-
Notifications
You must be signed in to change notification settings - Fork 63
/
tpi_tnycthrd.c
842 lines (695 loc) · 27.6 KB
/
tpi_tnycthrd.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* */
/* This file is part of the program and library */
/* SCIP --- Solving Constraint Integer Programs */
/* */
/* Copyright (c) 2002-2024 Zuse Institute Berlin (ZIB) */
/* */
/* Licensed under the Apache License, Version 2.0 (the "License"); */
/* you may not use this file except in compliance with the License. */
/* You may obtain a copy of the License at */
/* */
/* http://www.apache.org/licenses/LICENSE-2.0 */
/* */
/* Unless required by applicable law or agreed to in writing, software */
/* distributed under the License is distributed on an "AS IS" BASIS, */
/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */
/* See the License for the specific language governing permissions and */
/* limitations under the License. */
/* */
/* You should have received a copy of the Apache-2.0 license */
/* along with SCIP; see the file LICENSE. If not visit scipopt.org. */
/* */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/**@file tpi_tnycthrd.c
* @ingroup TASKINTERFACE
* @brief a TPI implementation using tinycthreads
* @author Stephen J. Maher
* @author Leona Gottwald
* @author Marc Pfetsch
*/
/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
#include "tpi/tpi.h"
#include "blockmemshell/memory.h"
#include "tinycthread/tinycthread.h"
#include "scip/pub_message.h"
/* macros for direct access */
/* lock */
#define SCIPtnyInitLock(lock) ( mtx_init((lock), mtx_plain) == thrd_success ? SCIP_OKAY : SCIP_ERROR )
#define SCIPtnyDestroyLock(lock) ( mtx_destroy(lock) )
#define SCIPtnyAcquireLock(lock) ( mtx_lock(lock) == thrd_success ? SCIP_OKAY : SCIP_ERROR )
#define SCIPtnyReleaseLock(lock) ( mtx_unlock(lock) == thrd_success ? SCIP_OKAY : SCIP_ERROR )
/* condition */
#define SCIPtnyInitCondition(condition) ( cnd_init(condition) == thrd_success ? SCIP_OKAY : SCIP_ERROR )
#define SCIPtnyDestroyCondition(condition) ( cnd_destroy(condition) )
#define SCIPtnySignalCondition(condition) ( cnd_signal(condition) == thrd_success ? SCIP_OKAY : SCIP_ERROR )
#define SCIPtnyBroadcastCondition(condition) ( cnd_broadcast(condition) == thrd_success ? SCIP_OKAY : SCIP_ERROR )
#define SCIPtnyWaitCondition(condition, lock) ( cnd_wait((condition), (lock)) == thrd_success ? SCIP_OKAY: SCIP_ERROR )
/** struct containing lock */
struct SCIP_Lock
{
mtx_t lock;
};
/** struct containing condition */
struct SCIP_Condition
{
cnd_t condition;
};
typedef struct SCIP_ThreadPool SCIP_THREADPOOL;
static SCIP_THREADPOOL* _threadpool = NULL;
_Thread_local int _threadnumber; /*lint !e129*/
/** A job added to the queue */
struct SCIP_Job
{
int jobid; /**< id to identify jobs from a common process */
struct SCIP_Job* nextjob; /**< pointer to the next job in the queue */
SCIP_RETCODE (*jobfunc)(void* args);/**< pointer to the job function */
void* args; /**< pointer to the function arguments */
SCIP_RETCODE retcode; /**< return code of the job */
};
/** the thread pool job queue */
struct SCIP_JobQueue
{
SCIP_JOB* firstjob; /**< pointer to the first job in the queue */
SCIP_JOB* lastjob; /**< pointer to the last job in the queue */
int njobs; /**< number of jobs in the queue */
};
typedef struct SCIP_JobQueue SCIP_JOBQUEUE;
/** The thread pool */
struct SCIP_ThreadPool
{
/* Pool Characteristics */
int nthreads; /**< number of threads in the pool */
int queuesize; /**< the total number of items to enter the queue */
/* Current pool state */
thrd_t* threads; /**< the threads included in the pool */
