1331722Seadler/* 2144518Sdavidxu * Copyright (c) 2005 David Xu <davidxu@freebsd.org> 3296162Skib * Copyright (c) 2015 The FreeBSD Foundation 4112918Sjeff * All rights reserved. 5112918Sjeff * 6296162Skib * Portions of this software were developed by Konstantin Belousov 7296162Skib * under sponsorship from the FreeBSD Foundation. 8296162Skib * 9112918Sjeff * Redistribution and use in source and binary forms, with or without 10112918Sjeff * modification, are permitted provided that the following conditions 11112918Sjeff * are met: 12112918Sjeff * 1. Redistributions of source code must retain the above copyright 13144518Sdavidxu * notice unmodified, this list of conditions, and the following 14144518Sdavidxu * disclaimer. 15112918Sjeff * 2. Redistributions in binary form must reproduce the above copyright 16112918Sjeff * notice, this list of conditions and the following disclaimer in the 17112918Sjeff * documentation and/or other materials provided with the distribution. 18112918Sjeff * 19144518Sdavidxu * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20144518Sdavidxu * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21144518Sdavidxu * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22144518Sdavidxu * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23144518Sdavidxu * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24144518Sdavidxu * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25144518Sdavidxu * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26144518Sdavidxu * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27144518Sdavidxu * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28144518Sdavidxu * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29112918Sjeff */ 30144518Sdavidxu 31297706Skib#include <sys/cdefs.h> 32297706Skib__FBSDID("$FreeBSD: stable/11/lib/libthr/thread/thr_cond.c 338707 2018-09-17 02:51:08Z pfg $"); 33297706Skib 34157457Sdavidxu#include "namespace.h" 35112918Sjeff#include <stdlib.h> 36112918Sjeff#include <errno.h> 37112918Sjeff#include <string.h> 38112918Sjeff#include <pthread.h> 39144518Sdavidxu#include <limits.h> 40157457Sdavidxu#include "un-namespace.h" 41144518Sdavidxu 42112918Sjeff#include "thr_private.h" 43112918Sjeff 44297701Skib_Static_assert(sizeof(struct pthread_cond) <= PAGE_SIZE, 45297701Skib "pthread_cond too large"); 46297701Skib 47112918Sjeff/* 48144518Sdavidxu * Prototypes 49115389Smtm */ 50157457Sdavidxuint __pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex); 51157457Sdavidxuint __pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex, 52157457Sdavidxu const struct timespec * abstime); 53144518Sdavidxustatic int cond_init(pthread_cond_t *cond, const pthread_condattr_t *attr); 54144518Sdavidxustatic int cond_wait_common(pthread_cond_t *cond, pthread_mutex_t *mutex, 55144518Sdavidxu const struct timespec *abstime, int cancel); 56216641Sdavidxustatic int cond_signal_common(pthread_cond_t *cond); 57216641Sdavidxustatic int cond_broadcast_common(pthread_cond_t *cond); 58115389Smtm 59115389Smtm/* 60144518Sdavidxu * Double underscore versions are cancellation points. Single underscore 61144518Sdavidxu * versions are not and are provided for libc internal usage (which 62144518Sdavidxu * shouldn't introduce cancellation points). 