1 /* 2 * Copyright (c) 2000, 2021, 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 "classfile/classLoaderDataGraph.hpp" 27 #include "classfile/symbolTable.hpp" 28 #include "classfile/stringTable.hpp" 29 #include "classfile/vmSymbols.hpp" 30 #include "code/codeCache.hpp" 31 #include "code/icBuffer.hpp" 32 #include "compiler/oopMap.hpp" 33 #include "gc/serial/defNewGeneration.hpp" 34 #include "gc/shared/adaptiveSizePolicy.hpp" 35 #include "gc/shared/cardTableBarrierSet.hpp" 36 #include "gc/shared/cardTableRS.hpp" 37 #include "gc/shared/collectedHeap.inline.hpp" 38 #include "gc/shared/collectorCounters.hpp" 39 #include "gc/shared/gcId.hpp" 40 #include "gc/shared/gcLocker.hpp" 41 #include "gc/shared/gcPolicyCounters.hpp" 42 #include "gc/shared/gcTrace.hpp" 43 #include "gc/shared/gcTraceTime.inline.hpp" 44 #include "gc/shared/genArguments.hpp" 45 #include "gc/shared/gcVMOperations.hpp" 46 #include "gc/shared/genCollectedHeap.hpp" 47 #include "gc/shared/genOopClosures.inline.hpp" 48 #include "gc/shared/generationSpec.hpp" 49 #include "gc/shared/gcInitLogger.hpp" 50 #include "gc/shared/locationPrinter.inline.hpp" 51 #include "gc/shared/oopStorage.inline.hpp" 52 #include "gc/shared/oopStorageSet.inline.hpp" 53 #include "gc/shared/oopStorageParState.inline.hpp" 54 #include "gc/shared/scavengableNMethods.hpp" 55 #include "gc/shared/slidingForwarding.hpp" 56 #include "gc/shared/space.hpp" 57 #include "gc/shared/strongRootsScope.hpp" 58 #include "gc/shared/weakProcessor.hpp" 59 #include "gc/shared/workgroup.hpp" 60 #include "memory/iterator.hpp" 61 #include "memory/metaspaceCounters.hpp" 62 #include "memory/metaspaceUtils.hpp" 63 #include "memory/resourceArea.hpp" 64 #include "memory/universe.hpp" 65 #include "oops/oop.inline.hpp" 66 #include "runtime/biasedLocking.hpp" 67 #include "runtime/handles.hpp" 68 #include "runtime/handles.inline.hpp" 69 #include "runtime/java.hpp" 70 #include "runtime/vmThread.hpp" 71 #include "services/memoryService.hpp" 72 #include "utilities/autoRestore.hpp" 73 #include "utilities/debug.hpp" 74 #include "utilities/formatBuffer.hpp" 75 #include "utilities/macros.hpp" 76 #include "utilities/stack.inline.hpp" 77 #include "utilities/vmError.hpp" 78 #if INCLUDE_JVMCI 79 #include "jvmci/jvmci.hpp" 80 #endif 81 82 GenCollectedHeap::GenCollectedHeap(Generation::Name young, 83 Generation::Name old, 84 const char* policy_counters_name) : 85 CollectedHeap(), 86 _young_gen(NULL), 87 _old_gen(NULL), 88 _young_gen_spec(new GenerationSpec(young, 89 NewSize, 90 MaxNewSize, 91 GenAlignment)), 92 _old_gen_spec(new GenerationSpec(old, 93 OldSize, 94 MaxOldSize, 95 GenAlignment)), 96 _rem_set(NULL), 97 _soft_ref_gen_policy(), 98 _size_policy(NULL), 99 _gc_policy_counters(new GCPolicyCounters(policy_counters_name, 2, 2)), 100 _incremental_collection_failed(false), 101 _full_collections_completed(0), 102 _young_manager(NULL), 103 _old_manager(NULL) { 104 } 105 106 jint GenCollectedHeap::initialize() { 107 // While there are no constraints in the GC code that HeapWordSize 108 // be any particular value, there are multiple other areas in the 109 // system which believe this to be true (e.g. oop->object_size in some 110 // cases incorrectly returns the size in wordSize units rather than 111 // HeapWordSize). 112 guarantee(HeapWordSize == wordSize, "HeapWordSize must equal wordSize"); 113 114 // Allocate space for the heap. 115 116 ReservedHeapSpace heap_rs = allocate(HeapAlignment); 117 118 if (!heap_rs.is_reserved()) { 119 vm_shutdown_during_initialization( 120 "Could not reserve enough space for object heap"); 121 return JNI_ENOMEM; 122 } 123 124 initialize_reserved_region(heap_rs); 125 _forwarding = new SlidingForwarding(_reserved); 126 127 _rem_set = create_rem_set(heap_rs.region()); 128 _rem_set->initialize(); 129 CardTableBarrierSet *bs = new CardTableBarrierSet(_rem_set); 130 bs->initialize(); 131 BarrierSet::set_barrier_set(bs); 132 133 ReservedSpace young_rs = heap_rs.first_part(_young_gen_spec->max_size()); 134 _young_gen = _young_gen_spec->init(young_rs, rem_set()); 135 ReservedSpace old_rs = heap_rs.last_part(_young_gen_spec->max_size()); 136 137 old_rs = old_rs.first_part(_old_gen_spec->max_size()); 138 _old_gen = _old_gen_spec->init(old_rs, rem_set()); 139 140 GCInitLogger::print(); 141 142 return JNI_OK; 143 } 144 145 CardTableRS* GenCollectedHeap::create_rem_set(const MemRegion& reserved_region) { 146 return new CardTableRS(reserved_region); 147 } 148 149 void GenCollectedHeap::initialize_size_policy(size_t init_eden_size, 150 size_t init_promo_size, 151 size_t init_survivor_size) { 152 const double max_gc_pause_sec = ((double) MaxGCPauseMillis) / 1000.0; 153 _size_policy = new AdaptiveSizePolicy(init_eden_size, 154 init_promo_size, 155 init_survivor_size, 156 max_gc_pause_sec, 157 GCTimeRatio); 158 } 159 160 ReservedHeapSpace GenCollectedHeap::allocate(size_t alignment) { 161 // Now figure out the total size. 162 const size_t pageSize = UseLargePages ? os::large_page_size() : os::vm_page_size(); 163 assert(alignment % pageSize == 0, "Must be"); 164 165 // Check for overflow. 