1 /* 2 * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "gc_implementation/g1/concurrentG1Refine.hpp" 27 #include "gc_implementation/g1/g1BlockOffsetTable.inline.hpp" 28 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" 29 #include "gc_implementation/g1/heapRegionRemSet.hpp" 30 #include "gc_implementation/g1/heapRegionManager.inline.hpp" 31 #include "memory/allocation.hpp" 32 #include "memory/padded.inline.hpp" 33 #include "memory/space.inline.hpp" 34 #include "oops/oop.inline.hpp" 35 #include "utilities/bitMap.inline.hpp" 36 #include "utilities/globalDefinitions.hpp" 37 #include "utilities/growableArray.hpp" 38 39 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 40 41 class PerRegionTable: public CHeapObj<mtGC> { 42 friend class OtherRegionsTable; 43 friend class HeapRegionRemSetIterator; 44 45 HeapRegion* _hr; 46 BitMap _bm; 47 jint _occupied; 48 49 // next pointer for free/allocated 'all' list 50 PerRegionTable* _next; 51 52 // prev pointer for the allocated 'all' list 53 PerRegionTable* _prev; 54 55 // next pointer in collision list 56 PerRegionTable * _collision_list_next; 57 58 // Global free list of PRTs 59 static PerRegionTable* _free_list; 60 61 protected: 62 // We need access in order to union things into the base table. 63 BitMap* bm() { return &_bm; } 64 65 void recount_occupied() { 66 _occupied = (jint) bm()->count_one_bits(); 67 } 68 69 PerRegionTable(HeapRegion* hr) : 70 _hr(hr), 71 _occupied(0), 72 _bm(HeapRegion::CardsPerRegion, false /* in-resource-area */), 73 _collision_list_next(NULL), _next(NULL), _prev(NULL) 74 {} 75 76 void add_card_work(CardIdx_t from_card, bool par) { 77 if (!_bm.at(from_card)) { 78 if (par) { 79 if (_bm.par_at_put(from_card, 1)) { 80 Atomic::inc(&_occupied); 81 } 82 } else { 83 _bm.at_put(from_card, 1); 84 _occupied++; 85 } 86 } 87 } 88 89 void add_reference_work(OopOrNarrowOopStar from, bool par) { 90 // Must make this robust in case "from" is not in "_hr", because of 91 // concurrency. 92 93 if (G1TraceHeapRegionRememberedSet) { 94 gclog_or_tty->print_cr(" PRT::Add_reference_work(" PTR_FORMAT "->" PTR_FORMAT").", 95 from, 96 UseCompressedOops 97 ? (void *)oopDesc::load_decode_heap_oop((narrowOop*)from) 98 : (void *)oopDesc::load_decode_heap_oop((oop*)from)); 99 } 100 101 HeapRegion* loc_hr = hr(); 102 // If the test below fails, then this table was reused concurrently 103 // with this operation. This is OK, since the old table was coarsened, 104 // and adding a bit to the new table is never incorrect. 105 // If the table used to belong to a continues humongous region and is 106 // now reused for the corresponding start humongous region, we need to 107 // make sure that we detect this. Thus, we call is_in_reserved_raw() 108 // instead of just is_in_reserved() here. 109 if (loc_hr->is_in_reserved_raw(from)) { 110 size_t hw_offset = pointer_delta((HeapWord*)from, loc_hr->bottom()); 111 CardIdx_t from_card = (CardIdx_t) 112 hw_offset >> (CardTableModRefBS::card_shift - LogHeapWordSize); 113 114 assert(0 <= from_card && (size_t)from_card < HeapRegion::CardsPerRegion, 115 "Must be in range."); 116 add_card_work(from_card, par); 117 } 118 } 119 120 public: 121 122 HeapRegion* hr() const { return _hr; } 123 124 jint occupied() const { 125 // Overkill, but if we ever need it... 126 // guarantee(_occupied == _bm.count_one_bits(), "Check"); 127 return _occupied; 128 } 129 130 void init(HeapRegion* hr, bool clear_links_to_all_list) { 131 if (clear_links_to_all_list) { 132 set_next(NULL); 133 set_prev(NULL); 134 } 135 _hr = hr; 136 _collision_list_next = NULL; 137 _occupied = 0; 138 _bm.clear(); 139 } 140 141 void add_reference(OopOrNarrowOopStar from) { 142 add_reference_work(from, /*parallel*/ true); 143 } 144 145 void seq_add_reference(OopOrNarrowOopStar from) { 146 add_reference_work(from, /*parallel*/ false); 147 } 148 149 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) { 150 HeapWord* hr_bot = hr()->bottom(); 151 size_t hr_first_card_index = ctbs->index_for(hr_bot); 152 bm()->set_intersection_at_offset(*card_bm, hr_first_card_index); 153 recount_occupied(); 154 } 155 156 void add_card(CardIdx_t from_card_index) { 157 add_card_work(from_card_index, /*parallel*/ true); 158 } 159 160 void seq_add_card(CardIdx_t from_card_index) { 161 add_card_work(from_card_index, /*parallel*/ false); 162 } 163 164 // (Destructively) union the bitmap of the current table into the given 165 // bitmap (which is assumed to be of the same size.) 166 void union_bitmap_into(BitMap* bm) { 167 bm->set_union(_bm); 168 } 169 170 // Mem size in bytes. 171 size_t mem_size() const { 172 return sizeof(PerRegionTable) + _bm.size_in_words() * HeapWordSize; 173 } 174 175 // Requires "from" to be in "hr()". 176 bool contains_reference(OopOrNarrowOopStar from) const { 177 assert(hr()->is_in_reserved(from), "Precondition."); 178 size_t card_ind = pointer_delta(from, hr()->bottom(), 179 CardTableModRefBS::card_size); 180 return _bm.at(card_ind); 181 } 182 183 // Bulk-free the PRTs from prt to last, assumes that they are 184 // linked together using their _next field. 