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/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 ShenandoahAllocTracker;
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 ShenandoahObjectMarker;
61 class ShenandoahPacer;
62 class ShenandoahTraversalGC;
63 class ShenandoahVerifier;
64 class ShenandoahWorkGang;
65 class VMStructs;
66
67 class ShenandoahRegionIterator : public StackObj {
68 private:
69 ShenandoahHeap* _heap;
70
71 DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile size_t));
72 volatile size_t _index;
73 DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, 0);
74
75 // No implicit copying: iterators should be passed by reference to capture the state
76 NONCOPYABLE(ShenandoahRegionIterator);
77
78 public:
79 ShenandoahRegionIterator();
80 ShenandoahRegionIterator(ShenandoahHeap* heap);
81
82 // Reset iterator to default state
83 void reset();
84
85 // Returns next region, or NULL if there are no more regions.
86 // This is multi-thread-safe.
87 inline ShenandoahHeapRegion* next();
88
89 // This is *not* MT safe. However, in the absence of multithreaded access, it
90 // can be used to determine if there is more work to do.
91 bool has_next() const;
92 };
93
94 class ShenandoahHeapRegionClosure : public StackObj {
95 public:
96 virtual void heap_region_do(ShenandoahHeapRegion* r) = 0;
97 virtual bool is_thread_safe() { return false; }
98 };
99
100 #ifdef ASSERT
101 class ShenandoahAssertToSpaceClosure : public OopClosure {
102 private:
103 template <class T>
104 void do_oop_work(T* p);
105 public:
106 void do_oop(narrowOop* p);
107 void do_oop(oop* p);
108 };
109 #endif
110
111 typedef ShenandoahLock ShenandoahHeapLock;
112 typedef ShenandoahLocker ShenandoahHeapLocker;
113
114 // Shenandoah GC is low-pause concurrent GC that uses Brooks forwarding pointers
115 // to encode forwarding data. See BrooksPointer for details on forwarding data encoding.
116 // See ShenandoahControlThread for GC cycle structure.
117 //
118 class ShenandoahHeap : public CollectedHeap {
119 friend class ShenandoahAsserts;
120 friend class VMStructs;
121 friend class ShenandoahGCSession;
122 friend class ShenandoahGCStateResetter;
123 friend class ShenandoahObjectMarker;
124
125 // ---------- Locks that guard important data structures in Heap
126 //
127 private:
128 ShenandoahHeapLock _lock;
129
130 public:
131 ShenandoahHeapLock* lock() {
132 return &_lock;
133 }
134
135 void assert_heaplock_owned_by_current_thread() NOT_DEBUG_RETURN;
136 void assert_heaplock_not_owned_by_current_thread() NOT_DEBUG_RETURN;
137 void assert_heaplock_or_safepoint() NOT_DEBUG_RETURN;
138
139 // ---------- Initialization, termination, identification, printing routines
140 //
141 public:
142 static ShenandoahHeap* heap();
143 static ShenandoahHeap* heap_no_check();
144
145 const char* name() const { return "Shenandoah"; }
146 ShenandoahHeap::Name kind() const { return CollectedHeap::Shenandoah; }
147
148 ShenandoahHeap(ShenandoahCollectorPolicy* policy);
149 jint initialize();
150 void post_initialize();
151 void initialize_heuristics();
152
153 void initialize_serviceability();
154
155 void print_on(outputStream* st) const;
156 void print_extended_on(outputStream *st) const;
157 void print_tracing_info() const;
158 void print_gc_threads_on(outputStream* st) const;
159 void print_heap_regions_on(outputStream* st) const;
160
161 void stop();
162
163 void prepare_for_verify();
164 void verify(VerifyOption vo);
165
166 // ---------- Heap counters and metrics
167 //
168 private:
169 size_t _initial_size;
170 size_t _minimum_size;
171 DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile size_t));
172 volatile size_t _used;
173 volatile size_t _committed;
174 volatile size_t _bytes_allocated_since_gc_start;
175 DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, 0);
176
177 public:
178 void increase_used(size_t bytes);
