1 /* 2 * Copyright (c) 2013, 2020, 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/shenandoahPadding.hpp" 35 #include "gc/shenandoah/shenandoahSharedVariables.hpp" 36 #include "gc/shenandoah/shenandoahUnload.hpp" 37 #include "services/memoryManager.hpp" 38 #include "utilities/globalDefinitions.hpp" 39 40 class ConcurrentGCTimer; 41 class ReferenceProcessor; 42 class ShenandoahCollectorPolicy; 43 class ShenandoahControlThread; 44 class ShenandoahGCSession; 45 class ShenandoahGCStateResetter; 46 class ShenandoahHeuristics; 47 class ShenandoahMarkingContext; 48 class ShenandoahMarkCompact; 49 class ShenandoahMode; 50 class ShenandoahPhaseTimings; 51 class ShenandoahHeap; 52 class ShenandoahHeapRegion; 53 class ShenandoahHeapRegionClosure; 54 class ShenandoahCollectionSet; 55 class ShenandoahFreeSet; 56 class ShenandoahConcurrentMark; 57 class ShenandoahMarkCompact; 58 class ShenandoahMonitoringSupport; 59 class ShenandoahPacer; 60 class ShenandoahVerifier; 61 class ShenandoahWorkGang; 62 class VMStructs; 63 64 // Used for buffering per-region liveness data. 65 // Needed since ShenandoahHeapRegion uses atomics to update liveness. 66 // The ShenandoahHeap array has max-workers elements, each of which is an array of 67 // uint16_t * max_regions. The choice of uint16_t is not accidental: 68 // there is a tradeoff between static/dynamic footprint that translates 69 // into cache pressure (which is already high during marking), and 70 // too many atomic updates. uint32_t is too large, uint8_t is too small. 71 typedef uint16_t ShenandoahLiveData; 72 #define SHENANDOAH_LIVEDATA_MAX ((ShenandoahLiveData)-1) 73 74 class ShenandoahRegionIterator : public StackObj { 75 private: 76 ShenandoahHeap* _heap; 77 78 shenandoah_padding(0); 79 volatile size_t _index; 80 shenandoah_padding(1); 81 82 // No implicit copying: iterators should be passed by reference to capture the state 83 NONCOPYABLE(ShenandoahRegionIterator); 84 85 public: 86 ShenandoahRegionIterator(); 87 ShenandoahRegionIterator(ShenandoahHeap* heap); 88 89 // Reset iterator to default state 90 void reset(); 91 92 // Returns next region, or NULL if there are no more regions. 93 // This is multi-thread-safe. 94 inline ShenandoahHeapRegion* next(); 95 96 // This is *not* MT safe. However, in the absence of multithreaded access, it 97 // can be used to determine if there is more work to do. 98 bool has_next() const; 99 }; 100 101 class ShenandoahHeapRegionClosure : public StackObj { 102 public: 103 virtual void heap_region_do(ShenandoahHeapRegion* r) = 0; is_thread_safe()104 virtual bool is_thread_safe() { return false; } 105 }; 106 107 #ifdef ASSERT 108 class ShenandoahAssertToSpaceClosure : public OopClosure { 109 private: 110 template <class T> 111 void do_oop_work(T* p); 112 public: 113 void do_oop(narrowOop* p); 114 void do_oop(oop* p); 115 }; 116 #endif 117 118 typedef ShenandoahLock ShenandoahHeapLock; 119 typedef ShenandoahLocker ShenandoahHeapLocker; 120 121 // Shenandoah GC is low-pause concurrent GC that uses Brooks forwarding pointers 122 // to encode forwarding data. See BrooksPointer for details on forwarding data encoding. 123 // See ShenandoahControlThread for GC cycle structure. 124 // 125 class ShenandoahHeap : public CollectedHeap { 126 friend class ShenandoahAsserts; 127 friend class VMStructs; 128 friend class ShenandoahGCSession; 129 friend class ShenandoahGCStateResetter; 130 131 // ---------- Locks that guard important data structures in Heap 132 // 133 private: 134 ShenandoahHeapLock _lock; 135 136 public: lock()137 ShenandoahHeapLock* lock() { 138 return &_lock; 139 } 140 141 // ---------- Initialization, termination, identification, printing routines 142 // 143 private: 144 static ShenandoahHeap* _heap; 145 146 public: 147 static ShenandoahHeap* heap(); 148 name() const149 const char* name() const { return "Shenandoah"; } kind() const150 