185 static void bulk_free(PerRegionTable* prt, PerRegionTable* last) { 186 while (true) { 187 PerRegionTable* fl = _free_list; 188 last->set_next(fl); 189 PerRegionTable* res = (PerRegionTable*) Atomic::cmpxchg_ptr(prt, &_free_list, fl); 190 if (res == fl) { 191 return; 192 } 193 } 194 ShouldNotReachHere(); 195 } 196 197 static void free(PerRegionTable* prt) { 198 bulk_free(prt, prt); 199 } 200 201 // Returns an initialized PerRegionTable instance. 202 static PerRegionTable* alloc(HeapRegion* hr) { 203 PerRegionTable* fl = _free_list; 204 while (fl != NULL) { 205 PerRegionTable* nxt = fl->next(); 206 PerRegionTable* res = 207 (PerRegionTable*) 208 Atomic::cmpxchg_ptr(nxt, &_free_list, fl); 209 if (res == fl) { 210 fl->init(hr, true); 211 return fl; 212 } else { 213 fl = _free_list; 214 } 215 } 216 assert(fl == NULL, "Loop condition."); 217 return new PerRegionTable(hr); 218 } 219 220 PerRegionTable* next() const { return _next; } 221 void set_next(PerRegionTable* next) { _next = next; } 222 PerRegionTable* prev() const { return _prev; } 223 void set_prev(PerRegionTable* prev) { _prev = prev; } 224 225 // Accessor and Modification routines for the pointer for the 226 // singly linked collision list that links the PRTs within the 227 // OtherRegionsTable::_fine_grain_regions hash table. 228 // 229 // It might be useful to also make the collision list doubly linked 230 // to avoid iteration over the collisions list during scrubbing/deletion. 231 // OTOH there might not be many collisions. 232 233 PerRegionTable* collision_list_next() const { 234 return _collision_list_next; 235 } 236 237 void set_collision_list_next(PerRegionTable* next) { 238 _collision_list_next = next; 239 } 240 241 PerRegionTable** collision_list_next_addr() { 242 return &_collision_list_next; 243 } 244 245 static size_t fl_mem_size() { 246 PerRegionTable* cur = _free_list; 247 size_t res = 0; 248 while (cur != NULL) { 249 res += cur->mem_size(); 250 cur = cur->next(); 251 } 252 return res; 253 } 254 255 static void test_fl_mem_size(); 256 }; 257 258 PerRegionTable* PerRegionTable::_free_list = NULL; 259 260 size_t OtherRegionsTable::_max_fine_entries = 0; 261 size_t OtherRegionsTable::_mod_max_fine_entries_mask = 0; 262 size_t OtherRegionsTable::_fine_eviction_stride = 0; 263 size_t OtherRegionsTable::_fine_eviction_sample_size = 0; 264 265 OtherRegionsTable::OtherRegionsTable(HeapRegion* hr, Mutex* m) : 266 _g1h(G1CollectedHeap::heap()), 267 _hr(hr), _m(m), 268 _coarse_map(G1CollectedHeap::heap()->max_regions(), 269 false /* in-resource-area */), 270 _fine_grain_regions(NULL), 271 _first_all_fine_prts(NULL), _last_all_fine_prts(NULL), 272 _n_fine_entries(0), _n_coarse_entries(0), 273 _fine_eviction_start(0), 274 _sparse_table(hr) 275 { 276 typedef PerRegionTable* PerRegionTablePtr; 277 278 if (_max_fine_entries == 0) { 279 assert(_mod_max_fine_entries_mask == 0, "Both or none."); 280 size_t max_entries_log = (size_t)log2_long((jlong)G1RSetRegionEntries); 281 _max_fine_entries = (size_t)1 << max_entries_log; 282 _mod_max_fine_entries_mask = _max_fine_entries - 1; 283 284 assert(_fine_eviction_sample_size == 0 285 && _fine_eviction_stride == 0, "All init at same time."); 286 _fine_eviction_sample_size = MAX2((size_t)4, max_entries_log); 287 _fine_eviction_stride = _max_fine_entries / _fine_eviction_sample_size; 288 } 289 290 _fine_grain_regions = NEW_C_HEAP_ARRAY3(PerRegionTablePtr, _max_fine_entries, 291 mtGC, CURRENT_PC, AllocFailStrategy::RETURN_NULL); 292 293 if (_fine_grain_regions == NULL) { 294 vm_exit_out_of_memory(sizeof(void*)*_max_fine_entries, OOM_MALLOC_ERROR, 295 "Failed to allocate _fine_grain_entries."); 296 } 297 298 for (size_t i = 0; i < _max_fine_entries; i++) { 299 _fine_grain_regions[i] = NULL; 300 } 301 } 302 303 void OtherRegionsTable::link_to_all(PerRegionTable* prt) { 304 // We always append to the beginning of the list for convenience; 305 // the order of entries in this list does not matter. 306 if (_first_all_fine_prts != NULL) { 307 assert(_first_all_fine_prts->prev() == NULL, "invariant"); 308 _first_all_fine_prts->set_prev(prt); 309 prt->set_next(_first_all_fine_prts); 310 } else { 311 // this is the first element we insert. Adjust the "last" pointer 312 _last_all_fine_prts = prt; 313 assert(prt->next() == NULL, "just checking"); 314 } 315 // the new element is always the first element without a predecessor 316 prt->set_prev(NULL); 317 _first_all_fine_prts = prt; 318 319 assert(prt->prev() == NULL, "just checking"); 320 assert(_first_all_fine_prts == prt, "just checking"); 321 assert((_first_all_fine_prts == NULL && _last_all_fine_prts == NULL) || 322 (_first_all_fine_prts != NULL && _last_all_fine_prts != NULL), 323 "just checking"); 324 assert(_last_all_fine_prts == NULL || _last_all_fine_prts->next() == NULL, 325 "just checking"); 326 assert(_first_all_fine_prts == NULL || _first_all_fine_prts->prev() == NULL, 327 "just checking"); 328 } 329 330 void OtherRegionsTable::unlink_from_all(PerRegionTable* prt) { 331 if (prt->prev() != NULL) { 332 assert(_first_all_fine_prts != prt, "just checking"); 333 prt->prev()->set_next(prt->next()); 334 // removing the last element in the list? 335 if (_last_all_fine_prts == prt) { 336 _last_all_fine_prts = prt->prev(); 337 } 338 } else { 339 assert(_first_all_fine_prts == prt, "just checking"); 340 _first_all_fine_prts = prt->next(); 341 // list is empty now? 342 if (_first_all_fine_prts == NULL) { 343 _last_all_fine_prts = NULL; 344 } 345 } 346 347 if (prt->next() != NULL) { 348 prt->next()->set_prev(prt->prev()); 349 } 350 351 prt->set_next(NULL); 352 prt->set_prev(NULL); 353 354 assert((_first_all_fine_prts == NULL && _last_all_fine_prts == NULL) || 355 (_first_all_fine_prts != NULL && _last_all_fine_prts != NULL), 356 "just checking"); 357 assert(_last_all_fine_prts == NULL || _last_all_fine_prts->next() == NULL, 358 "just checking"); 359 assert(_first_all_fine_prts == NULL || _first_all_fine_prts->prev() == NULL, 360 "just checking"); 361 } 362 363 int** FromCardCache::_cache = NULL; 364 uint FromCardCache::_max_regions = 0; 365 size_t FromCardCache::_static_mem_size = 0; 366 367 void FromCardCache::initialize(uint n_par_rs, uint max_num_regions) { 368 guarantee(_cache == NULL, "Should not call this multiple times"); 369 370 _max_regions = max_num_regions; 371 _cache = Padded2DArray<int, mtGC>::create_unfreeable(n_par_rs, 372 _max_regions, 373 &_static_mem_size); 374 375 invalidate(0, _max_regions); 376 } 377 378 void FromCardCache::invalidate(uint start_idx, size_t new_num_regions) { 379 guarantee((size_t)start_idx + new_num_regions <= max_uintx, 380 err_msg("Trying to invalidate beyond maximum region, from %u size "SIZE_FORMAT, 381 start_idx, new_num_regions)); 382 for (uint i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) { 383 uint end_idx = (start_idx + (uint)new_num_regions); 384 assert(end_idx <= _max_regions, "Must be within max."); 385 for (uint j = start_idx; j < end_idx; j++) { 386 set(i, j, InvalidCard); 387 } 388 } 389 } 390 391 #ifndef PRODUCT 392 void FromCardCache::print(outputStream* out) { 393 for (uint i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) { 394 for (uint j = 0; j < _max_regions; j++) { 395 out->print_cr("_from_card_cache["UINT32_FORMAT"]["UINT32_FORMAT"] = "INT32_FORMAT".", 396 i, j, at(i, j)); 397 } 398 } 399 } 400 #endif 401 402 void FromCardCache::clear(uint region_idx) { 403 uint num_par_remsets = HeapRegionRemSet::num_par_rem_sets(); 404 for (uint i = 0; i < num_par_remsets; i++) { 405 set(i, region_idx, InvalidCard); 406 } 407 } 408 409 void OtherRegionsTable::initialize(uint max_regions) { 410 FromCardCache::initialize(HeapRegionRemSet::num_par_rem_sets(), max_regions); 411 } 412 413 void OtherRegionsTable::invalidate(uint start_idx, size_t num_regions) { 414 FromCardCache::invalidate(start_idx, num_regions); 415 } 416 417 void OtherRegionsTable::print_from_card_cache() { 418 FromCardCache::print(); 419 } 420 421 void OtherRegionsTable::add_reference(OopOrNarrowOopStar from, int tid) { 422 uint cur_hrm_ind = hr()->hrm_index(); 423 424 if (G1TraceHeapRegionRememberedSet) { 425 gclog_or_tty->print_cr("ORT::add_reference_work(" PTR_FORMAT "->" PTR_FORMAT ").", 426 from, 427 UseCompressedOops 428 ? (void *)oopDesc::load_decode_heap_oop((narrowOop*)from) 429 : (void *)oopDesc::load_decode_heap_oop((oop*)from)); 430 } 431 432 int from_card = (int)(uintptr_t(from) >> CardTableModRefBS::card_shift); 433 434 if (G1TraceHeapRegionRememberedSet) { 435 gclog_or_tty->print_cr("Table for [" PTR_FORMAT "...): card %d (cache = "INT32_FORMAT")", 436 hr()->bottom(), from_card, 437 FromCardCache::at((uint)tid, cur_hrm_ind)); 438 } 439 440 if (FromCardCache::contains_or_replace((uint)tid, cur_hrm_ind, from_card)) { 441 if (G1TraceHeapRegionRememberedSet) { 442 gclog_or_tty->print_cr(" from-card cache hit."); 443 } 444 assert(contains_reference(from), "We just added it!"); 445 return; 446 } 447 448 // Note that this may be a continued H region. 449 HeapRegion* from_hr = _g1h->heap_region_containing_raw(from); 450 RegionIdx_t from_hrm_ind = (RegionIdx_t) from_hr->hrm_index(); 451 452 // If the region is already coarsened, return. 453 if (_coarse_map.at(from_hrm_ind)) { 454 if (G1TraceHeapRegionRememberedSet) { 455 gclog_or_tty->print_cr(" coarse map hit."); 456 } 457 assert(contains_reference(from), "We just added it!"); 458 return; 459 } 460 461 // Otherwise find a per-region table to add it to. 462 size_t ind = from_hrm_ind & _mod_max_fine_entries_mask; 463 PerRegionTable* prt = find_region_table(ind, from_hr); 464 if (prt == NULL) { 465 MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag); 466 // Confirm that it's really not there... 467 prt = find_region_table(ind, from_hr); 468 if (prt == NULL) { 469 470 uintptr_t from_hr_bot_card_index = 471 uintptr_t(from_hr->bottom()) 472 >> CardTableModRefBS::card_shift; 473 CardIdx_t card_index = from_card - from_hr_bot_card_index; 474 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion, 475 "Must be in range."); 476 if (G1HRRSUseSparseTable && 477 _sparse_table.add_card(from_hrm_ind, card_index)) { 478 if (G1RecordHRRSOops) { 479 HeapRegionRemSet::record(hr(), from); 480 if (G1TraceHeapRegionRememberedSet) { 481 gclog_or_tty->print(" Added card " PTR_FORMAT " to region " 482 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n", 483 align_size_down(uintptr_t(from), 484 CardTableModRefBS::card_size), 485 hr()->bottom(), from); 486 } 487 } 488 if (G1TraceHeapRegionRememberedSet) { 489 gclog_or_tty->print_cr(" added card to sparse table."); 490 } 491 assert(contains_reference_locked(from), "We just added it!"); 492 return; 493 } else { 494 if (G1TraceHeapRegionRememberedSet) { 495 gclog_or_tty->print_cr(" [tid %d] sparse table entry " 496 "overflow(f: %d, t: %u)", 497 tid, from_hrm_ind, cur_hrm_ind); 498 } 499 } 500 501 if (_n_fine_entries == _max_fine_entries) { 502 prt = delete_region_table(); 503 // There is no need to clear the links to the 'all' list here: 504 // prt will be reused immediately, i.e. remain in the 'all' list. 505 prt->init(from_hr, false /* clear_links_to_all_list */); 506 } else { 507 prt = PerRegionTable::alloc(from_hr); 508 link_to_all(prt); 509 } 510 511 PerRegionTable* first_prt = _fine_grain_regions[ind]; 512 prt->set_collision_list_next(first_prt); 513 _fine_grain_regions[ind] = prt; 514 _n_fine_entries++; 515 516 if (G1HRRSUseSparseTable) { 517 // Transfer from sparse to fine-grain. 