166 size_t total_reserved = _young_gen_spec->max_size() + _old_gen_spec->max_size(); 167 if (total_reserved < _young_gen_spec->max_size()) { 168 vm_exit_during_initialization("The size of the object heap + VM data exceeds " 169 "the maximum representable size"); 170 } 171 assert(total_reserved % alignment == 0, 172 "Gen size; total_reserved=" SIZE_FORMAT ", alignment=" 173 SIZE_FORMAT, total_reserved, alignment); 174 175 ReservedHeapSpace heap_rs = Universe::reserve_heap(total_reserved, alignment); 176 size_t used_page_size = heap_rs.page_size(); 177 178 os::trace_page_sizes("Heap", 179 MinHeapSize, 180 total_reserved, 181 used_page_size, 182 heap_rs.base(), 183 heap_rs.size()); 184 185 return heap_rs; 186 } 187 188 class GenIsScavengable : public BoolObjectClosure { 189 public: 190 bool do_object_b(oop obj) { 191 return GenCollectedHeap::heap()->is_in_young(obj); 192 } 193 }; 194 195 static GenIsScavengable _is_scavengable; 196 197 void GenCollectedHeap::post_initialize() { 198 CollectedHeap::post_initialize(); 199 ref_processing_init(); 200 201 DefNewGeneration* def_new_gen = (DefNewGeneration*)_young_gen; 202 203 initialize_size_policy(def_new_gen->eden()->capacity(), 204 _old_gen->capacity(), 205 def_new_gen->from()->capacity()); 206 207 MarkSweep::initialize(); 208 209 ScavengableNMethods::initialize(&_is_scavengable); 210 } 211 212 void GenCollectedHeap::ref_processing_init() { 213 _young_gen->ref_processor_init(); 214 _old_gen->ref_processor_init(); 215 } 216 217 PreGenGCValues GenCollectedHeap::get_pre_gc_values() const { 218 const DefNewGeneration* const def_new_gen = (DefNewGeneration*) young_gen(); 219 220 return PreGenGCValues(def_new_gen->used(), 221 def_new_gen->capacity(), 222 def_new_gen->eden()->used(), 223 def_new_gen->eden()->capacity(), 224 def_new_gen->from()->used(), 225 def_new_gen->from()->capacity(), 226 old_gen()->used(), 227 old_gen()->capacity()); 228 } 229 230 GenerationSpec* GenCollectedHeap::young_gen_spec() const { 231 return _young_gen_spec; 232 } 233 234 GenerationSpec* GenCollectedHeap::old_gen_spec() const { 235 return _old_gen_spec; 236 } 237 238 size_t GenCollectedHeap::capacity() const { 239 return _young_gen->capacity() + _old_gen->capacity(); 240 } 241 242 size_t GenCollectedHeap::used() const { 243 return _young_gen->used() + _old_gen->used(); 244 } 245 246 void GenCollectedHeap::save_used_regions() { 247 _old_gen->save_used_region(); 248 _young_gen->save_used_region(); 249 } 250 251 size_t GenCollectedHeap::max_capacity() const { 252 return _young_gen->max_capacity() + _old_gen->max_capacity(); 253 } 254 255 // Update the _full_collections_completed counter 256 // at the end of a stop-world full GC. 257 unsigned int GenCollectedHeap::update_full_collections_completed() { 258 assert(_full_collections_completed <= _total_full_collections, 259 "Can't complete more collections than were started"); 260 _full_collections_completed = _total_full_collections; 261 return _full_collections_completed; 262 } 263 264 // Return true if any of the following is true: 265 // . the allocation won't fit into the current young gen heap 266 // . gc locker is occupied (jni critical section) 267 // . heap memory is tight -- the most recent previous collection 268 // was a full collection because a partial collection (would 269 // have) failed and is likely to fail again 270 bool GenCollectedHeap::should_try_older_generation_allocation(size_t word_size) const { 271 size_t young_capacity = _young_gen->capacity_before_gc(); 272 return (word_size > heap_word_size(young_capacity)) 273 || GCLocker::is_active_and_needs_gc() 274 || incremental_collection_failed(); 275 } 276 277 HeapWord* GenCollectedHeap::expand_heap_and_allocate(size_t size, bool is_tlab) { 278 HeapWord* result = NULL; 279 if (_old_gen->should_allocate(size, is_tlab)) { 280 result = _old_gen->expand_and_allocate(size, is_tlab); 281 } 282 if (result == NULL) { 283 if (_young_gen->should_allocate(size, is_tlab)) { 284 result = _young_gen->expand_and_allocate(size, is_tlab); 285 } 286 } 287 assert(result == NULL || is_in_reserved(result), "result not in heap"); 288 return result; 289 } 290 291 HeapWord* GenCollectedHeap::mem_allocate_work(size_t size, 292 bool is_tlab, 293 bool* gc_overhead_limit_was_exceeded) { 294 // In general gc_overhead_limit_was_exceeded should be false so 295 // set it so here and reset it to true only if the gc time 296 // limit is being exceeded as checked below. 297 *gc_overhead_limit_was_exceeded = false; 298 299 HeapWord* result = NULL; 300 301 // Loop until the allocation is satisfied, or unsatisfied after GC. 302 for (uint try_count = 1, gclocker_stalled_count = 0; /* return or throw */; try_count += 1) { 303 304 // First allocation attempt is lock-free. 305 Generation *young = _young_gen; 306 assert(young->supports_inline_contig_alloc(), 307 "Otherwise, must do alloc within heap lock"); 308 if (young->should_allocate(size, is_tlab)) { 309 result = young->par_allocate(size, is_tlab); 310 if (result != NULL) { 311 assert(is_in_reserved(result), "result not in heap"); 312 return result; 313 } 314 } 315 uint gc_count_before; // Read inside the Heap_lock locked region. 316 { 317 MutexLocker ml(Heap_lock); 318 log_trace(gc, alloc)("GenCollectedHeap::mem_allocate_work: attempting locked slow path allocation"); 319 // Note that only large objects get a shot at being 320 // allocated in later generations. 321 bool first_only = !should_try_older_generation_allocation(size); 322 323 result = attempt_allocation(size, is_tlab, first_only); 324 if (result != NULL) { 325 assert(is_in_reserved(result), "result not in heap"); 326 return result; 327 } 328 329 if (GCLocker::is_active_and_needs_gc()) { 330 if (is_tlab) { 331 return NULL; // Caller will retry allocating individual object. 