1 /* 2 * Copyright (c) 2013, 2019, Red Hat, Inc. All rights reserved. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 * 22 */ 23 24 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_HPP 25 #define SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_HPP 26 27 #include "gc/shared/markBitMap.hpp" 28 #include "gc/shared/softRefPolicy.hpp" 29 #include "gc/shared/collectedHeap.hpp" 30 #include "gc/shenandoah/shenandoahAsserts.hpp" 31 #include "gc/shenandoah/shenandoahAllocRequest.hpp" 32 #include "gc/shenandoah/shenandoahLock.hpp" 33 #include "gc/shenandoah/shenandoahEvacOOMHandler.hpp" 34 #include "gc/shenandoah/shenandoahSharedVariables.hpp" 35 #include "services/memoryManager.hpp" 36 37 class ConcurrentGCTimer; 38 class ReferenceProcessor; 39 class ShenandoahAllocTracker; 40 class ShenandoahCollectorPolicy; 41 class ShenandoahControlThread; 42 class ShenandoahGCSession; 43 class ShenandoahGCStateResetter; 44 class ShenandoahHeuristics; 45 class ShenandoahMarkingContext; 46 class ShenandoahMode; 47 class ShenandoahPhaseTimings; 48 class ShenandoahHeap; 49 class ShenandoahHeapRegion; 50 class ShenandoahHeapRegionClosure; 51 class ShenandoahCollectionSet; 52 class ShenandoahFreeSet; 53 class ShenandoahConcurrentMark; 54 class ShenandoahMarkCompact; 55 class ShenandoahMonitoringSupport; 56 class ShenandoahPacer; 57 class ShenandoahTraversalGC; 58 class ShenandoahVerifier; 59 class ShenandoahWorkGang; 60 class VMStructs; 61 62 class ShenandoahRegionIterator : public StackObj { 63 private: 64 ShenandoahHeap* _heap; 65 66 DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile size_t)); 67 volatile size_t _index; 68 DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, 0); 69 70 // No implicit copying: iterators should be passed by reference to capture the state 71 ShenandoahRegionIterator(const ShenandoahRegionIterator& that); 72 ShenandoahRegionIterator& operator=(const ShenandoahRegionIterator& o); 73 74 public: 75 ShenandoahRegionIterator(); 76 ShenandoahRegionIterator(ShenandoahHeap* heap); 77 78 // Reset iterator to default state 79 void reset(); 80 81 // Returns next region, or NULL if there are no more regions. 82 // This is multi-thread-safe. 83 inline ShenandoahHeapRegion* next(); 84 85 // This is *not* MT safe. However, in the absence of multithreaded access, it 86 // can be used to determine if there is more work to do. 87 bool has_next() const; 88 }; 89 90 class ShenandoahHeapRegionClosure : public StackObj { 91 public: 92 virtual void heap_region_do(ShenandoahHeapRegion* r) = 0; 93 virtual bool is_thread_safe() { return false; } 94 }; 95 96 #ifdef ASSERT 97 class ShenandoahAssertToSpaceClosure : public OopClosure { 98 private: 99 template <class T> 100 void do_oop_work(T* p); 101 public: 102 void do_oop(narrowOop* p); 103 void do_oop(oop* p); 104 }; 105 #endif 106 107 typedef ShenandoahLock ShenandoahHeapLock; 108 typedef ShenandoahLocker ShenandoahHeapLocker; 109 110 // Shenandoah GC is low-pause concurrent GC that uses Brooks forwarding pointers 111 // to encode forwarding data. See BrooksPointer for details on forwarding data encoding. 112 // See ShenandoahControlThread for GC cycle structure. 113 // 114 class ShenandoahHeap : public CollectedHeap { 115 friend class ShenandoahAsserts; 116 friend class VMStructs; 117 friend class ShenandoahGCSession; 118 friend class ShenandoahGCStateResetter; 119 120 // ---------- Locks that guard important data structures in Heap 121 // 122 private: 123 ShenandoahHeapLock _lock; 124 125 public: 126 ShenandoahHeapLock* lock() { 127 return &_lock; 128 } 129 130 void assert_heaplock_owned_by_current_thread() NOT_DEBUG_RETURN; 131 void assert_heaplock_not_owned_by_current_thread() NOT_DEBUG_RETURN; 132 void assert_heaplock_or_safepoint() NOT_DEBUG_RETURN; 133 134 // ---------- Initialization, termination, identification, printing routines 135 // 136 public: 137 static ShenandoahHeap* heap(); 138 static