Mercurial > hg > graal-compiler
annotate src/share/vm/gc_implementation/parallelScavenge/gcTaskManager.hpp @ 1638:b2a00dd3117c
6957084: simplify TaskQueue overflow handling
Reviewed-by: ysr, jmasa
author | jcoomes |
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date | Thu, 01 Jul 2010 21:40:45 -0700 |
parents | c18cbe5936b8 |
children | f95d63e2154a |
rev | line source |
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0 | 1 /* |
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2 * Copyright (c) 2002, 2007, Oracle and/or its affiliates. All rights reserved. |
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
0 | 22 * |
23 */ | |
24 | |
25 // | |
26 // The GCTaskManager is a queue of GCTasks, and accessors | |
27 // to allow the queue to be accessed from many threads. | |
28 // | |
29 | |
30 // Forward declarations of types defined in this file. | |
31 class GCTask; | |
32 class GCTaskQueue; | |
33 class SynchronizedGCTaskQueue; | |
34 class GCTaskManager; | |
35 class NotifyDoneClosure; | |
36 // Some useful subclasses of GCTask. You can also make up your own. | |
37 class NoopGCTask; | |
38 class BarrierGCTask; | |
39 class ReleasingBarrierGCTask; | |
40 class NotifyingBarrierGCTask; | |
41 class WaitForBarrierGCTask; | |
42 // A free list of Monitor*'s. | |
43 class MonitorSupply; | |
44 | |
45 // Forward declarations of classes referenced in this file via pointer. | |
46 class GCTaskThread; | |
47 class Mutex; | |
48 class Monitor; | |
49 class ThreadClosure; | |
50 | |
51 // The abstract base GCTask. | |
52 class GCTask : public ResourceObj { | |
53 public: | |
54 // Known kinds of GCTasks, for predicates. | |
55 class Kind : AllStatic { | |
56 public: | |
57 enum kind { | |
58 unknown_task, | |
59 ordinary_task, | |
60 barrier_task, | |
61 noop_task | |
62 }; | |
63 static const char* to_string(kind value); | |
64 }; | |
65 private: | |
66 // Instance state. | |
67 const Kind::kind _kind; // For runtime type checking. | |
68 const uint _affinity; // Which worker should run task. | |
69 GCTask* _newer; // Tasks are on doubly-linked ... | |
70 GCTask* _older; // ... lists. | |
71 public: | |
72 virtual char* name() { return (char *)"task"; } | |
73 | |
74 // Abstract do_it method | |
75 virtual void do_it(GCTaskManager* manager, uint which) = 0; | |
76 // Accessors | |
77 Kind::kind kind() const { | |
78 return _kind; | |
79 } | |
80 uint affinity() const { | |
81 return _affinity; | |
82 } | |
83 GCTask* newer() const { | |
84 return _newer; | |
85 } | |
86 void set_newer(GCTask* n) { | |
87 _newer = n; | |
88 } | |
89 GCTask* older() const { | |
90 return _older; | |
91 } | |
92 void set_older(GCTask* p) { | |
93 _older = p; | |
94 } | |
95 // Predicates. | |
96 bool is_ordinary_task() const { | |
97 return kind()==Kind::ordinary_task; | |
98 } | |
99 bool is_barrier_task() const { | |
100 return kind()==Kind::barrier_task; | |
101 } | |
102 bool is_noop_task() const { | |
103 return kind()==Kind::noop_task; | |
104 } | |
105 void print(const char* message) const PRODUCT_RETURN; | |
106 protected: | |
107 // Constructors: Only create subclasses. | |
108 // An ordinary GCTask. | |
109 GCTask(); | |
110 // A GCTask of a particular kind, usually barrier or noop. | |
111 GCTask(Kind::kind kind); | |
112 // An ordinary GCTask with an affinity. | |
113 GCTask(uint affinity); | |
114 // A GCTask of a particular kind, with and affinity. | |
115 GCTask(Kind::kind kind, uint affinity); | |
116 // We want a virtual destructor because virtual methods, | |
117 // but since ResourceObj's don't have their destructors | |
