xref: /freebsd/sys/contrib/openzfs/lib/libspl/condvar.c (revision 8ac904ce090b1c2e355da8aa122ca2252183f4e1)

// SPDX-License-Identifier: CDDL-1.0
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or https://opensource.org/licenses/CDDL-1.0.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2012, 2018 by Delphix. All rights reserved.
 * Copyright (c) 2016 Actifio, Inc. All rights reserved.
 * Copyright (c) 2025, Klara, Inc.
 */

#include <assert.h>
#include <pthread.h>
#include <errno.h>
#include <string.h>
#include <sys/timer.h>
#include <sys/condvar.h>

/*
 * =========================================================================
 * condition variables
 * =========================================================================
 */

void
cv_init(kcondvar_t *cv, char *name, int type, void *arg)
{
	(void) name, (void) type, (void) arg;
	VERIFY0(pthread_cond_init(cv, NULL));
}

void
cv_destroy(kcondvar_t *cv)
{
	VERIFY0(pthread_cond_destroy(cv));
}

void
cv_wait(kcondvar_t *cv, kmutex_t *mp)
{
	memset(&mp->m_owner, 0, sizeof (pthread_t));
	VERIFY0(pthread_cond_wait(cv, &mp->m_lock));
	mp->m_owner = pthread_self();
}

int
cv_wait_sig(kcondvar_t *cv, kmutex_t *mp)
{
	cv_wait(cv, mp);
	return (1);
}

int
cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime)
{
	int error;
	struct timeval tv;
	struct timespec ts;
	clock_t delta;

	delta = abstime - ddi_get_lbolt();
	if (delta <= 0)
		return (-1);

	VERIFY0(gettimeofday(&tv, NULL));

	ts.tv_sec = tv.tv_sec + delta / hz;
	ts.tv_nsec = tv.tv_usec * NSEC_PER_USEC + (delta % hz) * (NANOSEC / hz);
	if (ts.tv_nsec >= NANOSEC) {
		ts.tv_sec++;
		ts.tv_nsec -= NANOSEC;
	}

	memset(&mp->m_owner, 0, sizeof (pthread_t));
	error = pthread_cond_timedwait(cv, &mp->m_lock, &ts);
	mp->m_owner = pthread_self();

	if (error == ETIMEDOUT)
		return (-1);

	VERIFY0(error);

	return (1);
}

int
cv_timedwait_hires(kcondvar_t *cv, kmutex_t *mp, hrtime_t tim, hrtime_t res,
    int flag)
{
	(void) res;
	int error;
	struct timeval tv;
	struct timespec ts;
	hrtime_t delta;

	ASSERT(flag == 0 || flag == CALLOUT_FLAG_ABSOLUTE);

	delta = tim;
	if (flag & CALLOUT_FLAG_ABSOLUTE)
		delta -= gethrtime();

	if (delta <= 0)
		return (-1);

	VERIFY0(gettimeofday(&tv, NULL));

	ts.tv_sec = tv.tv_sec + delta / NANOSEC;
	ts.tv_nsec = tv.tv_usec * NSEC_PER_USEC + (delta % NANOSEC);
	if (ts.tv_nsec >= NANOSEC) {
		ts.tv_sec++;
		ts.tv_nsec -= NANOSEC;
	}

	memset(&mp->m_owner, 0, sizeof (pthread_t));
	error = pthread_cond_timedwait(cv, &mp->m_lock, &ts);
	mp->m_owner = pthread_self();

	if (error == ETIMEDOUT)
		return (-1);

	VERIFY0(error);

	return (1);
}

void
cv_signal(kcondvar_t *cv)
{
	VERIFY0(pthread_cond_signal(cv));
}

void
cv_broadcast(kcondvar_t *cv)
{
	VERIFY0(pthread_cond_broadcast(cv));
}