1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2000 Jake Burkholder <jake@freebsd.org>. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 */ 30 31 #ifndef _SYS_CONDVAR_H_ 32 #define _SYS_CONDVAR_H_ 33 34 #ifndef LOCORE 35 #include <sys/queue.h> 36 37 struct lock_object; 38 struct thread; 39 40 TAILQ_HEAD(cv_waitq, thread); 41 42 /* 43 * Condition variable. The waiters count is protected by the mutex that 44 * protects the condition; that is, the mutex that is passed to cv_wait*() 45 * and is held across calls to cv_signal() and cv_broadcast(). It is an 46 * optimization to avoid looking up the sleep queue if there are no waiters. 47 */ 48 struct cv { 49 const char *cv_description; 50 int cv_waiters; 51 }; 52 53 #ifdef _KERNEL 54 void cv_init(struct cv *cvp, const char *desc); 55 void cv_destroy(struct cv *cvp); 56 57 void _cv_wait(struct cv *cvp, struct lock_object *lock); 58 void _cv_wait_unlock(struct cv *cvp, struct lock_object *lock); 59 int _cv_wait_sig(struct cv *cvp, struct lock_object *lock); 60 int _cv_timedwait_sbt(struct cv *cvp, struct lock_object *lock, 61 sbintime_t sbt, sbintime_t pr, int flags); 62 int _cv_timedwait_sig_sbt(struct cv *cvp, struct lock_object *lock, 63 sbintime_t sbt, sbintime_t pr, int flags); 64 65 void cv_signal(struct cv *cvp); 66 void cv_broadcastpri(struct cv *cvp, int pri); 67 68 #define cv_wait(cvp, lock) \ 69 _cv_wait((cvp), &(lock)->lock_object) 70 #define cv_wait_unlock(cvp, lock) \ 71 _cv_wait_unlock((cvp), &(lock)->lock_object) 72 #define cv_wait_sig(cvp, lock) \ 73 _cv_wait_sig((cvp), &(lock)->lock_object) 74 #define cv_timedwait(cvp, lock, timo) \ 75 _cv_timedwait_sbt((cvp), &(lock)->lock_object, \ 76 tick_sbt * (timo), 0, C_HARDCLOCK) 77 #define cv_timedwait_sbt(cvp, lock, sbt, pr, flags) \ 78 _cv_timedwait_sbt((cvp), &(lock)->lock_object, (sbt), (pr), (flags)) 79 #define cv_timedwait_sig(cvp, lock, timo) \ 80 _cv_timedwait_sig_sbt((cvp), &(lock)->lock_object, \ 81 tick_sbt * (timo), 0, C_HARDCLOCK) 82 #define cv_timedwait_sig_sbt(cvp, lock, sbt, pr, flags) \ 83 _cv_timedwait_sig_sbt((cvp), &(lock)->lock_object, (sbt), (pr), (flags)) 84 85 #define cv_broadcast(cvp) cv_broadcastpri(cvp, 0) 86 87 #define cv_wmesg(cvp) ((cvp)->cv_description) 88 89 #endif /* _KERNEL */ 90 #endif /* !LOCORE */ 91 #endif /* _SYS_CONDVAR_H_ */ 92