region_on_list_locked(r); | |
| 4638 } | |
| 4639 | |
| 4640 HeapRegion* G1CollectedHeap::pop_free_region_list_locked() { | |
| 4641 assert(ZF_mon->owned_by_self(), "precondition."); | |
| 4642 assert(_free_region_list_size == free_region_list_length(), "Inv"); | |
| 4643 HeapRegion* res = _free_region_list; | |
| 4644 if (res != NULL) { | |
| 4645 _free_region_list = res->next_from_free_list(); | |
| 4646 _free_region_list_size--; | |
| 4647 res->set_on_free_list(false); | |
| 4648 res->set_next_on_free_list(NULL); | |
| 4649 assert(_free_region_list_size == free_region_list_length(), "Inv"); | |
| 4650 } | |
| 4651 return res; | |
| 4652 } | |
| 4653 | |
| 4654 | |
| 4655 HeapRegion* G1CollectedHeap::alloc_free_region_from_lists(bool zero_filled) { | |
| 4656 // By self, or on behalf of self. | |
| 4657 assert(Heap_lock->is_locked(), "Precondition"); | |
| 4658 HeapRegion* res = NULL; | |
| 4659 bool first = true; | |
| 4660 while (res == NULL) { | |
| 4661 if (zero_filled || !first) { | |
| 4662 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 4663 res = pop_free_region_list_locked(); | |
| 4664 if (res != NULL) { | |
| 4665 assert(!res->zero_fill_is_allocated(), | |
| 4666 "No allocated regions on free list."); | |
| 4667 res->set_zero_fill_allocated(); | |
| 4668 } else if (!first) { | |
| 4669 break; // We tried both, time to return NULL. | |
| 4670 } | |
| 4671 } | |
| 4672 | |
| 4673 if (res == NULL) { | |
| 4674 res = alloc_region_from_unclean_list(zero_filled); | |
| 4675 } | |
| 4676 assert(res == NULL || | |
| 4677 !zero_filled || | |
| 4678 res->zero_fill_is_allocated(), | |
| 4679 "We must have allocated the region we're returning"); | |
| 4680 first = false; | |
| 4681 } | |
| 4682 return res; | |
| 4683 } | |
| 4684 | |
| 4685 void G1CollectedHeap::remove_allocated_regions_from_lists() { | |
| 4686 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 4687 { | |
| 4688 HeapRegion* prev = NULL; | |
| 4689 HeapRegion* cur = _unclean_region_list.hd(); | |
| 4690 while (cur != NULL) { | |
| 4691 HeapRegion* next = cur->next_from_unclean_list(); | |
| 4692 if (cur->zero_fill_is_allocated()) { | |
| 4693 // Remove from the list. | |
| 4694 if (prev == NULL) { | |
| 4695 (void)_unclean_region_list.pop(); | |
| 4696 } else { | |
| 4697 _unclean_region_list.delete_after(prev); | |
| 4698 } | |
| 4699 cur->set_on_unclean_list(false); | |
| 4700 cur->set_next_on_unclean_list(NULL); | |
| 4701 } else { | |
| 4702 prev = cur; | |
| 4703 } | |
| 4704 cur = next; | |
| 4705 } | |
| 4706 assert(_unclean_region_list.sz() == unclean_region_list_length(), | |
| 4707 "Inv"); | |
| 4708 } | |
| 4709 | |
| 4710 { | |
| 4711 HeapRegion* prev = NULL; | |
| 4712 HeapRegion* cur = _free_region_list; | |
| 4713 while (cur != NULL) { | |
| 4714 HeapRegion* next = cur->next_from_free_list(); | |
| 4715 if (cur->zero_fill_is_allocated()) { | |
| 4716 // Remove from the list. | |
| 4717 if (prev == NULL) { | |
| 4718 _free_region_list = cur->next_from_free_list(); | |
| 4719 } else { | |
| 4720 prev->set_next_on_free_list(cur->next_from_free_list()); | |
| 4721 } | |
| 4722 cur->set_on_free_list(false); | |
| 4723 cur->set_next_on_free_list(NULL); | |
| 4724 _free_region_list_size--; | |
| 4725 } else { | |
| 4726 prev = cur; | |
| 4727 } | |
| 4728 cur = next; | |
| 4729 } | |
| 4730 assert(_free_region_list_size == free_region_list_length(), "Inv"); | |
| 4731 } | |
| 4732 } | |
| 4733 | |
| 4734 bool G1CollectedHeap::verify_region_lists() { | |
| 4735 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 4736 return verify_region_lists_locked(); | |
| 4737 } | |
| 4738 | |
| 4739 bool G1CollectedHeap::verify_region_lists_locked() { | |
| 4740 HeapRegion* unclean = _unclean_region_list.hd(); | |
| 4741 while (unclean != NULL) { | |
| 4742 guarantee(unclean->is_on_unclean_list(), "Well, it is!"); | |
| 4743 guarantee(!unclean->is_on_free_list(), "Well, it shouldn't be!"); | |
| 4744 guarantee(unclean->zero_fill_state() != HeapRegion::Allocated, | |
| 4745 "Everything else is possible."); | |
| 4746 unclean = unclean->next_from_unclean_list(); | |
| 4747 } | |
