xref: /freebsd/lib/libthr/thread/thr_setprio.c (revision 2f02600abfddfc4e9f20dd384a2e729b451e16bd)
1 /*
2  * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the author nor the names of any co-contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #include "namespace.h"
33 #include <pthread.h>
34 #include "un-namespace.h"
35 
36 #include "thr_private.h"
37 
38 __weak_reference(_pthread_setprio, pthread_setprio);
39 
40 int
41 _pthread_setprio(pthread_t pthread, int prio)
42 {
43 	struct pthread	*curthread = _get_curthread();
44 	struct sched_param	param;
45 	int	ret;
46 
47 	param.sched_priority = prio;
48 	if (pthread == curthread)
49 		THR_LOCK(curthread);
50 	else if ((ret = _thr_find_thread(curthread, pthread, /*include dead*/0)))
51 		return (ret);
52 	if (pthread->attr.sched_policy == SCHED_OTHER ||
53 	    pthread->attr.prio == prio) {
54 		pthread->attr.prio = prio;
55 		ret = 0;
56 	} else {
57 		ret = _thr_setscheduler(pthread->tid,
58 			pthread->attr.sched_policy, &param);
59 		if (ret == -1)
60 			ret = errno;
61 		else
62 			pthread->attr.prio = prio;
63 	}
64 	THR_THREAD_UNLOCK(curthread, pthread);
65 	return (ret);
66 }
67