332 } 333 if (!is_maximal_no_gc()) { 334 // Try and expand heap to satisfy request. 335 result = expand_heap_and_allocate(size, is_tlab); 336 // Result could be null if we are out of space. 337 if (result != NULL) { 338 return result; 339 } 340 } 341 342 if (gclocker_stalled_count > GCLockerRetryAllocationCount) { 343 return NULL; // We didn't get to do a GC and we didn't get any memory. 344 } 345 346 // If this thread is not in a jni critical section, we stall 347 // the requestor until the critical section has cleared and 348 // GC allowed. When the critical section clears, a GC is 349 // initiated by the last thread exiting the critical section; so 350 // we retry the allocation sequence from the beginning of the loop, 351 // rather than causing more, now probably unnecessary, GC attempts. 352 JavaThread* jthr = JavaThread::current(); 353 if (!jthr->in_critical()) { 354 MutexUnlocker mul(Heap_lock); 355 // Wait for JNI critical section to be exited 356 GCLocker::stall_until_clear(); 357 gclocker_stalled_count += 1; 358 continue; 359 } else { 360 if (CheckJNICalls) { 361 fatal("Possible deadlock due to allocating while" 362 " in jni critical section"); 363 } 364 return NULL; 365 } 366 } 367 368 // Read the gc count while the heap lock is held. 369 gc_count_before = total_collections(); 370 } 371 372 VM_GenCollectForAllocation op(size, is_tlab, gc_count_before); 373 VMThread::execute(&op); 374 if (op.prologue_succeeded()) { 375 result = op.result(); 376 if (op.gc_locked()) { 377 assert(result == NULL, "must be NULL if gc_locked() is true"); 378 continue; // Retry and/or stall as necessary. 379 } 380 381 // Allocation has failed and a collection 382 // has been done. If the gc time limit was exceeded the 383 // this time, return NULL so that an out-of-memory 384 // will be thrown. Clear gc_overhead_limit_exceeded 385 // so that the overhead exceeded does not persist. 386 387 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); 388 const bool softrefs_clear = soft_ref_policy()->all_soft_refs_clear(); 389 390 if (limit_exceeded && softrefs_clear) { 391 *gc_overhead_limit_was_exceeded = true; 392 size_policy()->set_gc_overhead_limit_exceeded(false); 393 if (op.result() != NULL) { 394 CollectedHeap::fill_with_object(op.result(), size); 395 } 396 return NULL; 397 } 398 assert(result == NULL || is_in_reserved(result), 399 "result not in heap"); 400 return result; 401 } 402 403 // Give a warning if we seem to be looping forever. 404 if ((QueuedAllocationWarningCount > 0) && 405 (try_count % QueuedAllocationWarningCount == 0)) { 406 log_warning(gc, ergo)("GenCollectedHeap::mem_allocate_work retries %d times," 407 " size=" SIZE_FORMAT " %s", try_count, size, is_tlab ? "(TLAB)" : ""); 408 } 409 } 410 } 411 412 HeapWord* GenCollectedHeap::attempt_allocation(size_t size, 413 bool is_tlab, 414 bool first_only) { 415 HeapWord* res = NULL; 416 417 if (_young_gen->should_allocate(size, is_tlab)) { 418 res = _young_gen->allocate(size, is_tlab); 419 if (res != NULL || first_only) { 420 return res; 421 } 422 } 423 424 if (_old_gen->should_allocate(size, is_tlab)) { 425 res = _old_gen->allocate(size, is_tlab); 426 } 427 428 return res; 429 } 430 431 HeapWord* GenCollectedHeap::mem_allocate(size_t size, 432 bool* gc_overhead_limit_was_exceeded) { 433 return mem_allocate_work(size, 434 false /* is_tlab */, 435 gc_overhead_limit_was_exceeded); 436 } 437 438 bool GenCollectedHeap::must_clear_all_soft_refs() { 439 return _gc_cause == GCCause::_metadata_GC_clear_soft_refs || 440 _gc_cause == GCCause::_wb_full_gc; 441 } 442 443 void GenCollectedHeap::collect_generation(Generation* gen, bool full, size_t size, 444 bool is_tlab, bool run_verification, bool clear_soft_refs, 445 bool restore_marks_for_biased_locking) { 446 FormatBuffer<> title("Collect gen: %s", gen->short_name()); 447 GCTraceTime(Trace, gc, phases) t1(title); 448 TraceCollectorStats tcs(gen->counters()); 449 TraceMemoryManagerStats tmms(gen->gc_manager(), gc_cause()); 450 451 gen->stat_record()->invocations++; 452 gen->stat_record()->accumulated_time.start(); 453 454 // Must be done anew before each collection because 455 // a previous collection will do mangling and will 456 // change top of some spaces. 457 record_gen_tops_before_GC(); 458 459 log_trace(gc)("%s invoke=%d size=" SIZE_FORMAT, heap()->is_young_gen(gen) ? "Young" : "Old", gen->stat_record()->invocations, size * HeapWordSize); 460 461 if (run_verification && VerifyBeforeGC) { 462 Universe::verify("Before GC"); 463 } 464 COMPILER2_OR_JVMCI_PRESENT(DerivedPointerTable::clear()); 465 466 if (restore_marks_for_biased_locking) { 467 // We perform this mark word preservation work lazily 468 // because it's only at this point that we know whether we 469 // absolutely have to do it; we want to avoid doing it for 470 // scavenge-only collections where it's unnecessary 471 BiasedLocking::preserve_marks(); 472 } 473 474 // Do collection work 475 { 476 // Note on ref discovery: For what appear to be historical reasons, 477 // GCH enables and disabled (by enqueing) refs discovery. 