| 4748 guarantee(_unclean_region_list.sz() == unclean_region_list_length(), "Inv"); | |
| 4749 | |
| 4750 HeapRegion* free_r = _free_region_list; | |
| 4751 while (free_r != NULL) { | |
| 4752 assert(free_r->is_on_free_list(), "Well, it is!"); | |
| 4753 assert(!free_r->is_on_unclean_list(), "Well, it shouldn't be!"); | |
| 4754 switch (free_r->zero_fill_state()) { | |
| 4755 case HeapRegion::NotZeroFilled: | |
| 4756 case HeapRegion::ZeroFilling: | |
| 4757 guarantee(false, "Should not be on free list."); | |
| 4758 break; | |
| 4759 default: | |
| 4760 // Everything else is possible. | |
| 4761 break; | |
| 4762 } | |
| 4763 free_r = free_r->next_from_free_list(); | |
| 4764 } | |
| 4765 guarantee(_free_region_list_size == free_region_list_length(), "Inv"); | |
| 4766 // If we didn't do an assertion... | |
| 4767 return true; | |
| 4768 } | |
| 4769 | |
| 4770 size_t G1CollectedHeap::free_region_list_length() { | |
| 4771 assert(ZF_mon->owned_by_self(), "precondition."); | |
| 4772 size_t len = 0; | |
| 4773 HeapRegion* cur = _free_region_list; | |
| 4774 while (cur != NULL) { | |
| 4775 len++; | |
| 4776 cur = cur->next_from_free_list(); | |
| 4777 } | |
| 4778 return len; | |
| 4779 } | |
| 4780 | |
| 4781 size_t G1CollectedHeap::unclean_region_list_length() { | |
| 4782 assert(ZF_mon->owned_by_self(), "precondition."); | |
| 4783 return _unclean_region_list.length(); | |
| 4784 } | |
| 4785 | |
| 4786 size_t G1CollectedHeap::n_regions() { | |
| 4787 return _hrs->length(); | |
| 4788 } | |
| 4789 | |
| 4790 size_t G1CollectedHeap::max_regions() { | |
| 4791 return | |
| 4792 (size_t)align_size_up(g1_reserved_obj_bytes(), HeapRegion::GrainBytes) / | |
| 4793 HeapRegion::GrainBytes; | |
| 4794 } | |
| 4795 | |
| 4796 size_t G1CollectedHeap::free_regions() { | |
| 4797 /* Possibly-expensive assert. | |
| 4798 assert(_free_regions == count_free_regions(), | |
| 4799 "_free_regions is off."); | |
| 4800 */ | |
| 4801 return _free_regions; | |
| 4802 } | |
| 4803 | |
| 4804 bool G1CollectedHeap::should_zf() { | |
| 4805 return _free_region_list_size < (size_t) G1ConcZFMaxRegions; | |
| 4806 } | |
| 4807 | |
| 4808 class RegionCounter: public HeapRegionClosure { | |
| 4809 size_t _n; | |
| 4810 public: | |
| 4811 RegionCounter() : _n(0) {} | |
| 4812 bool doHeapRegion(HeapRegion* r) { | |
| 4813 if (r->is_empty() && !r->popular()) { | |
| 4814 assert(!r->isHumongous(), "H regions should not be empty."); | |
| 4815 _n++; | |
| 4816 } | |
| 4817 return false; | |
| 4818 } | |
| 4819 int res() { return (int) _n; } | |
| 4820 }; | |
| 4821 | |
| 4822 size_t G1CollectedHeap::count_free_regions() { | |
| 4823 RegionCounter rc; | |
| 4824 heap_region_iterate(&rc); | |
| 4825 size_t n = rc.res(); | |
| 4826 if (_cur_alloc_region != NULL && _cur_alloc_region->is_empty()) | |
| 4827 n--; | |
| 4828 return n; | |
| 4829 } | |
| 4830 | |
| 4831 size_t G1CollectedHeap::count_free_regions_list() { | |
| 4832 size_t n = 0; | |
| 4833 size_t o = 0; | |
| 4834 ZF_mon->lock_without_safepoint_check(); | |
| 4835 HeapRegion* cur = _free_region_list; | |
| 4836 while (cur != NULL) { | |
| 4837 cur = cur->next_from_free_list(); | |
| 4838 n++; | |
| 4839 } | |
| 4840 size_t m = unclean_region_list_length(); | |
| 4841 ZF_mon->unlock(); | |
| 4842 return n + m; | |
| 4843 } | |
| 4844 | |
| 4845 bool G1CollectedHeap::should_set_young_locked() { | |
| 4846 assert(heap_lock_held_for_gc(), | |
| 4847 "the heap lock should already be held by or for this thread"); | |
| 4848 return (g1_policy()->in_young_gc_mode() && | |
| 4849 g1_policy()->should_add_next_region_to_young_list()); | |
| 4850 } | |
| 4851 | |
| 4852 void G1CollectedHeap::set_region_short_lived_locked(HeapRegion* hr) { | |
| 4853 assert(heap_lock_held_for_gc(), | |
| 4854 "the heap lock should already be held by or for this thread"); | |
| 4855 _young_list->push_region(hr); | |
| 4856 g1_policy()->set_region_short_lived(hr); | |
| 4857 } | |
| 4858 | |
| 4859 class NoYoungRegionsClosure: public HeapRegionClosure { | |
| 4860 private: | |
| 4861 bool _success; | |
| 4862 public: | |
| 4863 NoYoungRegionsClosure() : _success(true) { } | |
| 4864 bool doHeapRegion(HeapRegion* r) { | |