63112918Sjeff */ 64144518Sdavidxu__weak_reference(__pthread_cond_wait, pthread_cond_wait); 65144518Sdavidxu__weak_reference(__pthread_cond_timedwait, pthread_cond_timedwait); 66112918Sjeff 67112918Sjeff__weak_reference(_pthread_cond_init, pthread_cond_init); 68112918Sjeff__weak_reference(_pthread_cond_destroy, pthread_cond_destroy); 69112918Sjeff__weak_reference(_pthread_cond_signal, pthread_cond_signal); 70112918Sjeff__weak_reference(_pthread_cond_broadcast, pthread_cond_broadcast); 71112918Sjeff 72300971Skib#define CV_PSHARED(cvp) (((cvp)->kcond.c_flags & USYNC_PROCESS_SHARED) != 0) 73216641Sdavidxu 74296162Skibstatic void 75296162Skibcond_init_body(struct pthread_cond *cvp, const struct pthread_cond_attr *cattr) 76296162Skib{ 77296162Skib 78296162Skib if (cattr == NULL) { 79300971Skib cvp->kcond.c_clockid = CLOCK_REALTIME; 80296162Skib } else { 81296162Skib if (cattr->c_pshared) 82300971Skib cvp->kcond.c_flags |= USYNC_PROCESS_SHARED; 83300971Skib cvp->kcond.c_clockid = cattr->c_clockid; 84296162Skib } 85296162Skib} 86296162Skib 87144518Sdavidxustatic int 88144518Sdavidxucond_init(pthread_cond_t *cond, const pthread_condattr_t *cond_attr) 89144518Sdavidxu{ 90296162Skib struct pthread_cond *cvp; 91296162Skib const struct pthread_cond_attr *cattr; 92296162Skib int pshared; 93112918Sjeff 94296162Skib cattr = cond_attr != NULL ? *cond_attr : NULL; 95296162Skib if (cattr == NULL || cattr->c_pshared == PTHREAD_PROCESS_PRIVATE) { 96296162Skib pshared = 0; 97296162Skib cvp = calloc(1, sizeof(struct pthread_cond)); 98296162Skib if (cvp == NULL) 99296162Skib return (ENOMEM); 100144518Sdavidxu } else { 101296162Skib pshared = 1; 102296162Skib cvp = __thr_pshared_offpage(cond, 1); 103296162Skib if (cvp == NULL) 104296162Skib return (EFAULT); 105144518Sdavidxu } 106296162Skib 107296162Skib /* 108296162Skib * Initialise the condition variable structure: 109296162Skib */ 110296162Skib cond_init_body(cvp, cattr); 111296162Skib *cond = pshared ? THR_PSHARED_PTR : cvp; 112296162Skib return (0); 113144518Sdavidxu} 114112918Sjeff 115144518Sdavidxustatic int 116144518Sdavidxuinit_static(struct pthread *thread, pthread_cond_t *cond) 117112918Sjeff{ 118144518Sdavidxu int ret; 119112918Sjeff 120144518Sdavidxu THR_LOCK_ACQUIRE(thread, &_cond_static_lock); 121144518Sdavidxu 122112918Sjeff if (*cond == NULL) 123144518Sdavidxu ret = cond_init(cond, NULL); 124144518Sdavidxu else 125144518Sdavidxu ret = 0; 126112918Sjeff 127144518Sdavidxu THR_LOCK_RELEASE(thread, &_cond_static_lock); 128112918Sjeff 129144518Sdavidxu return (ret); 130112918Sjeff} 131112918Sjeff 132213241Sdavidxu#define CHECK_AND_INIT_COND \ 133296162Skib if (*cond == THR_PSHARED_PTR) { \ 134296162Skib cvp = __thr_pshared_offpage(cond, 0); \ 135296162Skib if (cvp == NULL) \ 136296162Skib return (EINVAL); \ 137296162Skib } else if (__predict_false((cvp = (*cond)) <= THR_COND_DESTROYED)) { \ 138216641Sdavidxu if (cvp == THR_COND_INITIALIZER) { \ 139213241Sdavidxu int