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
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
|
/*
* Copyright (C) 2016, 2017 "IoT.bzh"
* Author José Bollo <jose.bollo@iot.bzh>
*
* 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.
*/
#define _GNU_SOURCE
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>
#include <signal.h>
#include <time.h>
#include <sys/syscall.h>
#include <pthread.h>
#include <errno.h>
#include <assert.h>
#include <sys/eventfd.h>
#include <systemd/sd-event.h>
#ifndef NO_JOBS_WATCHDOG
#include <systemd/sd-daemon.h>
#endif
#include "jobs.h"
#include "sig-monitor.h"
#include "verbose.h"
#if 0
#define _alert_ "do you really want to remove monitoring?"
#define sig_monitor_init_timeouts() ((void)0)
#define sig_monitor_clean_timeouts() ((void)0)
#define sig_monitor(to,cb,arg) (cb(0,arg))
#endif
#define EVENT_TIMEOUT_TOP ((uint64_t)-1)
#define EVENT_TIMEOUT_CHILD ((uint64_t)10000)
/** Internal shortcut for callback */
typedef void (*job_cb_t)(int, void*);
/** Description of a pending job */
struct job
{
struct job *next; /**< link to the next job enqueued */
const void *group; /**< group of the request */
job_cb_t callback; /**< processing callback */
void *arg; /**< argument */
int timeout; /**< timeout in second for processing the request */
unsigned blocked: 1; /**< is an other request blocking this one ? */
unsigned dropped: 1; /**< is removed ? */
};
/** Description of handled event loops */
struct evloop
{
unsigned state; /**< encoded state */
int efd; /**< event notification */
struct sd_event *sdev; /**< the systemd event loop */
pthread_cond_t cond; /**< condition */
};
#define EVLOOP_STATE_WAIT 1U
#define EVLOOP_STATE_RUN 2U
#define EVLOOP_STATE_LOCK 4U
/** Description of threads */
struct thread
{
struct thread *next; /**< next thread of the list */
struct thread *upper; /**< upper same thread */
struct job *job; /**< currently processed job */
pthread_t tid; /**< the thread id */
unsigned stop: 1; /**< stop requested */
unsigned waits: 1; /**< is waiting? */
};
/**
* Description of synchonous callback
*/
struct sync
{
struct thread thread; /**< thread loop data */
union {
void (*callback)(int, void*); /**< the synchronous callback */
void (*enter)(int signum, void *closure, struct jobloop *jobloop);
/**< the entering synchronous routine */
};
void *arg; /**< the argument of the callback */
};
/* synchronisation of threads */
static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
/* count allowed, started and running threads */
static int allowed = 0; /** allowed count of threads */
static int started = 0; /** started count of threads */
static int running = 0; /** running count of threads */
static int remains = 0; /** allowed count of waiting jobs */
/* list of threads */
static struct thread *threads;
static _Thread_local struct thread *current_thread;
static _Thread_local struct evloop *current_evloop;
/* queue of pending jobs */
static struct job *first_job;
static struct job *free_jobs;
/* event loop */
static struct evloop evloop[1];
/**
* Create a new job with the given parameters
* @param group the group of the job
* @param timeout the timeout of the job (0 if none)
* @param callback the function that achieves the job
* @param arg the argument of the callback
* @return the created job unblock or NULL when no more memory
*/
static struct job *job_create(
const void *group,
int timeout,
job_cb_t callback,
void *arg)
{
struct job *job;
/* try recyle existing job */
job = free_jobs;
if (job)
free_jobs = job->next;
else {
/* allocation without blocking */
pthread_mutex_unlock(&mutex);
job = malloc(sizeof *job);
pthread_mutex_lock(&mutex);
if (!job) {
errno = -ENOMEM;
goto end;
}
}
/* initialises the job */
job->group = group;
job->timeout = timeout;
job->callback = callback;
job->arg = arg;
job->blocked = 0;
job->dropped = 0;
end:
return job;
}
/**
* Adds 'job' at the end of the list of jobs, marking it
* as blocked if an other job with the same group is pending.
* @param job the job to add
*/
static void job_add(struct job *job)
{
const void *group;
struct job *ijob, **pjob;
/* prepare to add */
group = job->group;
job->next = NULL;
/* search end and blockers */
pjob = &first_job;
ijob = first_job;
while (ijob) {
if (group && ijob->group == group)
job->blocked = 1;
pjob = &ijob->next;
ijob = ijob->next;
}
/* queue the jobs */
*pjob = job;
}
/**
* Get the next job to process or NULL if none.
