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1 /*
2  * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
3  * Copyright (c) 2006 David Xu <davidxu@freebsd.org>.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *      This product includes software developed by John Birrell.
17  * 4. Neither the name of the author nor the names of any co-contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * $FreeBSD$
34  */
35
36 #include "namespace.h"
37 #include <stdlib.h>
38 #include <errno.h>
39 #include <string.h>
40 #include <sys/param.h>
41 #include <sys/queue.h>
42 #include <pthread.h>
43 #include <pthread_np.h>
44 #include "un-namespace.h"
45
46 #include "thr_private.h"
47
48 #if defined(_PTHREADS_INVARIANTS)
49 #define MUTEX_INIT_LINK(m)              do {            \
50         (m)->m_qe.tqe_prev = NULL;                      \
51         (m)->m_qe.tqe_next = NULL;                      \
52 } while (0)
53 #define MUTEX_ASSERT_IS_OWNED(m)        do {            \
54         if (__predict_false((m)->m_qe.tqe_prev == NULL))\
55                 PANIC("mutex is not on list");          \
56 } while (0)
57 #define MUTEX_ASSERT_NOT_OWNED(m)       do {            \
58         if (__predict_false((m)->m_qe.tqe_prev != NULL ||       \
59             (m)->m_qe.tqe_next != NULL))        \
60                 PANIC("mutex is on list");              \
61 } while (0)
62 #else
63 #define MUTEX_INIT_LINK(m)
64 #define MUTEX_ASSERT_IS_OWNED(m)
65 #define MUTEX_ASSERT_NOT_OWNED(m)
66 #endif
67
68 /*
69  * For adaptive mutexes, how many times to spin doing trylock2
70  * before entering the kernel to block
71  */
72 #define MUTEX_ADAPTIVE_SPINS    2000
73
74 /*
75  * Prototypes
76  */
77 int     __pthread_mutex_init(pthread_mutex_t *mutex,
78                 const pthread_mutexattr_t *mutex_attr);
79 int     __pthread_mutex_trylock(pthread_mutex_t *mutex);
80 int     __pthread_mutex_lock(pthread_mutex_t *mutex);
81 int     __pthread_mutex_timedlock(pthread_mutex_t *mutex,
82                 const struct timespec *abstime);
83 int     _pthread_mutex_init_calloc_cb(pthread_mutex_t *mutex,
84                 void *(calloc_cb)(size_t, size_t));
85 int     _pthread_mutex_getspinloops_np(pthread_mutex_t *mutex, int *count);
86 int     _pthread_mutex_setspinloops_np(pthread_mutex_t *mutex, int count);
87 int     __pthread_mutex_setspinloops_np(pthread_mutex_t *mutex, int count);
88 int     _pthread_mutex_setyieldloops_np(pthread_mutex_t *mutex, int count);
89 int     _pthread_mutex_getyieldloops_np(pthread_mutex_t *mutex, int *count);
90 int     __pthread_mutex_setyieldloops_np(pthread_mutex_t *mutex, int count);
91
92 static int      mutex_self_trylock(pthread_mutex_t);
93 static int      mutex_self_lock(pthread_mutex_t,
94                                 const struct timespec *abstime);
95 static int      mutex_unlock_common(struct pthread_mutex *, int);
96 static int      mutex_lock_sleep(struct pthread *, pthread_mutex_t,
97                                 const struct timespec *);
98
99 __weak_reference(__pthread_mutex_init, pthread_mutex_init);
100 __strong_reference(__pthread_mutex_init, _pthread_mutex_init);
101 __weak_reference(__pthread_mutex_lock, pthread_mutex_lock);
102 __strong_reference(__pthread_mutex_lock, _pthread_mutex_lock);
103 __weak_reference(__pthread_mutex_timedlock, pthread_mutex_timedlock);
104 __strong_reference(__pthread_mutex_timedlock, _pthread_mutex_timedlock);
105 __weak_reference(__pthread_mutex_trylock, pthread_mutex_trylock);
106 __strong_reference(__pthread_mutex_trylock, _pthread_mutex_trylock);
107
108 /* Single underscore versions provided for libc internal usage: */
109 /* No difference between libc and application usage of these: */
110 __weak_reference(_pthread_mutex_destroy, pthread_mutex_destroy);
111 __weak_reference(_pthread_mutex_unlock, pthread_mutex_unlock);
112
113 __weak_reference(_pthread_mutex_getprioceiling, pthread_mutex_getprioceiling);
114 __weak_reference(_pthread_mutex_setprioceiling, pthread_mutex_setprioceiling);
115
116 __weak_reference(__pthread_mutex_setspinloops_np, pthread_mutex_setspinloops_np);