118 // called, we don't have one at all. Instead we have | |
119 // this method, which gets called by subclasses to clean up. | |
120 virtual void destruct(); | |
121 // Methods. | |
122 void initialize(); | |
123 }; | |
124 | |
125 // A doubly-linked list of GCTasks. | |
126 // The list is not synchronized, because sometimes we want to | |
127 // build up a list and then make it available to other threads. | |
128 // See also: SynchronizedGCTaskQueue. | |
129 class GCTaskQueue : public ResourceObj { | |
130 private: | |
131 // Instance state. | |
132 GCTask* _insert_end; // Tasks are enqueued at this end. | |
133 GCTask* _remove_end; // Tasks are dequeued from this end. | |
134 uint _length; // The current length of the queue. | |
135 const bool _is_c_heap_obj; // Is this a CHeapObj? | |
136 public: | |
137 // Factory create and destroy methods. | |
138 // Create as ResourceObj. | |
139 static GCTaskQueue* create(); | |
140 // Create as CHeapObj. | |
141 static GCTaskQueue* create_on_c_heap(); | |
142 // Destroyer. | |
143 static void destroy(GCTaskQueue* that); | |
144 // Accessors. | |
145 // These just examine the state of the queue. | |
146 bool is_empty() const { | |
147 assert(((insert_end() == NULL && remove_end() == NULL) || | |
148 (insert_end() != NULL && remove_end() != NULL)), | |
149 "insert_end and remove_end don't match"); | |
150 return insert_end() == NULL; | |
151 } | |
152 uint length() const { | |
153 return _length; | |
154 } | |
155 // Methods. | |
156 // Enqueue one task. | |
157 void enqueue(GCTask* task); | |
158 // Enqueue a list of tasks. Empties the argument list. | |
159 void enqueue(GCTaskQueue* list); | |
160 // Dequeue one task. | |
161 GCTask* dequeue(); | |
162 // Dequeue one task, preferring one with affinity. | |
163 GCTask* dequeue(uint affinity); | |
164 protected: | |
165 // Constructor. Clients use factory, but there might be subclasses. | |
166 GCTaskQueue(bool on_c_heap); | |
167 // Destructor-like method. | |
168 // Because ResourceMark doesn't call destructors. | |
169 // This method cleans up like one. | |
170 virtual void destruct(); | |
171 // Accessors. | |
172 GCTask* insert_end() const { | |
173 return _insert_end; | |
174 } | |
175 void set_insert_end(GCTask* value) { | |
176 _insert_end = value; | |
177 } | |
178 GCTask* remove_end() const { | |
179 return _remove_end; | |
180 } | |
181 void set_remove_end(GCTask* value) { | |
182 _remove_end = value; | |
183 } | |
184 void increment_length() { | |
185 _length += 1; | |
186 } | |
187 void decrement_length() { | |
188 _length -= 1; | |
189 } | |
190 void set_length(uint value) { | |
191 _length = value; | |
192 } | |
193 bool is_c_heap_obj() const { | |
194 return _is_c_heap_obj; | |
195 } | |
196 // Methods. | |
197 void initialize(); | |
198 GCTask* remove(); // Remove from remove end. | |
199 GCTask* remove(GCTask* task); // Remove from the middle. | |
200 void print(const char* message) const PRODUCT_RETURN; | |
201 }; | |
202 | |
203 // A GCTaskQueue that can be synchronized. | |
204 // This "has-a" GCTaskQueue and a mutex to do the exclusion. | |
205 class SynchronizedGCTaskQueue : public CHeapObj { | |
206 private: | |
207 // Instance state. | |
208 GCTaskQueue* _unsynchronized_queue; // Has-a unsynchronized queue. | |
209 Monitor * _lock; // Lock to control access. | |
210 public: | |
211 // Factory create and destroy methods. | |
212 static SynchronizedGCTaskQueue* create(GCTaskQueue* queue, Monitor * lock) { | |
213 return new SynchronizedGCTaskQueue(queue, lock); | |
214 } | |
215 static void destroy(SynchronizedGCTaskQueue* that) { | |