179 void decrease_used(size_t bytes);
180 void set_used(size_t bytes);
181
182 void increase_committed(size_t bytes);
183 void decrease_committed(size_t bytes);
184 void increase_allocated(size_t bytes);
185
186 size_t bytes_allocated_since_gc_start();
187 void reset_bytes_allocated_since_gc_start();
188
189 size_t min_capacity() const;
190 size_t max_capacity() const;
191 size_t initial_capacity() const;
192 size_t capacity() const;
193 size_t used() const;
194 size_t committed() const;
195
196 // ---------- Workers handling
197 //
198 private:
199 uint _max_workers;
200 ShenandoahWorkGang* _workers;
201 ShenandoahWorkGang* _safepoint_workers;
202
203 public:
204 uint max_workers();
205 void assert_gc_workers(uint nworker) NOT_DEBUG_RETURN;
206
207 WorkGang* workers() const;
208 WorkGang* get_safepoint_workers();
209
210 void gc_threads_do(ThreadClosure* tcl) const;
211
212 // ---------- Heap regions handling machinery
213 //
214 private:
215 MemRegion _heap_region;
216 bool _heap_region_special;
217 size_t _num_regions;
218 ShenandoahHeapRegion** _regions;
219 ShenandoahRegionIterator _update_refs_iterator;
220
221 public:
222
223 inline HeapWord* base() const { return _heap_region.start(); }
224
225 inline size_t num_regions() const { return _num_regions; }
226 inline bool is_heap_region_special() { return _heap_region_special; }
227
228 inline ShenandoahHeapRegion* const heap_region_containing(const void* addr) const;
229 inline size_t heap_region_index_containing(const void* addr) const;
230
231 inline ShenandoahHeapRegion* const get_region(size_t region_idx) const;
232
233 void heap_region_iterate(ShenandoahHeapRegionClosure* blk) const;
234 void parallel_heap_region_iterate(ShenandoahHeapRegionClosure* blk) const;
235
236 // ---------- GC state machinery
237 //
238 // GC state describes the important parts of collector state, that may be
239 // used to make barrier selection decisions in the native and generated code.
240 // Multiple bits can be set at once.
241 //
242 // Important invariant: when GC state is zero, the heap is stable, and no barriers
243 // are required.
244 //
245 public:
246 enum GCStateBitPos {
247 // Heap has forwarded objects: needs LRB barriers.
248 HAS_FORWARDED_BITPOS = 0,
249
250 // Heap is under marking: needs SATB barriers.
251 MARKING_BITPOS = 1,
252
253 // Heap is under evacuation: needs LRB barriers. (Set together with HAS_FORWARDED)
254 EVACUATION_BITPOS = 2,
255
256 // Heap is under updating: needs no additional barriers.
257 UPDATEREFS_BITPOS = 3,
258
259 // Heap is under traversal collection
260 TRAVERSAL_BITPOS = 4
261 };
262
263 enum GCState {
264 STABLE = 0,
265 HAS_FORWARDED = 1 << HAS_FORWARDED_BITPOS,
266 MARKING = 1 << MARKING_BITPOS,
267 EVACUATION = 1 << EVACUATION_BITPOS,
268 UPDATEREFS = 1 << UPDATEREFS_BITPOS,
269 TRAVERSAL = 1 << TRAVERSAL_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_concurrent_traversal_in_progress(bool in_progress);
294 void set_has_forwarded_objects(bool cond);
295 void set_concurrent_root_in_progress(bool cond);
296
297 inline bool is_stable() const;
298 inline bool is_idle() const;
299 inline bool is_concurrent_mark_in_progress() const;
300 inline bool is_update_refs_in_progress() const;
301 inline bool is_evacuation_in_progress() const;
302 inline bool is_degenerated_gc_in_progress() const;
303 inline bool is_full_gc_in_progress() const;
304 inline bool is_full_gc_move_in_progress() const;
305 inline bool is_concurrent_traversal_in_progress() const;
306 inline bool has_forwarded_objects() const;
307 inline bool is_gc_in_progress_mask(uint mask) const;
308 inline bool is_stw_gc_in_progress() const;
309 inline bool is_concurrent_root_in_progress() const;
310
311 // ---------- GC cancellation and degeneration machinery
312 //
313 // Cancelled GC flag is used to notify concurrent phases that they should terminate.