SCIP_JOBQUEUE* jobqueue; /**< the job queue */
SCIP_JOBQUEUE* currentjobs; /**< the jobs currently being processed on a thread;
* only a single job is allowed per thread. */
SCIP_JOBQUEUE* finishedjobs; /**< finished jobs that are not yet collected */
int currworkingthreads; /**< the threads currently processing jobs */
SCIP_Bool blockwhenfull; /**< indicates that the queue can only be as large as nthreads */
int currentid; /**< current job id */
/* Control indicators */
SCIP_Bool shutdown; /**< indicates whether the pool needs to be shut down */
SCIP_Bool queueopen; /**< indicates whether the queue is open */
/* mutex and locks for the thread pool */
mtx_t poollock; /**< mutex to allow read and write of the pool features */
cnd_t queuenotempty; /**< condition to broadcast the queue has jobs */
cnd_t queuenotfull; /**< condition to broadcast the queue is not full */
cnd_t queueempty; /**< condition to broadcast that the queue is empty */
cnd_t jobfinished; /**< condition to broadcast that a job has been finished */
};
/** this function controls the execution of each of the threads */
static
SCIP_RETCODE threadPoolThreadRetcode(
void* threadnum /**< thread number is passed in as argument stored inside a void pointer */
)
{
SCIP_JOB* newjob;
SCIP_JOB* prevjob;
SCIP_JOB* currjob;
_threadnumber = (int)(uintptr_t) threadnum;
/* Increase the number of active threads */
SCIP_CALL( SCIPtnyAcquireLock(&(_threadpool->poollock)) );
_threadpool->currworkingthreads += 1;
SCIP_CALL( SCIPtnyReleaseLock(&(_threadpool->poollock)) );
/* this is an endless loop that runs until the thrd_exit function is called */
while( TRUE ) /*lint !e716*/
{
SCIP_CALL( SCIPtnyAcquireLock(&(_threadpool->poollock)) );
/* the queue is empty but the shutdown command has not been given */
while( _threadpool->jobqueue->njobs == 0 && !_threadpool->shutdown )
{
SCIP_CALL( SCIPtnyWaitCondition(&(_threadpool->queuenotempty), &(_threadpool->poollock)) );
}
/* if the shutdown command has been given, then exit the thread */
if( _threadpool->shutdown )
{
/* Decrease the thread count when execution of job queue has completed */
_threadpool->currworkingthreads -= 1;
SCIP_CALL( SCIPtnyReleaseLock(&(_threadpool->poollock)) );
thrd_exit((int)SCIP_OKAY);
}
/* getting the next job in the queue */
newjob = _threadpool->jobqueue->firstjob;
_threadpool->jobqueue->njobs--; /* decreasing the number of jobs in the queue */
if( _threadpool->jobqueue->njobs == 0 )
{
_threadpool->jobqueue->firstjob = NULL;
_threadpool->jobqueue->lastjob = NULL;
}
else
_threadpool->jobqueue->firstjob = newjob->nextjob; /* updating the queue */
/* if we want to wait when the queue is full, then we broadcast that the queue can now take new jobs */
if( _threadpool->blockwhenfull &&
_threadpool->jobqueue->njobs == _threadpool->queuesize - 1 )
{
SCIP_CALL( SCIPtnyBroadcastCondition(&(_threadpool->queuenotfull)) );
}
/* indicating that the queue is empty */
if( _threadpool->jobqueue->njobs == 0 )
{
SCIP_CALL( SCIPtnyBroadcastCondition(&(_threadpool->queueempty)) );
}
/* updating the current job list */
if( _threadpool->currentjobs->njobs == 0 )
{
_threadpool->currentjobs->firstjob = newjob;
_threadpool->currentjobs->lastjob = newjob;
}
else
{
_threadpool->currentjobs->lastjob->nextjob = newjob;
_threadpool->currentjobs->lastjob = newjob;
}
_threadpool->currentjobs->njobs++;
SCIP_CALL( SCIPtnyReleaseLock(&(_threadpool->poollock)) );
/* setting the job to run on this thread */
newjob->retcode = (*(newjob->jobfunc))(newjob->args);
/* setting the current job on this thread to NULL */
