1 /*
2 * Copyright (c) 2013, 2020, Red Hat, Inc. 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 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_HPP
26 #define SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_HPP
27
28 #include "gc/shared/markBitMap.hpp"
29 #include "gc/shared/softRefPolicy.hpp"
30 #include "gc/shared/collectedHeap.hpp"
31 #include "gc/shenandoah/shenandoahAsserts.hpp"
32 #include "gc/shenandoah/shenandoahAllocRequest.hpp"
33 #include "gc/shenandoah/shenandoahLock.hpp"
34 #include "gc/shenandoah/shenandoahEvacOOMHandler.hpp"
35 #include "gc/shenandoah/shenandoahPadding.hpp"
36 #include "gc/shenandoah/shenandoahSharedVariables.hpp"
37 #include "gc/shenandoah/shenandoahUnload.hpp"
38 #include "services/memoryManager.hpp"
39 #include "utilities/globalDefinitions.hpp"
40
41 class ConcurrentGCTimer;
42 class ReferenceProcessor;
43 class ShenandoahCollectorPolicy;
44 class ShenandoahControlThread;
45 class ShenandoahGCSession;
46 class ShenandoahGCStateResetter;
47 class ShenandoahHeuristics;
48 class ShenandoahMarkingContext;
49 class ShenandoahMarkCompact;
50 class ShenandoahMode;
51 class ShenandoahPhaseTimings;
52 class ShenandoahHeap;
53 class ShenandoahHeapRegion;
54 class ShenandoahHeapRegionClosure;
55 class ShenandoahCollectionSet;
56 class ShenandoahFreeSet;
57 class ShenandoahConcurrentMark;
58 class ShenandoahMarkCompact;
59 class ShenandoahMonitoringSupport;
60 class ShenandoahPacer;
61 class ShenandoahVerifier;
62 class ShenandoahWorkGang;
63 class VMStructs;
64
65 // Used for buffering per-region liveness data.
66 // Needed since ShenandoahHeapRegion uses atomics to update liveness.
67 // The ShenandoahHeap array has max-workers elements, each of which is an array of
68 // uint16_t * max_regions. The choice of uint16_t is not accidental:
69 // there is a tradeoff between static/dynamic footprint that translates
70 // into cache pressure (which is already high during marking), and
71 // too many atomic updates. uint32_t is too large, uint8_t is too small.
72 typedef uint16_t ShenandoahLiveData;
73 #define SHENANDOAH_LIVEDATA_MAX ((ShenandoahLiveData)-1)
74
75 class ShenandoahRegionIterator : public StackObj {
76 private:
77 ShenandoahHeap* _heap;
78
79 shenandoah_padding(0);
80 volatile size_t _index;
81 shenandoah_padding(1);
82
83 // No implicit copying: iterators should be passed by reference to capture the state
84 NONCOPYABLE(ShenandoahRegionIterator);
85
86 public:
87 ShenandoahRegionIterator();
88 ShenandoahRegionIterator(ShenandoahHeap* heap);
89
90 // Reset iterator to default state
91 void reset();
92
93 // Returns next region, or NULL if there are no more regions.
94 // This is multi-thread-safe.
95 inline ShenandoahHeapRegion* next();
96
97 // This is *not* MT safe. However, in the absence of multithreaded access, it
98 // can be used to determine if there is more work to do.
99 bool has_next() const;
100 };
101
102 class ShenandoahHeapRegionClosure : public StackObj {
103 public:
104 virtual void heap_region_do(ShenandoahHeapRegion* r) = 0;
105 virtual bool is_thread_safe() { return false; }
106 };
107
108 typedef ShenandoahLock ShenandoahHeapLock;
109 typedef ShenandoahLocker ShenandoahHeapLocker;
110
111 // Shenandoah GC is low-pause concurrent GC that uses Brooks forwarding pointers
112 // to encode forwarding data. See BrooksPointer for details on forwarding data encoding.
113 // See ShenandoahControlThread for GC cycle structure.