| 4865 if (r->is_young()) { | |
| 4866 gclog_or_tty->print_cr("Region ["PTR_FORMAT", "PTR_FORMAT") tagged as young", | |
| 4867 r->bottom(), r->end()); | |
| 4868 _success = false; | |
| 4869 } | |
| 4870 return false; | |
| 4871 } | |
| 4872 bool success() { return _success; } | |
| 4873 }; | |
| 4874 | |
| 4875 bool G1CollectedHeap::check_young_list_empty(bool ignore_scan_only_list, | |
| 4876 bool check_sample) { | |
| 4877 bool ret = true; | |
| 4878 | |
| 4879 ret = _young_list->check_list_empty(ignore_scan_only_list, check_sample); | |
| 4880 if (!ignore_scan_only_list) { | |
| 4881 NoYoungRegionsClosure closure; | |
| 4882 heap_region_iterate(&closure); | |
| 4883 ret = ret && closure.success(); | |
| 4884 } | |
| 4885 | |
| 4886 return ret; | |
| 4887 } | |
| 4888 | |
| 4889 void G1CollectedHeap::empty_young_list() { | |
| 4890 assert(heap_lock_held_for_gc(), | |
| 4891 "the heap lock should already be held by or for this thread"); | |
| 4892 assert(g1_policy()->in_young_gc_mode(), "should be in young GC mode"); | |
| 4893 | |
| 4894 _young_list->empty_list(); | |
| 4895 } | |
| 4896 | |
| 4897 bool G1CollectedHeap::all_alloc_regions_no_allocs_since_save_marks() { | |
| 4898 bool no_allocs = true; | |
| 4899 for (int ap = 0; ap < GCAllocPurposeCount && no_allocs; ++ap) { | |
| 4900 HeapRegion* r = _gc_alloc_regions[ap]; | |
| 4901 no_allocs = r == NULL || r->saved_mark_at_top(); | |
| 4902 } | |
| 4903 return no_allocs; | |
| 4904 } | |
| 4905 | |
| 4906 void G1CollectedHeap::all_alloc_regions_note_end_of_copying() { | |
| 4907 for (int ap = 0; ap < GCAllocPurposeCount; ++ap) { | |
| 4908 HeapRegion* r = _gc_alloc_regions[ap]; | |
| 4909 if (r != NULL) { | |
| 4910 // Check for aliases. | |
| 4911 bool has_processed_alias = false; | |
| 4912 for (int i = 0; i < ap; ++i) { | |
| 4913 if (_gc_alloc_regions[i] == r) { | |
| 4914 has_processed_alias = true; | |
| 4915 break; | |
| 4916 } | |
| 4917 } | |
| 4918 if (!has_processed_alias) { | |
| 4919 r->note_end_of_copying(); | |
| 4920 g1_policy()->record_after_bytes(r->used()); | |
| 4921 } | |
| 4922 } | |
| 4923 } | |
| 4924 } | |
| 4925 | |
| 4926 | |
| 4927 // Done at the start of full GC. | |
| 4928 void G1CollectedHeap::tear_down_region_lists() { | |
| 4929 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 4930 while (pop_unclean_region_list_locked() != NULL) ; | |
| 4931 assert(_unclean_region_list.hd() == NULL && _unclean_region_list.sz() == 0, | |
| 4932 "Postconditions of loop.") | |
| 4933 while (pop_free_region_list_locked() != NULL) ; | |
| 4934 assert(_free_region_list == NULL, "Postcondition of loop."); | |
| 4935 if (_free_region_list_size != 0) { | |
| 4936 gclog_or_tty->print_cr("Size is %d.", _free_region_list_size); | |
| 4937 print(); | |
| 4938 } | |
| 4939 assert(_free_region_list_size == 0, "Postconditions of loop."); | |
| 4940 } | |
| 4941 | |
| 4942 | |
| 4943 class RegionResetter: public HeapRegionClosure { | |
| 4944 G1CollectedHeap* _g1; | |
| 4945 int _n; | |
| 4946 public: | |
| 4947 RegionResetter() : _g1(G1CollectedHeap::heap()), _n(0) {} | |
| 4948 bool doHeapRegion(HeapRegion* r) { | |
| 4949 if (r->continuesHumongous()) return false; | |
| 4950 if (r->top() > r->bottom()) { | |
| 4951 if (r->top() < r->end()) { | |
| 4952 Copy::fill_to_words(r->top(), | |
| 4953 pointer_delta(r->end(), r->top())); | |
| 4954 } | |
| 4955 r->set_zero_fill_allocated(); | |
| 4956 } else { | |
| 4957 assert(r->is_empty(), "tautology"); | |
| 4958 if (r->popular()) { | |
| 4959 if (r->zero_fill_state() != HeapRegion::Allocated) { | |
| 4960 r->ensure_zero_filled_locked(); | |
| 4961 r->set_zero_fill_allocated(); | |
| 4962 } | |
| 4963 } else { | |
| 4964 _n++; | |
| 4965 switch (r->zero_fill_state()) { | |
| 4966 case HeapRegion::NotZeroFilled: | |
| 4967 case HeapRegion::ZeroFilling: | |
| 4968 _g1->put_region_on_unclean_list_locked(r); | |
| 4969 break; | |
| 4970 case HeapRegion::Allocated: | |
| 4971 r->set_zero_fill_complete(); | |
| 4972 // no break; go on to put on free list. | |
| 4973 case HeapRegion::ZeroFilled: | |
| 4974 _g1->put_free_region_on_list_locked(r); | |
| 4975 break; | |
| 4976 } | |
| 4977 } | |