SCIP_CALL( SCIPtnyAcquireLock(&(_threadpool->poollock)) );
/* finding the location of the processed job in the currentjobs queue */
currjob = _threadpool->currentjobs->firstjob;
prevjob = NULL;
while( currjob != newjob )
{
prevjob = currjob;
currjob = prevjob->nextjob;
}
/* removing the processed job from current jobs list */
if( currjob == _threadpool->currentjobs->firstjob )
_threadpool->currentjobs->firstjob = currjob->nextjob;
else
prevjob->nextjob = currjob->nextjob; /*lint !e794*/
if( currjob == _threadpool->currentjobs->lastjob )
_threadpool->currentjobs->lastjob = prevjob;
_threadpool->currentjobs->njobs--;
/* updating the finished job list */
if( _threadpool->finishedjobs->njobs == 0 )
{
_threadpool->finishedjobs->firstjob = newjob;
_threadpool->finishedjobs->lastjob = newjob;
}
else
{
_threadpool->finishedjobs->lastjob->nextjob = newjob;
_threadpool->finishedjobs->lastjob = newjob;
}
_threadpool->finishedjobs->njobs++;
/* signalling that a job has been finished */
SCIP_CALL( SCIPtnyBroadcastCondition(&(_threadpool)->jobfinished) );
SCIP_CALL( SCIPtnyReleaseLock(&(_threadpool->poollock)) );
}
}
/** this function controls the execution of each of the threads */
static
int threadPoolThread(
void* threadnum /**< thread number is passed in as argument stored inside a void pointer */
)
{
return (int) threadPoolThreadRetcode(threadnum);
}
/** creates a threadpool */
static
SCIP_RETCODE createThreadPool(
SCIP_THREADPOOL** thrdpool, /**< pointer to store threadpool */
int nthreads, /**< number of threads in the threadpool */
int qsize, /**< maximum size of the jobqueue */
SCIP_Bool blockwhenfull /**< should the jobqueue block if it is full */
)
{
uintptr_t i;
assert(nthreads >= 0);
assert(qsize >= 0);
/* @todo think about the correct memory here */
SCIP_ALLOC( BMSallocMemory(thrdpool) );
(*thrdpool)->currentid = 0;
(*thrdpool)->queuesize = qsize;
(*thrdpool)->nthreads = nthreads;
(*thrdpool)->blockwhenfull = blockwhenfull;
(*thrdpool)->shutdown = FALSE;
(*thrdpool)->queueopen = TRUE;
/* allocating memory for the job queue */
SCIP_ALLOC( BMSallocMemory(&(*thrdpool)->jobqueue) );
(*thrdpool)->jobqueue->firstjob = NULL;
(*thrdpool)->jobqueue->lastjob = NULL;
(*thrdpool)->jobqueue->njobs = 0;
/* allocating memory for the job queue */
SCIP_ALLOC( BMSallocMemory(&(*thrdpool)->currentjobs) );
(*thrdpool)->currentjobs->firstjob = NULL;
(*thrdpool)->currentjobs->lastjob = NULL;
(*thrdpool)->currentjobs->njobs = 0;
/* allocating memory for the job queue */
SCIP_ALLOC( BMSallocMemory(&(*thrdpool)->finishedjobs) );
(*thrdpool)->finishedjobs->firstjob = NULL;
(*thrdpool)->finishedjobs->lastjob = NULL;
(*thrdpool)->finishedjobs->njobs = 0;
/* initialising the mutex */
SCIP_CALL( SCIPtnyInitLock(&(*thrdpool)->poollock) ); /*lint !e2482*/
/* initialising the conditions */
SCIP_CALL( SCIPtnyInitCondition(&(*thrdpool)->queuenotempty) );
SCIP_CALL( SCIPtnyInitCondition(&(*thrdpool)->queuenotfull) );
SCIP_CALL( SCIPtnyInitCondition(&(*thrdpool)->queueempty) );
SCIP_CALL( SCIPtnyInitCondition(&(*thrdpool)->jobfinished) );
/* creating the threads */
(*thrdpool)->currworkingthreads = 0;
/* allocating memory for the threads */
SCIP_ALLOC( BMSallocMemoryArray(&((*thrdpool)->threads), nthreads) );
/* create the threads */
for( i = 0; i < (unsigned)nthreads; i++ )
{
if( thrd_create(&((*thrdpool)->threads[i]), threadPoolThread, (void*)i) != thrd_success )
return SCIP_ERROR;
}
_threadnumber = nthreads;
/* halt while all threads are not active TODO: is synchronization required here ? */
/*TODO: this caused a deadlock, is it important to wait for all threads to start?