117 __strong_reference(__pthread_mutex_setspinloops_np, _pthread_mutex_setspinloops_np);
118 __weak_reference(_pthread_mutex_getspinloops_np, pthread_mutex_getspinloops_np);
119
120 __weak_reference(__pthread_mutex_setyieldloops_np, pthread_mutex_setyieldloops_np);
121 __strong_reference(__pthread_mutex_setyieldloops_np, _pthread_mutex_setyieldloops_np);
122 __weak_reference(_pthread_mutex_getyieldloops_np, pthread_mutex_getyieldloops_np);
123 __weak_reference(_pthread_mutex_isowned_np, pthread_mutex_isowned_np);
124
125 static int
126 mutex_init(pthread_mutex_t *mutex,
127     const struct pthread_mutex_attr *mutex_attr,
128     void *(calloc_cb)(size_t, size_t))
129 {
130         const struct pthread_mutex_attr *attr;
131         struct pthread_mutex *pmutex;
132
133         if (mutex_attr == NULL) {
134                 attr = &_pthread_mutexattr_default;
135         } else {
136                 attr = mutex_attr;
137                 if (attr->m_type < PTHREAD_MUTEX_ERRORCHECK ||
138                     attr->m_type >= PTHREAD_MUTEX_TYPE_MAX)
139                         return (EINVAL);
140                 if (attr->m_protocol < PTHREAD_PRIO_NONE ||
141                     attr->m_protocol > PTHREAD_PRIO_PROTECT)
142                         return (EINVAL);
143         }
144         if ((pmutex = (pthread_mutex_t)
145                 calloc_cb(1, sizeof(struct pthread_mutex))) == NULL)
146                 return (ENOMEM);
147
148         pmutex->m_flags = attr->m_type;
149         pmutex->m_owner = NULL;
150         pmutex->m_count = 0;
151         pmutex->m_spinloops = 0;
152         pmutex->m_yieldloops = 0;
153         MUTEX_INIT_LINK(pmutex);
154         switch(attr->m_protocol) {
155         case PTHREAD_PRIO_NONE:
156                 pmutex->m_lock.m_owner = UMUTEX_UNOWNED;
157                 pmutex->m_lock.m_flags = 0;
158                 break;
159         case PTHREAD_PRIO_INHERIT:
160                 pmutex->m_lock.m_owner = UMUTEX_UNOWNED;
161                 pmutex->m_lock.m_flags = UMUTEX_PRIO_INHERIT;
162                 break;
163         case PTHREAD_PRIO_PROTECT:
164                 pmutex->m_lock.m_owner = UMUTEX_CONTESTED;
165                 pmutex->m_lock.m_flags = UMUTEX_PRIO_PROTECT;
166                 pmutex->m_lock.m_ceilings[0] = attr->m_ceiling;
167                 break;
168         }
169
170         if (PMUTEX_TYPE(pmutex->m_flags) == PTHREAD_MUTEX_ADAPTIVE_NP) {
171                 pmutex->m_spinloops =
172                     _thr_spinloops ? _thr_spinloops: MUTEX_ADAPTIVE_SPINS;
173                 pmutex->m_yieldloops = _thr_yieldloops;
174         }
175
176         *mutex = pmutex;
177         return (0);
178 }
179
180 static int
181 init_static(struct pthread *thread, pthread_mutex_t *mutex)
182 {
183         int ret;
184
185         THR_LOCK_ACQUIRE(thread, &_mutex_static_lock);
186
187         if (*mutex == THR_MUTEX_INITIALIZER)
188                 ret = mutex_init(mutex, &_pthread_mutexattr_default, calloc);
189         else if (*mutex == THR_ADAPTIVE_MUTEX_INITIALIZER)
190                 ret = mutex_init(mutex, &_pthread_mutexattr_adaptive_default, calloc);
191         else
192                 ret = 0;
193         THR_LOCK_RELEASE(thread, &_mutex_static_lock);
194
195         return (ret);
196 }
197
198 static void
199 set_inherited_priority(struct pthread *curthread, struct pthread_mutex *m)
200 {
201         struct pthread_mutex *m2;
202
203         m2 = TAILQ_LAST(&curthread->pp_mutexq, mutex_queue);
204         if (m2 != NULL)
205                 m->m_lock.m_ceilings[1] = m2->m_lock.m_ceilings[0];
206         else
207                 m->m_lock.m_ceilings[1] = -1;
208 }
209
210 int
211 __pthread_mutex_init(pthread_mutex_t *mutex,
212     const pthread_mutexattr_t *mutex_attr)
213 {
214         return mutex_init(mutex, mutex_attr ? *mutex_attr : NULL, calloc);
215 }
216
217 /* This function is used internally by malloc. */
218 int
219 _pthread_mutex_init_calloc_cb(pthread_mutex_t *mutex,
220     void *(calloc_cb)(size_t, size_t))
221 {
222         static const struct pthread_mutex_attr attr = {
223                 .m_type = PTHREAD_MUTEX_NORMAL,