| 4978 } | |
| 4979 return false; | |
| 4980 } | |
| 4981 | |
| 4982 int getFreeRegionCount() {return _n;} | |
| 4983 }; | |
| 4984 | |
| 4985 // Done at the end of full GC. | |
| 4986 void G1CollectedHeap::rebuild_region_lists() { | |
| 4987 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 4988 // This needs to go at the end of the full GC. | |
| 4989 RegionResetter rs; | |
| 4990 heap_region_iterate(&rs); | |
| 4991 _free_regions = rs.getFreeRegionCount(); | |
| 4992 // Tell the ZF thread it may have work to do. | |
| 4993 if (should_zf()) ZF_mon->notify_all(); | |
| 4994 } | |
| 4995 | |
| 4996 class UsedRegionsNeedZeroFillSetter: public HeapRegionClosure { | |
| 4997 G1CollectedHeap* _g1; | |
| 4998 int _n; | |
| 4999 public: | |
| 5000 UsedRegionsNeedZeroFillSetter() : _g1(G1CollectedHeap::heap()), _n(0) {} | |
| 5001 bool doHeapRegion(HeapRegion* r) { | |
| 5002 if (r->continuesHumongous()) return false; | |
| 5003 if (r->top() > r->bottom()) { | |
| 5004 // There are assertions in "set_zero_fill_needed()" below that | |
| 5005 // require top() == bottom(), so this is technically illegal. | |
| 5006 // We'll skirt the law here, by making that true temporarily. | |
| 5007 DEBUG_ONLY(HeapWord* save_top = r->top(); | |
| 5008 r->set_top(r->bottom())); | |
| 5009 r->set_zero_fill_needed(); | |
| 5010 DEBUG_ONLY(r->set_top(save_top)); | |
| 5011 } | |
| 5012 return false; | |
| 5013 } | |
| 5014 }; | |
| 5015 | |
| 5016 // Done at the start of full GC. | |
| 5017 void G1CollectedHeap::set_used_regions_to_need_zero_fill() { | |
| 5018 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); | |
| 5019 // This needs to go at the end of the full GC. | |
| 5020 UsedRegionsNeedZeroFillSetter rs; | |
| 5021 heap_region_iterate(&rs); | |
| 5022 } | |
| 5023 | |
| 5024 class CountObjClosure: public ObjectClosure { | |
| 5025 size_t _n; | |
| 5026 public: | |
| 5027 CountObjClosure() : _n(0) {} | |
| 5028 void do_object(oop obj) { _n++; } | |
| 5029 size_t n() { return _n; } | |
| 5030 }; | |
| 5031 | |
| 5032 size_t G1CollectedHeap::pop_object_used_objs() { | |
| 5033 size_t sum_objs = 0; | |
| 5034 for (int i = 0; i < G1NumPopularRegions; i++) { | |
| 5035 CountObjClosure cl; | |
| 5036 _hrs->at(i)->object_iterate(&cl); | |
| 5037 sum_objs += cl.n(); | |
| 5038 } | |
| 5039 return sum_objs; | |
| 5040 } | |
| 5041 | |
| 5042 size_t G1CollectedHeap::pop_object_used_bytes() { | |
| 5043 size_t sum_bytes = 0; | |
| 5044 for (int i = 0; i < G1NumPopularRegions; i++) { | |
| 5045 sum_bytes += _hrs->at(i)->used(); | |
| 5046 } | |
| 5047 return sum_bytes; | |
| 5048 } | |
| 5049 | |
| 5050 | |
| 5051 static int nq = 0; | |
| 5052 | |
| 5053 HeapWord* G1CollectedHeap::allocate_popular_object(size_t word_size) { | |
| 5054 while (_cur_pop_hr_index < G1NumPopularRegions) { | |
| 5055 HeapRegion* cur_pop_region = _hrs->at(_cur_pop_hr_index); | |
| 5056 HeapWord* res = cur_pop_region->allocate(word_size); | |
| 5057 if (res != NULL) { | |
| 5058 // We account for popular objs directly in the used summary: | |
| 5059 _summary_bytes_used += (word_size * HeapWordSize); | |
| 5060 return res; | |
| 5061 } | |
| 5062 // Otherwise, try the next region (first making sure that we remember | |
| 5063 // the last "top" value as the "next_top_at_mark_start", so that | |
| 5064 // objects made popular during markings aren't automatically considered | |
| 5065 // live). | |
| 5066 cur_pop_region->note_end_of_copying(); | |
| 5067 // Otherwise, try the next region. | |
| 5068 _cur_pop_hr_index++; | |
| 5069 } | |
| 5070 // XXX: For now !!! | |
| 5071 vm_exit_out_of_memory(word_size, | |
| 5072 "Not enough pop obj space (To Be Fixed)"); | |
| 5073 return NULL; | |
| 5074 } | |
| 5075 | |
| 5076 class HeapRegionList: public CHeapObj { | |
| 5077 public: | |
| 5078 HeapRegion* hr; | |
| 5079 HeapRegionList* next; | |
| 5080 }; | |
| 5081 | |
| 5082 void G1CollectedHeap::schedule_popular_region_evac(HeapRegion* r) { | |
| 5083 // This might happen during parallel GC, so protect by this lock. | |
| 5084 MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag); | |
| 5085 // We don't schedule regions whose evacuations are already pending, or | |