478 // In the future this should be moved into the generation's 479 // collect method so that ref discovery and enqueueing concerns 480 // are local to a generation. The collect method could return 481 // an appropriate indication in the case that notification on 482 // the ref lock was needed. This will make the treatment of 483 // weak refs more uniform (and indeed remove such concerns 484 // from GCH). XXX 485 486 save_marks(); // save marks for all gens 487 // We want to discover references, but not process them yet. 488 // This mode is disabled in process_discovered_references if the 489 // generation does some collection work, or in 490 // enqueue_discovered_references if the generation returns 491 // without doing any work. 492 ReferenceProcessor* rp = gen->ref_processor(); 493 // If the discovery of ("weak") refs in this generation is 494 // atomic wrt other collectors in this configuration, we 495 // are guaranteed to have empty discovered ref lists. 496 if (rp->discovery_is_atomic()) { 497 rp->enable_discovery(); 498 rp->setup_policy(clear_soft_refs); 499 } else { 500 // collect() below will enable discovery as appropriate 501 } 502 gen->collect(full, clear_soft_refs, size, is_tlab); 503 if (!rp->enqueuing_is_done()) { 504 rp->disable_discovery(); 505 } else { 506 rp->set_enqueuing_is_done(false); 507 } 508 rp->verify_no_references_recorded(); 509 } 510 511 COMPILER2_OR_JVMCI_PRESENT(DerivedPointerTable::update_pointers()); 512 513 gen->stat_record()->accumulated_time.stop(); 514 515 update_gc_stats(gen, full); 516 517 if (run_verification && VerifyAfterGC) { 518 Universe::verify("After GC"); 519 } 520 } 521 522 void GenCollectedHeap::do_collection(bool full, 523 bool clear_all_soft_refs, 524 size_t size, 525 bool is_tlab, 526 GenerationType max_generation) { 527 ResourceMark rm; 528 DEBUG_ONLY(Thread* my_thread = Thread::current();) 529 530 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); 531 assert(my_thread->is_VM_thread(), "only VM thread"); 532 assert(Heap_lock->is_locked(), 533 "the requesting thread should have the Heap_lock"); 534 guarantee(!is_gc_active(), "collection is not reentrant"); 535 536 if (GCLocker::check_active_before_gc()) { 537 return; // GC is disabled (e.g. JNI GetXXXCritical operation) 538 } 539 540 const bool do_clear_all_soft_refs = clear_all_soft_refs || 541 soft_ref_policy()->should_clear_all_soft_refs(); 542 543 ClearedAllSoftRefs casr(do_clear_all_soft_refs, soft_ref_policy()); 544 545 AutoModifyRestore<bool> temporarily(_is_gc_active, true); 546 547 bool complete = full && (max_generation == OldGen); 548 bool old_collects_young = complete && !ScavengeBeforeFullGC; 549 bool do_young_collection = !old_collects_young && _young_gen->should_collect(full, size, is_tlab); 550 551 const PreGenGCValues pre_gc_values = get_pre_gc_values(); 552 553 bool run_verification = total_collections() >= VerifyGCStartAt; 554 bool prepared_for_verification = false; 555 bool do_full_collection = false; 556 557 if (do_young_collection) { 558 GCIdMark gc_id_mark; 559 GCTraceCPUTime tcpu; 560 GCTraceTime(Info, gc) t("Pause Young", NULL, gc_cause(), true); 561 562 print_heap_before_gc(); 563 564 if (run_verification && VerifyGCLevel <= 0 && VerifyBeforeGC) { 565 prepare_for_verify(); 566 prepared_for_verification = true; 567 } 568 569 gc_prologue(complete); 570 increment_total_collections(complete); 571 572 collect_generation(_young_gen, 573 full, 574 size, 575 is_tlab, 576 run_verification && VerifyGCLevel <= 0, 577 do_clear_all_soft_refs, 578 false); 579 580 if (size > 0 && (!is_tlab || _young_gen->supports_tlab_allocation()) && 581 size * HeapWordSize <= _young_gen->unsafe_max_alloc_nogc()) { 582 // Allocation request was met by young GC. 583 size = 0; 584 } 585 586 // Ask if young collection is enough. If so, do the final steps for young collection, 587 // and fallthrough to the end. 588 do_full_collection = should_do_full_collection(size, full, is_tlab, max_generation); 589 if (!do_full_collection) { 590 // Adjust generation sizes. 591 _young_gen->compute_new_size(); 592 593 print_heap_change(pre_gc_values); 594 595 // Track memory usage and detect low memory after GC finishes 596 MemoryService::track_memory_usage(); 597 598 gc_epilogue(complete); 599 } 600 601 print_heap_after_gc(); 602 603 } else { 604 // No young collection, ask if we need to perform Full collection. 605 do_full_collection = should_do_full_collection(size, full, is_tlab, max_generation); 606 } 607 608 if (do_full_collection) { 609 GCIdMark gc_id_mark; 610 GCTraceCPUTime tcpu; 611 GCTraceTime(Info, gc) t("Pause Full", NULL, gc_cause(), true); 612 613 print_heap_before_gc(); 614 615 if (!prepared_for_verification && run_verification && 616 VerifyGCLevel <= 1 && VerifyBeforeGC) { 617 prepare_for_verify(); 618 } 619 620 if (!do_young_collection) { 621 gc_prologue(complete); 622 increment_total_collections(complete); 623 } 624 625 // Accounting quirk: total full collections would be incremented when "complete" 626 // is set, by calling increment_total_collections above. However, we also need to 627 // account Full collections that had "complete" unset. 628 if (!complete) { 629 increment_total_full_collections(); 630 } 631 632 collect_generation(_old_gen, 633 full, 634 size, 635 is_tlab, 636 run_verification && VerifyGCLevel <= 1, 637 do_clear_all_soft_refs, 638 true); 639 640 // Adjust generation sizes. 