xref: /freebsd/lib/libthr/thread/thr_setprio.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
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  * 3. Neither the name of the author nor the names of any co-contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include "namespace.h"
36 #include <pthread.h>
37 #include "un-namespace.h"
38 
39 #include "thr_private.h"
40 
41 __weak_reference(_pthread_setprio, pthread_setprio);
42 
43 int
44 _pthread_setprio(pthread_t pthread, int prio)
45 {
46 	struct pthread	*curthread = _get_curthread();
47 	struct sched_param	param;
48 	int	ret;
49 
50 	param.sched_priority = prio;
51 	if (pthread == curthread)
52 		THR_LOCK(curthread);
53 	else if ((ret = _thr_find_thread(curthread, pthread, /*include dead*/0)))
54 		return (ret);
55 	if (pthread->attr.sched_policy == SCHED_OTHER ||
56 	    pthread->attr.prio == prio) {
57 		pthread->attr.prio = prio;
58 		ret = 0;
59 	} else {
60 		ret = _thr_setscheduler(pthread->tid,
61 			pthread->attr.sched_policy, &param);
62 		if (ret == -1)
63 			ret = errno;
64 		else
65 			pthread->attr.prio = prio;
66 	}
67 	THR_THREAD_UNLOCK(curthread, pthread);
68 	return (ret);
69 }
70