* while( (*thrdpool)->currworkingthreads != nthreads )
{}*/
return SCIP_OKAY;
}
/** adding a job to the job queue.
*
* This gives some more flexibility in the handling of new jobs.
* This function needs to be called from within a mutex.
*/
static
void jobQueueAddJob(
SCIP_THREADPOOL* threadpool, /**< pointer to store threadpool */
SCIP_JOB* newjob /**< pointer to new job */
)
{
/* @todo we want to work out what to do with a full job queue. Is there a problem if the limit is hit? */
/* @note it is important to have a queuesize. This will stop the code submitting infinitely many jobs. */
assert(threadpool->jobqueue->njobs < threadpool->queuesize);
newjob->nextjob = NULL;
/* checking the status of the job queue */
if( threadpool->jobqueue->njobs == 0 )
{
threadpool->jobqueue->firstjob = newjob;
threadpool->jobqueue->lastjob = newjob;
}
else /* it is assumed that the jobqueue is not full */
{
threadpool->jobqueue->lastjob->nextjob = newjob;
threadpool->jobqueue->lastjob = newjob;
}
/* signalling to all threads that the queue has jobs using the signal instead of broadcast because only one thread
* should be awakened */
SCIP_CALL_ABORT( SCIPtnySignalCondition(&(threadpool->queuenotempty)) );
threadpool->jobqueue->njobs++;
}
/** adds a job to the threadpool */
static
SCIP_RETCODE threadPoolAddWork(
SCIP_JOB* newjob, /**< job to add to threadpool */
SCIP_SUBMITSTATUS* status /**< pointer to store the job's submit status */
)
{
assert(newjob != NULL);
assert(_threadpool != NULL);
SCIP_CALL( SCIPtnyAcquireLock(&(_threadpool->poollock)) );
/* if the queue is full and we are blocking, then return an error. */
if( _threadpool->jobqueue->njobs == _threadpool->queuesize && _threadpool->blockwhenfull )
{
SCIP_CALL( SCIPtnyReleaseLock(&(_threadpool->poollock)) );
*status = SCIP_SUBMIT_QUEUEFULL;
return SCIP_OKAY;
}
/* Wait until the job queue is not full. If the queue is closed or the thread pool is shut down, then stop waiting. */
/* @todo this needs to be checked. It is possible that a job can be submitted and then the queue is closed or the
* thread pool is shut down. Need to work out the best way to handle this. */
while( _threadpool->jobqueue->njobs == _threadpool->queuesize && !(_threadpool->shutdown || !_threadpool->queueopen) )
{
SCIP_CALL( SCIPtnyWaitCondition(&(_threadpool->queuenotfull), &(_threadpool->poollock)) );
}
/* if the thread pool is shut down or the queue is closed, then we need to leave the job submission */
if( !_threadpool->queueopen )
{
SCIP_CALL( SCIPtnyReleaseLock(&(_threadpool->poollock)) );
*status = SCIP_SUBMIT_QUEUECLOSED;
return SCIP_OKAY;
}
else if( _threadpool->shutdown )
{
SCIP_CALL( SCIPtnyReleaseLock(&(_threadpool->poollock)) );
*status = SCIP_SUBMIT_SHUTDOWN;
return SCIP_OKAY;
}
/* creating the job for submission */
newjob->nextjob = NULL;
/* adding the job to the queue */
/* this can only happen if the queue is not full */
assert(_threadpool->jobqueue->njobs != _threadpool->queuesize);
jobQueueAddJob(_threadpool, newjob);
SCIP_CALL( SCIPtnyReleaseLock(&(_threadpool->poollock)) );
*status = SCIP_SUBMIT_SUCCESS;
return SCIP_OKAY;
}
/** frees the jobqueue of the threadpool */
static
void freeJobQueue(