ShenandoahHeap::Name kind() const { return CollectedHeap::Shenandoah; } 151 152 ShenandoahHeap(ShenandoahCollectorPolicy* policy); 153 jint initialize(); 154 void post_initialize(); 155 void initialize_heuristics(); 156 157 void initialize_serviceability(); 158 159 void print_on(outputStream* st) const; 160 void print_extended_on(outputStream *st) const; 161 void print_tracing_info() const; 162 void print_gc_threads_on(outputStream* st) const; 163 void print_heap_regions_on(outputStream* st) const; 164 165 void stop(); 166 167 void prepare_for_verify(); 168 void verify(VerifyOption vo); 169 170 // ---------- Heap counters and metrics 171 // 172 private: 173 size_t _initial_size; 174 size_t _minimum_size; 175 shenandoah_padding(0); 176 volatile size_t _used; 177 volatile size_t _committed; 178 volatile size_t _bytes_allocated_since_gc_start; 179 shenandoah_padding(1); 180 181 public: 182 void increase_used(size_t bytes); 183 void decrease_used(size_t bytes); 184 void set_used(size_t bytes); 185 186 void increase_committed(size_t bytes); 187 void decrease_committed(size_t bytes); 188 void increase_allocated(size_t bytes); 189 190 size_t bytes_allocated_since_gc_start(); 191 void reset_bytes_allocated_since_gc_start(); 192 193 size_t min_capacity() const; 194 size_t max_capacity() const; 195 size_t initial_capacity() const; 196 size_t capacity() const; 197 size_t used() const; 198 size_t committed() const; 199 200 // ---------- Workers handling 201 // 202 private: 203 uint _max_workers; 204 ShenandoahWorkGang* _workers; 205 ShenandoahWorkGang* _safepoint_workers; 206 207 public: 208 uint max_workers(); 209 void assert_gc_workers(uint nworker) NOT_DEBUG_RETURN; 210 211 WorkGang* workers() const; 212 WorkGang* get_safepoint_workers(); 213 214 void gc_threads_do(ThreadClosure* tcl) const; 215 216 // ---------- Heap regions handling machinery 217 // 218 private: 219 MemRegion _heap_region; 220 bool _heap_region_special; 221 size_t _num_regions; 222 ShenandoahHeapRegion** _regions; 223 ShenandoahRegionIterator _update_refs_iterator; 224 225 public: 226 base() const227 inline HeapWord* base() const { return _heap_region.start(); } 228 num_regions() const229 inline size_t num_regions() const { return _num_regions; } is_heap_region_special()230 inline bool is_heap_region_special() { return _heap_region_special; } 231 232 inline ShenandoahHeapRegion* const heap_region_containing(const void* addr) const; 233 inline size_t heap_region_index_containing(const void* addr) const; 234 235 inline ShenandoahHeapRegion* const get_region(size_t region_idx) const; 236 237 void heap_region_iterate(ShenandoahHeapRegionClosure* blk) const; 238 void parallel_heap_region_iterate(ShenandoahHeapRegionClosure* blk) const; 239 240 // ---------- GC state machinery 241 // 242 // GC state describes the important parts of collector state, that may be 243 // used to make barrier selection decisions in the native and generated code. 244 // Multiple bits can be set at once. 245 // 246 // Important invariant: when GC state is zero, the heap is stable, and no barriers 247 // are required. 248 // 249 public: 250 enum GCStateBitPos { 251 // Heap has forwarded objects: needs LRB barriers. 252 HAS_FORWARDED_BITPOS = 0, 253 254 // Heap is under marking: needs SATB barriers. 255 MARKING_BITPOS = 1, 256 257 // Heap is under evacuation: needs LRB barriers. (Set together with HAS_FORWARDED) 258 EVACUATION_BITPOS = 2, 259 260 // Heap is under updating: needs no additional barriers. 