ShenandoahHeap* heap_no_check(); 139 140 const char* name() const { return "Shenandoah"; } 141 ShenandoahHeap::Name kind() const { return CollectedHeap::Shenandoah; } 142 143 ShenandoahHeap(ShenandoahCollectorPolicy* policy); 144 jint initialize(); 145 void post_initialize(); 146 void initialize_heuristics(); 147 148 void initialize_serviceability(); 149 150 void print_on(outputStream* st) const; 151 void print_extended_on(outputStream *st) const; 152 void print_tracing_info() const; 153 void print_gc_threads_on(outputStream* st) const; 154 void print_heap_regions_on(outputStream* st) const; 155 156 void stop(); 157 158 void prepare_for_verify(); 159 void verify(VerifyOption vo); 160 161 // ---------- Heap counters and metrics 162 // 163 private: 164 size_t _initial_size; 165 size_t _minimum_size; 166 DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile size_t)); 167 volatile size_t _used; 168 volatile size_t _committed; 169 volatile size_t _bytes_allocated_since_gc_start; 170 DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, 0); 171 172 public: 173 void increase_used(size_t bytes); 174 void decrease_used(size_t bytes); 175 void set_used(size_t bytes); 176 177 void increase_committed(size_t bytes); 178 void decrease_committed(size_t bytes); 179 void increase_allocated(size_t bytes); 180 181 size_t bytes_allocated_since_gc_start(); 182 void reset_bytes_allocated_since_gc_start(); 183 184 size_t min_capacity() const; 185 size_t max_capacity() const; 186 size_t initial_capacity() const; 187 size_t capacity() const; 188 size_t used() const; 189 size_t committed() const; 190 191 // ---------- Workers handling 192 // 193 private: 194 uint _max_workers; 195 ShenandoahWorkGang* _workers; 196 ShenandoahWorkGang* _safepoint_workers; 197 198 public: 199 uint max_workers(); 200 void assert_gc_workers(uint nworker) NOT_DEBUG_RETURN; 201 202 WorkGang* workers() const; 203 WorkGang* get_safepoint_workers(); 204 205 void gc_threads_do(ThreadClosure* tcl) const; 206 207 // ---------- Heap regions handling machinery 208 // 209 private: 210 MemRegion _heap_region; 211 bool _heap_region_special; 212 size_t _num_regions; 213 ShenandoahHeapRegion** _regions; 214 ShenandoahRegionIterator _update_refs_iterator; 215 216 public: 217 218 inline HeapWord* base() const { return _heap_region.start(); } 219 220 inline size_t num_regions() const { return _num_regions; } 221 inline bool is_heap_region_special() { return _heap_region_special; } 222 223 inline ShenandoahHeapRegion* const heap_region_containing(const void* addr) const; 224 inline size_t heap_region_index_containing(const void* addr) const; 225 226 inline ShenandoahHeapRegion* const get_region(size_t region_idx) const; 227 228 void heap_region_iterate(ShenandoahHeapRegionClosure* blk) const; 229 void parallel_heap_region_iterate(ShenandoahHeapRegionClosure* blk) const; 230 231 // ---------- GC state machinery 232 // 233 // GC state describes the important parts of collector state, that may be 234 // used to make barrier selection decisions in the native and generated code. 235 // Multiple bits can be set at once. 236 // 237 // Important invariant: when GC state is zero, the heap is stable, and no barriers 238 // are required. 239 // 240 public: 241 enum GCStateBitPos { 242 // Heap has forwarded objects: needs LRB barriers. 243 HAS_FORWARDED_BITPOS = 0, 244 245 // Heap is under marking: needs SATB barriers. 246 MARKING_BITPOS = 1, 247 248 // Heap is under evacuation: needs LRB barriers. (Set together with HAS_FORWARDED) 249 EVACUATION_BITPOS = 2, 250 251 // Heap is under updating: needs no additional barriers. 