| 5086 // are already being evacuated. | |
| 5087 if (!r->popular_pending() && !r->in_collection_set()) { | |
| 5088 r->set_popular_pending(true); | |
| 5089 if (G1TracePopularity) { | |
| 5090 gclog_or_tty->print_cr("Scheduling region "PTR_FORMAT" " | |
| 5091 "["PTR_FORMAT", "PTR_FORMAT") for pop-object evacuation.", | |
| 5092 r, r->bottom(), r->end()); | |
| 5093 } | |
| 5094 HeapRegionList* hrl = new HeapRegionList; | |
| 5095 hrl->hr = r; | |
| 5096 hrl->next = _popular_regions_to_be_evacuated; | |
| 5097 _popular_regions_to_be_evacuated = hrl; | |
| 5098 } | |
| 5099 } | |
| 5100 | |
| 5101 HeapRegion* G1CollectedHeap::popular_region_to_evac() { | |
| 5102 MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag); | |
| 5103 HeapRegion* res = NULL; | |
| 5104 while (_popular_regions_to_be_evacuated != NULL && res == NULL) { | |
| 5105 HeapRegionList* hrl = _popular_regions_to_be_evacuated; | |
| 5106 _popular_regions_to_be_evacuated = hrl->next; | |
| 5107 res = hrl->hr; | |
| 5108 // The G1RSPopLimit may have increased, so recheck here... | |
| 5109 if (res->rem_set()->occupied() < (size_t) G1RSPopLimit) { | |
| 5110 // Hah: don't need to schedule. | |
| 5111 if (G1TracePopularity) { | |
| 5112 gclog_or_tty->print_cr("Unscheduling region "PTR_FORMAT" " | |
| 5113 "["PTR_FORMAT", "PTR_FORMAT") " | |
| 5114 "for pop-object evacuation (size %d < limit %d)", | |
| 5115 res, res->bottom(), res->end(), | |
| 5116 res->rem_set()->occupied(), G1RSPopLimit); | |
| 5117 } | |
| 5118 res->set_popular_pending(false); | |
| 5119 res = NULL; | |
| 5120 } | |
| 5121 // We do not reset res->popular() here; if we did so, it would allow | |
| 5122 // the region to be "rescheduled" for popularity evacuation. Instead, | |
| 5123 // this is done in the collection pause, with the world stopped. | |
| 5124 // So the invariant is that the regions in the list have the popularity | |
| 5125 // boolean set, but having the boolean set does not imply membership | |
| 5126 // on the list (though there can at most one such pop-pending region | |
| 5127 // not on the list at any time). | |
| 5128 delete hrl; | |
| 5129 } | |
| 5130 return res; | |
| 5131 } | |
| 5132 | |
| 5133 void G1CollectedHeap::evac_popular_region(HeapRegion* hr) { | |
| 5134 while (true) { | |
| 5135 // Don't want to do a GC pause while cleanup is being completed! | |
| 5136 wait_for_cleanup_complete(); | |
| 5137 | |
| 5138 // Read the GC count while holding the Heap_lock | |
| 5139 int gc_count_before = SharedHeap::heap()->total_collections(); | |
| 5140 g1_policy()->record_stop_world_start(); | |
| 5141 | |
| 5142 { | |
| 5143 MutexUnlocker mu(Heap_lock); // give up heap lock, execute gets it back | |
| 5144 VM_G1PopRegionCollectionPause op(gc_count_before, hr); | |
| 5145 VMThread::execute(&op); | |
| 5146 | |
| 5147 // If the prolog succeeded, we didn't do a GC for this. | |
| 5148 if (op.prologue_succeeded()) break; | |
| 5149 } | |
| 5150 // Otherwise we didn't. We should recheck the size, though, since | |
| 5151 // the limit may have increased... | |
| 5152 if (hr->rem_set()->occupied() < (size_t) G1RSPopLimit) { | |
| 5153 hr->set_popular_pending(false); | |
| 5154 break; | |
| 5155 } | |
| 5156 } | |
| 5157 } | |
| 5158 | |
| 5159 void G1CollectedHeap::atomic_inc_obj_rc(oop obj) { | |
| 5160 Atomic::inc(obj_rc_addr(obj)); | |
| 5161 } | |
| 5162 | |
| 5163 class CountRCClosure: public OopsInHeapRegionClosure { | |
| 5164 G1CollectedHeap* _g1h; | |
| 5165 bool _parallel; | |
| 5166 public: | |
| 5167 CountRCClosure(G1CollectedHeap* g1h) : | |
| 5168 _g1h(g1h), _parallel(ParallelGCThreads > 0) | |
| 5169 {} | |
| 5170 void do_oop(narrowOop* p) { | |
| 5171 guarantee(false, "NYI"); | |
| 5172 } | |
| 5173 void do_oop(oop* p) { | |
| 5174 oop obj = *p; | |
| 5175 assert(obj != NULL, "Precondition."); | |
| 5176 if (_parallel) { | |
| 5177 // We go sticky at the limit to avoid excess contention. | |
| 5178 // If we want to track the actual RC's further, we'll need to keep a | |
| 5179 // per-thread hash table or something for the popular objects. | |
| 5180 if (_g1h->obj_rc(obj) < G1ObjPopLimit) { | |