518 SparsePRTEntry *sprt_entry = _sparse_table.get_entry(from_hrm_ind); 519 assert(sprt_entry != NULL, "There should have been an entry"); 520 for (int i = 0; i < SparsePRTEntry::cards_num(); i++) { 521 CardIdx_t c = sprt_entry->card(i); 522 if (c != SparsePRTEntry::NullEntry) { 523 prt->add_card(c); 524 } 525 } 526 // Now we can delete the sparse entry. 527 bool res = _sparse_table.delete_entry(from_hrm_ind); 528 assert(res, "It should have been there."); 529 } 530 } 531 assert(prt != NULL && prt->hr() == from_hr, "consequence"); 532 } 533 // Note that we can't assert "prt->hr() == from_hr", because of the 534 // possibility of concurrent reuse. But see head comment of 535 // OtherRegionsTable for why this is OK. 536 assert(prt != NULL, "Inv"); 537 538 prt->add_reference(from); 539 540 if (G1RecordHRRSOops) { 541 HeapRegionRemSet::record(hr(), from); 542 if (G1TraceHeapRegionRememberedSet) { 543 gclog_or_tty->print("Added card " PTR_FORMAT " to region " 544 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n", 545 align_size_down(uintptr_t(from), 546 CardTableModRefBS::card_size), 547 hr()->bottom(), from); 548 } 549 } 550 assert(contains_reference(from), "We just added it!"); 551 } 552 553 PerRegionTable* 554 OtherRegionsTable::find_region_table(size_t ind, HeapRegion* hr) const { 555 assert(0 <= ind && ind < _max_fine_entries, "Preconditions."); 556 PerRegionTable* prt = _fine_grain_regions[ind]; 557 while (prt != NULL && prt->hr() != hr) { 558 prt = prt->collision_list_next(); 559 } 560 // Loop postcondition is the method postcondition. 561 return prt; 562 } 563 564 jint OtherRegionsTable::_n_coarsenings = 0; 565 566 PerRegionTable* OtherRegionsTable::delete_region_table() { 567 assert(_m->owned_by_self(), "Precondition"); 568 assert(_n_fine_entries == _max_fine_entries, "Precondition"); 569 PerRegionTable* max = NULL; 570 jint max_occ = 0; 571 PerRegionTable** max_prev; 572 size_t max_ind; 573 574 size_t i = _fine_eviction_start; 575 for (size_t k = 0; k < _fine_eviction_sample_size; k++) { 576 size_t ii = i; 577 // Make sure we get a non-NULL sample. 578 while (_fine_grain_regions[ii] == NULL) { 579 ii++; 580 if (ii == _max_fine_entries) ii = 0; 581 guarantee(ii != i, "We must find one."); 582 } 583 PerRegionTable** prev = &_fine_grain_regions[ii]; 584 PerRegionTable* cur = *prev; 585 while (cur != NULL) { 586 jint cur_occ = cur->occupied(); 587 if (max == NULL || cur_occ > max_occ) { 588 max = cur; 589 max_prev = prev; 590 max_ind = i; 591 max_occ = cur_occ; 592 } 593 prev = cur->collision_list_next_addr(); 594 cur = cur->collision_list_next(); 595 } 596 i = i + _fine_eviction_stride; 597 if (i >= _n_fine_entries) i = i - _n_fine_entries; 598 } 599 600 _fine_eviction_start++; 601 602 if (_fine_eviction_start >= _n_fine_entries) { 603 _fine_eviction_start -= _n_fine_entries; 604 } 605 606 guarantee(max != NULL, "Since _n_fine_entries > 0"); 607 608 // Set the corresponding coarse bit. 609 size_t max_hrm_index = (size_t) max->hr()->hrm_index(); 610 if (!_coarse_map.at(max_hrm_index)) { 611 _coarse_map.at_put(max_hrm_index, true); 612 _n_coarse_entries++; 613 if (G1TraceHeapRegionRememberedSet) { 614 gclog_or_tty->print("Coarsened entry in region [" PTR_FORMAT "...] " 615 "for region [" PTR_FORMAT "...] (%d coarse entries).\n", 616 hr()->bottom(), 617 max->hr()->bottom(), 618 _n_coarse_entries); 619 } 620 } 621 622 // Unsplice. 623 *max_prev = max->collision_list_next(); 624 Atomic::inc(&_n_coarsenings); 625 _n_fine_entries--; 626 return max; 627 } 628 629 630 // At present, this must be called stop-world single-threaded. 631 void OtherRegionsTable::scrub(CardTableModRefBS* ctbs, 632 BitMap* region_bm, BitMap* card_bm) { 633 // First eliminated garbage regions from the coarse map. 634 if (G1RSScrubVerbose) { 635 gclog_or_tty->print_cr("Scrubbing region %u:", hr()->hrm_index()); 636 } 637 638 assert(_coarse_map.size() == region_bm->size(), "Precondition"); 639 if (G1RSScrubVerbose) { 640 gclog_or_tty->print(" Coarse map: before = "SIZE_FORMAT"...", 641 _n_coarse_entries); 642 } 643 _coarse_map.set_intersection(*region_bm); 644 _n_coarse_entries = _coarse_map.count_one_bits(); 645 if (G1RSScrubVerbose) { 646 gclog_or_tty->print_cr(" after = "SIZE_FORMAT".", _n_coarse_entries); 647 } 648 649 // Now do the fine-grained maps. 650 for (size_t i = 0; i < _max_fine_entries; i++) { 651 PerRegionTable* cur = _fine_grain_regions[i]; 652 PerRegionTable** prev = &_fine_grain_regions[i]; 653 while (cur != NULL) { 654 PerRegionTable* nxt = cur->collision_list_next(); 655 // If the entire region is dead, eliminate. 