252 UPDATEREFS_BITPOS = 3, 253 254 // Heap is under traversal collection 255 TRAVERSAL_BITPOS = 4 256 }; 257 258 enum GCState { 259 STABLE = 0, 260 HAS_FORWARDED = 1 << HAS_FORWARDED_BITPOS, 261 MARKING = 1 << MARKING_BITPOS, 262 EVACUATION = 1 << EVACUATION_BITPOS, 263 UPDATEREFS = 1 << UPDATEREFS_BITPOS, 264 TRAVERSAL = 1 << TRAVERSAL_BITPOS 265 }; 266 267 private: 268 ShenandoahSharedBitmap _gc_state; 269 ShenandoahSharedFlag _degenerated_gc_in_progress; 270 ShenandoahSharedFlag _full_gc_in_progress; 271 ShenandoahSharedFlag _full_gc_move_in_progress; 272 ShenandoahSharedFlag _progress_last_gc; 273 274 void set_gc_state_all_threads(char state); 275 void set_gc_state_mask(uint mask, bool value); 276 277 public: 278 char gc_state() const; 279 static address gc_state_addr(); 280 281 void set_concurrent_mark_in_progress(bool in_progress); 282 void set_evacuation_in_progress(bool in_progress); 283 void set_update_refs_in_progress(bool in_progress); 284 void set_degenerated_gc_in_progress(bool in_progress); 285 void set_full_gc_in_progress(bool in_progress); 286 void set_full_gc_move_in_progress(bool in_progress); 287 void set_concurrent_traversal_in_progress(bool in_progress); 288 void set_has_forwarded_objects(bool cond); 289 290 inline bool is_stable() const; 291 inline bool is_idle() const; 292 inline bool is_concurrent_mark_in_progress() const; 293 inline bool is_update_refs_in_progress() const; 294 inline bool is_evacuation_in_progress() const; 295 inline bool is_degenerated_gc_in_progress() const; 296 inline bool is_full_gc_in_progress() const; 297 inline bool is_full_gc_move_in_progress() const; 298 inline bool is_concurrent_traversal_in_progress() const; 299 inline bool has_forwarded_objects() const; 300 inline bool is_gc_in_progress_mask(uint mask) const; 301 302 // ---------- GC cancellation and degeneration machinery 303 // 304 // Cancelled GC flag is used to notify concurrent phases that they should terminate. 305 // 306 public: 307 enum ShenandoahDegenPoint { 308 _degenerated_unset, 309 _degenerated_traversal, 310 _degenerated_outside_cycle, 311 _degenerated_mark, 312 _degenerated_evac, 313 _degenerated_updaterefs, 314 _DEGENERATED_LIMIT 315 }; 316 317 static const char* degen_point_to_string(ShenandoahDegenPoint point) { 318 switch (point) { 319 case _degenerated_unset: 320 return "<UNSET>"; 321 case _degenerated_traversal: 322 return "Traversal"; 323 case _degenerated_outside_cycle: 324 return "Outside of Cycle"; 325 case _degenerated_mark: 326 return "Mark"; 327 case _degenerated_evac: 328 return "Evacuation"; 329 case _degenerated_updaterefs: 330 return "Update Refs"; 331 default: 332 ShouldNotReachHere(); 333 return "ERROR"; 334 } 335 }; 336 337 private: 338 enum CancelState { 339 // Normal state. GC has not been cancelled and is open for cancellation. 340 // Worker threads can suspend for safepoint. 341 CANCELLABLE, 342 343 // GC has been cancelled. Worker threads can not suspend for 344 // safepoint but must finish their work as soon as possible. 345 CANCELLED, 346 347 // GC has not been cancelled and must not be cancelled. At least 348 // one worker thread checks for pending safepoint and may suspend 349 // if a safepoint is pending. 350 NOT_CANCELLED 351 }; 352 353 ShenandoahSharedEnumFlag<CancelState> _cancelled_gc; 354 bool try_cancel_gc(); 355 356 public: 357 static address cancelled_gc_addr(); 358 359 inline bool cancelled_gc() const; 360 inline bool check_cancelled_gc_and_yield(bool sts_active = true); 361 362 inline void clear_cancelled_gc(); 363 364 void cancel_gc(GCCause::Cause cause); 365 366 // ---------- GC operations entry points 367 // 368 public: 369 // Entry points to STW GC operations, these cause a related safepoint, that then 370 // call the entry method below 371 void vmop_entry_init_mark(); 372 void vmop_entry_final_mark(); 373 void vmop_entry_final_evac(); 374 void vmop_entry_init_updaterefs(); 375 void vmop_entry_final_updaterefs(); 376 void vmop_entry_init_traversal(); 377 void vmop_entry_final_traversal(); 378 void vmop_entry_full(GCCause::Cause cause); 379 void vmop_degenerated(ShenandoahDegenPoint point); 380 381 // Entry methods to normally STW GC operations. These set up logging, monitoring 382 // and workers for net VM operation 383 void entry_init_mark(); 384 void entry_final_mark(); 385 void entry_final_evac(); 386 void entry_init_updaterefs(); 387 void entry_final_updaterefs(); 388 void entry_init_traversal(); 389 void entry_final_traversal(); 390 void entry_full(GCCause::Cause cause); 391 void entry_degenerated(int point); 392 393 // Entry methods to normally concurrent GC operations. These set up logging, monitoring 394 // for concurrent operation. 