| 5181 _g1h->atomic_inc_obj_rc(obj); | |
| 5182 } | |
| 5183 } else { | |
| 5184 _g1h->inc_obj_rc(obj); | |
| 5185 } | |
| 5186 } | |
| 5187 }; | |
| 5188 | |
| 5189 class EvacPopObjClosure: public ObjectClosure { | |
| 5190 G1CollectedHeap* _g1h; | |
| 5191 size_t _pop_objs; | |
| 5192 size_t _max_rc; | |
| 5193 public: | |
| 5194 EvacPopObjClosure(G1CollectedHeap* g1h) : | |
| 5195 _g1h(g1h), _pop_objs(0), _max_rc(0) {} | |
| 5196 | |
| 5197 void do_object(oop obj) { | |
| 5198 size_t rc = _g1h->obj_rc(obj); | |
| 5199 _max_rc = MAX2(rc, _max_rc); | |
| 5200 if (rc >= (size_t) G1ObjPopLimit) { | |
| 5201 _g1h->_pop_obj_rc_at_copy.add((double)rc); | |
| 5202 size_t word_sz = obj->size(); | |
| 5203 HeapWord* new_pop_loc = _g1h->allocate_popular_object(word_sz); | |
| 5204 oop new_pop_obj = (oop)new_pop_loc; | |
| 5205 Copy::aligned_disjoint_words((HeapWord*)obj, new_pop_loc, word_sz); | |
| 5206 obj->forward_to(new_pop_obj); | |
| 5207 G1ScanAndBalanceClosure scan_and_balance(_g1h); | |
| 5208 new_pop_obj->oop_iterate_backwards(&scan_and_balance); | |
| 5209 // preserve "next" mark bit if marking is in progress. | |
| 5210 if (_g1h->mark_in_progress() && !_g1h->is_obj_ill(obj)) { | |
| 5211 _g1h->concurrent_mark()->markAndGrayObjectIfNecessary(new_pop_obj); | |
| 5212 } | |
| 5213 | |
| 5214 if (G1TracePopularity) { | |
| 5215 gclog_or_tty->print_cr("Found obj " PTR_FORMAT " of word size " SIZE_FORMAT | |
| 5216 " pop (%d), move to " PTR_FORMAT, | |
| 5217 (void*) obj, word_sz, | |
| 5218 _g1h->obj_rc(obj), (void*) new_pop_obj); | |
| 5219 } | |
| 5220 _pop_objs++; | |
| 5221 } | |
| 5222 } | |
| 5223 size_t pop_objs() { return _pop_objs; } | |
| 5224 size_t max_rc() { return _max_rc; } | |
| 5225 }; | |
| 5226 | |
| 5227 class G1ParCountRCTask : public AbstractGangTask { | |
| 5228 G1CollectedHeap* _g1h; | |
| 5229 BitMap _bm; | |
| 5230 | |
| 5231 size_t getNCards() { | |
| 5232 return (_g1h->capacity() + G1BlockOffsetSharedArray::N_bytes - 1) | |
| 5233 / G1BlockOffsetSharedArray::N_bytes; | |
| 5234 } | |
| 5235 CountRCClosure _count_rc_closure; | |
| 5236 public: | |
| 5237 G1ParCountRCTask(G1CollectedHeap* g1h) : | |
| 5238 AbstractGangTask("G1 Par RC Count task"), | |
| 5239 _g1h(g1h), _bm(getNCards()), _count_rc_closure(g1h) | |
| 5240 {} | |
| 5241 | |
| 5242 void work(int i) { | |
| 5243 ResourceMark rm; | |
| 5244 HandleMark hm; | |
| 5245 _g1h->g1_rem_set()->oops_into_collection_set_do(&_count_rc_closure, i); | |
| 5246 } | |
| 5247 }; | |
| 5248 | |
| 5249 void G1CollectedHeap::popularity_pause_preamble(HeapRegion* popular_region) { | |
| 5250 // We're evacuating a single region (for popularity). | |
| 5251 if (G1TracePopularity) { | |
| 5252 gclog_or_tty->print_cr("Doing pop region pause for ["PTR_FORMAT", "PTR_FORMAT")", | |
| 5253 popular_region->bottom(), popular_region->end()); | |
| 5254 } | |
| 5255 g1_policy()->set_single_region_collection_set(popular_region); | |
| 5256 size_t max_rc; | |
| 5257 if (!compute_reference_counts_and_evac_popular(popular_region, | |
| 5258 &max_rc)) { | |
| 5259 // We didn't evacuate any popular objects. | |
| 5260 // We increase the RS popularity limit, to prevent this from | |
| 5261 // happening in the future. | |
| 5262 if (G1RSPopLimit < (1 << 30)) { | |
| 5263 G1RSPopLimit *= 2; | |
| 5264 } | |
| 5265 // For now, interesting enough for a message: | |
| 5266 #if 1 | |
| 5267 gclog_or_tty->print_cr("In pop region pause for ["PTR_FORMAT", "PTR_FORMAT"), " | |
| 5268 "failed to find a pop object (max = %d).", | |
| 5269 popular_region->bottom(), popular_region->end(), | |
| 5270 max_rc); | |
| 5271 gclog_or_tty->print_cr("Increased G1RSPopLimit to %d.", G1RSPopLimit); | |
| 5272 #endif // 0 | |
| 5273 // Also, we reset the collection set to NULL, to make the rest of | |
| 5274 // the collection do nothing. | |
| 5275 assert(popular_region->next_in_collection_set() == NULL, | |
| 5276 "should be single-region."); | |
| 5277 popular_region->set_in_collection_set(false); | |
| 5278 popular_region->set_popular_pending(false); | |
| 5279 g1_policy()->clear_collection_set(); | |
| 5280 } | |
| 5281 } | |
| 5282 | |
| 5283 bool G1CollectedHeap:: | |