641 _old_gen->compute_new_size(); 642 _young_gen->compute_new_size(); 643 644 // Delete metaspaces for unloaded class loaders and clean up loader_data graph 645 ClassLoaderDataGraph::purge(/*at_safepoint*/true); 646 DEBUG_ONLY(MetaspaceUtils::verify();) 647 // Resize the metaspace capacity after full collections 648 MetaspaceGC::compute_new_size(); 649 update_full_collections_completed(); 650 651 print_heap_change(pre_gc_values); 652 653 // Track memory usage and detect low memory after GC finishes 654 MemoryService::track_memory_usage(); 655 656 // Need to tell the epilogue code we are done with Full GC, regardless what was 657 // the initial value for "complete" flag. 658 gc_epilogue(true); 659 660 BiasedLocking::restore_marks(); 661 662 print_heap_after_gc(); 663 } 664 } 665 666 bool GenCollectedHeap::should_do_full_collection(size_t size, bool full, bool is_tlab, 667 GenCollectedHeap::GenerationType max_gen) const { 668 return max_gen == OldGen && _old_gen->should_collect(full, size, is_tlab); 669 } 670 671 void GenCollectedHeap::register_nmethod(nmethod* nm) { 672 ScavengableNMethods::register_nmethod(nm); 673 } 674 675 void GenCollectedHeap::unregister_nmethod(nmethod* nm) { 676 ScavengableNMethods::unregister_nmethod(nm); 677 } 678 679 void GenCollectedHeap::verify_nmethod(nmethod* nm) { 680 ScavengableNMethods::verify_nmethod(nm); 681 } 682 683 void GenCollectedHeap::flush_nmethod(nmethod* nm) { 684 // Do nothing. 685 } 686 687 void GenCollectedHeap::prune_scavengable_nmethods() { 688 ScavengableNMethods::prune_nmethods(); 689 } 690 691 HeapWord* GenCollectedHeap::satisfy_failed_allocation(size_t size, bool is_tlab) { 692 GCCauseSetter x(this, GCCause::_allocation_failure); 693 HeapWord* result = NULL; 694 695 assert(size != 0, "Precondition violated"); 696 if (GCLocker::is_active_and_needs_gc()) { 697 // GC locker is active; instead of a collection we will attempt 698 // to expand the heap, if there's room for expansion. 699 if (!is_maximal_no_gc()) { 700 result = expand_heap_and_allocate(size, is_tlab); 701 } 702 return result; // Could be null if we are out of space. 703 } else if (!incremental_collection_will_fail(false /* don't consult_young */)) { 704 // Do an incremental collection. 705 do_collection(false, // full 706 false, // clear_all_soft_refs 707 size, // size 708 is_tlab, // is_tlab 709 GenCollectedHeap::OldGen); // max_generation 710 } else { 711 log_trace(gc)(" :: Trying full because partial may fail :: "); 712 // Try a full collection; see delta for bug id 6266275 713 // for the original code and why this has been simplified 714 // with from-space allocation criteria modified and 715 // such allocation moved out of the safepoint path. 716 do_collection(true, // full 717 false, // clear_all_soft_refs 718 size, // size 719 is_tlab, // is_tlab 720 GenCollectedHeap::OldGen); // max_generation 721 } 722 723 result = attempt_allocation(size, is_tlab, false /*first_only*/); 724 725 if (result != NULL) { 726 assert(is_in_reserved(result), "result not in heap"); 727 return result; 728 } 729 730 // OK, collection failed, try expansion. 731 result = expand_heap_and_allocate(size, is_tlab); 732 if (result != NULL) { 733 return result; 734 } 735 736 // If we reach this point, we're really out of memory. Try every trick 737 // we can to reclaim memory. Force collection of soft references. Force 738 // a complete compaction of the heap. Any additional methods for finding 739 // free memory should be here, especially if they are expensive. If this 740 // attempt fails, an OOM exception will be thrown. 741 { 742 UIntFlagSetting flag_change(MarkSweepAlwaysCompactCount, 1); // Make sure the heap is fully compacted 743 744 do_collection(true, // full 745 true, // clear_all_soft_refs 746 size, // size 747 is_tlab, // is_tlab 748 GenCollectedHeap::OldGen); // max_generation 749 } 750 751 result = attempt_allocation(size, is_tlab, false /* first_only */); 752 if (result != NULL) { 753 assert(is_in_reserved(result), "result not in heap"); 754 return result; 755 } 756 757 assert(!soft_ref_policy()->should_clear_all_soft_refs(), 758 "Flag should have been handled and cleared prior to this point"); 759 760 // What else? We might try synchronous finalization later. If the total 761 // space available is large enough for the allocation, then a more 762 // complete compaction phase than we've tried so far might be 763 // appropriate. 764 return NULL; 765 } 766 767 #ifdef ASSERT 768 class AssertNonScavengableClosure: public OopClosure { 769 public: 770 virtual void do_oop(oop* p) { 771 assert(!GenCollectedHeap::heap()->is_in_partial_collection(*p), 772 "Referent should not be scavengable."); } 773 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 774 }; 775 static AssertNonScavengableClosure assert_is_non_scavengable_closure; 776 #endif 777 778 void GenCollectedHeap::process_roots(ScanningOption so, 779 OopClosure* strong_roots, 780 CLDClosure* strong_cld_closure, 781 CLDClosure* weak_cld_closure, 782 CodeBlobToOopClosure* code_roots) { 783 // General roots. 784 assert(code_roots != NULL, "code root closure should always be set"); 785 786 ClassLoaderDataGraph::roots_cld_do(strong_cld_closure, weak_cld_closure); 787 788 // Only process code roots from thread stacks if we aren't visiting the entire CodeCache anyway 789 CodeBlobToOopClosure* roots_from_code_p = (so & SO_AllCodeCache) ? NULL : code_roots; 790 791 Threads::oops_do(strong_roots, roots_from_code_p); 792 793 OopStorageSet::strong_oops_do(strong_roots); 794 795 if (so & SO_ScavengeCodeCache) { 796 assert(code_roots != NULL, "must supply closure for code cache"); 797 798 // We only visit parts of the CodeCache when scavenging. 799 ScavengableNMethods::nmethods_do(code_roots); 800 } 801 if (so & SO_AllCodeCache) { 802 assert(code_roots != NULL, "must supply closure for code cache"); 803 804 // CMSCollector uses this to do intermediate-strength collections. 