261 UPDATEREFS_BITPOS = 3, 262 }; 263 264 enum GCState { 265 STABLE = 0, 266 HAS_FORWARDED = 1 << HAS_FORWARDED_BITPOS, 267 MARKING = 1 << MARKING_BITPOS, 268 EVACUATION = 1 << EVACUATION_BITPOS, 269 UPDATEREFS = 1 << UPDATEREFS_BITPOS, 270 }; 271 272 private: 273 ShenandoahSharedBitmap _gc_state; 274 ShenandoahSharedFlag _degenerated_gc_in_progress; 275 ShenandoahSharedFlag _full_gc_in_progress; 276 ShenandoahSharedFlag _full_gc_move_in_progress; 277 ShenandoahSharedFlag _progress_last_gc; 278 ShenandoahSharedFlag _concurrent_root_in_progress; 279 280 void set_gc_state_all_threads(char state); 281 void set_gc_state_mask(uint mask, bool value); 282 283 public: 284 char gc_state() const; 285 static address gc_state_addr(); 286 287 void set_concurrent_mark_in_progress(bool in_progress); 288 void set_evacuation_in_progress(bool in_progress); 289 void set_update_refs_in_progress(bool in_progress); 290 void set_degenerated_gc_in_progress(bool in_progress); 291 void set_full_gc_in_progress(bool in_progress); 292 void set_full_gc_move_in_progress(bool in_progress); 293 void set_has_forwarded_objects(bool cond); 294 void set_concurrent_root_in_progress(bool cond); 295 296 inline bool is_stable() const; 297 inline bool is_idle() const; 298 inline bool is_concurrent_mark_in_progress() const; 299 inline bool is_update_refs_in_progress() const; 300 inline bool is_evacuation_in_progress() const; 301 inline bool is_degenerated_gc_in_progress() const; 302 inline bool is_full_gc_in_progress() const; 303 inline bool is_full_gc_move_in_progress() const; 304 inline bool has_forwarded_objects() const; 305 inline bool is_gc_in_progress_mask(uint mask) const; 306 inline bool is_stw_gc_in_progress() const; 307 inline bool is_concurrent_root_in_progress() const; 308 309 // ---------- GC cancellation and degeneration machinery 310 // 311 // Cancelled GC flag is used to notify concurrent phases that they should terminate. 312 // 313 public: 314 enum ShenandoahDegenPoint { 315 _degenerated_unset, 316 _degenerated_outside_cycle, 317 _degenerated_mark, 318 _degenerated_evac, 319 _degenerated_updaterefs, 320 _DEGENERATED_LIMIT 321 }; 322 degen_point_to_string(ShenandoahDegenPoint point)323 static const char* degen_point_to_string(ShenandoahDegenPoint point) { 324 switch (point) { 325 case _degenerated_unset: 326 return "<UNSET>"; 327 case _degenerated_outside_cycle: 328 return "Outside of Cycle"; 329 case _degenerated_mark: 330 return "Mark"; 331 case _degenerated_evac: 332 return "Evacuation"; 333 case _degenerated_updaterefs: 334 return "Update Refs"; 335 default: 336 ShouldNotReachHere(); 337 return "ERROR"; 338 } 339 }; 340 341 private: 342 enum CancelState { 343 // Normal state. GC has not been cancelled and is open for cancellation. 344 // Worker threads can suspend for safepoint. 345 CANCELLABLE, 346 347 // GC has been cancelled. Worker threads can not suspend for 348 // safepoint but must finish their work as soon as possible. 349 CANCELLED, 350 351 // GC has not been cancelled and must not be cancelled. At least 352 // one worker thread checks for pending safepoint and may suspend 353 // if a safepoint is pending. 354 NOT_CANCELLED 355 }; 356 357 ShenandoahSharedEnumFlag<CancelState> _cancelled_gc; 358 bool try_cancel_gc(); 359 360 public: 361 static address cancelled_gc_addr(); 362 363 inline bool cancelled_gc() const; 364 inline bool check_cancelled_gc_and_yield(bool sts_active = true); 365 366 inline void clear_cancelled_gc(); 367 368 void cancel_gc(GCCause::Cause cause); 369 370 // ---------- GC operations entry points 371 // 372 public: 373 // Entry points to STW GC operations, these cause a related safepoint, that then 374 // call the entry method below 375 void vmop_entry_init_mark(); 376 void vmop_entry_final_mark(); 377 void vmop_entry_init_updaterefs(); 378 void vmop_entry_final_updaterefs(); 379 void vmop_entry_full(GCCause::Cause cause); 380 void vmop_degenerated(ShenandoahDegenPoint point); 381 382 // Entry methods to normally STW GC operations. These set up logging, monitoring 383 // and workers for net VM operation 384 void entry_init_mark(); 385 void entry_final_mark(); 386 void entry_init_updaterefs(); 387 void entry_final_updaterefs(); 388 void entry_full(GCCause::Cause cause); 389 void entry_degenerated(int point); 390 391 // Entry methods to normally concurrent GC operations. These set up logging, monitoring 392 // for concurrent operation. 