114 //
115 class ShenandoahHeap : public CollectedHeap {
116 friend class ShenandoahAsserts;
117 friend class VMStructs;
118 friend class ShenandoahGCSession;
119 friend class ShenandoahGCStateResetter;
120
121 // ---------- Locks that guard important data structures in Heap
122 //
123 private:
124 ShenandoahHeapLock _lock;
125
126 public:
127 ShenandoahHeapLock* lock() {
128 return &_lock;
129 }
130
131 // ---------- Initialization, termination, identification, printing routines
132 //
133 public:
134 static ShenandoahHeap* heap();
135
136 const char* name() const { return "Shenandoah"; }
137 ShenandoahHeap::Name kind() const { return CollectedHeap::Shenandoah; }
138
139 ShenandoahHeap(ShenandoahCollectorPolicy* policy);
140 jint initialize();
141 void post_initialize();
142 void initialize_heuristics();
143
144 void initialize_serviceability();
145
146 void print_on(outputStream* st) const;
147 void print_extended_on(outputStream *st) const;
148 void print_tracing_info() const;
149 void print_heap_regions_on(outputStream* st) const;
150
151 void stop();
152
153 void prepare_for_verify();
154 void verify(VerifyOption vo);
155
156 // ---------- Heap counters and metrics
157 //
158 private:
159 size_t _initial_size;
160 size_t _minimum_size;
161 shenandoah_padding(0);
162 volatile size_t _used;
163 volatile size_t _committed;
164 volatile size_t _bytes_allocated_since_gc_start;
165 shenandoah_padding(1);
166
167 public:
168 void increase_used(size_t bytes);
169 void decrease_used(size_t bytes);
170 void set_used(size_t bytes);
171
172 void increase_committed(size_t bytes);
173 void decrease_committed(size_t bytes);
174 void increase_allocated(size_t bytes);
175
176 size_t bytes_allocated_since_gc_start();
177 void reset_bytes_allocated_since_gc_start();
178
179 size_t min_capacity() const;
180 size_t max_capacity() const;
181 size_t initial_capacity() const;
182 size_t capacity() const;
183 size_t used() const;
184 size_t committed() const;
185
186 // ---------- Workers handling
187 //
188 private:
189 uint _max_workers;
190 ShenandoahWorkGang* _workers;
191 ShenandoahWorkGang* _safepoint_workers;
192
193 public:
194 uint max_workers();
195 void assert_gc_workers(uint nworker) NOT_DEBUG_RETURN;
196
197 WorkGang* workers() const;
198 WorkGang* get_safepoint_workers();
199
200 void gc_threads_do(ThreadClosure* tcl) const;
201
202 // ---------- Heap regions handling machinery
203 //
204 private:
205 MemRegion _heap_region;
206 bool _heap_region_special;
207 size_t _num_regions;
208 ShenandoahHeapRegion** _regions;
209 ShenandoahRegionIterator _update_refs_iterator;
210
211 public:
212
213 inline HeapWord* base() const { return _heap_region.start(); }
214
215 inline size_t num_regions() const { return _num_regions; }
216 inline bool is_heap_region_special() { return _heap_region_special; }
217
218 inline ShenandoahHeapRegion* const heap_region_containing(const void* addr) const;
219 inline size_t heap_region_index_containing(const void* addr) const;
220
221 inline ShenandoahHeapRegion* const get_region(size_t region_idx) const;
222
223 void heap_region_iterate(ShenandoahHeapRegionClosure* blk) const;
224 void parallel_heap_region_iterate(ShenandoahHeapRegionClosure* blk) const;
225
226 // ---------- GC state machinery
227 //
228 // GC state describes the important parts of collector state, that may be
229 // used to make barrier selection decisions in the native and generated code.
230 // Multiple bits can be set at once.
231 //
232 // Important invariant: when GC state is zero, the heap is stable, and no barriers
233 // are required.
234 //
235 public:
236 enum GCStateBitPos {
237 // Heap has forwarded objects: needs LRB barriers.
238 HAS_FORWARDED_BITPOS = 0,
239
240 // Heap is under marking: needs SATB barriers.
241 MARKING_BITPOS = 1,
242
243 // Heap is under evacuation: needs LRB barriers. (Set together with HAS_FORWARDED)
244 EVACUATION_BITPOS = 2,
245
246 // Heap is under updating: needs no additional barriers.