805 // We scan the entire code cache, since CodeCache::do_unloading is not called. 806 CodeCache::blobs_do(code_roots); 807 } 808 // Verify that the code cache contents are not subject to 809 // movement by a scavenging collection. 810 DEBUG_ONLY(CodeBlobToOopClosure assert_code_is_non_scavengable(&assert_is_non_scavengable_closure, !CodeBlobToOopClosure::FixRelocations)); 811 DEBUG_ONLY(ScavengableNMethods::asserted_non_scavengable_nmethods_do(&assert_code_is_non_scavengable)); 812 } 813 814 void GenCollectedHeap::full_process_roots(bool is_adjust_phase, 815 ScanningOption so, 816 bool only_strong_roots, 817 OopClosure* root_closure, 818 CLDClosure* cld_closure) { 819 MarkingCodeBlobClosure mark_code_closure(root_closure, is_adjust_phase); 820 CLDClosure* weak_cld_closure = only_strong_roots ? NULL : cld_closure; 821 822 process_roots(so, root_closure, cld_closure, weak_cld_closure, &mark_code_closure); 823 } 824 825 void GenCollectedHeap::gen_process_weak_roots(OopClosure* root_closure) { 826 WeakProcessor::oops_do(root_closure); 827 _young_gen->ref_processor()->weak_oops_do(root_closure); 828 _old_gen->ref_processor()->weak_oops_do(root_closure); 829 } 830 831 bool GenCollectedHeap::no_allocs_since_save_marks() { 832 return _young_gen->no_allocs_since_save_marks() && 833 _old_gen->no_allocs_since_save_marks(); 834 } 835 836 bool GenCollectedHeap::supports_inline_contig_alloc() const { 837 return _young_gen->supports_inline_contig_alloc(); 838 } 839 840 HeapWord* volatile* GenCollectedHeap::top_addr() const { 841 return _young_gen->top_addr(); 842 } 843 844 HeapWord** GenCollectedHeap::end_addr() const { 845 return _young_gen->end_addr(); 846 } 847 848 // public collection interfaces 849 850 void GenCollectedHeap::collect(GCCause::Cause cause) { 851 if ((cause == GCCause::_wb_young_gc) || 852 (cause == GCCause::_gc_locker)) { 853 // Young collection for WhiteBox or GCLocker. 854 collect(cause, YoungGen); 855 } else { 856 #ifdef ASSERT 857 if (cause == GCCause::_scavenge_alot) { 858 // Young collection only. 859 collect(cause, YoungGen); 860 } else { 861 // Stop-the-world full collection. 862 collect(cause, OldGen); 863 } 864 #else 865 // Stop-the-world full collection. 866 collect(cause, OldGen); 867 #endif 868 } 869 } 870 871 void GenCollectedHeap::collect(GCCause::Cause cause, GenerationType max_generation) { 872 // The caller doesn't have the Heap_lock 873 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 874 MutexLocker ml(Heap_lock); 875 collect_locked(cause, max_generation); 876 } 877 878 void GenCollectedHeap::collect_locked(GCCause::Cause cause) { 879 // The caller has the Heap_lock 880 assert(Heap_lock->owned_by_self(), "this thread should own the Heap_lock"); 881 collect_locked(cause, OldGen); 882 } 883 884 // this is the private collection interface 885 // The Heap_lock is expected to be held on entry. 886 887 void GenCollectedHeap::collect_locked(GCCause::Cause cause, GenerationType max_generation) { 888 // Read the GC count while holding the Heap_lock 889 unsigned int gc_count_before = total_collections(); 890 unsigned int full_gc_count_before = total_full_collections(); 891 892 if (GCLocker::should_discard(cause, gc_count_before)) { 893 return; 894 } 895 896 { 897 MutexUnlocker mu(Heap_lock); // give up heap lock, execute gets it back 898 VM_GenCollectFull op(gc_count_before, full_gc_count_before, 899 cause, max_generation); 900 VMThread::execute(&op); 901 } 902 } 903 904 void GenCollectedHeap::do_full_collection(bool clear_all_soft_refs) { 905 do_full_collection(clear_all_soft_refs, OldGen); 906 } 907 908 void GenCollectedHeap::do_full_collection(bool clear_all_soft_refs, 909 GenerationType last_generation) { 910 do_collection(true, // full 911 clear_all_soft_refs, // clear_all_soft_refs 912 0, // size 913 false, // is_tlab 914 last_generation); // last_generation 915 // Hack XXX FIX ME !!! 916 // A scavenge may not have been attempted, or may have 917 // been attempted and failed, because the old gen was too full 918 if (gc_cause() == GCCause::_gc_locker && incremental_collection_failed()) { 919 log_debug(gc, jni)("GC locker: Trying a full collection because scavenge failed"); 920 // This time allow the old gen to be collected as well 921 do_collection(true, // full 922 clear_all_soft_refs, // clear_all_soft_refs 923 0, // size 924 false, // is_tlab 925 OldGen); // last_generation 926 } 927 } 928 929 bool GenCollectedHeap::is_in_young(oop p) { 930 bool result = cast_from_oop<HeapWord*>(p) < _old_gen->reserved().start(); 931 assert(result == _young_gen->is_in_reserved(p), 932 "incorrect test - result=%d, p=" INTPTR_FORMAT, result, p2i((void*)p)); 933 return result; 934 } 935 936 // Returns "TRUE" iff "p" points into the committed areas of the heap. 937 bool GenCollectedHeap::is_in(const void* p) const { 938 return _young_gen->is_in(p) || _old_gen->is_in(p); 939 } 940 941 #ifdef ASSERT 942 // Don't implement this by using is_in_young(). This method is used 943 // in some cases to check that is_in_young() is correct. 