393 void entry_reset(); 394 void entry_mark(); 395 void entry_preclean(); 396 void entry_roots(); 397 void entry_cleanup_early(); 398 void entry_evac(); 399 void entry_updaterefs(); 400 void entry_cleanup_complete(); 401 void entry_uncommit(double shrink_before); 402 403 private: 404 // Actual work for the phases 405 void op_init_mark(); 406 void op_final_mark(); 407 void op_init_updaterefs(); 408 void op_final_updaterefs(); 409 void op_full(GCCause::Cause cause); 410 void op_degenerated(ShenandoahDegenPoint point); 411 void op_degenerated_fail(); 412 void op_degenerated_futile(); 413 414 void op_reset(); 415 void op_mark(); 416 void op_preclean(); 417 void op_roots(); 418 void op_cleanup_early(); 419 void op_conc_evac(); 420 void op_stw_evac(); 421 void op_updaterefs(); 422 void op_cleanup_complete(); 423 void op_uncommit(double shrink_before); 424 425 // Messages for GC trace events, they have to be immortal for 426 // passing around the logging/tracing systems 427 const char* init_mark_event_message() const; 428 const char* final_mark_event_message() const; 429 const char* conc_mark_event_message() const; 430 const char* degen_event_message(ShenandoahDegenPoint point) const; 431 432 // ---------- GC subsystems 433 // 434 private: 435 ShenandoahControlThread* _control_thread; 436 ShenandoahCollectorPolicy* _shenandoah_policy; 437 ShenandoahMode* _gc_mode; 438 ShenandoahHeuristics* _heuristics; 439 ShenandoahFreeSet* _free_set; 440 ShenandoahConcurrentMark* _scm; 441 ShenandoahMarkCompact* _full_gc; 442 ShenandoahPacer* _pacer; 443 ShenandoahVerifier* _verifier; 444 445 ShenandoahPhaseTimings* _phase_timings; 446 control_thread()447 ShenandoahControlThread* control_thread() { return _control_thread; } full_gc()448 ShenandoahMarkCompact* full_gc() { return _full_gc; } 449 450 public: shenandoah_policy() const451 ShenandoahCollectorPolicy* shenandoah_policy() const { return _shenandoah_policy; } heuristics() const452 ShenandoahHeuristics* heuristics() const { return _heuristics; } free_set() const453 ShenandoahFreeSet* free_set() const { return _free_set; } concurrent_mark()454 ShenandoahConcurrentMark* concurrent_mark() { return _scm; } pacer() const455 ShenandoahPacer* pacer() const { return _pacer; } 456 phase_timings() const457 ShenandoahPhaseTimings* phase_timings() const { return _phase_timings; } 458 459 ShenandoahVerifier* verifier(); 460 461 // ---------- VM subsystem bindings 462 // 463 private: 464 ShenandoahMonitoringSupport* _monitoring_support; 465 MemoryPool* _memory_pool; 466 GCMemoryManager _stw_memory_manager; 467 GCMemoryManager _cycle_memory_manager; 468 ConcurrentGCTimer* _gc_timer; 469 SoftRefPolicy _soft_ref_policy; 470 471 // For exporting to SA 472 int _log_min_obj_alignment_in_bytes; 473 public: monitoring_support()474 ShenandoahMonitoringSupport* monitoring_support() { return _monitoring_support; } cycle_memory_manager()475 GCMemoryManager* cycle_memory_manager() { return &_cycle_memory_manager; } stw_memory_manager()476 GCMemoryManager* stw_memory_manager() { return &_stw_memory_manager; } soft_ref_policy()477 SoftRefPolicy* soft_ref_policy() { return &_soft_ref_policy; } 478 479 GrowableArray<GCMemoryManager*> memory_managers(); 480 GrowableArray<MemoryPool*> memory_pools(); 481 MemoryUsage memory_usage(); 482 GCTracer* tracer(); 483 ConcurrentGCTimer* gc_timer() const; 484 485 // ---------- Reference processing 486 // 487 private: 488 AlwaysTrueClosure _subject_to_discovery; 489 ReferenceProcessor* _ref_processor; 490 ShenandoahSharedFlag _process_references; 491 492 void ref_processing_init(); 493 494 public: ref_processor()495 ReferenceProcessor* ref_processor() { return _ref_processor; } 496 void set_process_references(bool pr); 497 bool