/*-
* Copyright (c) 2000 Jake Burkholder <jake@freebsd.org>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _SYS_CONDVAR_H_
#define _SYS_CONDVAR_H_
#ifndef LOCORE
#include <sys/queue.h>
struct mtx;
struct thread;
TAILQ_HEAD(cv_waitq, thread);
/*
* Condition variable. The waiters count is protected by the mutex that
* protects the condition; that is, the mutex that is passed to cv_wait*()
* and is held across calls to cv_signal() and cv_broadcast(). It is an
* optimization to avoid looking up the sleep queue if there are no waiters.
*/
struct cv {
const char *cv_description;
int cv_waiters;
};
#ifdef _KERNEL
void cv_init(struct cv *cvp, const char *desc);
void cv_destroy(struct cv *cvp);
void cv_wait(struct cv *cvp, struct mtx *mp);
void cv_wait_unlock(struct cv *cvp, struct mtx *mp);
int cv_wait_sig(struct cv *cvp, struct mtx *mp);
int cv_timedwait(struct cv *cvp, struct mtx *mp, int timo);
int cv_timedwait_sig(struct cv *cvp, struct mtx *mp, int timo);
void cv_signal(struct cv *cvp);
void cv_broadcastpri(struct cv *cvp, int pri);
#define cv_broadcast(cvp) cv_broadcastpri(cvp, -1)
#define cv_wmesg(cvp) ((cvp)->cv_description)
#endif /* _KERNEL */
#endif /* !LOCORE */
#endif /* _SYS_CONDVAR_H_ */