224                 .m_protocol = PTHREAD_PRIO_NONE,
225                 .m_ceiling = 0
226         };
227         int ret;
228
229         ret = mutex_init(mutex, &attr, calloc_cb);
230         if (ret == 0)
231                 (*mutex)->m_flags |= PMUTEX_FLAG_PRIVATE;
232         return (ret);
233 }
234
235 void
236 _mutex_fork(struct pthread *curthread)
237 {
238         struct pthread_mutex *m;
239
240         /*
241          * Fix mutex ownership for child process.
242          * note that process shared mutex should not
243          * be inherited because owner is forking thread
244          * which is in parent process, they should be
245          * removed from the owned mutex list, current,
246          * process shared mutex is not supported, so I
247          * am not worried.
248          */
249
250         TAILQ_FOREACH(m, &curthread->mutexq, m_qe)
251                 m->m_lock.m_owner = TID(curthread);
252         TAILQ_FOREACH(m, &curthread->pp_mutexq, m_qe)
253                 m->m_lock.m_owner = TID(curthread) | UMUTEX_CONTESTED;
254 }
255
256 int
257 _pthread_mutex_destroy(pthread_mutex_t *mutex)
258 {
259         pthread_mutex_t m;
260         int ret;
261
262         m = *mutex;
263         if (m < THR_MUTEX_DESTROYED) {
264                 ret = 0;
265         } else if (m == THR_MUTEX_DESTROYED) {
266                 ret = EINVAL;
267         } else {
268                 if (m->m_owner != NULL) {
269                         ret = EBUSY;
270                 } else {
271                         *mutex = THR_MUTEX_DESTROYED;
272                         MUTEX_ASSERT_NOT_OWNED(m);
273                         free(m);
274                         ret = 0;
275                 }
276         }
277
278         return (ret);
279 }
280
281 #define ENQUEUE_MUTEX(curthread, m)                                     \
282         do {                                                            \
283                 (m)->m_owner = curthread;                               \
284                 /* Add to the list of owned mutexes: */                 \
285                 MUTEX_ASSERT_NOT_OWNED((m));                            \
286                 if (((m)->m_lock.m_flags & UMUTEX_PRIO_PROTECT) == 0)   \
287                         TAILQ_INSERT_TAIL(&curthread->mutexq, (m), m_qe);\
288                 else                                                    \
289                         TAILQ_INSERT_TAIL(&curthread->pp_mutexq, (m), m_qe);\
290         } while (0)
291
292 #define DEQUEUE_MUTEX(curthread, m)                                     \
293                 (m)->m_owner = NULL;                                    \
294                 MUTEX_ASSERT_IS_OWNED(m);                               \
295                 if (__predict_true(((m)->m_lock.m_flags & UMUTEX_PRIO_PROTECT) == 0)) \
296                         TAILQ_REMOVE(&curthread->mutexq, (m), m_qe);            \
297                 else {                                                  \
298                         TAILQ_REMOVE(&curthread->pp_mutexq, (m), m_qe); \
299                         set_inherited_priority(curthread, m);           \
300                 }                                                       \
301                 MUTEX_INIT_LINK(m);
302
303 #define CHECK_AND_INIT_MUTEX                                            \
304         if (__predict_false((m = *mutex) <= THR_MUTEX_DESTROYED)) {     \
305                 if (m == THR_MUTEX_DESTROYED)                           \
306                         return (EINVAL);                                \
307                 int ret;                                                \
308                 ret = init_static(_get_curthread(), mutex);             \
309                 if (ret)                                                \
310                         return (ret);                                   \
311                 m = *mutex;                                             \
312         }
313
314 static int
315 mutex_trylock_common(pthread_mutex_t *mutex)
316 {
317         struct pthread *curthread = _get_curthread();
318         struct pthread_mutex *m = *mutex;