process_references() const; 498 499 // ---------- Class Unloading 500 // 501 private: 502 ShenandoahSharedFlag _unload_classes; 503 ShenandoahUnload _unloader; 504 505 public: 506 void set_unload_classes(bool uc); 507 bool unload_classes() const; 508 509 // Perform STW class unloading and weak root cleaning 510 void parallel_cleaning(bool full_gc); 511 512 private: 513 void stw_unload_classes(bool full_gc); 514 void stw_process_weak_roots(bool full_gc); 515 516 // Prepare concurrent root processing 517 void prepare_concurrent_roots(); 518 // Prepare and finish concurrent unloading 519 void prepare_concurrent_unloading(); 520 void finish_concurrent_unloading(); 521 522 // ---------- Generic interface hooks 523 // Minor things that super-interface expects us to implement to play nice with 524 // the rest of runtime. Some of the things here are not required to be implemented, 525 // and can be stubbed out. 526 // 527 public: 528 AdaptiveSizePolicy* size_policy() shenandoah_not_implemented_return(NULL); 529 bool is_maximal_no_gc() const shenandoah_not_implemented_return(false); 530 531 bool is_in(const void* p) const; 532 reserved_region() const533 MemRegion reserved_region() const { return _reserved; } is_in_reserved(const void * addr) const534 bool is_in_reserved(const void* addr) const { return _reserved.contains(addr); } 535 536 void collect(GCCause::Cause cause); 537 void do_full_collection(bool clear_all_soft_refs); 538 539 // Used for parsing heap during error printing 540 HeapWord* block_start(const void* addr) const; 541 bool block_is_obj(const HeapWord* addr) const; 542 bool print_location(outputStream* st, void* addr) const; 543 544 // Used for native heap walkers: heap dumpers, mostly 545 void object_iterate(ObjectClosure* cl); 546 547 // Keep alive an object that was loaded with AS_NO_KEEPALIVE. 548 void keep_alive(oop obj); 549 550 // Used by RMI 551 jlong millis_since_last_gc(); 552 553 // ---------- Safepoint interface hooks 554 // 555 public: 556 void safepoint_synchronize_begin(); 557 void safepoint_synchronize_end(); 558 559 // ---------- Code roots handling hooks 560 // 561 public: 562 void register_nmethod(nmethod* nm); 563 void unregister_nmethod(nmethod* nm); 564 void flush_nmethod(nmethod* nm); verify_nmethod(nmethod * nm)565 void verify_nmethod(nmethod* nm) {} 566 567 // ---------- Pinning hooks 568 // 569 public: 570 // Shenandoah supports per-object (per-region) pinning supports_object_pinning() const571 bool supports_object_pinning() const { return true; } 572 573 oop pin_object(JavaThread* thread, oop obj); 574 void unpin_object(JavaThread* thread, oop obj); 575 576 void sync_pinned_region_status(); 577 void assert_pinned_region_status() NOT_DEBUG_RETURN; 578 579 // ---------- Allocation support 580 // 581 private: 582 HeapWord* allocate_memory_under_lock(ShenandoahAllocRequest& request, bool& in_new_region); 583 inline HeapWord* allocate_from_gclab(Thread* thread, size_t size); 584 HeapWord* allocate_from_gclab_slow(Thread* thread, size_t size); 585 HeapWord* allocate_new_gclab(size_t min_size, size_t word_size, size_t* actual_size); 586 void retire_and_reset_gclabs(); 587 588 public: 589 HeapWord* allocate_memory(ShenandoahAllocRequest& request); 590 HeapWord* mem_allocate(size_t size, bool* what); 591 MetaWord* satisfy_failed_metadata_allocation(ClassLoaderData* loader_data, 592 size_t size, 593 Metaspace::MetadataType mdtype); 594 595 void notify_mutator_alloc_words(size_t words, bool waste); 596 597 // Shenandoah supports TLAB allocation supports_tlab_allocation() const598 bool supports_tlab_allocation() const { return true; } 599 600 HeapWord* allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size); 601 size_t tlab_capacity(Thread *thr) const; 602 size_t unsafe_max_tlab_alloc(Thread *thread) const; 603 size_t max_tlab_size() const; 604 size_t tlab_used(Thread* ignored) const; 605 