SCIP_THREADPOOL* thrdpool /**< pointer to thread pool */
)
{
SCIP_JOB* currjob;
assert(!thrdpool->queueopen);
assert(thrdpool->shutdown);
/* iterating through all jobs until all have been freed */
while( thrdpool->jobqueue->firstjob != NULL )
{
currjob = thrdpool->jobqueue->firstjob->nextjob;
thrdpool->jobqueue->firstjob = thrdpool->jobqueue->firstjob->nextjob;
BMSfreeMemory(&currjob);
}
assert(thrdpool->jobqueue->firstjob == NULL);
assert(thrdpool->jobqueue->lastjob == NULL);
BMSfreeMemory(&thrdpool->jobqueue);
}
/** free the thread pool */
static
SCIP_RETCODE freeThreadPool(
SCIP_THREADPOOL** thrdpool, /**< pointer to thread pool */
SCIP_Bool finishjobs, /**< currently unused */
SCIP_Bool completequeue /**< Wait until the queue has complete? */
)
{
int i;
SCIP_RETCODE retcode;
/*TODO remove argument? */
SCIP_UNUSED( finishjobs );
SCIP_CALL( SCIPtnyAcquireLock(&((*thrdpool)->poollock)) );
/* if the shutdown is already in progress, then we don't need to complete this function */
if( !(*thrdpool)->queueopen || (*thrdpool)->shutdown )
{
SCIP_CALL( SCIPtnyReleaseLock(&((*thrdpool)->poollock)) );
return SCIP_OKAY;
}
/* indicating that the job queue is now closed for new jobs */
(*thrdpool)->queueopen = FALSE;
/* if the jobs in the queue should be completed, then we wait until the queueempty condition is set */
if( completequeue )
{
while( (*thrdpool)->jobqueue->njobs > 0 )
{
SCIP_CALL( SCIPtnyWaitCondition(&((*thrdpool)->queueempty), &((*thrdpool)->poollock)) );
}
}
/* indicating that the tpi has commenced the shutdown process */
(*thrdpool)->shutdown = TRUE;
SCIP_CALL( SCIPtnyReleaseLock(&((*thrdpool)->poollock)) );
/* waking up all threads so that they can check the shutdown condition;
* this requires that the conditions queuenotempty and queuenotfull is broadcast
*/
SCIP_CALL( SCIPtnyBroadcastCondition(&((*thrdpool)->queuenotempty)) );
SCIP_CALL( SCIPtnyBroadcastCondition(&((*thrdpool)->queuenotfull)) );
retcode = SCIP_OKAY;
/* calling a join to ensure that all worker finish before the thread pool is closed */
for( i = 0; i < (*thrdpool)->nthreads; i++ )
{
int thrdretcode;
if( thrd_join((*thrdpool)->threads[i], &thrdretcode) != thrd_success )
retcode = (SCIP_RETCODE) MIN((int)SCIP_ERROR, (int)retcode);
else
retcode = (SCIP_RETCODE) MIN(thrdretcode, (int)retcode);
}
/* freeing memory and data structures */
BMSfreeMemoryArray(&(*thrdpool)->threads);
/* Freeing the current jobs list. This assumes that all jobs complete before the tpi is closed. */
assert((*thrdpool)->currentjobs->njobs == 0);
BMSfreeMemory(&(*thrdpool)->currentjobs);
assert((*thrdpool)->finishedjobs->njobs == 0);
BMSfreeMemory(&(*thrdpool)->finishedjobs);
freeJobQueue(*thrdpool);
/* destroying the conditions */
SCIPtnyDestroyCondition(&(*thrdpool)->jobfinished);
SCIPtnyDestroyCondition(&(*thrdpool)->queueempty);
SCIPtnyDestroyCondition(&(*thrdpool)->queuenotfull);
SCIPtnyDestroyCondition(&(*thrdpool)->queuenotempty);
/* destroying the mutex */
SCIPtnyDestroyLock(&(*thrdpool)->poollock);
BMSfreeMemory(thrdpool);
return retcode;
}
/* checking a job queue */
static
SCIP_JOBSTATUS checkJobQueue(
SCIP_JOBQUEUE* jobqueue, /**< pointer to the job queue */
int jobid /**< id of job to check */
)
{