314 //
315 public:
316 enum ShenandoahDegenPoint {
317 _degenerated_unset,
318 _degenerated_traversal,
319 _degenerated_outside_cycle,
320 _degenerated_mark,
321 _degenerated_evac,
322 _degenerated_updaterefs,
323 _DEGENERATED_LIMIT
324 };
325
326 static const char* degen_point_to_string(ShenandoahDegenPoint point) {
327 switch (point) {
328 case _degenerated_unset:
329 return "<UNSET>";
330 case _degenerated_traversal:
331 return "Traversal";
332 case _degenerated_outside_cycle:
333 return "Outside of Cycle";
334 case _degenerated_mark:
335 return "Mark";
336 case _degenerated_evac:
337 return "Evacuation";
338 case _degenerated_updaterefs:
339 return "Update Refs";
340 default:
341 ShouldNotReachHere();
342 return "ERROR";
343 }
344 };
345
346 private:
347 enum CancelState {
348 // Normal state. GC has not been cancelled and is open for cancellation.
349 // Worker threads can suspend for safepoint.
350 CANCELLABLE,
351
352 // GC has been cancelled. Worker threads can not suspend for
353 // safepoint but must finish their work as soon as possible.
354 CANCELLED,
355
356 // GC has not been cancelled and must not be cancelled. At least
357 // one worker thread checks for pending safepoint and may suspend
358 // if a safepoint is pending.
359 NOT_CANCELLED
360 };
361
362 ShenandoahSharedEnumFlag<CancelState> _cancelled_gc;
363 bool try_cancel_gc();
364
365 public:
366 static address cancelled_gc_addr();
367
368 inline bool cancelled_gc() const;
369 inline bool check_cancelled_gc_and_yield(bool sts_active = true);
370
371 inline void clear_cancelled_gc();
372
373 void cancel_gc(GCCause::Cause cause);
374
375 // ---------- GC operations entry points
376 //
377 public:
378 // Entry points to STW GC operations, these cause a related safepoint, that then
379 // call the entry method below
380 void vmop_entry_init_mark();
381 void vmop_entry_final_mark();
382 void vmop_entry_final_evac();
383 void vmop_entry_init_updaterefs();
384 void vmop_entry_final_updaterefs();
385 void vmop_entry_init_traversal();
386 void vmop_entry_final_traversal();
387 void vmop_entry_full(GCCause::Cause cause);
388 void vmop_degenerated(ShenandoahDegenPoint point);
389
390 // Entry methods to normally STW GC operations. These set up logging, monitoring
391 // and workers for net VM operation
392 void entry_init_mark();
393 void entry_final_mark();
394 void entry_final_evac();
395 void entry_init_updaterefs();
396 void entry_final_updaterefs();
397 void entry_init_traversal();
398 void entry_final_traversal();
399 void entry_full(GCCause::Cause cause);
400 void entry_degenerated(int point);
401
402 // Entry methods to normally concurrent GC operations. These set up logging, monitoring
403 // for concurrent operation.