247 UPDATEREFS_BITPOS = 3,
248 };
249
250 enum GCState {
251 STABLE = 0,
252 HAS_FORWARDED = 1 << HAS_FORWARDED_BITPOS,
253 MARKING = 1 << MARKING_BITPOS,
254 EVACUATION = 1 << EVACUATION_BITPOS,
255 UPDATEREFS = 1 << UPDATEREFS_BITPOS,
256 };
257
258 private:
259 ShenandoahSharedBitmap _gc_state;
260 ShenandoahSharedFlag _degenerated_gc_in_progress;
261 ShenandoahSharedFlag _full_gc_in_progress;
262 ShenandoahSharedFlag _full_gc_move_in_progress;
263 ShenandoahSharedFlag _progress_last_gc;
264 ShenandoahSharedFlag _concurrent_strong_root_in_progress;
265 ShenandoahSharedFlag _concurrent_weak_root_in_progress;
266
267 void set_gc_state_all_threads(char state);
268 void set_gc_state_mask(uint mask, bool value);
269
270 public:
271 char gc_state() const;
272 static address gc_state_addr();
273
274 void set_concurrent_mark_in_progress(bool in_progress);
275 void set_evacuation_in_progress(bool in_progress);
276 void set_update_refs_in_progress(bool in_progress);
277 void set_degenerated_gc_in_progress(bool in_progress);
278 void set_full_gc_in_progress(bool in_progress);
279 void set_full_gc_move_in_progress(bool in_progress);
280 void set_has_forwarded_objects(bool cond);
281 void set_concurrent_strong_root_in_progress(bool cond);
282 void set_concurrent_weak_root_in_progress(bool cond);
283
284 inline bool is_stable() const;
285 inline bool is_idle() const;
286 inline bool is_concurrent_mark_in_progress() const;
287 inline bool is_update_refs_in_progress() const;
288 inline bool is_evacuation_in_progress() const;
289 inline bool is_degenerated_gc_in_progress() const;
290 inline bool is_full_gc_in_progress() const;
291 inline bool is_full_gc_move_in_progress() const;
292 inline bool has_forwarded_objects() const;
293 inline bool is_gc_in_progress_mask(uint mask) const;
294 inline bool is_stw_gc_in_progress() const;
295 inline bool is_concurrent_strong_root_in_progress() const;
296 inline bool is_concurrent_weak_root_in_progress() const;
297
298 // ---------- GC cancellation and degeneration machinery
299 //
300 // Cancelled GC flag is used to notify concurrent phases that they should terminate.
301 //
302 public:
303 enum ShenandoahDegenPoint {
304 _degenerated_unset,
305 _degenerated_outside_cycle,
306 _degenerated_mark,
307 _degenerated_evac,
308 _degenerated_updaterefs,
309 _DEGENERATED_LIMIT
310 };
311
312 static const char* degen_point_to_string(ShenandoahDegenPoint point) {
313 switch (point) {
314 case _degenerated_unset:
315 return "<UNSET>";
316 case _degenerated_outside_cycle:
317 return "Outside of Cycle";
318 case _degenerated_mark:
319 return "Mark";
320 case _degenerated_evac:
321 return "Evacuation";
322 case _degenerated_updaterefs:
323 return "Update Refs";
324 default:
325 ShouldNotReachHere();
326 return "ERROR";
327 }
328 };
329
330 private:
331 enum CancelState {
332 // Normal state. GC has not been cancelled and is open for cancellation.
333 // Worker threads can suspend for safepoint.
334 CANCELLABLE,
335
336 // GC has been cancelled. Worker threads can not suspend for
337 // safepoint but must finish their work as soon as possible.
338 CANCELLED,
339
340 // GC has not been cancelled and must not be cancelled. At least
341 // one worker thread checks for pending safepoint and may suspend
342 // if a safepoint is pending.
343 NOT_CANCELLED
344 };
345
346 ShenandoahSharedEnumFlag<CancelState> _cancelled_gc;
347 bool try_cancel_gc();
348
349 public:
350 static address cancelled_gc_addr();
351
352 inline bool cancelled_gc() const;
353 inline bool check_cancelled_gc_and_yield(bool sts_active = true);
354
355 inline void clear_cancelled_gc();
356
357 void cancel_gc(GCCause::Cause cause);
358
359 // ---------- GC operations entry points
360 //
361 public:
362 // Entry points to STW GC operations, these cause a related safepoint, that then
363 // call the entry method below
364 void vmop_entry_init_mark();
365 void vmop_entry_final_mark();
366 void vmop_entry_init_updaterefs();
367 void vmop_entry_final_updaterefs();
368 void vmop_entry_full(GCCause::Cause cause);
369 void vmop_degenerated(ShenandoahDegenPoint point);
370
371 // Entry methods to normally STW GC operations. These set up logging, monitoring
372 // and workers for net VM operation
373 void entry_init_mark();
374 void entry_final_mark();
375 void entry_init_updaterefs();
376 void entry_final_updaterefs();
377 void entry_full(GCCause::Cause cause);
378 void entry_degenerated(int point);
379
380 // Entry methods to normally concurrent GC operations. These set up logging, monitoring
381 // for concurrent operation.
