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/*
*
* Portions of this code was derived from the file kern_fork.c and as such
* is subject to the copyrights below.
*
* Copyright (c) 1982, 1986, 1989, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* Copyright (c) 1996 Douglas Santry
*
* This code is subject to the beer copyright. If I chance to meet you in a
* bar and this code helped you in some way, you owe me a beer. Only
* in Germany will I accept domestic beer. This code may or may not work
* and I certainly make no claims as to its fitness for *any* purpose.
*
* $Id: kern_threads.c,v 1.10 1998/12/15 17:38:33 des Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/sysproto.h>
/*
* Low level support for sleep/wakeup paradigm
* If a timeout is specified:
* returns 0 if wakeup
* returns EAGAIN if timed out
* returns EINVAL if error
*
* If a timeout is not specified:
*
* returns time waiting in ticks.
*/
int
thr_sleep(struct proc *p, struct thr_sleep_args *uap) {
int sleepstart;
struct timespec ts;
struct timeval atv;
int error, timo;
timo = 0;
if (uap->timeout != 0) {
/*
* Get timespec struct
*/
if (error = copyin((caddr_t) uap->timeout, (caddr_t) &ts, sizeof ts)) {
p->p_wakeup = 0;
return error;
}
if (ts.tv_nsec < 0 || ts.tv_nsec >= 1000000000) {
p->p_wakeup = 0;
return (EINVAL);
}
TIMESPEC_TO_TIMEVAL(&atv, &ts);
if (itimerfix(&atv)) {
p->p_wakeup = 0;
return (EINVAL);
}
timo = tvtohz(&atv);
}
p->p_retval[0] = 0;
if (p->p_wakeup == 0) {
sleepstart = ticks;
p->p_flag |= P_SINTR;
error = tsleep(p, PRIBIO, "thrslp", timo);
p->p_flag &= ~P_SINTR;
if (error == EWOULDBLOCK) {
p->p_wakeup = 0;
p->p_retval[0] = EAGAIN;
return 0;
}
if (uap->timeout == 0)
p->p_retval[0] = ticks - sleepstart;
}
p->p_wakeup = 0;
return (0);
}
int
thr_wakeup(struct proc *p, struct thr_wakeup_args *uap) {
struct proc *pSlave = p->p_leader;
while(pSlave && (pSlave->p_pid != uap->pid))
pSlave = pSlave->p_peers;
if(pSlave == 0) {
p->p_retval[0] = ESRCH;
return(0);
}
pSlave->p_wakeup++;
if((pSlave->p_stat == SSLEEP) && (pSlave->p_wchan == pSlave)) {
wakeup(pSlave);
return(0);
}
p->p_retval[0] = EAGAIN;
return 0;
}
/*
* General purpose yield system call
*/
int
yield(struct proc *p, struct yield_args *uap) {
int s;
p->p_retval[0] = 0;
s = splhigh();
p->p_priority = MAXPRI;
setrunqueue(p);
p->p_stats->p_ru.ru_nvcsw++;
mi_switch();
splx(s);
return(0);
}
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