395 void entry_reset(); 396 void entry_mark(); 397 void entry_preclean(); 398 void entry_roots(); 399 void entry_cleanup(); 400 void entry_evac(); 401 void entry_updaterefs(); 402 void entry_traversal(); 403 void entry_uncommit(double shrink_before); 404 405 private: 406 // Actual work for the phases 407 void op_init_mark(); 408 void op_final_mark(); 409 void op_final_evac(); 410 void op_init_updaterefs(); 411 void op_final_updaterefs(); 412 void op_init_traversal(); 413 void op_final_traversal(); 414 void op_full(GCCause::Cause cause); 415 void op_degenerated(ShenandoahDegenPoint point); 416 void op_degenerated_fail(); 417 void op_degenerated_futile(); 418 419 void op_reset(); 420 void op_mark(); 421 void op_preclean(); 422 void op_roots(); 423 void op_cleanup(); 424 void op_conc_evac(); 425 void op_stw_evac(); 426 void op_updaterefs(); 427 void op_traversal(); 428 void op_uncommit(double shrink_before); 429 430 // Messages for GC trace events, they have to be immortal for 431 // passing around the logging/tracing systems 432 const char* init_mark_event_message() const; 433 const char* final_mark_event_message() const; 434 const char* conc_mark_event_message() const; 435 const char* degen_event_message(ShenandoahDegenPoint point) const; 436 437 // ---------- GC subsystems 438 // 439 private: 440 ShenandoahControlThread* _control_thread; 441 ShenandoahCollectorPolicy* _shenandoah_policy; 442 ShenandoahMode* _gc_mode; 443 ShenandoahHeuristics* _heuristics; 444 ShenandoahFreeSet* _free_set; 445 ShenandoahConcurrentMark* _scm; 446 ShenandoahTraversalGC* _traversal_gc; 447 ShenandoahMarkCompact* _full_gc; 448 ShenandoahPacer* _pacer; 449 ShenandoahVerifier* _verifier; 450 451 ShenandoahAllocTracker* _alloc_tracker; 452 ShenandoahPhaseTimings* _phase_timings; 453 454 ShenandoahControlThread* control_thread() { return _control_thread; } 455 ShenandoahMarkCompact* full_gc() { return _full_gc; } 456 457 public: 458 ShenandoahCollectorPolicy* shenandoah_policy() const { return _shenandoah_policy; } 459 ShenandoahHeuristics* heuristics() const { return _heuristics; } 460 ShenandoahFreeSet* free_set() const { return _free_set; } 461 ShenandoahConcurrentMark* concurrent_mark() { return _scm; } 462 ShenandoahTraversalGC* traversal_gc() const { return _traversal_gc; } 463 bool is_traversal_mode() const { return _traversal_gc != NULL; } 464 ShenandoahPacer* pacer() const { return _pacer; } 465 466 ShenandoahPhaseTimings* phase_timings() const { return _phase_timings; } 467 ShenandoahAllocTracker* alloc_tracker() const { return _alloc_tracker; } 468 469 ShenandoahVerifier* verifier(); 470 471 // ---------- VM subsystem bindings 472 // 473 private: 474 ShenandoahMonitoringSupport* _monitoring_support; 475 MemoryPool* _memory_pool; 476 GCMemoryManager _stw_memory_manager; 477 GCMemoryManager _cycle_memory_manager; 478 ConcurrentGCTimer* _gc_timer; 479 SoftRefPolicy _soft_ref_policy; 480 481 // For exporting to SA 482 int _log_min_obj_alignment_in_bytes; 483 public: 484 ShenandoahMonitoringSupport* monitoring_support() { return _monitoring_support; } 485 GCMemoryManager* cycle_memory_manager() { return &_cycle_memory_manager; } 486 GCMemoryManager* stw_memory_manager() { return &_stw_memory_manager; } 487 SoftRefPolicy* soft_ref_policy() { return &_soft_ref_policy; } 488 489 GrowableArray<GCMemoryManager*> memory_managers(); 490 GrowableArray<MemoryPool*> memory_pools(); 491 MemoryUsage memory_usage(); 492 GCTracer* tracer(); 493 GCTimer* gc_timer() const; 