382 void entry_reset();
383 void entry_mark();
384 void entry_preclean();
385 void entry_weak_roots();
386 void entry_class_unloading();
387 void entry_strong_roots();
388 void entry_cleanup_early();
389 void entry_evac();
390 void entry_updaterefs();
391 void entry_cleanup_complete();
392 void entry_uncommit(double shrink_before);
393
394 private:
395 // Actual work for the phases
396 void op_init_mark();
397 void op_final_mark();
398 void op_init_updaterefs();
399 void op_final_updaterefs();
400 void op_full(GCCause::Cause cause);
401 void op_degenerated(ShenandoahDegenPoint point);
402 void op_degenerated_fail();
403 void op_degenerated_futile();
404
405 void op_reset();
406 void op_mark();
407 void op_preclean();
408 void op_weak_roots();
409 void op_class_unloading();
410 void op_strong_roots();
411 void op_cleanup_early();
412 void op_conc_evac();
413 void op_stw_evac();
414 void op_updaterefs();
415 void op_cleanup_complete();
416 void op_uncommit(double shrink_before);
417
418 // Messages for GC trace events, they have to be immortal for
419 // passing around the logging/tracing systems
420 const char* init_mark_event_message() const;
421 const char* final_mark_event_message() const;
422 const char* conc_mark_event_message() const;
423 const char* degen_event_message(ShenandoahDegenPoint point) const;
424
425 // ---------- GC subsystems
426 //
427 private:
428 ShenandoahControlThread* _control_thread;
429 ShenandoahCollectorPolicy* _shenandoah_policy;
430 ShenandoahMode* _gc_mode;
431 ShenandoahHeuristics* _heuristics;
432 ShenandoahFreeSet* _free_set;
433 ShenandoahConcurrentMark* _scm;
434 ShenandoahMarkCompact* _full_gc;
435 ShenandoahPacer* _pacer;
436 ShenandoahVerifier* _verifier;
437
438 ShenandoahPhaseTimings* _phase_timings;
439
440 ShenandoahControlThread* control_thread() { return _control_thread; }
441 ShenandoahMarkCompact* full_gc() { return _full_gc; }
442
443 public:
444 ShenandoahCollectorPolicy* shenandoah_policy() const { return _shenandoah_policy; }
445 ShenandoahMode* mode() const { return _gc_mode; }
446 ShenandoahHeuristics* heuristics() const { return _heuristics; }
447 ShenandoahFreeSet* free_set() const { return _free_set; }
448 ShenandoahConcurrentMark* concurrent_mark() { return _scm; }
449 ShenandoahPacer* pacer() const { return _pacer; }
450
451 ShenandoahPhaseTimings* phase_timings() const { return _phase_timings; }
452
453 ShenandoahVerifier* verifier();
454
455 // ---------- VM subsystem bindings
456 //
457 private:
458 ShenandoahMonitoringSupport* _monitoring_support;
459 MemoryPool* _memory_pool;
460 GCMemoryManager _stw_memory_manager;
461 GCMemoryManager _cycle_memory_manager;
462 ConcurrentGCTimer* _gc_timer;
463 SoftRefPolicy _soft_ref_policy;
464
465 // For exporting to SA
466 int _log_min_obj_alignment_in_bytes;
467 public:
468 ShenandoahMonitoringSupport* monitoring_support() { return _monitoring_support; }
469 GCMemoryManager* cycle_memory_manager() { return &_cycle_memory_manager; }
470 GCMemoryManager* stw_memory_manager() { return &_stw_memory_manager; }
471 SoftRefPolicy* soft_ref_policy() { return &_soft_ref_policy; }
472
473 GrowableArray<GCMemoryManager*> memory_managers();
474 GrowableArray<MemoryPool*> memory_pools();
475 MemoryUsage memory_usage();
476 GCTracer* tracer();
477 ConcurrentGCTimer* gc_timer() const;
478
479 // ---------- Reference processing
480 //
481 private:
482 AlwaysTrueClosure _subject_to_discovery;
483 ReferenceProcessor* _ref_processor;
484 ShenandoahSharedFlag _process_references;
485 bool _ref_proc_mt_discovery;
486 bool _ref_proc_mt_processing;
487
488 void ref_processing_init();
489
490 public:
491 ReferenceProcessor* ref_processor() { return _ref_processor; }
492 bool ref_processor_mt_discovery() { return _ref_proc_mt_discovery; }