216 if (that != NULL) { | |
217 delete that; | |
218 } | |
219 } | |
220 // Accessors | |
221 GCTaskQueue* unsynchronized_queue() const { | |
222 return _unsynchronized_queue; | |
223 } | |
224 Monitor * lock() const { | |
225 return _lock; | |
226 } | |
227 // GCTaskQueue wrapper methods. | |
228 // These check that you hold the lock | |
229 // and then call the method on the queue. | |
230 bool is_empty() const { | |
231 guarantee(own_lock(), "don't own the lock"); | |
232 return unsynchronized_queue()->is_empty(); | |
233 } | |
234 void enqueue(GCTask* task) { | |
235 guarantee(own_lock(), "don't own the lock"); | |
236 unsynchronized_queue()->enqueue(task); | |
237 } | |
238 void enqueue(GCTaskQueue* list) { | |
239 guarantee(own_lock(), "don't own the lock"); | |
240 unsynchronized_queue()->enqueue(list); | |
241 } | |
242 GCTask* dequeue() { | |
243 guarantee(own_lock(), "don't own the lock"); | |
244 return unsynchronized_queue()->dequeue(); | |
245 } | |
246 GCTask* dequeue(uint affinity) { | |
247 guarantee(own_lock(), "don't own the lock"); | |
248 return unsynchronized_queue()->dequeue(affinity); | |
249 } | |
250 uint length() const { | |
251 guarantee(own_lock(), "don't own the lock"); | |
252 return unsynchronized_queue()->length(); | |
253 } | |
254 // For guarantees. | |
255 bool own_lock() const { | |
256 return lock()->owned_by_self(); | |
257 } | |
258 protected: | |
259 // Constructor. Clients use factory, but there might be subclasses. | |
260 SynchronizedGCTaskQueue(GCTaskQueue* queue, Monitor * lock); | |
261 // Destructor. Not virtual because no virtuals. | |
262 ~SynchronizedGCTaskQueue(); | |
263 }; | |
264 | |
265 // This is an abstract base class for getting notifications | |
266 // when a GCTaskManager is done. | |
267 class NotifyDoneClosure : public CHeapObj { | |
268 public: | |
269 // The notification callback method. | |
270 virtual void notify(GCTaskManager* manager) = 0; | |
271 protected: | |
272 // Constructor. | |
273 NotifyDoneClosure() { | |
274 // Nothing to do. | |
275 } | |
276 // Virtual destructor because virtual methods. | |
277 virtual ~NotifyDoneClosure() { | |
278 // Nothing to do. | |
279 } | |
280 }; | |
281 | |
282 class GCTaskManager : public CHeapObj { | |
283 friend class ParCompactionManager; | |
284 friend class PSParallelCompact; | |
285 friend class PSScavenge; | |
286 friend class PSRefProcTaskExecutor; | |
287 friend class RefProcTaskExecutor; | |
288 private: | |
289 // Instance state. | |
290 NotifyDoneClosure* _ndc; // Notify on completion. | |
291 const uint _workers; // Number of workers. | |
292 Monitor* _monitor; // Notification of changes. | |
293 SynchronizedGCTaskQueue* _queue; // Queue of tasks. | |
294 GCTaskThread** _thread; // Array of worker threads. | |
295 uint _busy_workers; // Number of busy workers. | |
296 uint _blocking_worker; // The worker that's blocking. | |
297 bool* _resource_flag; // Array of flag per threads. | |
298 uint _delivered_tasks; // Count of delivered tasks. | |
299 uint _completed_tasks; // Count of completed tasks. | |
300 uint _barriers; // Count of barrier tasks. | |
301 uint _emptied_queue; // Times we emptied the queue. | |
302 NoopGCTask* _noop_task; // The NoopGCTask instance. | |
303 uint _noop_tasks; // Count of noop tasks. | |
304 public: | |
305 // Factory create and destroy methods. | |
306 static GCTaskManager* create(uint workers) { | |
307 return new GCTaskManager(workers); | |
308 } | |
309 static GCTaskManager* create(uint workers, NotifyDoneClosure* ndc) { | |
310 return new GCTaskManager(workers, ndc); | |
311 } | |