606 void resize_tlabs(); 607 608 void ensure_parsability(bool retire_tlabs); 609 void make_parsable(bool retire_tlabs); 610 611 // ---------- Marking support 612 // 613 private: 614 ShenandoahMarkingContext* _marking_context; 615 MemRegion _bitmap_region; 616 MemRegion _aux_bitmap_region; 617 MarkBitMap _verification_bit_map; 618 MarkBitMap _aux_bit_map; 619 620 size_t _bitmap_size; 621 size_t _bitmap_regions_per_slice; 622 size_t _bitmap_bytes_per_slice; 623 624 size_t _pretouch_heap_page_size; 625 size_t _pretouch_bitmap_page_size; 626 627 bool _bitmap_region_special; 628 bool _aux_bitmap_region_special; 629 630 ShenandoahLiveData** _liveness_cache; 631 632 public: 633 inline ShenandoahMarkingContext* complete_marking_context() const; 634 inline ShenandoahMarkingContext* marking_context() const; 635 inline void mark_complete_marking_context(); 636 inline void mark_incomplete_marking_context(); 637 638 template<class T> 639 inline void marked_object_iterate(ShenandoahHeapRegion* region, T* cl); 640 641 template<class T> 642 inline void marked_object_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit); 643 644 template<class T> 645 inline void marked_object_oop_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit); 646 647 void reset_mark_bitmap(); 648 649 // SATB barriers hooks 650 template<bool RESOLVE> 651 inline bool requires_marking(const void* entry) const; 652 void force_satb_flush_all_threads(); 653 654 // Support for bitmap uncommits 655 bool commit_bitmap_slice(ShenandoahHeapRegion *r); 656 bool uncommit_bitmap_slice(ShenandoahHeapRegion *r); 657 bool is_bitmap_slice_committed(ShenandoahHeapRegion* r, bool skip_self = false); 658 659 // Liveness caching support 660 ShenandoahLiveData* get_liveness_cache(uint worker_id); 661 void flush_liveness_cache(uint worker_id); 662 pretouch_heap_page_size()663 size_t pretouch_heap_page_size() { return _pretouch_heap_page_size; } 664 665 // ---------- Evacuation support 666 // 667 private: 668 ShenandoahCollectionSet* _collection_set; 669 ShenandoahEvacOOMHandler _oom_evac_handler; 670 671 void evacuate_and_update_roots(); 672 673 public: 674 static address in_cset_fast_test_addr(); 675 collection_set() const676 ShenandoahCollectionSet* collection_set() const { return _collection_set; } 677 678 // Checks if object is in the collection set. 679 inline bool in_collection_set(oop obj) const; 680 681 // Checks if location is in the collection set. Can be interior pointer, not the oop itself. 682 inline bool in_collection_set_loc(void* loc) const; 683 684 // Evacuates object src. Returns the evacuated object, either evacuated 685 // by this thread, or by some other thread. 686 inline oop evacuate_object(oop src, Thread* thread); 687 688 // Call before/after evacuation. 689 void enter_evacuation(); 690 void leave_evacuation(); 691 692 // ---------- Helper functions 693 // 694 public: 695 template <class T> 696 inline oop evac_update_with_forwarded(T* p); 697 698 template <class T> 699 inline oop maybe_update_with_forwarded(T* p); 700 701 template <class T> 702 inline oop maybe_update_with_forwarded_not_null(T* p, oop obj); 703 704 template <class T> 705 inline oop update_with_forwarded_not_null(T* p, oop obj); 706 707 static inline oop cas_oop(oop n, narrowOop* addr, oop c); 708 static inline oop cas_oop(oop n, oop* addr, oop c); 709 static inline oop cas_oop(oop n, narrowOop* addr, narrowOop c); 710 711 void trash_humongous_region_at(ShenandoahHeapRegion *r); 712 713 void deduplicate_string(oop str); 714 715 private: 716 void trash_cset_regions(); 717 void update_heap_references(bool concurrent); 718 719 // ---------- Testing helpers functions 720 // 721 private: 722 ShenandoahSharedFlag _inject_alloc_failure; 723 724 void try_inject_alloc_failure(); 725 bool should_inject_alloc_failure(); 726 }; 727 728 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_HPP 729