404 void entry_reset();
405 void entry_mark();
406 void entry_preclean();
407 void entry_roots();
408 void entry_cleanup();
409 void entry_evac();
410 void entry_updaterefs();
411 void entry_traversal();
412 void entry_uncommit(double shrink_before);
413
414 private:
415 // Actual work for the phases
416 void op_init_mark();
417 void op_final_mark();
418 void op_final_evac();
419 void op_init_updaterefs();
420 void op_final_updaterefs();
421 void op_init_traversal();
422 void op_final_traversal();
423 void op_full(GCCause::Cause cause);
424 void op_degenerated(ShenandoahDegenPoint point);
425 void op_degenerated_fail();
426 void op_degenerated_futile();
427
428 void op_reset();
429 void op_mark();
430 void op_preclean();
431 void op_roots();
432 void op_cleanup();
433 void op_conc_evac();
434 void op_stw_evac();
435 void op_updaterefs();
436 void op_traversal();
437 void op_uncommit(double shrink_before);
438
439 // Messages for GC trace events, they have to be immortal for
440 // passing around the logging/tracing systems
441 const char* init_mark_event_message() const;
442 const char* final_mark_event_message() const;
443 const char* conc_mark_event_message() const;
444 const char* init_traversal_event_message() const;
445 const char* final_traversal_event_message() const;
446 const char* conc_traversal_event_message() const;
447 const char* degen_event_message(ShenandoahDegenPoint point) const;
448
449 // ---------- GC subsystems
450 //
451 private:
452 ShenandoahControlThread* _control_thread;
453 ShenandoahCollectorPolicy* _shenandoah_policy;
454 ShenandoahMode* _gc_mode;
455 ShenandoahHeuristics* _heuristics;
456 ShenandoahFreeSet* _free_set;
457 ShenandoahConcurrentMark* _scm;
458 ShenandoahTraversalGC* _traversal_gc;
459 ShenandoahMarkCompact* _full_gc;
460 ShenandoahPacer* _pacer;
461 ShenandoahVerifier* _verifier;
462
463 ShenandoahAllocTracker* _alloc_tracker;
464 ShenandoahPhaseTimings* _phase_timings;
465
466 ShenandoahControlThread* control_thread() { return _control_thread; }
467 ShenandoahMarkCompact* full_gc() { return _full_gc; }
468
469 public:
470 ShenandoahCollectorPolicy* shenandoah_policy() const { return _shenandoah_policy; }
471 ShenandoahHeuristics* heuristics() const { return _heuristics; }
472 ShenandoahFreeSet* free_set() const { return _free_set; }
473 ShenandoahConcurrentMark* concurrent_mark() { return _scm; }
474 ShenandoahTraversalGC* traversal_gc() const { return _traversal_gc; }
475 bool is_traversal_mode() const { return _traversal_gc != NULL; }
476 ShenandoahPacer* pacer() const { return _pacer; }
477
478 ShenandoahPhaseTimings* phase_timings() const { return _phase_timings; }
479 ShenandoahAllocTracker* alloc_tracker() const { return _alloc_tracker; }
480
481 ShenandoahVerifier* verifier();
482
483 // ---------- VM subsystem bindings
484 //
485 private:
486 ShenandoahMonitoringSupport* _monitoring_support;
487 MemoryPool* _memory_pool;
488 GCMemoryManager _stw_memory_manager;
489 GCMemoryManager _cycle_memory_manager;
490 ConcurrentGCTimer* _gc_timer;
491 SoftRefPolicy _soft_ref_policy;
492
493 // For exporting to SA
494 int _log_min_obj_alignment_in_bytes;
495 public:
496 ShenandoahMonitoringSupport* monitoring_support() { return _monitoring_support; }
497 GCMemoryManager* cycle_memory_manager() { return &_cycle_memory_manager; }
498 GCMemoryManager* stw_memory_manager() { return &_stw_memory_manager; }
499 SoftRefPolicy* soft_ref_policy() { return &_soft_ref_policy; }
500
501 GrowableArray<GCMemoryManager*> memory_managers();
502 GrowableArray<MemoryPool*> memory_pools();
503 MemoryUsage memory_usage();
504 GCTracer* tracer();
505 GCTimer* gc_timer() const;
506
507 // ---------- Reference processing
508 //
509 private:
510 AlwaysTrueClosure _subject_to_discovery;
511 ReferenceProcessor* _ref_processor;
512 ShenandoahSharedFlag _process_references;
513
514 void ref_processing_init();
515
516 public:
517 ReferenceProcessor* ref_processor() { return _ref_processor; }
518 void set_process_references(bool pr);
519 bool process_references() const;
520
521 // ---------- Class Unloading
522 //
523 private:
524 ShenandoahSharedFlag _unload_classes;
525 ShenandoahUnload _unloader;
526
527 public:
528 void set_unload_classes(bool uc);
529 bool unload_classes() const;
530
531 // Perform STW class unloading and weak root cleaning
532 void parallel_cleaning(bool full_gc);
533
534 private:
535 void stw_unload_classes(bool full_gc);
536 void stw_process_weak_roots(bool full_gc);
537
538 // Prepare concurrent root processing
539 void prepare_concurrent_roots();
540 // Prepare and finish concurrent unloading
541 void prepare_concurrent_unloading();
542 void finish_concurrent_unloading();
543
544 // ---------- Generic interface hooks
545 // Minor things that super-interface expects us to implement to play nice with
546 // the rest of runtime. Some of the things here are not required to be implemented,
547 // and can be stubbed out.