ret; \ 140213241Sdavidxu ret = init_static(_get_curthread(), cond); \ 141213241Sdavidxu if (ret) \ 142213241Sdavidxu return (ret); \ 143216641Sdavidxu } else if (cvp == THR_COND_DESTROYED) { \ 144213241Sdavidxu return (EINVAL); \ 145213241Sdavidxu } \ 146216641Sdavidxu cvp = *cond; \ 147213241Sdavidxu } 148213241Sdavidxu 149112918Sjeffint 150338707Spfg_pthread_cond_init(pthread_cond_t * __restrict cond, 151338707Spfg const pthread_condattr_t * __restrict cond_attr) 152112918Sjeff{ 153112918Sjeff 154144518Sdavidxu *cond = NULL; 155144518Sdavidxu return (cond_init(cond, cond_attr)); 156112918Sjeff} 157112918Sjeff 158112918Sjeffint 159112918Sjeff_pthread_cond_destroy(pthread_cond_t *cond) 160112918Sjeff{ 161296162Skib struct pthread_cond *cvp; 162296162Skib int error; 163112918Sjeff 164296162Skib error = 0; 165296162Skib if (*cond == THR_PSHARED_PTR) { 166296162Skib cvp = __thr_pshared_offpage(cond, 0); 167296162Skib if (cvp != NULL) 168296162Skib __thr_pshared_destroy(cond); 169296162Skib *cond = THR_COND_DESTROYED; 170296162Skib } else if ((cvp = *cond) == THR_COND_INITIALIZER) { 171296162Skib /* nothing */ 172296162Skib } else if (cvp == THR_COND_DESTROYED) { 173216641Sdavidxu error = EINVAL; 174296162Skib } else { 175216641Sdavidxu cvp = *cond; 176213241Sdavidxu *cond = THR_COND_DESTROYED; 177216641Sdavidxu free(cvp); 178144518Sdavidxu } 179216641Sdavidxu return (error); 180112918Sjeff} 181112918Sjeff 182211524Sdavidxu/* 183270972Srpaulo * Cancellation behavior: 184211524Sdavidxu * Thread may be canceled at start, if thread is canceled, it means it 185211524Sdavidxu * did not get a wakeup from pthread_cond_signal(), otherwise, it is 186211524Sdavidxu * not canceled. 187211524Sdavidxu * Thread cancellation never cause wakeup from pthread_cond_signal() 188211524Sdavidxu * to be lost. 189211524Sdavidxu */ 190115035Smtmstatic int 191216641Sdavidxucond_wait_kernel(struct pthread_cond *cvp, struct pthread_mutex *mp, 192300043Skib const struct timespec *abstime, int cancel) 193115035Smtm{ 194300043Skib struct pthread *curthread; 195300043Skib int error, error2, recurse, robust; 196112918Sjeff 197300043Skib curthread = _get_curthread(); 198300043Skib robust = _mutex_enter_robust(curthread, mp); 199300043Skib 200216641Sdavidxu error = _mutex_cv_detach(mp, &recurse); 201300043Skib if (error != 0) { 202300043Skib if (robust) 203300043Skib _mutex_leave_robust(curthread, mp); 204216641Sdavidxu return (error); 205300043Skib } 206216641Sdavidxu 207300043Skib if (cancel) 208216641Sdavidxu _thr_cancel_enter2(curthread, 0); 209300971Skib error = _thr_ucond_wait(&cvp->kcond, &mp->m_lock, abstime, 210300971Skib CVWAIT_ABSTIME | CVWAIT_CLOCKID); 211300043Skib if (cancel) 212216641Sdavidxu _thr_cancel_leave(curthread, 0); 213216641Sdavidxu 214112918Sjeff /* 215216641Sdavidxu * Note that PP mutex and ROBUST mutex may return 216216641Sdavidxu * interesting error codes. 