319         uint32_t id;
320         int ret;
321
322         id = TID(curthread);
323         if (m->m_flags & PMUTEX_FLAG_PRIVATE)
324                 THR_CRITICAL_ENTER(curthread);
325         ret = _thr_umutex_trylock(&m->m_lock, id);
326         if (__predict_true(ret == 0)) {
327                 ENQUEUE_MUTEX(curthread, m);
328         } else if (m->m_owner == curthread) {
329                 ret = mutex_self_trylock(m);
330         } /* else {} */
331         if (ret && (m->m_flags & PMUTEX_FLAG_PRIVATE))
332                 THR_CRITICAL_LEAVE(curthread);
333         return (ret);
334 }
335
336 int
337 __pthread_mutex_trylock(pthread_mutex_t *mutex)
338 {
339         struct pthread_mutex *m;
340
341         CHECK_AND_INIT_MUTEX
342
343         return (mutex_trylock_common(mutex));
344 }
345
346 static int
347 mutex_lock_sleep(struct pthread *curthread, struct pthread_mutex *m,
348         const struct timespec *abstime)
349 {
350         uint32_t        id, owner;
351         int     count;
352         int     ret;
353
354         if (m->m_owner == curthread)
355                 return mutex_self_lock(m, abstime);
356
357         id = TID(curthread);
358         /*
359          * For adaptive mutexes, spin for a bit in the expectation
360          * that if the application requests this mutex type then
361          * the lock is likely to be released quickly and it is
362          * faster than entering the kernel
363          */
364         if (__predict_false(
365                 (m->m_lock.m_flags & 
366                  (UMUTEX_PRIO_PROTECT | UMUTEX_PRIO_INHERIT)) != 0))
367                         goto sleep_in_kernel;
368
369         if (!_thr_is_smp)
370                 goto yield_loop;
371
372         count = m->m_spinloops;
373         while (count--) {
374                 owner = m->m_lock.m_owner;
375                 if ((owner & ~UMUTEX_CONTESTED) == 0) {
376                         if (atomic_cmpset_acq_32(&m->m_lock.m_owner, owner, id|owner)) {
377                                 ret = 0;
378                                 goto done;
379                         }
380                 }
381                 CPU_SPINWAIT;
382         }
383
384 yield_loop:
385         count = m->m_yieldloops;
386         while (count--) {
387                 _sched_yield();
388                 owner = m->m_lock.m_owner;
389                 if ((owner & ~UMUTEX_CONTESTED) == 0) {
390                         if (atomic_cmpset_acq_32(&m->m_lock.m_owner, owner, id|owner)) {
391                                 ret = 0;
392                                 goto done;
393                         }
394                 }
395         }
396
397 sleep_in_kernel:
398         if (abstime == NULL) {
399                 ret = __thr_umutex_lock(&m->m_lock, id);
400         } else if (__predict_false(
401                    abstime->tv_nsec < 0 ||
402                    abstime->tv_nsec >= 1000000000)) {
403                 ret = EINVAL;
404         } else {
405                 ret = __thr_umutex_timedlock(&m->m_lock, id, abstime);
406         }
407 done:
408         if (ret == 0)
409                 ENQUEUE_MUTEX(curthread, m);
410
411         return (ret);
412 }
413
414 static inline int
415 mutex_lock_common(struct pthread_mutex *m,
416         const struct timespec *abstime, int cvattach)
417 {
418         struct pthread *curthread  = _get_curthread();
419         int ret;
420
421         if (!cvattach && m->m_flags & PMUTEX_FLAG_PRIVATE)
422                 THR_CRITICAL_ENTER(curthread);
423         if (_thr_umutex_trylock2(&m->m_lock, TID(curthread)) == 0) {
424                 ENQUEUE_MUTEX(curthread, m);
425                 ret = 0;
426         } else {
427                 ret = mutex_lock_sleep(curthread, m, abstime);
428         }
429         if (ret && (m->m_flags & PMUTEX_FLAG_PRIVATE) && !cvattach)
430                 THR_CRITICAL_LEAVE(curthread);
431         return (ret);
432 }
433
434 int
435 __pthread_mutex_lock(pthread_mutex_t *mutex)
436 {
437         struct pthread_mutex    *m;
438
439         _thr_check_init();
440
441         CHECK_AND_INIT_MUTEX
442
443         return (mutex_lock_common(m, NULL, 0));