* @return the first job that isn't blocked or NULL
*/
static inline struct job *job_get()
{
struct job *job = first_job;
while (job && job->blocked)
job = job->next;
return job;
}
/**
* Releases the processed 'job': removes it
* from the list of jobs and unblock the first
* pending job of the same group if any.
* @param job the job to release
*/
static inline void job_release(struct job *job)
{
struct job *ijob, **pjob;
const void *group;
/* first unqueue the job */
pjob = &first_job;
ijob = first_job;
while (ijob != job) {
pjob = &ijob->next;
ijob = ijob->next;
}
*pjob = job->next;
/* then unblock jobs of the same group */
group = job->group;
if (group) {
ijob = job->next;
while (ijob && ijob->group != group)
ijob = ijob->next;
if (ijob)
ijob->blocked = 0;
}
/* recycle the job */
job->next = free_jobs;
free_jobs = job;
}
/**
* Monitored cancel callback for a job.
* This function is called by the monitor
* to cancel the job when the safe environment
* is set.
* @param signum 0 on normal flow or the number
* of the signal that interrupted the normal
* flow, isn't used
* @param arg the job to run
*/
static void job_cancel(int signum, void *arg)
{
struct job *job = arg;
job->callback(SIGABRT, job->arg);
}
/**
* Monitored normal callback for events.
* This function is called by the monitor
* to run the event loop when the safe environment
* is set.
* @param signum 0 on normal flow or the number
* of the signal that interrupted the normal
* flow
* @param arg the events to run
*/
static void evloop_run(int signum, void *arg)
{
int rc;
struct sd_event *se;
struct evloop *el = arg;
if (!signum) {
se = el->sdev;
rc = sd_event_prepare(se);
if (rc < 0) {
errno = -rc;
ERROR("sd_event_prepare returned an error (state: %d): %m", sd_event_get_state(se));
} else {
if (rc == 0) {
rc = sd_event_wait(se, (uint64_t)(int64_t)-1);
if (rc < 0) {
errno = -rc;
ERROR("sd_event_wait returned an error (state: %d): %m", sd_event_get_state(se));
}
}
__atomic_and_fetch(&el->state, ~(EVLOOP_STATE_WAIT), __ATOMIC_RELAXED);
if (rc > 0) {
rc = sd_event_dispatch(se);
if (rc < 0) {
errno = -rc;
ERROR("sd_event_dispatch returned an error (state: %d): %m", sd_event_get_state(se));
}
}
}
}
__atomic_and_fetch(&el->state, ~(EVLOOP_STATE_WAIT|EVLOOP_STATE_RUN), __ATOMIC_RELAXED);
}
/**
* Main processing loop of threads processing jobs.
* The loop must be called with the mutex locked
* and it returns with the mutex locked.
* @param me the description of the thread to use
* TODO: how are timeout handled when reentering?
*/
static void thread_run(volatile struct thread *me)
{
struct thread **prv;
struct job *job;
struct evloop *el;
/* initialize description of itself and link it in the list */
me->tid = pthread_self();
me->stop = 0;
me->waits = 0;
me->upper = current_thread;
if (!current_thread) {
started++;
sig_monitor_init_timeouts();
}
me->next = threads;
threads = (struct thread*)me;
current_thread = (struct thread*)me;
/* loop until stopped */
while (!me->stop) {
/* release the event loop */
if (current_evloop) {
__atomic_sub_fetch(¤t_evloop->state, EVLOOP_STATE_LOCK, __ATOMIC_RELAXED);
current_evloop = NULL;
}
/* get a job */
job = job_get(first_job);
if (job) {
/* prepare running the job */
remains++; /* increases count of job that can wait */
job->blocked = 1; /* mark job as blocked */
me->job = job; /* record the job (only for terminate) */
/* run the job */
pthread_mutex_unlock(&mutex);
sig_monitor(job->timeout, job->callback, job->arg);
pthread_mutex_lock(&mutex);
/* release the run job */
job_release(job);
} else {
/* no job, check events */
el = &evloop[0];
if (el->sdev && !__atomic_load_n(&el->state, __ATOMIC_RELAXED)) {
/* run the events */
__atomic_store_n(&el->state, EVLOOP_STATE_LOCK|EVLOOP_STATE_RUN|EVLOOP_STATE_WAIT, __ATOMIC_RELAXED);
current_evloop = el;
pthread_mutex_unlock(&mutex);
sig_monitor(0, evloop_run, el);
pthread_mutex_lock(&mutex);
} else {
/* no job and not events */
running--;
if (!running)
ERROR("Entering job deep sleep! Check your bindings.");
me->waits = 1;
pthread_cond_wait(&cond, &mutex);
me->waits = 0;
running++;
}
}
}
/* release the event loop */
if (current_evloop) {
__atomic_sub_fetch(¤t_evloop->state, EVLOOP_STATE_LOCK, __ATOMIC_RELAXED);
current_evloop = NULL;
}
/* unlink the current thread and cleanup */
prv = &threads;
while (*prv != me)
prv = &(*prv)->next;
*prv = me->next;
current_thread = me->upper;
if (!current_thread) {
sig_monitor_clean_timeouts();
started--;
}
}
/**
* Entry point for created threads.