944 bool GenCollectedHeap::is_in_partial_collection(const void* p) { 945 assert(is_in_reserved(p) || p == NULL, 946 "Does not work if address is non-null and outside of the heap"); 947 return p < _young_gen->reserved().end() && p != NULL; 948 } 949 #endif 950 951 void GenCollectedHeap::oop_iterate(OopIterateClosure* cl) { 952 _young_gen->oop_iterate(cl); 953 _old_gen->oop_iterate(cl); 954 } 955 956 void GenCollectedHeap::object_iterate(ObjectClosure* cl) { 957 _young_gen->object_iterate(cl); 958 _old_gen->object_iterate(cl); 959 } 960 961 Space* GenCollectedHeap::space_containing(const void* addr) const { 962 Space* res = _young_gen->space_containing(addr); 963 if (res != NULL) { 964 return res; 965 } 966 res = _old_gen->space_containing(addr); 967 assert(res != NULL, "Could not find containing space"); 968 return res; 969 } 970 971 HeapWord* GenCollectedHeap::block_start(const void* addr) const { 972 assert(is_in_reserved(addr), "block_start of address outside of heap"); 973 if (_young_gen->is_in_reserved(addr)) { 974 assert(_young_gen->is_in(addr), "addr should be in allocated part of generation"); 975 return _young_gen->block_start(addr); 976 } 977 978 assert(_old_gen->is_in_reserved(addr), "Some generation should contain the address"); 979 assert(_old_gen->is_in(addr), "addr should be in allocated part of generation"); 980 return _old_gen->block_start(addr); 981 } 982 983 bool GenCollectedHeap::block_is_obj(const HeapWord* addr) const { 984 assert(is_in_reserved(addr), "block_is_obj of address outside of heap"); 985 assert(block_start(addr) == addr, "addr must be a block start"); 986 if (_young_gen->is_in_reserved(addr)) { 987 return _young_gen->block_is_obj(addr); 988 } 989 990 assert(_old_gen->is_in_reserved(addr), "Some generation should contain the address"); 991 return _old_gen->block_is_obj(addr); 992 } 993 994 size_t GenCollectedHeap::tlab_capacity(Thread* thr) const { 995 assert(!_old_gen->supports_tlab_allocation(), "Old gen supports TLAB allocation?!"); 996 assert(_young_gen->supports_tlab_allocation(), "Young gen doesn't support TLAB allocation?!"); 997 return _young_gen->tlab_capacity(); 998 } 999 1000 size_t GenCollectedHeap::tlab_used(Thread* thr) const { 1001 assert(!_old_gen->supports_tlab_allocation(), "Old gen supports TLAB allocation?!"); 1002 assert(_young_gen->supports_tlab_allocation(), "Young gen doesn't support TLAB allocation?!"); 1003 return _young_gen->tlab_used(); 1004 } 1005 1006 size_t GenCollectedHeap::unsafe_max_tlab_alloc(Thread* thr) const { 1007 assert(!_old_gen->supports_tlab_allocation(), "Old gen supports TLAB allocation?!"); 1008 assert(_young_gen->supports_tlab_allocation(), "Young gen doesn't support TLAB allocation?!"); 1009 return _young_gen->unsafe_max_tlab_alloc(); 1010 } 1011 1012 HeapWord* GenCollectedHeap::allocate_new_tlab(size_t min_size, 1013 size_t requested_size, 1014 size_t* actual_size) { 1015 bool gc_overhead_limit_was_exceeded; 1016 HeapWord* result = mem_allocate_work(requested_size /* size */, 1017 true /* is_tlab */, 1018 &gc_overhead_limit_was_exceeded); 1019 if (result != NULL) { 1020 *actual_size = requested_size; 1021 } 1022 1023 return result; 1024 } 1025 1026 // Requires "*prev_ptr" to be non-NULL. Deletes and a block of minimal size 1027 // from the list headed by "*prev_ptr". 1028 static ScratchBlock *removeSmallestScratch(ScratchBlock **prev_ptr) { 1029 bool first = true; 1030 size_t min_size = 0; // "first" makes this conceptually infinite. 1031 ScratchBlock **smallest_ptr, *smallest; 1032 ScratchBlock *cur = *prev_ptr; 1033 while (cur) { 1034 assert(*prev_ptr == cur, "just checking"); 1035 if (first || cur->num_words < min_size) { 1036 smallest_ptr = prev_ptr; 1037 smallest = cur; 1038 min_size = smallest->num_words; 1039 first = false; 1040 } 1041 prev_ptr = &cur->next; 1042 cur = cur->next; 1043 } 1044 smallest = *smallest_ptr; 1045 *smallest_ptr = smallest->next; 1046 return smallest; 1047 } 1048 1049 // Sort the scratch block list headed by res into decreasing size order, 1050 // and set "res" to the result. 1051 static void sort_scratch_list(ScratchBlock*& list) { 1052 ScratchBlock* sorted = NULL; 1053 ScratchBlock* unsorted = list; 1054 while (unsorted) { 1055 ScratchBlock *smallest = removeSmallestScratch(&unsorted); 1056 smallest->next = sorted; 1057 sorted = smallest; 1058 } 1059 list = sorted; 1060 } 1061 1062 ScratchBlock* GenCollectedHeap::gather_scratch(Generation* requestor, 1063 size_t max_alloc_words) { 1064 ScratchBlock* res = NULL; 1065 _young_gen->contribute_scratch(res, requestor, max_alloc_words); 1066 _old_gen->contribute_scratch(res, requestor, max_alloc_words); 1067 sort_scratch_list(res); 1068 return res; 1069 } 1070 1071 void GenCollectedHeap::release_scratch() { 1072 _young_gen->reset_scratch(); 1073 _old_gen->reset_scratch(); 1074 } 1075 1076 class GenPrepareForVerifyClosure: public GenCollectedHeap::GenClosure { 1077 void do_generation(Generation* gen) { 1078 gen->prepare_for_verify(); 1079 } 1080 }; 1081 1082 void GenCollectedHeap::prepare_for_verify() { 1083 ensure_parsability(false); // no need to retire TLABs 1084 GenPrepareForVerifyClosure blk; 1085 generation_iterate(&blk, false); 1086 } 1087 1088 void GenCollectedHeap::generation_iterate(GenClosure* cl, 1089 bool old_to_young) { 1090 if (old_to_young) { 1091 cl->do_generation(_old_gen); 1092 cl->do_generation(_young_gen); 1093 } else { 1094 cl->do_generation(_young_gen); 1095 cl->do_generation(_old_gen); 1096 } 1097 } 1098 1099 bool GenCollectedHeap::is_maximal_no_gc() const { 1100 return _young_gen->is_maximal_no_gc() && _old_gen->is_maximal_no_gc(); 1101 } 1102 1103 void GenCollectedHeap::save_marks() { 1104 _young_gen->save_marks(); 1105 _old_gen->save_marks(); 1106 } 1107 1108 GenCollectedHeap* GenCollectedHeap::heap() { 1109 // SerialHeap is the only subtype of GenCollectedHeap. 