SCIP_JOB* currjob = jobqueue->firstjob;
/* checking the job ids */
if( currjob != NULL )
{
while( currjob != jobqueue->lastjob )
{
if( currjob->jobid == jobid )
return SCIP_JOB_INQUEUE;
currjob = currjob->nextjob;
}
if( currjob->jobid == jobid )
return SCIP_JOB_INQUEUE;
}
return SCIP_JOB_DOESNOTEXIST;
}
/** returns whether the job id is running */
static
SCIP_Bool isJobRunning(
SCIP_JOBQUEUE* currentjobs, /**< queue of current jobs */
int jobid /**< id of job to check */
)
{
if( checkJobQueue(currentjobs, jobid) == SCIP_JOB_INQUEUE )
return TRUE;
else
return FALSE;
}
/** returns the number of threads */
int SCIPtpiGetNumThreads(
void
)
{
return _threadpool->nthreads;
}
/** initializes tpi */
SCIP_RETCODE SCIPtpiInit(
int nthreads, /**< the number of threads to be used */
int queuesize, /**< the size of the queue */
SCIP_Bool blockwhenfull /**< should the queue block when full */
)
{
assert(_threadpool == NULL);
SCIP_CALL( createThreadPool(&_threadpool, nthreads, queuesize, blockwhenfull) );
return SCIP_OKAY;
}
/** deinitializes tpi */
SCIP_RETCODE SCIPtpiExit(
void
)
{
assert(_threadpool != NULL);
SCIP_CALL( freeThreadPool(&_threadpool, TRUE, TRUE) );
return SCIP_OKAY;
}
/** creates a job for parallel processing */
SCIP_RETCODE SCIPtpiCreateJob(
SCIP_JOB** job, /**< pointer to the job that will be created */
int jobid, /**< the id for the current job */
SCIP_RETCODE (*jobfunc)(void* args),/**< pointer to the job function */
void* jobarg /**< the job's argument */
)
{
SCIP_ALLOC( BMSallocMemory(job) );
(*job)->jobid = jobid;
(*job)->jobfunc = jobfunc;
(*job)->args = jobarg;
(*job)->nextjob = NULL;
return SCIP_OKAY;
}
/** get a new job id for the new set of submitted jobs */
int SCIPtpiGetNewJobID(
void
)
{
int id;
assert(_threadpool != NULL);
SCIP_CALL_ABORT( SCIPtnyAcquireLock(&_threadpool->poollock) );
id = ++_threadpool->currentid;
SCIP_CALL_ABORT( SCIPtnyReleaseLock(&_threadpool->poollock) );
return id;
}
/** submit a job for parallel processing; the return value is a globally defined status */
SCIP_RETCODE SCIPtpiSubmitJob(
SCIP_JOB* job, /**< pointer to the job to be submitted */
SCIP_SUBMITSTATUS* status /**< pointer to store the job's submit status */
)
{
assert(job != NULL);
/* the job id must be set before submitting the job. The submitter controls whether a new id is required. */
assert(job->jobid == _threadpool->currentid);
SCIP_CALL( threadPoolAddWork(job, status) );
return SCIP_OKAY;
}
/** blocks until all jobs of the given jobid have finished
* and then returns the smallest SCIP_RETCODE of all the jobs
*/
SCIP_RETCODE SCIPtpiCollectJobs(
int jobid /**< the jobid of the jobs to wait for */
)
{
SCIP_RETCODE retcode;
SCIP_JOB* currjob;
SCIP_JOB* prevjob;
SCIP_CALL( SCIPtnyAcquireLock(&(_threadpool->poollock)) );
while( isJobRunning(_threadpool->currentjobs, jobid) || isJobRunning(_threadpool->jobqueue, jobid) )
{
SCIP_CALL( SCIPtnyWaitCondition(&_threadpool->jobfinished, &_threadpool->poollock) );
}
/* finding the location of the processed job in the currentjobs queue */
retcode = SCIP_OKAY;
currjob = _threadpool->finishedjobs->firstjob;
prevjob = NULL;
while( currjob )
{
if( currjob->jobid == jobid )
{
SCIP_JOB* nextjob;