656 if (G1RSScrubVerbose) { 657 gclog_or_tty->print_cr(" For other region %u:", 658 cur->hr()->hrm_index()); 659 } 660 if (!region_bm->at((size_t) cur->hr()->hrm_index())) { 661 *prev = nxt; 662 cur->set_collision_list_next(NULL); 663 _n_fine_entries--; 664 if (G1RSScrubVerbose) { 665 gclog_or_tty->print_cr(" deleted via region map."); 666 } 667 unlink_from_all(cur); 668 PerRegionTable::free(cur); 669 } else { 670 // Do fine-grain elimination. 671 if (G1RSScrubVerbose) { 672 gclog_or_tty->print(" occ: before = %4d.", cur->occupied()); 673 } 674 cur->scrub(ctbs, card_bm); 675 if (G1RSScrubVerbose) { 676 gclog_or_tty->print_cr(" after = %4d.", cur->occupied()); 677 } 678 // Did that empty the table completely? 679 if (cur->occupied() == 0) { 680 *prev = nxt; 681 cur->set_collision_list_next(NULL); 682 _n_fine_entries--; 683 unlink_from_all(cur); 684 PerRegionTable::free(cur); 685 } else { 686 prev = cur->collision_list_next_addr(); 687 } 688 } 689 cur = nxt; 690 } 691 } 692 // Since we may have deleted a from_card_cache entry from the RS, clear 693 // the FCC. 694 clear_fcc(); 695 } 696 697 bool OtherRegionsTable::is_empty() const { 698 return occ_sparse() == 0 && occ_coarse() == 0 && _first_all_fine_prts == NULL; 699 } 700 701 size_t OtherRegionsTable::occupied() const { 702 size_t sum = occ_fine(); 703 sum += occ_sparse(); 704 sum += occ_coarse(); 705 return sum; 706 } 707 708 size_t OtherRegionsTable::occ_fine() const { 709 size_t sum = 0; 710 711 size_t num = 0; 712 PerRegionTable * cur = _first_all_fine_prts; 713 while (cur != NULL) { 714 sum += cur->occupied(); 715 cur = cur->next(); 716 num++; 717 } 718 guarantee(num == _n_fine_entries, "just checking"); 719 return sum; 720 } 721 722 size_t OtherRegionsTable::occ_coarse() const { 723 return (_n_coarse_entries * HeapRegion::CardsPerRegion); 724 } 725 726 size_t OtherRegionsTable::occ_sparse() const { 727 return _sparse_table.occupied(); 728 } 729 730 size_t OtherRegionsTable::mem_size() const { 731 size_t sum = 0; 732 // all PRTs are of the same size so it is sufficient to query only one of them. 733 if (_first_all_fine_prts != NULL) { 734 assert(_last_all_fine_prts != NULL && 735 _first_all_fine_prts->mem_size() == _last_all_fine_prts->mem_size(), "check that mem_size() is constant"); 736 sum += _first_all_fine_prts->mem_size() * _n_fine_entries; 737 } 738 sum += (sizeof(PerRegionTable*) * _max_fine_entries); 739 sum += (_coarse_map.size_in_words() * HeapWordSize); 740 sum += (_sparse_table.mem_size()); 741 sum += sizeof(OtherRegionsTable) - sizeof(_sparse_table); // Avoid double counting above. 742 return sum; 743 } 744 745 size_t OtherRegionsTable::static_mem_size() { 746 return FromCardCache::static_mem_size(); 747 } 748 749 size_t OtherRegionsTable::fl_mem_size() { 750 return PerRegionTable::fl_mem_size(); 751 } 752 753 void OtherRegionsTable::clear_fcc() { 754 FromCardCache::clear(hr()->hrm_index()); 755 } 756 757 void OtherRegionsTable::clear() { 758 // if there are no entries, skip this step 759 if (_first_all_fine_prts != NULL) { 760 guarantee(_first_all_fine_prts != NULL && _last_all_fine_prts != NULL, "just checking"); 761 PerRegionTable::bulk_free(_first_all_fine_prts, _last_all_fine_prts); 762 memset(_fine_grain_regions, 0, _max_fine_entries * sizeof(_fine_grain_regions[0])); 763 } else { 764 guarantee(_first_all_fine_prts == NULL && _last_all_fine_prts == NULL, "just checking"); 765 } 766 767 _first_all_fine_prts = _last_all_fine_prts = NULL; 768 _sparse_table.clear(); 769 _coarse_map.clear(); 770 _n_fine_entries = 0; 771 _n_coarse_entries = 0; 772 773 clear_fcc(); 774 } 775 776 bool OtherRegionsTable::del_single_region_table(size_t ind, 777 HeapRegion* hr) { 778 assert(0 <= ind && ind < _max_fine_entries, "Preconditions."); 779 PerRegionTable** prev_addr = &_fine_grain_regions[ind]; 780 PerRegionTable* prt = *prev_addr; 781 while (prt != NULL && prt->hr() != hr) { 782 prev_addr = prt->collision_list_next_addr(); 783 prt = prt->collision_list_next(); 784 } 785 if (prt != NULL) { 786 assert(prt->hr() == hr, "Loop postcondition."); 787 *prev_addr = prt->collision_list_next(); 788 unlink_from_all(prt); 789 PerRegionTable::free(prt); 790 _n_fine_entries--; 791 return true; 792 } else { 793 return false; 794 } 795 } 796 797 bool OtherRegionsTable::contains_reference(OopOrNarrowOopStar from) const { 798 // Cast away const in this case. 799 MutexLockerEx x((Mutex*)_m, Mutex::_no_safepoint_check_flag); 800 return contains_reference_locked(from); 801 } 802 803 bool OtherRegionsTable::contains_reference_locked(OopOrNarrowOopStar from) const { 804 HeapRegion* hr = _g1h->heap_region_containing_raw(from); 805 RegionIdx_t hr_ind = (RegionIdx_t) hr->hrm_index(); 806 // Is this region in the coarse map? 807 if (_coarse_map.at(hr_ind)) return true; 808 809 PerRegionTable* prt = find_region_table(hr_ind & _mod_max_fine_entries_mask, 810 hr); 811 if (prt != NULL) { 812 return prt->contains_reference(from); 813 814 } else { 815 uintptr_t from_card = 816 (uintptr_t(from) >> CardTableModRefBS::card_shift); 817 uintptr_t hr_bot_card_index = 818 uintptr_t(hr->bottom()) >> CardTableModRefBS::card_shift; 819 assert(from_card >= hr_bot_card_index, "Inv"); 820 CardIdx_t card_index = from_card - hr_bot_card_index; 821 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion, 822 "Must be in range."); 823 return _sparse_table.contains_card(hr_ind, card_index); 824 } 825 } 826 827 void 828 OtherRegionsTable::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) { 829 _sparse_table.do_cleanup_work(hrrs_cleanup_task); 830 } 831 832 // Determines how many threads can add records to an rset in parallel. 