444 }
445
446 int
447 __pthread_mutex_timedlock(pthread_mutex_t *mutex, const struct timespec *abstime)
448 {
449         struct pthread_mutex    *m;
450
451         _thr_check_init();
452
453         CHECK_AND_INIT_MUTEX
454
455         return (mutex_lock_common(m, abstime, 0));
456 }
457
458 int
459 _pthread_mutex_unlock(pthread_mutex_t *mutex)
460 {
461         struct pthread_mutex *mp;
462
463         mp = *mutex;
464         return (mutex_unlock_common(mp, 0));
465 }
466
467 int
468 _mutex_cv_lock(struct pthread_mutex *m, int count)
469 {
470         int     error;
471
472         error = mutex_lock_common(m, NULL, 1);
473         if (error == 0)
474                 m->m_count = count;
475         return (error);
476 }
477
478 int
479 _mutex_cv_unlock(struct pthread_mutex *m, int *count)
480 {
481
482         /*
483          * Clear the count in case this is a recursive mutex.
484          */
485         *count = m->m_count;
486         m->m_count = 0;
487         (void)mutex_unlock_common(m, 1);
488         return (0);
489 }
490
491 int
492 _mutex_cv_attach(struct pthread_mutex *m, int count)
493 {
494         struct pthread *curthread = _get_curthread();
495
496         ENQUEUE_MUTEX(curthread, m);
497         m->m_count = count;
498         return (0);
499 }
500
501 int
502 _mutex_cv_detach(struct pthread_mutex *mp, int *recurse)
503 {
504         struct pthread *curthread = _get_curthread();
505         int     defered;
506         int     error;
507
508         if ((error = _mutex_owned(curthread, mp)) != 0)
509                 return (error);
510
511         /*
512          * Clear the count in case this is a recursive mutex.
513          */
514         *recurse = mp->m_count;
515         mp->m_count = 0;
516         DEQUEUE_MUTEX(curthread, mp);
517
518         /* Will this happen in real-world ? */
519         if ((mp->m_flags & PMUTEX_FLAG_DEFERED) != 0) {
520                 defered = 1;
521                 mp->m_flags &= ~PMUTEX_FLAG_DEFERED;
522         } else
523                 defered = 0;
524
525         if (defered)  {
526                 _thr_wake_all(curthread->defer_waiters,
527                                 curthread->nwaiter_defer);
528                 curthread->nwaiter_defer = 0;
529         }
530         return (0);
531 }
532
533 static int
534 mutex_self_trylock(struct pthread_mutex *m)
535 {
536         int     ret;
537
538         switch (PMUTEX_TYPE(m->m_flags)) {
539         case PTHREAD_MUTEX_ERRORCHECK:
540         case PTHREAD_MUTEX_NORMAL:
541                 ret = EBUSY; 
542                 break;
543
544         case PTHREAD_MUTEX_RECURSIVE:
545                 /* Increment the lock count: */
546                 if (m->m_count + 1 > 0) {
547                         m->m_count++;
548                         ret = 0;
549                 } else
550                         ret = EAGAIN;
551                 break;
552
553         default:
554                 /* Trap invalid mutex types; */
555                 ret = EINVAL;
556         }
557
558         return (ret);
559 }
560
561 static int
562 mutex_self_lock(struct pthread_mutex *m, const struct timespec *abstime)
563 {
564         struct timespec ts1, ts2;
565         int     ret;
566
567         switch (PMUTEX_TYPE(m->m_flags)) {
568         case PTHREAD_MUTEX_ERRORCHECK:
569         case PTHREAD_MUTEX_ADAPTIVE_NP:
570                 if (abstime) {
571                         if (abstime->tv_sec < 0 || abstime->tv_nsec < 0 ||
572                             abstime->tv_nsec >= 1000000000) {
573                                 ret = EINVAL;
574                         } else {
575                                 clock_gettime(CLOCK_REALTIME, &ts1);
576                                 TIMESPEC_SUB(&ts2, abstime, &ts1);
577                                 __sys_nanosleep(&ts2, NULL);
578                                 ret = ETIMEDOUT;
579                         }
580                 } else {
581                         /*
582                          * POSIX specifies that mutexes should return
583                          * EDEADLK if a recursive lock is detected.