217112918Sjeff */ 218216641Sdavidxu if (error == 0) { 219300043Skib error2 = _mutex_cv_lock(mp, recurse, true); 220216641Sdavidxu } else if (error == EINTR || error == ETIMEDOUT) { 221300043Skib error2 = _mutex_cv_lock(mp, recurse, true); 222300043Skib /* 223300043Skib * Do not do cancellation on EOWNERDEAD there. The 224300043Skib * cancellation cleanup handler will use the protected 225300043Skib * state and unlock the mutex without making the state 226300043Skib * consistent and the state will be unrecoverable. 227300043Skib */ 228310016Skib if (error2 == 0 && cancel) { 229310016Skib if (robust) { 230310016Skib _mutex_leave_robust(curthread, mp); 231310016Skib robust = false; 232310016Skib } 233216641Sdavidxu _thr_testcancel(curthread); 234310016Skib } 235300043Skib 236216641Sdavidxu if (error == EINTR) 237216641Sdavidxu error = 0; 238216641Sdavidxu } else { 239216641Sdavidxu /* We know that it didn't unlock the mutex. */ 240300043Skib _mutex_cv_attach(mp, recurse); 241310016Skib if (cancel) { 242310016Skib if (robust) { 243310016Skib _mutex_leave_robust(curthread, mp); 244310016Skib robust = false; 245310016Skib } 246216641Sdavidxu _thr_testcancel(curthread); 247310016Skib } 248300043Skib error2 = 0; 249112918Sjeff } 250300043Skib if (robust) 251300043Skib _mutex_leave_robust(curthread, mp); 252216641Sdavidxu return (error2 != 0 ? error2 : error); 253216641Sdavidxu} 254164877Sdavidxu 255216641Sdavidxu/* 256216641Sdavidxu * Thread waits in userland queue whenever possible, when thread 257216641Sdavidxu * is signaled or broadcasted, it is removed from the queue, and 258216641Sdavidxu * is saved in curthread's defer_waiters[] buffer, but won't be 259216641Sdavidxu * woken up until mutex is unlocked. 260216641Sdavidxu */ 261112918Sjeff 262216641Sdavidxustatic int 263216641Sdavidxucond_wait_user(struct pthread_cond *cvp, struct pthread_mutex *mp, 264300043Skib const struct timespec *abstime, int cancel) 265216641Sdavidxu{ 266300043Skib struct pthread *curthread; 267216641Sdavidxu struct sleepqueue *sq; 268300043Skib int deferred, error, error2, recurse; 269112918Sjeff 270300043Skib curthread = _get_curthread(); 271216641Sdavidxu if (curthread->wchan != NULL) 272301136Scem PANIC("thread %p was already on queue.", curthread); 273216641Sdavidxu 274216641Sdavidxu if (cancel) 275216641Sdavidxu _thr_testcancel(curthread); 276216641Sdavidxu 277216641Sdavidxu _sleepq_lock(cvp); 278216641Sdavidxu /* 279216641Sdavidxu * set __has_user_waiters before unlocking mutex, this allows 280216641Sdavidxu * us to check it without locking in pthread_cond_signal(). 281216641Sdavidxu */ 282216641Sdavidxu cvp->__has_user_waiters = 1; 283300043Skib deferred = 0; 284300043Skib (void)_mutex_cv_unlock(mp, &recurse, &deferred); 285216641Sdavidxu curthread->mutex_obj = mp; 286216641Sdavidxu _sleepq_add(cvp, curthread); 287216641Sdavidxu for(;;) { 288216641Sdavidxu _thr_clear_wake(curthread); 289216641Sdavidxu _sleepq_unlock(cvp); 290300043Skib if (deferred) { 291300043Skib deferred = 0; 292239200Sdavidxu if ((mp->m_lock.m_owner & UMUTEX_CONTESTED) == 0) 293300043Skib (void)_umtx_op_err(&mp->m_lock, 294300043Skib UMTX_OP_MUTEX_WAKE2, mp->m_lock.m_flags, 295300043Skib 0, 0); 296239200Sdavidxu } 297239200Sdavidxu if (curthread->nwaiter_defer > 0) { 298239200Sdavidxu _thr_wake_all(curthread->defer_waiters, 