833 // This can be done by either mutator threads together with the 834 // concurrent refinement threads or GC threads. 835 uint HeapRegionRemSet::num_par_rem_sets() { 836 return MAX2(DirtyCardQueueSet::num_par_ids() + ConcurrentG1Refine::thread_num(), (uint)ParallelGCThreads); 837 } 838 839 HeapRegionRemSet::HeapRegionRemSet(G1BlockOffsetSharedArray* bosa, 840 HeapRegion* hr) 841 : _bosa(bosa), 842 _m(Mutex::leaf, FormatBuffer<128>("HeapRegionRemSet lock #%u", hr->hrm_index()), true), 843 _code_roots(), _other_regions(hr, &_m), _iter_state(Unclaimed), _iter_claimed(0) { 844 reset_for_par_iteration(); 845 } 846 847 void HeapRegionRemSet::setup_remset_size() { 848 // Setup sparse and fine-grain tables sizes. 849 // table_size = base * (log(region_size / 1M) + 1) 850 const int LOG_M = 20; 851 int region_size_log_mb = MAX2(HeapRegion::LogOfHRGrainBytes - LOG_M, 0); 852 if (FLAG_IS_DEFAULT(G1RSetSparseRegionEntries)) { 853 G1RSetSparseRegionEntries = G1RSetSparseRegionEntriesBase * (region_size_log_mb + 1); 854 } 855 if (FLAG_IS_DEFAULT(G1RSetRegionEntries)) { 856 G1RSetRegionEntries = G1RSetRegionEntriesBase * (region_size_log_mb + 1); 857 } 858 guarantee(G1RSetSparseRegionEntries > 0 && G1RSetRegionEntries > 0 , "Sanity"); 859 } 860 861 bool HeapRegionRemSet::claim_iter() { 862 if (_iter_state != Unclaimed) return false; 863 jint res = Atomic::cmpxchg(Claimed, (jint*)(&_iter_state), Unclaimed); 864 return (res == Unclaimed); 865 } 866 867 void HeapRegionRemSet::set_iter_complete() { 868 _iter_state = Complete; 869 } 870 871 bool HeapRegionRemSet::iter_is_complete() { 872 return _iter_state == Complete; 873 } 874 875 #ifndef PRODUCT 876 void HeapRegionRemSet::print() { 877 HeapRegionRemSetIterator iter(this); 878 size_t card_index; 879 while (iter.has_next(card_index)) { 880 HeapWord* card_start = 881 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index); 882 gclog_or_tty->print_cr(" Card " PTR_FORMAT, card_start); 883 } 884 if (iter.n_yielded() != occupied()) { 885 gclog_or_tty->print_cr("Yielded disagrees with occupied:"); 886 gclog_or_tty->print_cr(" %6d yielded (%6d coarse, %6d fine).", 887 iter.n_yielded(), 888 iter.n_yielded_coarse(), iter.n_yielded_fine()); 889 gclog_or_tty->print_cr(" %6d occ (%6d coarse, %6d fine).", 890 occupied(), occ_coarse(), occ_fine()); 891 } 892 guarantee(iter.n_yielded() == occupied(), 893 "We should have yielded all the represented cards."); 894 } 895 #endif 896 897 void HeapRegionRemSet::cleanup() { 898 SparsePRT::cleanup_all(); 899 } 900 901 void HeapRegionRemSet::clear() { 902 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag); 903 clear_locked(); 904 } 905 906 void HeapRegionRemSet::clear_locked() { 907 _code_roots.clear(); 908 _other_regions.clear(); 909 assert(occupied_locked() == 0, "Should be clear."); 910 reset_for_par_iteration(); 911 } 912 913 void HeapRegionRemSet::reset_for_par_iteration() { 914 _iter_state = Unclaimed; 915 _iter_claimed = 0; 916 // It's good to check this to make sure that the two methods are in sync. 917 assert(verify_ready_for_par_iteration(), "post-condition"); 918 } 919 920 void HeapRegionRemSet::scrub(CardTableModRefBS* ctbs, 921 BitMap* region_bm, BitMap* card_bm) { 922 _other_regions.scrub(ctbs, region_bm, card_bm); 923 } 924 925 // Code roots support 926 // 927 // The code root set is protected by two separate locking schemes 928 // When at safepoint the per-hrrs lock must be held during modifications 929 // except when doing a full gc. 930 // When not at safepoint the CodeCache_lock must be held during modifications. 931 // When concurrent readers access the contains() function 932 // (during the evacuation phase) no removals are allowed. 933 934 void HeapRegionRemSet::add_strong_code_root(nmethod* nm) { 935 assert(nm != NULL, "sanity"); 936 // Optimistic unlocked contains-check 937 if (!_code_roots.contains(nm)) { 938 MutexLockerEx ml(&_m, Mutex::_no_safepoint_check_flag); 939 add_strong_code_root_locked(nm); 940 } 941 } 942 943 void HeapRegionRemSet::add_strong_code_root_locked(nmethod* nm) { 944 assert(nm != NULL, "sanity"); 945 _code_roots.add(nm); 946 } 947 948 void HeapRegionRemSet::remove_strong_code_root(nmethod* nm) { 949 assert(nm != NULL, "sanity"); 950 assert_locked_or_safepoint(CodeCache_lock); 951 952 MutexLockerEx ml(CodeCache_lock->owned_by_self() ? NULL : &_m, Mutex::_no_safepoint_check_flag); 953 _code_roots.remove(nm); 954 955 // Check that there were no duplicates 956 guarantee(!_code_roots.contains(nm), "duplicate entry found"); 957 } 958 959 void HeapRegionRemSet::strong_code_roots_do(CodeBlobClosure* blk) const { 960 _code_roots.nmethods_do(blk); 961 } 962 963 void HeapRegionRemSet::clean_strong_code_roots(HeapRegion* hr) { 964 _code_roots.clean(hr); 965 } 966 967 size_t HeapRegionRemSet::strong_code_roots_mem_size() { 968 return _code_roots.mem_size(); 969 } 970 971 HeapRegionRemSetIterator:: HeapRegionRemSetIterator(HeapRegionRemSet* hrrs) : 972 _hrrs(hrrs), 973 _g1h(G1CollectedHeap::heap()), 974 _coarse_map(&hrrs->_other_regions._coarse_map), 975 _bosa(hrrs->bosa()), 976 _is(Sparse), 977 // Set these values so that we increment to the first region. 