584                          */
585                         ret = EDEADLK; 
586                 }
587                 break;
588
589         case PTHREAD_MUTEX_NORMAL:
590                 /*
591                  * What SS2 define as a 'normal' mutex.  Intentionally
592                  * deadlock on attempts to get a lock you already own.
593                  */
594                 ret = 0;
595                 if (abstime) {
596                         if (abstime->tv_sec < 0 || abstime->tv_nsec < 0 ||
597                             abstime->tv_nsec >= 1000000000) {
598                                 ret = EINVAL;
599                         } else {
600                                 clock_gettime(CLOCK_REALTIME, &ts1);
601                                 TIMESPEC_SUB(&ts2, abstime, &ts1);
602                                 __sys_nanosleep(&ts2, NULL);
603                                 ret = ETIMEDOUT;
604                         }
605                 } else {
606                         ts1.tv_sec = 30;
607                         ts1.tv_nsec = 0;
608                         for (;;)
609                                 __sys_nanosleep(&ts1, NULL);
610                 }
611                 break;
612
613         case PTHREAD_MUTEX_RECURSIVE:
614                 /* Increment the lock count: */
615                 if (m->m_count + 1 > 0) {
616                         m->m_count++;
617                         ret = 0;
618                 } else
619                         ret = EAGAIN;
620                 break;
621
622         default:
623                 /* Trap invalid mutex types; */
624                 ret = EINVAL;
625         }
626
627         return (ret);
628 }
629
630 static int
631 mutex_unlock_common(struct pthread_mutex *m, int cv)
632 {
633         struct pthread *curthread = _get_curthread();
634         uint32_t id;
635         int defered;
636
637         if (__predict_false(m <= THR_MUTEX_DESTROYED)) {
638                 if (m == THR_MUTEX_DESTROYED)
639                         return (EINVAL);
640                 return (EPERM);
641         }
642
643         /*
644          * Check if the running thread is not the owner of the mutex.