548 //
549 public:
550 AdaptiveSizePolicy* size_policy() shenandoah_not_implemented_return(NULL);
551 bool is_maximal_no_gc() const shenandoah_not_implemented_return(false);
552
553 bool is_in(const void* p) const;
554
555 MemRegion reserved_region() const { return _reserved; }
556 bool is_in_reserved(const void* addr) const { return _reserved.contains(addr); }
557
558 void collect(GCCause::Cause cause);
559 void do_full_collection(bool clear_all_soft_refs);
560
561 // Used for parsing heap during error printing
562 HeapWord* block_start(const void* addr) const;
563 bool block_is_obj(const HeapWord* addr) const;
564 bool print_location(outputStream* st, void* addr) const;
565
566 ObjectMarker* object_marker();
567 // Used for native heap walkers: heap dumpers, mostly
568 void object_iterate(ObjectClosure* cl);
569
570 // Keep alive an object that was loaded with AS_NO_KEEPALIVE.
571 void keep_alive(oop obj);
572
573 // Used by RMI
574 jlong millis_since_last_gc();
575
576 // ---------- Safepoint interface hooks
577 //
578 public:
579 void safepoint_synchronize_begin();
580 void safepoint_synchronize_end();
581
582 // ---------- Code roots handling hooks
583 //
584 public:
585 void register_nmethod(nmethod* nm);
586 void unregister_nmethod(nmethod* nm);
587 void flush_nmethod(nmethod* nm);
588 void verify_nmethod(nmethod* nm) {}
589
590 // ---------- Pinning hooks
591 //
592 public:
593 // Shenandoah supports per-object (per-region) pinning
594 bool supports_object_pinning() const { return true; }
595
596 oop pin_object(JavaThread* thread, oop obj);
597 void unpin_object(JavaThread* thread, oop obj);
598
599 void sync_pinned_region_status();
600 void assert_pinned_region_status() NOT_DEBUG_RETURN;
601
602 // ---------- Allocation support
603 //
604 private:
605 HeapWord* allocate_memory_under_lock(ShenandoahAllocRequest& request, bool& in_new_region);
606 inline HeapWord* allocate_from_gclab(Thread* thread, size_t size);
607 HeapWord* allocate_from_gclab_slow(Thread* thread, size_t size);
608 HeapWord* allocate_new_gclab(size_t min_size, size_t word_size, size_t* actual_size);
609 void retire_and_reset_gclabs();
610
611 public:
612 HeapWord* allocate_memory(ShenandoahAllocRequest& request);
613 HeapWord* mem_allocate(size_t size, bool* what);
614 MetaWord* satisfy_failed_metadata_allocation(ClassLoaderData* loader_data,
615 size_t size,
616 Metaspace::MetadataType mdtype);
617
618 void notify_mutator_alloc_words(size_t words, bool waste);
619
620 // Shenandoah supports TLAB allocation
621 bool supports_tlab_allocation() const { return true; }
622
623 HeapWord* allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size);
624 size_t tlab_capacity(Thread *thr) const;
625 size_t unsafe_max_tlab_alloc(Thread *thread) const;
626 size_t max_tlab_size() const;
627 size_t tlab_used(Thread* ignored) const;
628
629 void resize_tlabs();
630
631 void ensure_parsability(bool retire_tlabs);
632 void make_parsable(bool retire_tlabs);
633
634 // ---------- Marking support
635 //
636 private:
637 ShenandoahMarkingContext* _marking_context;
638 MemRegion _bitmap_region;
639 MemRegion _aux_bitmap_region;
640 MarkBitMap _verification_bit_map;
641 MarkBitMap _aux_bit_map;
642
643 size_t _bitmap_size;
644 size_t _bitmap_regions_per_slice;
645 size_t _bitmap_bytes_per_slice;
646
647 bool _bitmap_region_special;
648 bool _aux_bitmap_region_special;
649
650 // Used for buffering per-region liveness data.