978 _coarse_cur_region_index(-1), 979 _coarse_cur_region_cur_card(HeapRegion::CardsPerRegion-1), 980 _cur_card_in_prt(HeapRegion::CardsPerRegion), 981 _fine_cur_prt(NULL), 982 _n_yielded_coarse(0), 983 _n_yielded_fine(0), 984 _n_yielded_sparse(0), 985 _sparse_iter(&hrrs->_other_regions._sparse_table) {} 986 987 bool HeapRegionRemSetIterator::coarse_has_next(size_t& card_index) { 988 if (_hrrs->_other_regions._n_coarse_entries == 0) return false; 989 // Go to the next card. 990 _coarse_cur_region_cur_card++; 991 // Was the last the last card in the current region? 992 if (_coarse_cur_region_cur_card == HeapRegion::CardsPerRegion) { 993 // Yes: find the next region. This may leave _coarse_cur_region_index 994 // Set to the last index, in which case there are no more coarse 995 // regions. 996 _coarse_cur_region_index = 997 (int) _coarse_map->get_next_one_offset(_coarse_cur_region_index + 1); 998 if ((size_t)_coarse_cur_region_index < _coarse_map->size()) { 999 _coarse_cur_region_cur_card = 0; 1000 HeapWord* r_bot = 1001 _g1h->region_at((uint) _coarse_cur_region_index)->bottom(); 1002 _cur_region_card_offset = _bosa->index_for(r_bot); 1003 } else { 1004 return false; 1005 } 1006 } 1007 // If we didn't return false above, then we can yield a card. 1008 card_index = _cur_region_card_offset + _coarse_cur_region_cur_card; 1009 return true; 1010 } 1011 1012 bool HeapRegionRemSetIterator::fine_has_next(size_t& card_index) { 1013 if (fine_has_next()) { 1014 _cur_card_in_prt = 1015 _fine_cur_prt->_bm.get_next_one_offset(_cur_card_in_prt + 1); 1016 } 1017 if (_cur_card_in_prt == HeapRegion::CardsPerRegion) { 1018 // _fine_cur_prt may still be NULL in case if there are not PRTs at all for 1019 // the remembered set. 1020 if (_fine_cur_prt == NULL || _fine_cur_prt->next() == NULL) { 1021 return false; 1022 } 1023 PerRegionTable* next_prt = _fine_cur_prt->next(); 1024 switch_to_prt(next_prt); 1025 _cur_card_in_prt = _fine_cur_prt->_bm.get_next_one_offset(_cur_card_in_prt + 1); 1026 } 1027 1028 card_index = _cur_region_card_offset + _cur_card_in_prt; 1029 guarantee(_cur_card_in_prt < HeapRegion::CardsPerRegion, 1030 err_msg("Card index "SIZE_FORMAT" must be within the region", _cur_card_in_prt)); 1031 return true; 1032 } 1033 1034 bool HeapRegionRemSetIterator::fine_has_next() { 1035 return _cur_card_in_prt != HeapRegion::CardsPerRegion; 1036 } 1037 1038 void HeapRegionRemSetIterator::switch_to_prt(PerRegionTable* prt) { 1039 assert(prt != NULL, "Cannot switch to NULL prt"); 1040 _fine_cur_prt = prt; 1041 1042 HeapWord* r_bot = _fine_cur_prt->hr()->bottom(); 1043 _cur_region_card_offset = _bosa->index_for(r_bot); 1044 1045 // The bitmap scan for the PRT always scans from _cur_region_cur_card + 1. 1046 // To avoid special-casing this start case, and not miss the first bitmap 1047 // entry, initialize _cur_region_cur_card with -1 instead of 0. 1048 _cur_card_in_prt = (size_t)-1; 1049 } 1050 1051 bool HeapRegionRemSetIterator::has_next(size_t& card_index) { 1052 switch (_is) { 1053 case Sparse: { 1054 if (_sparse_iter.has_next(card_index)) { 1055 _n_yielded_sparse++; 1056 return true; 1057 } 1058 // Otherwise, deliberate fall-through 1059 _is = Fine; 1060 PerRegionTable* initial_fine_prt = _hrrs->_other_regions._first_all_fine_prts; 1061 if (initial_fine_prt != NULL) { 1062 switch_to_prt(_hrrs->_other_regions._first_all_fine_prts); 1063 } 1064 } 1065 case Fine: 1066 if (fine_has_next(card_index)) { 1067 _n_yielded_fine++; 1068 return true; 1069 } 1070 // Otherwise, deliberate fall-through 1071 _is = Coarse; 1072 case Coarse: 1073 if (coarse_has_next(card_index)) { 1074 _n_yielded_coarse++; 1075 return true; 1076 } 1077 // Otherwise... 1078 break; 1079 } 1080 assert(ParallelGCThreads > 1 || 1081 n_yielded() == _hrrs->occupied(), 1082 "Should have yielded all the cards in the rem set " 1083 "(in the non-par case)."); 1084 return false; 1085 } 1086 1087 1088 1089 OopOrNarrowOopStar* HeapRegionRemSet::_recorded_oops = NULL; 1090 HeapWord** HeapRegionRemSet::_recorded_cards = NULL; 1091 HeapRegion** HeapRegionRemSet::_recorded_regions = NULL; 1092 int HeapRegionRemSet::_n_recorded = 0; 1093 1094 HeapRegionRemSet::Event* HeapRegionRemSet::_recorded_events = NULL; 1095 int* HeapRegionRemSet::_recorded_event_index = NULL; 1096 int HeapRegionRemSet::_n_recorded_events = 0; 1097 1098 void HeapRegionRemSet::record(HeapRegion* hr, OopOrNarrowOopStar f) { 1099 if (_recorded_oops == NULL) { 1100 assert(_n_recorded == 0 1101 && _recorded_cards == NULL 1102 && _recorded_regions == NULL, 1103 "Inv"); 1104 _recorded_oops = NEW_C_HEAP_ARRAY(OopOrNarrowOopStar, MaxRecorded, mtGC); 1105 _recorded_cards = NEW_C_HEAP_ARRAY(HeapWord*, MaxRecorded, mtGC); 1106 _recorded_regions = NEW_C_HEAP_ARRAY(HeapRegion*, MaxRecorded, mtGC); 1107 } 1108 if (_n_recorded == MaxRecorded) { 1109 gclog_or_tty->print_cr("Filled up 'recorded' (%d).", MaxRecorded); 1110 } else { 1111 _recorded_cards[_n_recorded] = 1112 (HeapWord*)align_size_down(uintptr_t(f), 1113 CardTableModRefBS::card_size); 1114 _recorded_oops[_n_recorded] = f; 1115 _recorded_regions[_n_recorded] = hr; 1116 _n_recorded++; 