645          */
646         if (__predict_false(m->m_owner != curthread))
647                 return (EPERM);
648
649         id = TID(curthread);
650         if (__predict_false(
651                 PMUTEX_TYPE(m->m_flags) == PTHREAD_MUTEX_RECURSIVE &&
652                 m->m_count > 0)) {
653                 m->m_count--;
654         } else {
655                 if ((m->m_flags & PMUTEX_FLAG_DEFERED) != 0) {
656                         defered = 1;
657                         m->m_flags &= ~PMUTEX_FLAG_DEFERED;
658                 } else
659                         defered = 0;
660
661                 DEQUEUE_MUTEX(curthread, m);
662                 _thr_umutex_unlock(&m->m_lock, id);
663
664                 if (curthread->will_sleep == 0 && defered)  {
665                         _thr_wake_all(curthread->defer_waiters,
666                                 curthread->nwaiter_defer);
667                         curthread->nwaiter_defer = 0;
668                 }
669         }
670         if (!cv && m->m_flags & PMUTEX_FLAG_PRIVATE)
671                 THR_CRITICAL_LEAVE(curthread);
672         return (0);
673 }
674
675 int
676 _pthread_mutex_getprioceiling(pthread_mutex_t *mutex,
677                               int *prioceiling)
678 {
679         struct pthread_mutex *m;
680         int ret;
681
682         m = *mutex;
683         if ((m <= THR_MUTEX_DESTROYED) ||
684             (m->m_lock.m_flags & UMUTEX_PRIO_PROTECT) == 0)
685                 ret = EINVAL;
686         else {
687                 *prioceiling = m->m_lock.m_ceilings[0];
688                 ret = 0;
689         }
690
691         return (ret);
692 }
693
694 int
695 _pthread_mutex_setprioceiling(pthread_mutex_t *mutex,
696                               int ceiling, int *old_ceiling)
697 {
698         struct pthread *curthread = _get_curthread();
699         struct pthread_mutex *m, *m1, *m2;
700         int ret;
701
702         m = *mutex;
703         if ((m <= THR_MUTEX_DESTROYED) ||
704             (m->m_lock.m_flags & UMUTEX_PRIO_PROTECT) == 0)
705                 return (EINVAL);
706
707         ret = __thr_umutex_set_ceiling(&m->m_lock, ceiling, old_ceiling);
708         if (ret != 0)
709                 return (ret);
710
711         if (m->m_owner == curthread) {
712                 MUTEX_ASSERT_IS_OWNED(m);
713                 m1 = TAILQ_PREV(m, mutex_queue, m_qe);
714                 m2 = TAILQ_NEXT(m, m_qe);
715                 if ((m1 != NULL && m1->m_lock.m_ceilings[0] > (u_int)ceiling) ||
716                     (m2 != NULL && m2->m_lock.m_ceilings[0] < (u_int)ceiling)) {
717                         TAILQ_REMOVE(&curthread->pp_mutexq, m, m_qe);
718                         TAILQ_FOREACH(m2, &curthread->pp_mutexq, m_qe) {
719                                 if (m2->m_lock.m_ceilings[0] > (u_int)ceiling) {
720                                         TAILQ_INSERT_BEFORE(m2, m, m_qe);
721                                         return (0);
722                                 }
723                         }
724                         TAILQ_INSERT_TAIL(&curthread->pp_mutexq, m, m_qe);
725                 }
726         }
727         return (0);
728 }
729
730 int
731 _pthread_mutex_getspinloops_np(pthread_mutex_t *mutex, int *count)
732 {
733         struct pthread_mutex    *m;
734
735         CHECK_AND_INIT_MUTEX
736
737         *count = m->m_spinloops;
738         return (0);
739 }
740
741 int
742 __pthread_mutex_setspinloops_np(pthread_mutex_t *mutex, int count)
743 {
744         struct pthread_mutex    *m;
745
746         CHECK_AND_INIT_MUTEX
747
748         m->m_spinloops = count;
749         return (0);
750 }
751
752 int
753 _pthread_mutex_getyieldloops_np(pthread_mutex_t *mutex, int *count)
754 {
755         struct pthread_mutex    *m;
756
757         CHECK_AND_INIT_MUTEX
758
759         *count = m->m_yieldloops;
760         return (0);
761 }
762
763 int
764 __pthread_mutex_setyieldloops_np(pthread_mutex_t *mutex, int count)
765 {
766         struct pthread_mutex    *m;
767
768         CHECK_AND_INIT_MUTEX
769
770         m->m_yieldloops = count;
771         return (0);
772 }
773
774 int
775 _pthread_mutex_isowned_np(pthread_mutex_t *mutex)
776 {
777         struct pthread_mutex    *m;
778
779         m = *mutex;
780         if (m <= THR_MUTEX_DESTROYED)
781                 return (0);
782         return (m->m_owner == _get_curthread());
783 }
784
785 int
786 _mutex_owned(struct pthread *curthread, const struct pthread_mutex *mp)
787 {
788         if (__predict_false(mp <= THR_MUTEX_DESTROYED)) {
789                 if (mp == THR_MUTEX_DESTROYED)
790                         return (EINVAL);
791                 return (EPERM);
792         }
793         if (mp->m_owner != curthread)
794                 return (EPERM);
795         return (0);                  
796 }