493 bool ref_processor_mt_processing() { return _ref_proc_mt_processing; }
494 void set_process_references(bool pr);
495 bool process_references() const;
496
497 // ---------- Class Unloading
498 //
499 private:
500 ShenandoahSharedFlag _unload_classes;
501 ShenandoahUnload _unloader;
502
503 public:
504 void set_unload_classes(bool uc);
505 bool unload_classes() const;
506
507 // Perform STW class unloading and weak root cleaning
508 void parallel_cleaning(bool full_gc);
509
510 private:
511 void stw_unload_classes(bool full_gc);
512 void stw_process_weak_roots(bool full_gc);
513
514 // Prepare concurrent root processing
515 void prepare_concurrent_roots();
516 // Prepare and finish concurrent unloading
517 void prepare_concurrent_unloading();
518 void finish_concurrent_unloading();
519
520 // ---------- Generic interface hooks
521 // Minor things that super-interface expects us to implement to play nice with
522 // the rest of runtime. Some of the things here are not required to be implemented,
523 // and can be stubbed out.
524 //
525 public:
526 AdaptiveSizePolicy* size_policy() shenandoah_not_implemented_return(NULL);
527 bool is_maximal_no_gc() const shenandoah_not_implemented_return(false);
528
529 bool is_in(const void* p) const;
530
531 MemRegion reserved_region() const { return _reserved; }
532 bool is_in_reserved(const void* addr) const { return _reserved.contains(addr); }
533
534 void collect(GCCause::Cause cause);
535 void do_full_collection(bool clear_all_soft_refs);
536
537 // Used for parsing heap during error printing
538 HeapWord* block_start(const void* addr) const;
539 bool block_is_obj(const HeapWord* addr) const;
540 bool print_location(outputStream* st, void* addr) const;
541
542 // Used for native heap walkers: heap dumpers, mostly
543 void object_iterate(ObjectClosure* cl);
544
545 // Keep alive an object that was loaded with AS_NO_KEEPALIVE.
546 void keep_alive(oop obj);
547
548 // ---------- Safepoint interface hooks
549 //
550 public:
551 void safepoint_synchronize_begin();
552 void safepoint_synchronize_end();
553
554 // ---------- Code roots handling hooks
555 //
556 public:
557 void register_nmethod(nmethod* nm);
558 void unregister_nmethod(nmethod* nm);
559 void flush_nmethod(nmethod* nm);
560 void verify_nmethod(nmethod* nm) {}
561
562 // ---------- Pinning hooks
563 //
564 public:
565 // Shenandoah supports per-object (per-region) pinning
566 bool supports_object_pinning() const { return true; }
567
568 oop pin_object(JavaThread* thread, oop obj);
569 void unpin_object(JavaThread* thread, oop obj);
570
571 void sync_pinned_region_status();
572 void assert_pinned_region_status() NOT_DEBUG_RETURN;
573
574 // ---------- Allocation support
575 //
576 private:
577 HeapWord* allocate_memory_under_lock(ShenandoahAllocRequest& request, bool& in_new_region);
578 inline HeapWord* allocate_from_gclab(Thread* thread, size_t size);
579 HeapWord* allocate_from_gclab_slow(Thread* thread, size_t size);
580 HeapWord* allocate_new_gclab(size_t min_size, size_t word_size, size_t* actual_size);
581
582 public:
583 HeapWord* allocate_memory(ShenandoahAllocRequest& request);
584 HeapWord* mem_allocate(size_t size, bool* what);
585 MetaWord* satisfy_failed_metadata_allocation(ClassLoaderData* loader_data,
586 size_t size,
587 Metaspace::MetadataType mdtype);
588
589 void notify_mutator_alloc_words(size_t words, bool waste);
590
591 // Shenandoah supports TLAB allocation
592 bool supports_tlab_allocation() const { return true; }
593
594 HeapWord* allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size);
595 size_t tlab_capacity(Thread *thr) const;
596 size_t unsafe_max_tlab_alloc(Thread *thread) const;
597 size_t max_tlab_size() const;
598 size_t tlab_used(Thread* ignored) const;
599
600 void ensure_parsability(bool retire_labs);
601