312 static void destroy(GCTaskManager* that) { | |
313 if (that != NULL) { | |
314 delete that; | |
315 } | |
316 } | |
317 // Accessors. | |
318 uint busy_workers() const { | |
319 return _busy_workers; | |
320 } | |
321 // Pun between Monitor* and Mutex* | |
322 Monitor* monitor() const { | |
323 return _monitor; | |
324 } | |
325 Monitor * lock() const { | |
326 return _monitor; | |
327 } | |
328 // Methods. | |
329 // Add the argument task to be run. | |
330 void add_task(GCTask* task); | |
331 // Add a list of tasks. Removes task from the argument list. | |
332 void add_list(GCTaskQueue* list); | |
333 // Claim a task for argument worker. | |
334 GCTask* get_task(uint which); | |
335 // Note the completion of a task by the argument worker. | |
336 void note_completion(uint which); | |
337 // Is the queue blocked from handing out new tasks? | |
338 bool is_blocked() const { | |
339 return (blocking_worker() != sentinel_worker()); | |
340 } | |
341 // Request that all workers release their resources. | |
342 void release_all_resources(); | |
343 // Ask if a particular worker should release its resources. | |
344 bool should_release_resources(uint which); // Predicate. | |
345 // Note the release of resources by the argument worker. | |
346 void note_release(uint which); | |
347 // Constants. | |
348 // A sentinel worker identifier. | |
349 static uint sentinel_worker() { | |
350 return (uint) -1; // Why isn't there a max_uint? | |
351 } | |
352 | |
353 // Execute the task queue and wait for the completion. | |
354 void execute_and_wait(GCTaskQueue* list); | |
355 | |
356 void print_task_time_stamps(); | |
357 void print_threads_on(outputStream* st); | |
358 void threads_do(ThreadClosure* tc); | |
359 | |
360 protected: | |
361 // Constructors. Clients use factory, but there might be subclasses. | |
362 // Create a GCTaskManager with the appropriate number of workers. | |
363 GCTaskManager(uint workers); | |
364 // Create a GCTaskManager that calls back when there's no more work. | |
365 GCTaskManager(uint workers, NotifyDoneClosure* ndc); | |
366 // Make virtual if necessary. | |
367 ~GCTaskManager(); | |
368 // Accessors. | |
369 uint workers() const { | |
370 return _workers; | |
371 } | |
372 NotifyDoneClosure* notify_done_closure() const { | |
373 return _ndc; | |
374 } | |
375 SynchronizedGCTaskQueue* queue() const { | |
376 return _queue; | |
377 } | |
378 NoopGCTask* noop_task() const { | |
379 return _noop_task; | |
380 } | |
381 // Bounds-checking per-thread data accessors. | |
382 GCTaskThread* thread(uint which); | |
383 void set_thread(uint which, GCTaskThread* value); | |
384 bool resource_flag(uint which); | |
385 void set_resource_flag(uint which, bool value); | |
386 // Modifier methods with some semantics. | |
387 // Is any worker blocking handing out new tasks? | |
388 uint blocking_worker() const { | |
389 return _blocking_worker; | |
390 } | |
391 void set_blocking_worker(uint value) { | |
392 _blocking_worker = value; | |
393 } | |
394 void set_unblocked() { | |
395 set_blocking_worker(sentinel_worker()); | |
396 } | |
397 // Count of busy workers. | |
398 void reset_busy_workers() { | |
399 _busy_workers = 0; | |
400 } | |
401 uint increment_busy_workers(); | |
402 uint decrement_busy_workers(); | |
403 // Count of tasks delivered to workers. | |
404 uint delivered_tasks() const { | |
405 return _delivered_tasks; | |
406 } | |
407 void increment_delivered_tasks() { | |
408 _delivered_tasks += 1; | |
409 } | |
410 void reset_delivered_tasks() { | |
411 _delivered_tasks = 0; | |
412 } | |
413 // Count of tasks completed by workers. | |