651 // Needed since ShenandoahHeapRegion uses atomics to update liveness.
652 //
653 // The array has max-workers elements, each of which is an array of
654 // jushort * max_regions. The choice of jushort is not accidental:
655 // there is a tradeoff between static/dynamic footprint that translates
656 // into cache pressure (which is already high during marking), and
657 // too many atomic updates. size_t/jint is too large, jbyte is too small.
658 jushort** _liveness_cache;
659
660 private:
661 bool commit_aux_bitmap();
662 void uncommit_aux_bit_map();
663
664 public:
665 inline ShenandoahMarkingContext* complete_marking_context() const;
666 inline ShenandoahMarkingContext* marking_context() const;
667 inline void mark_complete_marking_context();
668 inline void mark_incomplete_marking_context();
669
670 template<class T>
671 inline void marked_object_iterate(ShenandoahHeapRegion* region, T* cl);
672
673 template<class T>
674 inline void marked_object_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit);
675
676 template<class T>
677 inline void marked_object_oop_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit);
678
679 void reset_mark_bitmap();
680
681 // SATB barriers hooks
682 template<bool RESOLVE>
683 inline bool requires_marking(const void* entry) const;
684 void force_satb_flush_all_threads();
685
686 // Support for bitmap uncommits
687 bool commit_bitmap_slice(ShenandoahHeapRegion *r);
688 bool uncommit_bitmap_slice(ShenandoahHeapRegion *r);
689 bool is_bitmap_slice_committed(ShenandoahHeapRegion* r, bool skip_self = false);
690
691 // Liveness caching support
692 jushort* get_liveness_cache(uint worker_id);
693 void flush_liveness_cache(uint worker_id);
694
695 // ---------- Evacuation support
696 //
697 private:
698 ShenandoahCollectionSet* _collection_set;
699 ShenandoahEvacOOMHandler _oom_evac_handler;
700
701 void evacuate_and_update_roots();
702
703 public:
704 static address in_cset_fast_test_addr();
705
706 ShenandoahCollectionSet* collection_set() const { return _collection_set; }
707
708 // Checks if object is in the collection set.
709 inline bool in_collection_set(oop obj) const;
710
711 // Checks if location is in the collection set. Can be interior pointer, not the oop itself.
712 inline bool in_collection_set_loc(void* loc) const;
713
714 // Evacuates object src. Returns the evacuated object, either evacuated
715 // by this thread, or by some other thread.
716 inline oop evacuate_object(oop src, Thread* thread);
717
718 // Call before/after evacuation.
719 void enter_evacuation();
720 void leave_evacuation();
721
722 // ---------- Helper functions
723 //
724 public:
725 template <class T>
726 inline oop evac_update_with_forwarded(T* p);
727
728 template <class T>
729 inline oop maybe_update_with_forwarded(T* p);
730
731 template <class T>
732 inline oop maybe_update_with_forwarded_not_null(T* p, oop obj);
733
734 template <class T>
735 inline oop update_with_forwarded_not_null(T* p, oop obj);
736
737 static inline oop cas_oop(oop n, narrowOop* addr, oop c);
738 static inline oop cas_oop(oop n, oop* addr, oop c);
739 static inline oop cas_oop(oop n, narrowOop* addr, narrowOop c);
740
741 void trash_humongous_region_at(ShenandoahHeapRegion *r);
742
743 void deduplicate_string(oop str);
744
745 private:
746 void trash_cset_regions();
747 void update_heap_references(bool concurrent);
748
749 // ---------- Testing helpers functions
750 //
751 private:
752 ShenandoahSharedFlag _inject_alloc_failure;
753
754 void try_inject_alloc_failure();
755 bool should_inject_alloc_failure();
756 };
757
758 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_HPP