494 495 // ---------- Reference processing 496 // 497 private: 498 AlwaysTrueClosure _subject_to_discovery; 499 ReferenceProcessor* _ref_processor; 500 ShenandoahSharedFlag _process_references; 501 502 void ref_processing_init(); 503 504 public: 505 ReferenceProcessor* ref_processor() { return _ref_processor; } 506 void set_process_references(bool pr); 507 bool process_references() const; 508 509 // ---------- Class Unloading 510 // 511 private: 512 ShenandoahSharedFlag _unload_classes; 513 514 public: 515 void set_unload_classes(bool uc); 516 bool unload_classes() const; 517 518 // Perform STW class unloading and weak root cleaning 519 void parallel_cleaning(bool full_gc); 520 521 private: 522 void stw_unload_classes(bool full_gc); 523 void stw_process_weak_roots(bool full_gc); 524 525 // ---------- Generic interface hooks 526 // Minor things that super-interface expects us to implement to play nice with 527 // the rest of runtime. Some of the things here are not required to be implemented, 528 // and can be stubbed out. 529 // 530 public: 531 AdaptiveSizePolicy* size_policy() shenandoah_not_implemented_return(NULL); 532 bool is_maximal_no_gc() const shenandoah_not_implemented_return(false); 533 534 bool is_in(const void* p) const; 535 536 MemRegion reserved_region() const { return _reserved; } 537 bool is_in_reserved(const void* addr) const { return _reserved.contains(addr); } 538 539 void collect(GCCause::Cause cause); 540 void do_full_collection(bool clear_all_soft_refs); 541 542 // Used for parsing heap during error printing 543 HeapWord* block_start(const void* addr) const; 544 bool block_is_obj(const HeapWord* addr) const; 545 bool print_location(outputStream* st, void* addr) const; 546 547 // Used for native heap walkers: heap dumpers, mostly 548 void object_iterate(ObjectClosure* cl); 549 void safe_object_iterate(ObjectClosure* cl); 550 551 // Used by RMI 552 jlong millis_since_last_gc(); 553 554 // ---------- Safepoint interface hooks 555 // 556 public: 557 void safepoint_synchronize_begin(); 558 void safepoint_synchronize_end(); 559 560 // ---------- Code roots handling hooks 561 // 562 public: 563 void register_nmethod(nmethod* nm); 564 void unregister_nmethod(nmethod* nm); 565 void flush_nmethod(nmethod* nm) {} 566 void verify_nmethod(nmethod* nm) {} 567 568 // ---------- Pinning hooks 569 // 570 public: 571 // Shenandoah supports per-object (per-region) pinning 572 bool supports_object_pinning() const { return true; } 573 574 oop pin_object(JavaThread* thread, oop obj); 575 void unpin_object(JavaThread* thread, oop obj); 576 577 // ---------- Allocation support 578 // 579 private: 580 HeapWord* allocate_memory_under_lock(ShenandoahAllocRequest& request, bool& in_new_region); 581 inline HeapWord* allocate_from_gclab(Thread* thread, size_t size); 582 HeapWord* allocate_from_gclab_slow(Thread* thread, size_t size); 583 HeapWord* allocate_new_gclab(size_t min_size, size_t word_size, size_t* actual_size); 584 void retire_and_reset_gclabs(); 585 586 public: 587 HeapWord* allocate_memory(ShenandoahAllocRequest& request); 588 HeapWord* mem_allocate(size_t size, bool* what); 589 MetaWord* satisfy_failed_metadata_allocation(ClassLoaderData* loader_data, 590 size_t size, 591 Metaspace::MetadataType mdtype); 592 593 void notify_mutator_alloc_words(size_t words, bool waste); 594 595 // Shenandoah supports TLAB allocation 596 bool supports_tlab_allocation() const { return true; } 597 598 HeapWord* allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size); 599 size_t tlab_capacity(Thread *thr) const; 600 size_t unsafe_max_tlab_alloc(Thread *thread) const; 601 size_t max_tlab_size() const; 602 size_t tlab_used(Thread* ignored) const; 603 604 void resize_tlabs(); 605 606 void ensure_parsability(bool retire_tlabs); 607 void make_parsable(bool retire_tlabs); 608 609 // ---------- Marking support 610 // 611 private: 612 ShenandoahMarkingContext* _marking_context; 613 MemRegion _bitmap_region; 614 MemRegion _aux_bitmap_region; 615 MarkBitMap _verification_bit_map; 616 MarkBitMap _aux_bit_map; 617 618 size_t _bitmap_size; 619 size_t _bitmap_regions_per_slice; 620 size_t _bitmap_bytes_per_slice; 621 622 bool _bitmap_region_special; 623 bool _aux_bitmap_region_special; 624 625 // Used for buffering per-region liveness data. 626 // Needed since ShenandoahHeapRegion uses atomics to update liveness. 