1117 } 1118 } 1119 1120 void HeapRegionRemSet::record_event(Event evnt) { 1121 if (!G1RecordHRRSEvents) return; 1122 1123 if (_recorded_events == NULL) { 1124 assert(_n_recorded_events == 0 1125 && _recorded_event_index == NULL, 1126 "Inv"); 1127 _recorded_events = NEW_C_HEAP_ARRAY(Event, MaxRecordedEvents, mtGC); 1128 _recorded_event_index = NEW_C_HEAP_ARRAY(int, MaxRecordedEvents, mtGC); 1129 } 1130 if (_n_recorded_events == MaxRecordedEvents) { 1131 gclog_or_tty->print_cr("Filled up 'recorded_events' (%d).", MaxRecordedEvents); 1132 } else { 1133 _recorded_events[_n_recorded_events] = evnt; 1134 _recorded_event_index[_n_recorded_events] = _n_recorded; 1135 _n_recorded_events++; 1136 } 1137 } 1138 1139 void HeapRegionRemSet::print_event(outputStream* str, Event evnt) { 1140 switch (evnt) { 1141 case Event_EvacStart: 1142 str->print("Evac Start"); 1143 break; 1144 case Event_EvacEnd: 1145 str->print("Evac End"); 1146 break; 1147 case Event_RSUpdateEnd: 1148 str->print("RS Update End"); 1149 break; 1150 } 1151 } 1152 1153 void HeapRegionRemSet::print_recorded() { 1154 int cur_evnt = 0; 1155 Event cur_evnt_kind; 1156 int cur_evnt_ind = 0; 1157 if (_n_recorded_events > 0) { 1158 cur_evnt_kind = _recorded_events[cur_evnt]; 1159 cur_evnt_ind = _recorded_event_index[cur_evnt]; 1160 } 1161 1162 for (int i = 0; i < _n_recorded; i++) { 1163 while (cur_evnt < _n_recorded_events && i == cur_evnt_ind) { 1164 gclog_or_tty->print("Event: "); 1165 print_event(gclog_or_tty, cur_evnt_kind); 1166 gclog_or_tty->cr(); 1167 cur_evnt++; 1168 if (cur_evnt < MaxRecordedEvents) { 1169 cur_evnt_kind = _recorded_events[cur_evnt]; 1170 cur_evnt_ind = _recorded_event_index[cur_evnt]; 1171 } 1172 } 1173 gclog_or_tty->print("Added card " PTR_FORMAT " to region [" PTR_FORMAT "...]" 1174 " for ref " PTR_FORMAT ".\n", 1175 _recorded_cards[i], _recorded_regions[i]->bottom(), 1176 _recorded_oops[i]); 1177 } 1178 } 1179 1180 void HeapRegionRemSet::reset_for_cleanup_tasks() { 1181 SparsePRT::reset_for_cleanup_tasks(); 1182 } 1183 1184 void HeapRegionRemSet::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) { 1185 _other_regions.do_cleanup_work(hrrs_cleanup_task); 1186 } 1187 1188 void 1189 HeapRegionRemSet::finish_cleanup_task(HRRSCleanupTask* hrrs_cleanup_task) { 1190 SparsePRT::finish_cleanup_task(hrrs_cleanup_task); 1191 } 1192 1193 #ifndef PRODUCT 1194 void PerRegionTable::test_fl_mem_size() { 1195 PerRegionTable* dummy = alloc(NULL); 1196 1197 size_t min_prt_size = sizeof(void*) + dummy->bm()->size_in_words() * HeapWordSize; 1198 assert(dummy->mem_size() > min_prt_size, 1199 err_msg("PerRegionTable memory usage is suspiciously small, only has "SIZE_FORMAT" bytes. " 1200 "Should be at least "SIZE_FORMAT" bytes.", dummy->mem_size(), min_prt_size)); 1201 free(dummy); 1202 guarantee(dummy->mem_size() == fl_mem_size(), "fl_mem_size() does not return the correct element size"); 1203 // try to reset the state 1204 _free_list = NULL; 1205 delete dummy; 1206 } 1207 1208 void HeapRegionRemSet::test_prt() { 1209 PerRegionTable::test_fl_mem_size(); 1210 } 1211 1212 void HeapRegionRemSet::test() { 1213 os::sleep(Thread::current(), (jlong)5000, false); 1214 G1CollectedHeap* g1h = G1CollectedHeap::heap(); 1215 1216 // Run with "-XX:G1LogRSetRegionEntries=2", so that 1 and 5 end up in same 1217 // hash bucket. 1218 HeapRegion* hr0 = g1h->region_at(0); 1219 HeapRegion* hr1 = g1h->region_at(1); 1220 HeapRegion* hr2 = g1h->region_at(5); 1221 HeapRegion* hr3 = g1h->region_at(6); 1222 HeapRegion* hr4 = g1h->region_at(7); 1223 HeapRegion* hr5 = g1h->region_at(8); 1224 1225 HeapWord* hr1_start = hr1->bottom(); 1226 HeapWord* hr1_mid = hr1_start + HeapRegion::GrainWords/2; 1227 HeapWord* hr1_last = hr1->end() - 1; 1228 1229 HeapWord* hr2_start = hr2->bottom(); 1230 HeapWord* hr2_mid = hr2_start + HeapRegion::GrainWords/2; 1231 HeapWord* hr2_last = hr2->end() - 1; 1232 1233 HeapWord* hr3_start = hr3->bottom(); 1234 HeapWord* hr3_mid = hr3_start + HeapRegion::GrainWords/2; 1235 HeapWord* hr3_last = hr3->end() - 1; 1236 1237 HeapRegionRemSet* hrrs = hr0->rem_set(); 1238 1239 // Make three references from region 0x101... 1240 hrrs->add_reference((OopOrNarrowOopStar)hr1_start); 1241 hrrs->add_reference((OopOrNarrowOopStar)hr1_mid); 1242 hrrs->add_reference((OopOrNarrowOopStar)hr1_last); 1243 1244 hrrs->add_reference((OopOrNarrowOopStar)hr2_start); 1245 hrrs->add_reference((OopOrNarrowOopStar)hr2_mid); 1246 hrrs->add_reference((OopOrNarrowOopStar)hr2_last); 1247 1248 hrrs->add_reference((OopOrNarrowOopStar)hr3_start); 1249 hrrs->add_reference((OopOrNarrowOopStar)hr3_mid); 1250 hrrs->add_reference((OopOrNarrowOopStar)hr3_last); 1251 1252 // Now cause a coarsening. 1253 hrrs->add_reference((OopOrNarrowOopStar)hr4->bottom()); 1254 hrrs->add_reference((OopOrNarrowOopStar)hr5->bottom()); 1255 1256 // Now, does iteration yield these three? 1257 HeapRegionRemSetIterator iter(hrrs); 1258 size_t sum = 0; 1259 size_t card_index; 1260 while (iter.has_next(card_index)) { 1261 HeapWord* card_start = 1262 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index); 1263 gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start); 1264 sum++; 1265 } 1266 guarantee(sum == 11 - 3 + 2048, "Failure"); 1267 guarantee(sum == hrrs->occupied(), "Failure"); 1268 } 1269 #endif