/* if the job has the right jobid collect its retcode,
* remove it from the finished job list, and free it
*/
retcode = MIN(retcode, currjob->retcode);
/* removing the finished job from finished jobs list */
if( currjob == _threadpool->finishedjobs->firstjob )
{
_threadpool->finishedjobs->firstjob = currjob->nextjob;
}
else
{
assert(prevjob != NULL);
prevjob->nextjob = currjob->nextjob;
}
if( currjob == _threadpool->finishedjobs->lastjob )
_threadpool->finishedjobs->lastjob = prevjob;
_threadpool->finishedjobs->njobs--;
/* update currjob and free finished job; prevjob stays the same */
nextjob = currjob->nextjob;
BMSfreeMemory(&currjob);
currjob = nextjob;
}
else
{
/* otherwise leave job untouched */
prevjob = currjob;
currjob = prevjob->nextjob;
}
}
SCIP_CALL( SCIPtnyReleaseLock(&_threadpool->poollock) );
return retcode;
}
/*
* locks
*/
/** initializes the given lock */
SCIP_RETCODE SCIPtpiInitLock(
SCIP_LOCK** lock /**< the lock */
)
{
assert(lock != NULL);
SCIP_ALLOC( BMSallocMemory(lock) );
if( mtx_init(&(*lock)->lock, mtx_plain) == thrd_success )
return SCIP_OKAY;
else
{
BMSfreeMemory(lock);
return SCIP_ERROR;
}
}
/** destroys the given lock */
void SCIPtpiDestroyLock(
SCIP_LOCK** lock /**< the lock */
)
{
assert(lock != NULL);
mtx_destroy(&(*lock)->lock);
BMSfreeMemory(lock);
}
/** acquires the given lock */
SCIP_RETCODE SCIPtpiAcquireLock(
SCIP_LOCK* lock /**< the lock */
)
{
if( mtx_lock(&lock->lock) == thrd_success )
return SCIP_OKAY;
return SCIP_ERROR;
}
/** releases the given lock */
SCIP_RETCODE SCIPtpiReleaseLock(
SCIP_LOCK* lock /**< the lock */
)
{
if( mtx_unlock(&lock->lock) == thrd_success )
return SCIP_OKAY;
return SCIP_ERROR;
}
/*
* conditions
*/
/** initializes the given condition variable */
SCIP_RETCODE SCIPtpiInitCondition(
SCIP_CONDITION** condition /**< condition to be created and initialized */
)
{
assert(condition != NULL);
SCIP_ALLOC( BMSallocMemory(condition) );
if( cnd_init(&(*condition)->condition) == thrd_success )
return SCIP_OKAY;
return SCIP_ERROR;
}
/** destroys the given condition variable */
void SCIPtpiDestroyCondition(
SCIP_CONDITION** condition /**< condition to be destroyed and freed */
)
{
cnd_destroy(&(*condition)->condition);
BMSfreeMemory(condition);
}
/** signals one waiting thread */
SCIP_RETCODE SCIPtpiSignalCondition(
SCIP_CONDITION* condition /**< the condition variable to signal */
)
{
if( cnd_signal(&condition->condition) == thrd_success )
return SCIP_OKAY;
return SCIP_ERROR;
}
/** signals all waiting threads */
SCIP_EXPORT
SCIP_RETCODE SCIPtpiBroadcastCondition(
SCIP_CONDITION* condition /**< the condition variable to broadcast */
)
{
if( cnd_broadcast(&condition->condition) == thrd_success )
return SCIP_OKAY;
return SCIP_ERROR;
}
/** waits on a condition variable. The given lock must be held by the caller and will
* be held when this function returns.
*/
SCIP_RETCODE SCIPtpiWaitCondition(
SCIP_CONDITION* condition, /**< the condition variable to wait on */
SCIP_LOCK* lock /**< the lock that is held by the caller */
)
{
if( cnd_wait(&condition->condition, &lock->lock) == thrd_success )
return SCIP_OKAY;
return SCIP_ERROR;
}
/** returns the thread number */
int SCIPtpiGetThreadNum(
void
)
{
return _threadnumber;
}