414 uint completed_tasks() const { | |
415 return _completed_tasks; | |
416 } | |
417 void increment_completed_tasks() { | |
418 _completed_tasks += 1; | |
419 } | |
420 void reset_completed_tasks() { | |
421 _completed_tasks = 0; | |
422 } | |
423 // Count of barrier tasks completed. | |
424 uint barriers() const { | |
425 return _barriers; | |
426 } | |
427 void increment_barriers() { | |
428 _barriers += 1; | |
429 } | |
430 void reset_barriers() { | |
431 _barriers = 0; | |
432 } | |
433 // Count of how many times the queue has emptied. | |
434 uint emptied_queue() const { | |
435 return _emptied_queue; | |
436 } | |
437 void increment_emptied_queue() { | |
438 _emptied_queue += 1; | |
439 } | |
440 void reset_emptied_queue() { | |
441 _emptied_queue = 0; | |
442 } | |
443 // Count of the number of noop tasks we've handed out, | |
444 // e.g., to handle resource release requests. | |
445 uint noop_tasks() const { | |
446 return _noop_tasks; | |
447 } | |
448 void increment_noop_tasks() { | |
449 _noop_tasks += 1; | |
450 } | |
451 void reset_noop_tasks() { | |
452 _noop_tasks = 0; | |
453 } | |
454 // Other methods. | |
455 void initialize(); | |
456 }; | |
457 | |
458 // | |
459 // Some exemplary GCTasks. | |
460 // | |
461 | |
462 // A noop task that does nothing, | |
463 // except take us around the GCTaskThread loop. | |
464 class NoopGCTask : public GCTask { | |
465 private: | |
466 const bool _is_c_heap_obj; // Is this a CHeapObj? | |
467 public: | |
468 // Factory create and destroy methods. | |
469 static NoopGCTask* create(); | |
470 static NoopGCTask* create_on_c_heap(); | |
471 static void destroy(NoopGCTask* that); | |
472 // Methods from GCTask. | |
473 void do_it(GCTaskManager* manager, uint which) { | |
474 // Nothing to do. | |
475 } | |
476 protected: | |
477 // Constructor. | |
478 NoopGCTask(bool on_c_heap) : | |
479 GCTask(GCTask::Kind::noop_task), | |
480 _is_c_heap_obj(on_c_heap) { | |
481 // Nothing to do. | |
482 } | |
483 // Destructor-like method. | |
484 void destruct(); | |
485 // Accessors. | |
486 bool is_c_heap_obj() const { | |
487 return _is_c_heap_obj; | |
488 } | |
489 }; | |
490 | |
491 // A BarrierGCTask blocks other tasks from starting, | |
492 // and waits until it is the only task running. | |
493 class BarrierGCTask : public GCTask { | |
494 public: | |
495 // Factory create and destroy methods. | |
496 static BarrierGCTask* create() { | |
497 return new BarrierGCTask(); | |
498 } | |
499 static void destroy(BarrierGCTask* that) { | |
500 if (that != NULL) { | |
501 that->destruct(); | |
502 delete that; | |
503 } | |
504 } | |
505 // Methods from GCTask. | |
506 void do_it(GCTaskManager* manager, uint which); | |
507 protected: | |
508 // Constructor. Clients use factory, but there might be subclasses. | |
509 BarrierGCTask() : | |
510 GCTask(GCTask::Kind::barrier_task) { | |
511 // Nothing to do. | |
512 } | |
513 // Destructor-like method. | |
514 void destruct(); | |
515 // Methods. | |
516 // Wait for this to be the only task running. | |
517 void do_it_internal(GCTaskManager* manager, uint which); | |
518 }; | |
519 | |
520 // A ReleasingBarrierGCTask is a BarrierGCTask | |
521 // that tells all the tasks to release their resource areas. | |
522 class ReleasingBarrierGCTask : public BarrierGCTask { | |
523 public: | |
524 // Factory create and destroy methods. | |
525 static ReleasingBarrierGCTask* create() { | |
526 return new ReleasingBarrierGCTask(); | |
527 } | |
528 static void destroy(ReleasingBarrierGCTask* that) { | |
529 if (that != NULL) { | |
530 that->destruct(); | |
531 delete that; | |