* @param data not used
* @return NULL
*/
static void *thread_main(void *data)
{
struct thread me;
pthread_mutex_lock(&mutex);
running++;
thread_run(&me);
running--;
pthread_mutex_unlock(&mutex);
return NULL;
}
/**
* Starts a new thread
* @return 0 in case of success or -1 in case of error
*/
static int start_one_thread()
{
pthread_t tid;
int rc;
rc = pthread_create(&tid, NULL, thread_main, NULL);
if (rc != 0) {
/* errno = rc; */
WARNING("not able to start thread: %m");
rc = -1;
}
return rc;
}
/**
* Queues a new asynchronous job represented by 'callback' and 'arg'
* for the 'group' and the 'timeout'.
* Jobs are queued FIFO and are possibly executed in parallel
* concurrently except for job of the same group that are
* executed sequentially in FIFO order.
* @param group The group of the job or NULL when no group.
* @param timeout The maximum execution time in seconds of the job
* or 0 for unlimited time.
* @param callback The function to execute for achieving the job.
* Its first parameter is either 0 on normal flow
* or the signal number that broke the normal flow.
* The remaining parameter is the parameter 'arg1'
* given here.
* @param arg The second argument for 'callback'
* @return 0 in case of success or -1 in case of error
*/
int jobs_queue(
const void *group,
int timeout,
void (*callback)(int, void*),
void *arg)
{
const char *info;
struct job *job;
int rc;
pthread_mutex_lock(&mutex);
/* allocates the job */
job = job_create(group, timeout, callback, arg);
if (!job) {
errno = ENOMEM;
info = "out of memory";
goto error;
}
/* check availability */
if (remains == 0) {
errno = EBUSY;
info = "too many jobs";
goto error2;
}
/* start a thread if needed */
if (running == started && started < allowed) {
/* all threads are busy and a new can be started */
rc = start_one_thread();
if (rc < 0 && started == 0) {
info = "can't start first thread";
goto error2;
}
}
/* queues the job */
remains--;
job_add(job);
/* signal an existing job */
pthread_cond_signal(&cond);
pthread_mutex_unlock(&mutex);
return 0;
error2:
job->next = free_jobs;
free_jobs = job;
error:
ERROR("can't process job with threads: %s, %m", info);
pthread_mutex_unlock(&mutex);
return -1;
}
/**
* Internal helper function for 'jobs_enter'.
* @see jobs_enter, jobs_leave
*/
static void enter_cb(int signum, void *closure)
{
struct sync *sync = closure;
sync->enter(signum, sync->arg, (void*)&sync->thread);
}
/**
* Internal helper function for 'jobs_call'.
* @see jobs_call
*/
static void call_cb(int signum, void *closure)
{
struct sync *sync = closure;
sync->callback(signum, sync->arg);
jobs_leave((void*)&sync->thread);
}
/**
* Internal helper for synchronous jobs. It enters
* a new thread loop for evaluating the given job
* as recorded by the couple 'sync_cb' and 'sync'.
