freebsd-dev/lib/libkse/thread/thr_nanosleep.c
Daniel Eischen 1cb570c531 Change low-level locking a bit so that we can tell if
a lock is being waitied on.

Fix a races in join and cancellation.

When trying to wait on a CV and the library is not yet
threaded, make it threaded so that waiting actually works.

When trying to nanosleep() and we're not threaded, just
call the system call nanosleep instead of adding the thread
to the wait queue.

Clean up adding/removing new threads to the "all threads queue",
assigning them unique ids, and tracking how many active threads
there are.  Do it all when the thread is added to the scheduling
queue instead of making pthread_create() know how to do it.

Fix a race where a thread could be marked for signal delivery
but it could be exited before we actually add the signal to it.

Other minor cleanups and bug fixes.

Submitted by:	davidxu
Approved by:	re@ (blanket for libpthread)
2003-05-24 02:29:25 +00:00

130 lines
4.3 KiB
C

/*
* Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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.
*
* $FreeBSD$
*/
#include <stdio.h>
#include <errno.h>
#include <pthread.h>
#include "thr_private.h"
__weak_reference(__nanosleep, nanosleep);
int
_nanosleep(const struct timespec *time_to_sleep,
struct timespec *time_remaining)
{
struct pthread *curthread = _get_curthread();
int ret = 0;
struct timespec ts, ts1;
struct timespec remaining_time;
/* Check if the time to sleep is legal: */
if ((time_to_sleep == NULL) || (time_to_sleep->tv_sec < 0) ||
(time_to_sleep->tv_nsec < 0) ||
(time_to_sleep->tv_nsec >= 1000000000)) {
/* Return an EINVAL error : */
errno = EINVAL;
ret = -1;
} else {
if (!_kse_isthreaded())
return __sys_nanosleep(time_to_sleep, time_remaining);
KSE_GET_TOD(curthread->kse, &ts);
/* Calculate the time for the current thread to wake up: */
TIMESPEC_ADD(&curthread->wakeup_time, &ts, time_to_sleep);
THR_LOCK_SWITCH(curthread);
curthread->interrupted = 0;
THR_SET_STATE(curthread, PS_SLEEP_WAIT);
/* Reschedule the current thread to sleep: */
_thr_sched_switch_unlocked(curthread);
/* Calculate the remaining time to sleep: */
KSE_GET_TOD(curthread->kse, &ts1);
remaining_time.tv_sec = time_to_sleep->tv_sec
+ ts.tv_sec - ts1.tv_sec;
remaining_time.tv_nsec = time_to_sleep->tv_nsec
+ ts.tv_nsec - ts1.tv_nsec;
/* Check if the nanosecond field has underflowed: */
if (remaining_time.tv_nsec < 0) {
/* Handle the underflow: */
remaining_time.tv_sec -= 1;
remaining_time.tv_nsec += 1000000000;
}
/* Check if the nanosecond field has overflowed: */
else if (remaining_time.tv_nsec >= 1000000000) {
/* Handle the overflow: */
remaining_time.tv_sec += 1;
remaining_time.tv_nsec -= 1000000000;
}
/* Check if the sleep was longer than the required time: */
if (remaining_time.tv_sec < 0) {
/* Reset the time left: */
remaining_time.tv_sec = 0;
remaining_time.tv_nsec = 0;
}
/* Check if the time remaining is to be returned: */
if (time_remaining != NULL) {
/* Return the actual time slept: */
time_remaining->tv_sec = remaining_time.tv_sec;
time_remaining->tv_nsec = remaining_time.tv_nsec;
}
/* Check if the sleep was interrupted: */
if (curthread->interrupted) {
/* Return an EINTR error : */
errno = EINTR;
ret = -1;
}
}
return (ret);
}
int
__nanosleep(const struct timespec *time_to_sleep,
struct timespec *time_remaining)
{
struct pthread *curthread = _get_curthread();
int ret;
_thr_enter_cancellation_point(curthread);
ret = _nanosleep(time_to_sleep, time_remaining);
_thr_leave_cancellation_point(curthread);
return (ret);
}