1110 return named_heap<GenCollectedHeap>(CollectedHeap::Serial); 1111 } 1112 1113 #if INCLUDE_SERIALGC 1114 void GenCollectedHeap::prepare_for_compaction() { 1115 // Start by compacting into same gen. 1116 CompactPoint cp(_old_gen); 1117 _forwarding->clear(); 1118 _old_gen->prepare_for_compaction(&cp); 1119 _young_gen->prepare_for_compaction(&cp); 1120 } 1121 #endif // INCLUDE_SERIALGC 1122 1123 void GenCollectedHeap::verify(VerifyOption option /* ignored */) { 1124 log_debug(gc, verify)("%s", _old_gen->name()); 1125 _old_gen->verify(); 1126 1127 log_debug(gc, verify)("%s", _old_gen->name()); 1128 _young_gen->verify(); 1129 1130 log_debug(gc, verify)("RemSet"); 1131 rem_set()->verify(); 1132 } 1133 1134 void GenCollectedHeap::print_on(outputStream* st) const { 1135 if (_young_gen != NULL) { 1136 _young_gen->print_on(st); 1137 } 1138 if (_old_gen != NULL) { 1139 _old_gen->print_on(st); 1140 } 1141 MetaspaceUtils::print_on(st); 1142 } 1143 1144 void GenCollectedHeap::gc_threads_do(ThreadClosure* tc) const { 1145 } 1146 1147 bool GenCollectedHeap::print_location(outputStream* st, void* addr) const { 1148 return BlockLocationPrinter<GenCollectedHeap>::print_location(st, addr); 1149 } 1150 1151 void GenCollectedHeap::print_tracing_info() const { 1152 if (log_is_enabled(Debug, gc, heap, exit)) { 1153 LogStreamHandle(Debug, gc, heap, exit) lsh; 1154 _young_gen->print_summary_info_on(&lsh); 1155 _old_gen->print_summary_info_on(&lsh); 1156 } 1157 } 1158 1159 void GenCollectedHeap::print_heap_change(const PreGenGCValues& pre_gc_values) const { 1160 const DefNewGeneration* const def_new_gen = (DefNewGeneration*) young_gen(); 1161 1162 log_info(gc, heap)(HEAP_CHANGE_FORMAT" " 1163 HEAP_CHANGE_FORMAT" " 1164 HEAP_CHANGE_FORMAT, 1165 HEAP_CHANGE_FORMAT_ARGS(def_new_gen->short_name(), 1166 pre_gc_values.young_gen_used(), 1167 pre_gc_values.young_gen_capacity(), 1168 def_new_gen->used(), 1169 def_new_gen->capacity()), 1170 HEAP_CHANGE_FORMAT_ARGS("Eden", 1171 pre_gc_values.eden_used(), 1172 pre_gc_values.eden_capacity(), 1173 def_new_gen->eden()->used(), 1174 def_new_gen->eden()->capacity()), 1175 HEAP_CHANGE_FORMAT_ARGS("From", 1176 pre_gc_values.from_used(), 1177 pre_gc_values.from_capacity(), 1178 def_new_gen->from()->used(), 1179 def_new_gen->from()->capacity())); 1180 log_info(gc, heap)(HEAP_CHANGE_FORMAT, 1181 HEAP_CHANGE_FORMAT_ARGS(old_gen()->short_name(), 1182 pre_gc_values.old_gen_used(), 1183 pre_gc_values.old_gen_capacity(), 1184 old_gen()->used(), 1185 old_gen()->capacity())); 1186 MetaspaceUtils::print_metaspace_change(pre_gc_values.metaspace_sizes()); 1187 } 1188 1189 class GenGCPrologueClosure: public GenCollectedHeap::GenClosure { 1190 private: 1191 bool _full; 1192 public: 1193 void do_generation(Generation* gen) { 1194 gen->gc_prologue(_full); 1195 } 1196 GenGCPrologueClosure(bool full) : _full(full) {}; 1197 }; 1198 1199 void GenCollectedHeap::gc_prologue(bool full) { 1200 assert(InlineCacheBuffer::is_empty(), "should have cleaned up ICBuffer"); 1201 1202 // Fill TLAB's and such 1203 ensure_parsability(true); // retire TLABs 1204 1205 // Walk generations 1206 GenGCPrologueClosure blk(full); 1207 generation_iterate(&blk, false); // not old-to-young. 1208 }; 1209 1210 class GenGCEpilogueClosure: public GenCollectedHeap::GenClosure { 1211 private: 1212 bool _full; 1213 public: 1214 void do_generation(Generation* gen) { 1215 gen->gc_epilogue(_full); 1216 } 1217 GenGCEpilogueClosure(bool full) : _full(full) {}; 1218 }; 1219 1220 void GenCollectedHeap::gc_epilogue(bool full) { 1221 #if COMPILER2_OR_JVMCI 1222 assert(DerivedPointerTable::is_empty(), "derived pointer present"); 1223 size_t actual_gap = pointer_delta((HeapWord*) (max_uintx-3), *(end_addr())); 1224 guarantee(!CompilerConfig::is_c2_or_jvmci_compiler_enabled() || actual_gap > (size_t)FastAllocateSizeLimit, "inline allocation wraps"); 1225 #endif // COMPILER2_OR_JVMCI 1226 1227 resize_all_tlabs(); 1228 1229 GenGCEpilogueClosure blk(full); 1230 generation_iterate(&blk, false); // not old-to-young. 1231 1232 MetaspaceCounters::update_performance_counters(); 1233 }; 1234 1235 #ifndef PRODUCT 1236 class GenGCSaveTopsBeforeGCClosure: public GenCollectedHeap::GenClosure { 1237 private: 1238 public: 1239 void do_generation(Generation* gen) { 1240 gen->record_spaces_top(); 1241 } 1242 }; 1243 1244 void GenCollectedHeap::record_gen_tops_before_GC() { 1245 if (ZapUnusedHeapArea) { 1246 GenGCSaveTopsBeforeGCClosure blk; 1247 generation_iterate(&blk, false); // not old-to-young. 1248 } 1249 } 1250 #endif // not PRODUCT 1251 1252 class GenEnsureParsabilityClosure: public GenCollectedHeap::GenClosure { 1253 public: 1254 void do_generation(Generation* gen) { 1255 gen->ensure_parsability(); 1256 } 1257 }; 1258 1259 void GenCollectedHeap::ensure_parsability(bool retire_tlabs) { 1260 CollectedHeap::ensure_parsability(retire_tlabs); 1261 GenEnsureParsabilityClosure ep_cl; 1262 generation_iterate(&ep_cl, false); 1263 } 1264 1265 oop GenCollectedHeap::handle_failed_promotion(Generation* old_gen, 1266 oop obj, 1267 size_t obj_size) { 1268 guarantee(old_gen == _old_gen, "We only get here with an old generation"); 1269 assert(obj_size == (size_t)obj->size(), "bad obj_size passed in"); 1270 HeapWord* result = NULL; 1271 1272 result = old_gen->expand_and_allocate(obj_size, false); 1273 1274 if (result != NULL) { 1275 Copy::aligned_disjoint_words(cast_from_oop<HeapWord*>(obj), result, obj_size); 1276 } 1277 return cast_to_oop(result); 1278 }