| 5284 compute_reference_counts_and_evac_popular(HeapRegion* popular_region, | |
| 5285 size_t* max_rc) { | |
| 5286 HeapWord* rc_region_bot; | |
| 5287 HeapWord* rc_region_end; | |
| 5288 | |
| 5289 // Set up the reference count region. | |
| 5290 HeapRegion* rc_region = newAllocRegion(HeapRegion::GrainWords); | |
| 5291 if (rc_region != NULL) { | |
| 5292 rc_region_bot = rc_region->bottom(); | |
| 5293 rc_region_end = rc_region->end(); | |
| 5294 } else { | |
| 5295 rc_region_bot = NEW_C_HEAP_ARRAY(HeapWord, HeapRegion::GrainWords); | |
| 5296 if (rc_region_bot == NULL) { | |
| 5297 vm_exit_out_of_memory(HeapRegion::GrainWords, | |
| 5298 "No space for RC region."); | |
| 5299 } | |
| 5300 rc_region_end = rc_region_bot + HeapRegion::GrainWords; | |
| 5301 } | |
| 5302 | |
| 5303 if (G1TracePopularity) | |
| 5304 gclog_or_tty->print_cr("RC region is ["PTR_FORMAT", "PTR_FORMAT")", | |
| 5305 rc_region_bot, rc_region_end); | |
| 5306 if (rc_region_bot > popular_region->bottom()) { | |
| 5307 _rc_region_above = true; | |
| 5308 _rc_region_diff = | |
| 5309 pointer_delta(rc_region_bot, popular_region->bottom(), 1); | |
| 5310 } else { | |
| 5311 assert(rc_region_bot < popular_region->bottom(), "Can't be equal."); | |
| 5312 _rc_region_above = false; | |
| 5313 _rc_region_diff = | |
| 5314 pointer_delta(popular_region->bottom(), rc_region_bot, 1); | |
| 5315 } | |
| 5316 g1_policy()->record_pop_compute_rc_start(); | |
| 5317 // Count external references. | |
| 5318 g1_rem_set()->prepare_for_oops_into_collection_set_do(); | |
| 5319 if (ParallelGCThreads > 0) { | |
| 5320 | |
| 5321 set_par_threads(workers()->total_workers()); | |
| 5322 G1ParCountRCTask par_count_rc_task(this); | |
| 5323 workers()->run_task(&par_count_rc_task); | |
| 5324 set_par_threads(0); | |
| 5325 | |
| 5326 } else { | |
| 5327 CountRCClosure count_rc_closure(this); | |
| 5328 g1_rem_set()->oops_into_collection_set_do(&count_rc_closure, 0); | |
| 5329 } | |
| 5330 g1_rem_set()->cleanup_after_oops_into_collection_set_do(); | |
| 5331 g1_policy()->record_pop_compute_rc_end(); | |
| 5332 | |
| 5333 // Now evacuate popular objects. | |
| 5334 g1_policy()->record_pop_evac_start(); | |
| 5335 EvacPopObjClosure evac_pop_obj_cl(this); | |
| 5336 popular_region->object_iterate(&evac_pop_obj_cl); | |
| 5337 *max_rc = evac_pop_obj_cl.max_rc(); | |
| 5338 | |
| 5339 // Make sure the last "top" value of the current popular region is copied | |
| 5340 // as the "next_top_at_mark_start", so that objects made popular during | |
| 5341 // markings aren't automatically considered live. | |
| 5342 HeapRegion* cur_pop_region = _hrs->at(_cur_pop_hr_index); | |
| 5343 cur_pop_region->note_end_of_copying(); | |
| 5344 | |
| 5345 if (rc_region != NULL) { | |
| 5346 free_region(rc_region); | |
| 5347 } else { | |
| 5348 FREE_C_HEAP_ARRAY(HeapWord, rc_region_bot); | |
| 5349 } | |
| 5350 g1_policy()->record_pop_evac_end(); | |
| 5351 | |
| 5352 return evac_pop_obj_cl.pop_objs() > 0; | |
| 5353 } | |
| 5354 | |
| 5355 class CountPopObjInfoClosure: public HeapRegionClosure { | |
| 5356 size_t _objs; | |
| 5357 size_t _bytes; | |
| 5358 | |
| 5359 class CountObjClosure: public ObjectClosure { | |
| 5360 int _n; | |
| 5361 public: | |
| 5362 CountObjClosure() : _n(0) {} | |
| 5363 void do_object(oop obj) { _n++; } | |
| 5364 size_t n() { return _n; } | |
| 5365 }; | |
| 5366 | |
| 5367 public: | |
| 5368 CountPopObjInfoClosure() : _objs(0), _bytes(0) {} | |
| 5369 bool doHeapRegion(HeapRegion* r) { | |
| 5370 _bytes += r->used(); | |
| 5371 CountObjClosure blk; | |
| 5372 r->object_iterate(&blk); | |
| 5373 _objs += blk.n(); | |
| 5374 return false; | |
| 5375 } | |
| 5376 size_t objs() { return _objs; } | |
| 5377 size_t bytes() { return _bytes; } | |
| 5378 }; | |
| 5379 | |
| 5380 | |
| 5381 void G1CollectedHeap::print_popularity_summary_info() const { | |
| 5382 CountPopObjInfoClosure blk; | |
| 5383 for (int i = 0; i <= _cur_pop_hr_index; i++) { | |
| 5384 blk.doHeapRegion(_hrs->at(i)); | |
| 5385 } | |
| 5386 gclog_or_tty->print_cr("\nPopular objects: %d objs, %d bytes.", | |
| 5387 blk.objs(), blk.bytes()); | |