532 } | |
533 } | |
534 // Methods from GCTask. | |
535 void do_it(GCTaskManager* manager, uint which); | |
536 protected: | |
537 // Constructor. Clients use factory, but there might be subclasses. | |
538 ReleasingBarrierGCTask() : | |
539 BarrierGCTask() { | |
540 // Nothing to do. | |
541 } | |
542 // Destructor-like method. | |
543 void destruct(); | |
544 }; | |
545 | |
546 // A NotifyingBarrierGCTask is a BarrierGCTask | |
547 // that calls a notification method when it is the only task running. | |
548 class NotifyingBarrierGCTask : public BarrierGCTask { | |
549 private: | |
550 // Instance state. | |
551 NotifyDoneClosure* _ndc; // The callback object. | |
552 public: | |
553 // Factory create and destroy methods. | |
554 static NotifyingBarrierGCTask* create(NotifyDoneClosure* ndc) { | |
555 return new NotifyingBarrierGCTask(ndc); | |
556 } | |
557 static void destroy(NotifyingBarrierGCTask* that) { | |
558 if (that != NULL) { | |
559 that->destruct(); | |
560 delete that; | |
561 } | |
562 } | |
563 // Methods from GCTask. | |
564 void do_it(GCTaskManager* manager, uint which); | |
565 protected: | |
566 // Constructor. Clients use factory, but there might be subclasses. | |
567 NotifyingBarrierGCTask(NotifyDoneClosure* ndc) : | |
568 BarrierGCTask(), | |
569 _ndc(ndc) { | |
570 assert(notify_done_closure() != NULL, "can't notify on NULL"); | |
571 } | |
572 // Destructor-like method. | |
573 void destruct(); | |
574 // Accessor. | |
575 NotifyDoneClosure* notify_done_closure() const { return _ndc; } | |
576 }; | |
577 | |
578 // A WaitForBarrierGCTask is a BarrierGCTask | |
579 // with a method you can call to wait until | |
580 // the BarrierGCTask is done. | |
581 // This may cover many of the uses of NotifyingBarrierGCTasks. | |
582 class WaitForBarrierGCTask : public BarrierGCTask { | |
583 private: | |
584 // Instance state. | |
585 Monitor* _monitor; // Guard and notify changes. | |
586 bool _should_wait; // true=>wait, false=>proceed. | |
587 const bool _is_c_heap_obj; // Was allocated on the heap. | |
588 public: | |
589 virtual char* name() { return (char *) "waitfor-barrier-task"; } | |
590 | |
591 // Factory create and destroy methods. | |
592 static WaitForBarrierGCTask* create(); | |
593 static WaitForBarrierGCTask* create_on_c_heap(); | |
594 static void destroy(WaitForBarrierGCTask* that); | |
595 // Methods. | |
596 void do_it(GCTaskManager* manager, uint which); | |
597 void wait_for(); | |
598 protected: | |
599 // Constructor. Clients use factory, but there might be subclasses. | |
600 WaitForBarrierGCTask(bool on_c_heap); | |
601 // Destructor-like method. | |
602 void destruct(); | |
603 // Accessors. | |
604 Monitor* monitor() const { | |
605 return _monitor; | |
606 } | |
607 bool should_wait() const { | |
608 return _should_wait; | |
609 } | |
610 void set_should_wait(bool value) { | |
611 _should_wait = value; | |
612 } | |
613 bool is_c_heap_obj() { | |
614 return _is_c_heap_obj; | |
615 } | |
616 }; | |
617 | |
618 class MonitorSupply : public AllStatic { | |
619 private: | |
620 // State. | |
621 // Control multi-threaded access. | |
622 static Mutex* _lock; | |
623 // The list of available Monitor*'s. | |
624 static GrowableArray<Monitor*>* _freelist; | |
625 public: | |
626 // Reserve a Monitor*. | |
627 static Monitor* reserve(); | |
628 // Release a Monitor*. | |
629 static void release(Monitor* instance); | |
630 private: | |
631 // Accessors. | |
632 static Mutex* lock() { | |
633 return _lock; | |
634 } | |
635 static GrowableArray<Monitor*>* freelist() { | |
636 return _freelist; | |
637 } | |
638 }; |