299300043Skib curthread->nwaiter_defer); 300239200Sdavidxu curthread->nwaiter_defer = 0; 301239200Sdavidxu } 302216641Sdavidxu 303300043Skib if (cancel) 304216641Sdavidxu _thr_cancel_enter2(curthread, 0); 305300971Skib error = _thr_sleep(curthread, cvp->kcond.c_clockid, abstime); 306300043Skib if (cancel) 307216641Sdavidxu _thr_cancel_leave(curthread, 0); 308216641Sdavidxu 309216641Sdavidxu _sleepq_lock(cvp); 310216641Sdavidxu if (curthread->wchan == NULL) { 311216641Sdavidxu error = 0; 312216641Sdavidxu break; 313216641Sdavidxu } else if (cancel && SHOULD_CANCEL(curthread)) { 314216641Sdavidxu sq = _sleepq_lookup(cvp); 315300043Skib cvp->__has_user_waiters = _sleepq_remove(sq, curthread); 316216641Sdavidxu _sleepq_unlock(cvp); 317216641Sdavidxu curthread->mutex_obj = NULL; 318300043Skib error2 = _mutex_cv_lock(mp, recurse, false); 319216641Sdavidxu if (!THR_IN_CRITICAL(curthread)) 320216641Sdavidxu _pthread_exit(PTHREAD_CANCELED); 321216641Sdavidxu else /* this should not happen */ 322300043Skib return (error2); 323216641Sdavidxu } else if (error == ETIMEDOUT) { 324216641Sdavidxu sq = _sleepq_lookup(cvp); 325216641Sdavidxu cvp->__has_user_waiters = 326300043Skib _sleepq_remove(sq, curthread); 327216641Sdavidxu break; 328216641Sdavidxu } 329112918Sjeff } 330216641Sdavidxu _sleepq_unlock(cvp); 331216641Sdavidxu curthread->mutex_obj = NULL; 332300043Skib error2 = _mutex_cv_lock(mp, recurse, false); 333300043Skib if (error == 0) 334300043Skib error = error2; 335216641Sdavidxu return (error); 336112918Sjeff} 337112918Sjeff 338216641Sdavidxustatic int 339216641Sdavidxucond_wait_common(pthread_cond_t *cond, pthread_mutex_t *mutex, 340216641Sdavidxu const struct timespec *abstime, int cancel) 341216641Sdavidxu{ 342216641Sdavidxu struct pthread *curthread = _get_curthread(); 343216641Sdavidxu struct pthread_cond *cvp; 344216641Sdavidxu struct pthread_mutex *mp; 345216641Sdavidxu int error; 346216641Sdavidxu 347216641Sdavidxu CHECK_AND_INIT_COND 348216641Sdavidxu 349296162Skib if (*mutex == THR_PSHARED_PTR) { 350296162Skib mp = __thr_pshared_offpage(mutex, 0); 351296162Skib if (mp == NULL) 352296162Skib return (EINVAL); 353296162Skib } else { 354296162Skib mp = *mutex; 355296162Skib } 356216641Sdavidxu 357216641Sdavidxu if ((error = _mutex_owned(curthread, mp)) != 0) 358216641Sdavidxu return (error); 359216641Sdavidxu 360216641Sdavidxu if (curthread->attr.sched_policy != SCHED_OTHER || 361300043Skib (mp->m_lock.m_flags & (UMUTEX_PRIO_PROTECT | UMUTEX_PRIO_INHERIT | 362300971Skib USYNC_PROCESS_SHARED)) != 0 || CV_PSHARED(cvp)) 363300043Skib return (cond_wait_kernel(cvp, mp, abstime, cancel)); 364216641Sdavidxu else 365300043Skib return (cond_wait_user(cvp, mp, abstime, cancel)); 366216641Sdavidxu} 367216641Sdavidxu 368112918Sjeffint 369144518Sdavidxu_pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex) 370112918Sjeff{ 371144518Sdavidxu 372144518Sdavidxu return (cond_wait_common(cond, mutex, NULL, 0)); 373112918Sjeff} 374112918Sjeff 375112918Sjeffint 376338707Spfg__pthread_cond_wait(pthread_cond_t * __restrict cond, 377338707Spfg pthread_mutex_t * __restrict mutex) 378112918Sjeff{ 379144518Sdavidxu 380144518Sdavidxu return (cond_wait_common(cond, mutex, NULL, 1)); 381115277Smtm} 382115277Smtm 383144518Sdavidxuint 384338707Spfg_pthread_cond_timedwait(pthread_cond_t * __restrict cond, 385338707Spfg pthread_mutex_t * __restrict mutex, 386338707Spfg const struct timespec * __restrict abstime) 387115277Smtm{ 388112918Sjeff 389144518Sdavidxu if (abstime == NULL || abstime->tv_sec < 0 || abstime->tv_nsec < 0 || 390144518Sdavidxu abstime->tv_nsec >= 1000000000) 391112918Sjeff return (EINVAL); 392112918Sjeff 393144518Sdavidxu return (cond_wait_common(cond, mutex, abstime, 0)); 394112918Sjeff} 395112918Sjeff 396144518Sdavidxuint 397144518Sdavidxu__pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex, 398144518Sdavidxu const struct timespec *abstime) 399112918Sjeff{ 400112918Sjeff 401144518Sdavidxu if (abstime == NULL || abstime->tv_sec < 0 || abstime->tv_nsec < 0 || 402144518Sdavidxu abstime->tv_nsec >= 1000000000) 403144518Sdavidxu return (EINVAL); 404112918Sjeff 405144518Sdavidxu return (cond_wait_common(cond, mutex, abstime, 1)); 406112918Sjeff} 407112918Sjeff 408144518Sdavidxustatic int 409216641Sdavidxucond_signal_common(pthread_cond_t *cond) 410112918Sjeff{ 411144518Sdavidxu struct pthread *curthread = _get_curthread(); 412216641Sdavidxu struct pthread *td; 413216641Sdavidxu struct pthread_cond *cvp; 414216641Sdavidxu struct pthread_mutex *mp; 415216641Sdavidxu struct sleepqueue *sq; 416216641Sdavidxu int *waddr; 417216641Sdavidxu int pshared; 418112918Sjeff 419112918Sjeff /* 420144518Sdavidxu * If the condition variable is statically initialized, perform dynamic 421144518Sdavidxu * initialization. 422112918Sjeff */ 423213241Sdavidxu CHECK_AND_INIT_COND 424144518Sdavidxu 425216641Sdavidxu pshared = CV_PSHARED(cvp); 426216641Sdavidxu 427300971Skib _thr_ucond_signal(&cvp->kcond); 428216641Sdavidxu 429216641Sdavidxu if (pshared || cvp->__has_user_waiters == 0) 430216641Sdavidxu return (0); 431216641Sdavidxu 432216641Sdavidxu curthread = _get_curthread(); 433216641Sdavidxu waddr = NULL; 434216641Sdavidxu _sleepq_lock(cvp); 435216641Sdavidxu sq = _sleepq_lookup(cvp); 436216641Sdavidxu if (sq == NULL) { 437216641Sdavidxu _sleepq_unlock(cvp); 438216641Sdavidxu return (0); 439216641Sdavidxu } 440216641Sdavidxu 441216641Sdavidxu td = _sleepq_first(sq); 442216641Sdavidxu mp = td->mutex_obj; 443216641Sdavidxu cvp->__has_user_waiters = _sleepq_remove(sq, td); 444300043Skib if (PMUTEX_OWNER_ID(mp) == TID(curthread)) { 445216641Sdavidxu if (curthread->nwaiter_defer >= MAX_DEFER_WAITERS) { 446216641Sdavidxu _thr_wake_all(curthread->defer_waiters, 447300043Skib curthread->nwaiter_defer); 448216641Sdavidxu curthread->nwaiter_defer = 0; 449216641Sdavidxu } 450216641Sdavidxu curthread->defer_waiters[curthread->nwaiter_defer++] = 451300043Skib &td->wake_addr->value; 452300043Skib mp->m_flags |= PMUTEX_FLAG_DEFERRED; 453216641Sdavidxu } else { 454216641Sdavidxu waddr = &td->wake_addr->value; 455216641Sdavidxu } 456216641Sdavidxu _sleepq_unlock(cvp); 457216641Sdavidxu if (waddr != NULL) 458216641Sdavidxu _thr_set_wake(waddr); 459216641Sdavidxu return (0); 460112918Sjeff} 461112918Sjeff 462216641Sdavidxustruct broadcast_arg { 463216641Sdavidxu struct pthread *curthread; 464216641Sdavidxu unsigned int *waddrs[MAX_DEFER_WAITERS]; 465216641Sdavidxu int count; 466216641Sdavidxu}; 467216641Sdavidxu 468216641Sdavidxustatic void 469216641Sdavidxudrop_cb(struct pthread *td, void *arg) 470216641Sdavidxu{ 471216641Sdavidxu struct broadcast_arg *ba = arg; 472216641Sdavidxu struct pthread_mutex *mp; 473216641Sdavidxu struct pthread *curthread = ba->curthread; 474216641Sdavidxu 475216641Sdavidxu mp = td->mutex_obj; 476300043Skib if (PMUTEX_OWNER_ID(mp) == TID(curthread)) { 477216641Sdavidxu if (curthread->nwaiter_defer >= MAX_DEFER_WAITERS) { 478216641Sdavidxu _thr_wake_all(curthread->defer_waiters, 479300043Skib curthread->nwaiter_defer); 480216641Sdavidxu curthread->nwaiter_defer = 0; 481216641Sdavidxu } 482216641Sdavidxu curthread->defer_waiters[curthread->nwaiter_defer++] = 483300043Skib &td->wake_addr->value; 484300043Skib mp->m_flags |= PMUTEX_FLAG_DEFERRED; 485216641Sdavidxu } else { 486216641Sdavidxu if (ba->count >= MAX_DEFER_WAITERS) { 487216641Sdavidxu _thr_wake_all(ba->waddrs, ba->count); 488216641Sdavidxu ba->count = 0; 489216641Sdavidxu } 490216641Sdavidxu ba->waddrs[ba->count++] = &td->wake_addr->value; 491216641Sdavidxu } 492216641Sdavidxu} 493216641Sdavidxu 494216641Sdavidxustatic int 495216641Sdavidxucond_broadcast_common(pthread_cond_t *cond) 496216641Sdavidxu{ 497216641Sdavidxu int pshared; 498216641Sdavidxu struct pthread_cond *cvp; 499216641Sdavidxu struct sleepqueue *sq; 500216641Sdavidxu struct broadcast_arg ba; 501216641Sdavidxu 502216641Sdavidxu /* 503216641Sdavidxu * If the condition variable is statically initialized, perform dynamic 504216641Sdavidxu * initialization. 505216641Sdavidxu */ 506216641Sdavidxu CHECK_AND_INIT_COND 507216641Sdavidxu 508216641Sdavidxu pshared = CV_PSHARED(cvp); 509216641Sdavidxu 510300971Skib _thr_ucond_broadcast(&cvp->kcond); 511216641Sdavidxu 512216641Sdavidxu if (pshared || cvp->__has_user_waiters == 0) 513216641Sdavidxu return (0); 514216641Sdavidxu 515216641Sdavidxu ba.curthread = _get_curthread(); 516216641Sdavidxu ba.count = 0; 517216641Sdavidxu 518216641Sdavidxu _sleepq_lock(cvp); 519216641Sdavidxu sq = _sleepq_lookup(cvp); 520216641Sdavidxu if (sq == NULL) { 521216641Sdavidxu _sleepq_unlock(cvp); 522216641Sdavidxu return (0); 523216641Sdavidxu } 524216641Sdavidxu _sleepq_drop(sq, drop_cb, &ba); 525216641Sdavidxu cvp->__has_user_waiters = 0; 526216641Sdavidxu _sleepq_unlock(cvp); 527216641Sdavidxu if (ba.count > 0) 528216641Sdavidxu _thr_wake_all(ba.waddrs, ba.count); 529216641Sdavidxu return (0); 530216641Sdavidxu} 531216641Sdavidxu 532144518Sdavidxuint 533144518Sdavidxu_pthread_cond_signal(pthread_cond_t * cond) 534112918Sjeff{ 535112918Sjeff 536216641Sdavidxu return (cond_signal_common(cond)); 537112918Sjeff} 538115389Smtm 539144518Sdavidxuint 540144518Sdavidxu_pthread_cond_broadcast(pthread_cond_t * cond) 541115389Smtm{ 542144518Sdavidxu 543216641Sdavidxu return (cond_broadcast_common(cond)); 544115389Smtm} 545