627 // 628 // The array has max-workers elements, each of which is an array of 629 // jushort * max_regions. The choice of jushort is not accidental: 630 // there is a tradeoff between static/dynamic footprint that translates 631 // into cache pressure (which is already high during marking), and 632 // too many atomic updates. size_t/jint is too large, jbyte is too small. 633 jushort** _liveness_cache; 634 635 public: 636 inline ShenandoahMarkingContext* complete_marking_context() const; 637 inline ShenandoahMarkingContext* marking_context() const; 638 inline void mark_complete_marking_context(); 639 inline void mark_incomplete_marking_context(); 640 641 template<class T> 642 inline void marked_object_iterate(ShenandoahHeapRegion* region, T* cl); 643 644 template<class T> 645 inline void marked_object_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit); 646 647 template<class T> 648 inline void marked_object_oop_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit); 649 650 void reset_mark_bitmap(); 651 652 // SATB barriers hooks 653 template<bool RESOLVE> 654 inline bool requires_marking(const void* entry) const; 655 void force_satb_flush_all_threads(); 656 657 // Support for bitmap uncommits 658 bool commit_bitmap_slice(ShenandoahHeapRegion *r); 659 bool uncommit_bitmap_slice(ShenandoahHeapRegion *r); 660 bool is_bitmap_slice_committed(ShenandoahHeapRegion* r, bool skip_self = false); 661 662 // Liveness caching support 663 jushort* get_liveness_cache(uint worker_id); 664 void flush_liveness_cache(uint worker_id); 665 666 // ---------- Evacuation support 667 // 668 private: 669 ShenandoahCollectionSet* _collection_set; 670 ShenandoahEvacOOMHandler _oom_evac_handler; 671 672 void evacuate_and_update_roots(); 673 674 public: 675 static address in_cset_fast_test_addr(); 676 677 ShenandoahCollectionSet* collection_set() const { return _collection_set; } 678 679 template <class T> 680 inline bool in_collection_set(T obj) const; 681 682 // Avoid accidentally calling the method above with ShenandoahHeapRegion*, which would be *wrong*. 683 inline bool in_collection_set(ShenandoahHeapRegion* r) shenandoah_not_implemented_return(false); 684 685 // Evacuates object src. Returns the evacuated object, either evacuated 686 // by this thread, or by some other thread. 687 inline oop evacuate_object(oop src, Thread* thread); 688 689 // Call before/after evacuation. 690 void enter_evacuation(); 691 void leave_evacuation(); 692 693 // ---------- Helper functions 694 // 695 public: 696 template <class T> 697 inline oop evac_update_with_forwarded(T* p); 698 699 template <class T> 700 inline oop maybe_update_with_forwarded(T* p); 701 702 template <class T> 703 inline oop maybe_update_with_forwarded_not_null(T* p, oop obj); 704 705 template <class T> 706 inline oop update_with_forwarded_not_null(T* p, oop obj); 707 708 static inline oop cas_oop(oop n, narrowOop* addr, oop c); 709 static inline oop cas_oop(oop n, oop* addr, oop c); 710 711 void trash_humongous_region_at(ShenandoahHeapRegion *r); 712 713 void deduplicate_string(oop str); 714 715 void stop_concurrent_marking(); 716 717 private: 718 void trash_cset_regions(); 719 void update_heap_references(bool concurrent); 720 721 // ---------- Testing helpers functions 722 // 723 private: 724 ShenandoahSharedFlag _inject_alloc_failure; 725 726 void try_inject_alloc_failure(); 727 bool should_inject_alloc_failure(); 728 }; 729 730 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_HPP