* @see jobs_call, jobs_enter, jobs_leave
*/
static int do_sync(
const void *group,
int timeout,
void (*sync_cb)(int signum, void *closure),
struct sync *sync
)
{
struct job *job;
pthread_mutex_lock(&mutex);
/* allocates the job */
job = job_create(group, timeout, sync_cb, sync);
if (!job) {
ERROR("out of memory");
errno = ENOMEM;
pthread_mutex_unlock(&mutex);
return -1;
}
/* queues the job */
job_add(job);
/* run until stopped */
thread_run(&sync->thread);
pthread_mutex_unlock(&mutex);
return 0;
}
/**
* Enter a synchronisation point: activates the job given by 'callback'
* and 'closure' using 'group' and 'timeout' to control sequencing and
* execution time.
* @param group the group for sequencing jobs
* @param timeout the time in seconds allocated to the job
* @param callback the callback that will handle the job.
* it receives 3 parameters: 'signum' that will be 0
* on normal flow or the catched signal number in case
* of interrupted flow, the context 'closure' as given and
* a 'jobloop' reference that must be used when the job is
* terminated to unlock the current execution flow.
* @param arg the argument to the callback
* @return 0 on success or -1 in case of error
*/
int jobs_enter(
const void *group,
int timeout,
void (*callback)(int signum, void *closure, struct jobloop *jobloop),
void *closure
)
{
struct sync sync;
sync.enter = callback;
sync.arg = closure;
return do_sync(group, timeout, enter_cb, &sync);
}
/**
* Unlocks the execution flow designed by 'jobloop'.
* @param jobloop indication of the flow to unlock
* @return 0 in case of success of -1 on error
*/
int jobs_leave(struct jobloop *jobloop)
{
struct thread *t;
pthread_mutex_lock(&mutex);
t = threads;
while (t && t != (struct thread*)jobloop)
t = t->next;
if (!t) {
errno = EINVAL;
} else {
t->stop = 1;
if (t->waits)
pthread_cond_broadcast(&cond);
}
pthread_mutex_unlock(&mutex);
return -!t;
}
/**
* Calls synchronously the job represented by 'callback' and 'arg1'
* for the 'group' and the 'timeout' and waits for its completion.
* @param group The group of the job or NULL when no group.
* @param timeout The maximum execution time in seconds of the job
* or 0 for unlimited time.
* @param callback The function to execute for achieving the job.
* Its first parameter is either 0 on normal flow
* or the signal number that broke the normal flow.
* The remaining parameter is the parameter 'arg1'
* given here.
* @param arg The second argument for 'callback'
* @return 0 in case of success or -1 in case of error
*/
int jobs_call(
const void *group,
int timeout,
void (*callback)(int, void*),
void *arg)
{
struct sync sync;
sync.callback = callback;
sync.arg = arg;
return do_sync(group, timeout, call_cb, &sync);
}
/**
* Internal callback for evloop management.
* The effect of this function is hidden: it exits
* the waiting poll if any. Then it wakes up a thread
* awaiting the evloop using signal.
*/
static int on_evloop_efd(sd_event_source *s, int fd, uint32_t revents, void *userdata)
{
uint64_t x;
struct evloop *evloop = userdata;
read(evloop->efd, &x, sizeof x);
pthread_mutex_lock(&mutex);
pthread_cond_broadcast(&evloop->cond);
pthread_mutex_unlock(&mutex);
return 1;
}
/**
* Gets a sd_event item for the current thread.
* @return a sd_event or NULL in case of error
*/
static struct sd_event *get_sd_event_locked()
{
struct evloop *el;
uint64_t x;
int rc;
/* creates the evloop on need */
el = &evloop[0];
if (!el->sdev) {
/* start the creation */
el->state = 0;
/* creates the eventfd for waking up polls */
el->efd = eventfd(0, EFD_CLOEXEC);
if (el->efd < 0) {
ERROR("can't make eventfd for events");
goto error1;
}
/* create the systemd event loop */
rc = sd_event_new(&el->sdev);
if (rc < 0) {
ERROR("can't make new event loop");
goto error2;
}
/* put the eventfd in the event loop */
rc = sd_event_add_io(el->sdev, NULL, el->efd, EPOLLIN, on_evloop_efd, el);
if (rc < 0) {
ERROR("can't register eventfd");
sd_event_unref(el->sdev);
el->sdev = NULL;
error2:
close(el->efd);
error1:
return NULL;
}
}
/* attach the event loop to the current thread */
if (current_evloop != el) {
if (current_evloop)
__atomic_sub_fetch(¤t_evloop->state, EVLOOP_STATE_LOCK, __ATOMIC_RELAXED);
current_evloop = el;
__atomic_add_fetch(&el->state, EVLOOP_STATE_LOCK, __ATOMIC_RELAXED);
}
/* wait for a modifiable event loop */
while (__atomic_load_n(&el->state, __ATOMIC_RELAXED) & EVLOOP_STATE_WAIT) {
x = 1;
write(el->efd, &x, sizeof x);
pthread_cond_wait(&el->cond, &mutex);
}
return el->sdev;
}
/**
* Gets a sd_event item for the current thread.