602 void labs_make_parsable();
603 void tlabs_retire(bool resize);
604 void gclabs_retire(bool resize);
605
606 // ---------- Marking support
607 //
608 private:
609 ShenandoahMarkingContext* _marking_context;
610 MemRegion _bitmap_region;
611 MemRegion _aux_bitmap_region;
612 MarkBitMap _verification_bit_map;
613 MarkBitMap _aux_bit_map;
614
615 size_t _bitmap_size;
616 size_t _bitmap_regions_per_slice;
617 size_t _bitmap_bytes_per_slice;
618
619 size_t _pretouch_heap_page_size;
620 size_t _pretouch_bitmap_page_size;
621
622 bool _bitmap_region_special;
623 bool _aux_bitmap_region_special;
624
625 ShenandoahLiveData** _liveness_cache;
626
627 public:
628 inline ShenandoahMarkingContext* complete_marking_context() const;
629 inline ShenandoahMarkingContext* marking_context() const;
630 inline void mark_complete_marking_context();
631 inline void mark_incomplete_marking_context();
632
633 template<class T>
634 inline void marked_object_iterate(ShenandoahHeapRegion* region, T* cl);
635
636 template<class T>
637 inline void marked_object_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit);
638
639 template<class T>
640 inline void marked_object_oop_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit);
641
642 void reset_mark_bitmap();
643
644 // SATB barriers hooks
645 inline bool requires_marking(const void* entry) const;
646 void force_satb_flush_all_threads();
647
648 // Support for bitmap uncommits
649 bool commit_bitmap_slice(ShenandoahHeapRegion *r);
650 bool uncommit_bitmap_slice(ShenandoahHeapRegion *r);
651 bool is_bitmap_slice_committed(ShenandoahHeapRegion* r, bool skip_self = false);
652
653 // Liveness caching support
654 ShenandoahLiveData* get_liveness_cache(uint worker_id);
655 void flush_liveness_cache(uint worker_id);
656
657 size_t pretouch_heap_page_size() { return _pretouch_heap_page_size; }
658
659 // ---------- Evacuation support
660 //
661 private:
662 ShenandoahCollectionSet* _collection_set;
663 ShenandoahEvacOOMHandler _oom_evac_handler;
664
665 void evacuate_and_update_roots();
666
667 public:
668 static address in_cset_fast_test_addr();
669
670 ShenandoahCollectionSet* collection_set() const { return _collection_set; }
671
672 // Checks if object is in the collection set.
673 inline bool in_collection_set(oop obj) const;
674
675 // Checks if location is in the collection set. Can be interior pointer, not the oop itself.
676 inline bool in_collection_set_loc(void* loc) const;
677
678 // Evacuates object src. Returns the evacuated object, either evacuated
679 // by this thread, or by some other thread.
680 inline oop evacuate_object(oop src, Thread* thread);
681
682 // Call before/after evacuation.
683 inline void enter_evacuation(Thread* t);
684 inline void leave_evacuation(Thread* t);
685
686 // ---------- Helper functions
687 //
688 public:
689 template <class T>
690 inline oop evac_update_with_forwarded(T* p);
691
692 template <class T>
693 inline oop maybe_update_with_forwarded(T* p);
694
695 template <class T>
696 inline oop maybe_update_with_forwarded_not_null(T* p, oop obj);
697
698 template <class T>
699 inline oop update_with_forwarded_not_null(T* p, oop obj);
700
701 static inline oop cas_oop(oop n, narrowOop* addr, oop c);
702 static inline oop cas_oop(oop n, oop* addr, oop c);
703 static inline oop cas_oop(oop n, narrowOop* addr, narrowOop c);
704
705 void trash_humongous_region_at(ShenandoahHeapRegion *r);
706
707 void deduplicate_string(oop str);
708
709 private:
710 void trash_cset_regions();
711 void update_heap_references(bool concurrent);
712
713 // ---------- Testing helpers functions
714 //
715 private:
716 ShenandoahSharedFlag _inject_alloc_failure;
717
718 void try_inject_alloc_failure();
719 bool should_inject_alloc_failure();
720 };
721
722 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_HPP