| 5388 gclog_or_tty->print_cr(" RC at copy = [avg = %5.2f, max = %5.2f, sd = %5.2f].", | |
| 5389 _pop_obj_rc_at_copy.avg(), | |
| 5390 _pop_obj_rc_at_copy.maximum(), | |
| 5391 _pop_obj_rc_at_copy.sd()); | |
| 5392 } | |
| 5393 | |
| 5394 void G1CollectedHeap::set_refine_cte_cl_concurrency(bool concurrent) { | |
| 5395 _refine_cte_cl->set_concurrent(concurrent); | |
| 5396 } | |
| 5397 | |
| 5398 #ifndef PRODUCT | |
| 5399 | |
| 5400 class PrintHeapRegionClosure: public HeapRegionClosure { | |
| 5401 public: | |
| 5402 bool doHeapRegion(HeapRegion *r) { | |
| 5403 gclog_or_tty->print("Region: "PTR_FORMAT":", r); | |
| 5404 if (r != NULL) { | |
| 5405 if (r->is_on_free_list()) | |
| 5406 gclog_or_tty->print("Free "); | |
| 5407 if (r->is_young()) | |
| 5408 gclog_or_tty->print("Young "); | |
| 5409 if (r->isHumongous()) | |
| 5410 gclog_or_tty->print("Is Humongous "); | |
| 5411 r->print(); | |
| 5412 } | |
| 5413 return false; | |
| 5414 } | |
| 5415 }; | |
| 5416 | |
| 5417 class SortHeapRegionClosure : public HeapRegionClosure { | |
| 5418 size_t young_regions,free_regions, unclean_regions; | |
| 5419 size_t hum_regions, count; | |
| 5420 size_t unaccounted, cur_unclean, cur_alloc; | |
| 5421 size_t total_free; | |
| 5422 HeapRegion* cur; | |
| 5423 public: | |
| 5424 SortHeapRegionClosure(HeapRegion *_cur) : cur(_cur), young_regions(0), | |
| 5425 free_regions(0), unclean_regions(0), | |
| 5426 hum_regions(0), | |
| 5427 count(0), unaccounted(0), | |
| 5428 cur_alloc(0), total_free(0) | |
| 5429 {} | |
| 5430 bool doHeapRegion(HeapRegion *r) { | |
| 5431 count++; | |
| 5432 if (r->is_on_free_list()) free_regions++; | |
| 5433 else if (r->is_on_unclean_list()) unclean_regions++; | |
| 5434 else if (r->isHumongous()) hum_regions++; | |
| 5435 else if (r->is_young()) young_regions++; | |
| 5436 else if (r == cur) cur_alloc++; | |
| 5437 else unaccounted++; | |
| 5438 return false; | |
| 5439 } | |
| 5440 void print() { | |
| 5441 total_free = free_regions + unclean_regions; | |
| 5442 gclog_or_tty->print("%d regions\n", count); | |
| 5443 gclog_or_tty->print("%d free: free_list = %d unclean = %d\n", | |
| 5444 total_free, free_regions, unclean_regions); | |
| 5445 gclog_or_tty->print("%d humongous %d young\n", | |
| 5446 hum_regions, young_regions); | |
| 5447 gclog_or_tty->print("%d cur_alloc\n", cur_alloc); | |
| 5448 gclog_or_tty->print("UHOH unaccounted = %d\n", unaccounted); | |
| 5449 } | |
| 5450 }; | |
| 5451 | |
| 5452 void G1CollectedHeap::print_region_counts() { | |
| 5453 SortHeapRegionClosure sc(_cur_alloc_region); | |
| 5454 PrintHeapRegionClosure cl; | |
| 5455 heap_region_iterate(&cl); | |
| 5456 heap_region_iterate(&sc); | |
| 5457 sc.print(); | |
| 5458 print_region_accounting_info(); | |
| 5459 }; | |
| 5460 | |
| 5461 bool G1CollectedHeap::regions_accounted_for() { | |
| 5462 // TODO: regions accounting for young/survivor/tenured | |
| 5463 return true; | |
| 5464 } | |
| 5465 | |
| 5466 bool G1CollectedHeap::print_region_accounting_info() { | |
| 5467 gclog_or_tty->print_cr("P regions: %d.", G1NumPopularRegions); | |
| 5468 gclog_or_tty->print_cr("Free regions: %d (count: %d count list %d) (clean: %d unclean: %d).", | |
| 5469 free_regions(), | |
| 5470 count_free_regions(), count_free_regions_list(), | |
| 5471 _free_region_list_size, _unclean_region_list.sz()); | |
| 5472 gclog_or_tty->print_cr("cur_alloc: %d.", | |
| 5473 (_cur_alloc_region == NULL ? 0 : 1)); | |
| 5474 gclog_or_tty->print_cr("H regions: %d.", _num_humongous_regions); | |
| 5475 | |
| 5476 // TODO: check regions accounting for young/survivor/tenured | |
| 5477 return true; | |
| 5478 } | |
| 5479 | |
| 5480 bool G1CollectedHeap::is_in_closed_subset(const void* p) const { | |
| 5481 HeapRegion* hr = heap_region_containing(p); | |
| 5482 if (hr == NULL) { | |
| 5483 return is_in_permanent(p); | |
| 5484 } else { | |
| 5485 return hr->is_in(p); | |
| 5486 } | |
| 5487 } | |
| 5488 #endif // PRODUCT | |
| 5489 | |
| 5490 void G1CollectedHeap::g1_unimplemented() { | |
| 5491 // Unimplemented(); | |
| 5492 } | |
| 5493 | |
| 5494 | |
| 5495 // Local Variables: *** | |
| 5496 // c-indentation-style: gnu *** | |
| 5497 // End: *** |