* @return a sd_event or NULL in case of error
*/
struct sd_event *jobs_get_sd_event()
{
struct sd_event *result;
pthread_mutex_lock(&mutex);
result = get_sd_event_locked();
pthread_mutex_unlock(&mutex);
return result;
}
/**
* Enter the jobs processing loop.
* @param allowed_count Maximum count of thread for jobs including this one
* @param start_count Count of thread to start now, must be lower.
* @param waiter_count Maximum count of jobs that can be waiting.
* @param start The start routine to activate (can't be NULL)
* @return 0 in case of success or -1 in case of error.
*/
int jobs_start(int allowed_count, int start_count, int waiter_count, void (*start)(int signum))
{
int rc, launched;
struct thread me;
struct job *job;
assert(allowed_count >= 1);
assert(start_count >= 0);
assert(waiter_count > 0);
assert(start_count <= allowed_count);
rc = -1;
pthread_mutex_lock(&mutex);
/* check whether already running */
if (current_thread || allowed) {
ERROR("thread already started");
errno = EINVAL;
goto error;
}
/* start */
if (sig_monitor_init() < 0) {
ERROR("failed to initialise signal handlers");
goto error;
}
/* records the allowed count */
allowed = allowed_count;
started = 0;
running = 0;
remains = waiter_count;
#ifndef NO_JOBS_WATCHDOG
/* set the watchdog */
if (sd_watchdog_enabled(0, NULL))
sd_event_set_watchdog(get_sd_event_locked(), 1);
#endif
/* start at least one thread */
launched = 0;
while ((launched + 1) < start_count) {
if (start_one_thread() != 0) {
ERROR("Not all threads can be started");
goto error;
}
launched++;
}
/* queue the start job */
job = job_create(NULL, 0, (job_cb_t)start, NULL);
if (!job) {
ERROR("out of memory");
errno = ENOMEM;
goto error;
}
job_add(job);
remains--;
/* run until end */
thread_run(&me);
rc = 0;
error:
pthread_mutex_unlock(&mutex);
return rc;
}
/**
* Terminate all the threads and cancel all pending jobs.
*/
void jobs_terminate()
{
struct job *job, *head, *tail;
pthread_t me, *others;
struct thread *t;
int count;
/* how am i? */
me = pthread_self();
/* request all threads to stop */
pthread_mutex_lock(&mutex);
allowed = 0;
/* count the number of threads */
count = 0;
t = threads;
while (t) {
if (!t->upper && !pthread_equal(t->tid, me))
count++;
t = t->next;
}
/* fill the array of threads */
others = alloca(count * sizeof *others);
count = 0;
t = threads;
while (t) {
if (!t->upper && !pthread_equal(t->tid, me))
others[count++] = t->tid;
t = t->next;
}
/* stops the threads */
t = threads;
while (t) {
t->stop = 1;
t = t->next;
}
/* wait the threads */
pthread_cond_broadcast(&cond);
pthread_mutex_unlock(&mutex);
while (count)
pthread_join(others[--count], NULL);
pthread_mutex_lock(&mutex);
/* cancel pending jobs of other threads */
remains = 0;
head = first_job;
first_job = NULL;
tail = NULL;
while (head) {
/* unlink the job */
job = head;
head = job->next;
/* search if job is stacked for current */
t = current_thread;
while (t && t->job != job)
t = t->upper;
if (t) {
/* yes, relink it at end */
if (tail)
tail->next = job;
else
first_job = job;
tail = job;
job->next = NULL;
} else {
/* no cancel the job */
pthread_mutex_unlock(&mutex);
sig_monitor(0, job_cancel, job);
free(job);
pthread_mutex_lock(&mutex);
}
}
pthread_mutex_unlock(&mutex);
}
|