xref: /freebsd/lib/libthr/thread/thr_getschedparam.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 1998 Daniel Eischen <eischen@vigrid.com>.
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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Daniel Eischen.
18  * 4. Neither the name of the author nor the names of any co-contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY DANIEL EISCHEN AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include "namespace.h"
39 #include <sys/types.h>
40 #include <sys/rtprio.h>
41 #include <errno.h>
42 #include <pthread.h>
43 #include "un-namespace.h"
44 
45 #include "thr_private.h"
46 
47 __weak_reference(_pthread_getschedparam, pthread_getschedparam);
48 
49 int
50 _pthread_getschedparam(pthread_t pthread, int * __restrict policy,
51     struct sched_param * __restrict param)
52 {
53 	struct pthread *curthread = _get_curthread();
54 	int ret = 0;
55 
56 	if (policy == NULL || param == NULL)
57 		return (EINVAL);
58 
59 	/*
60 	 * Avoid searching the thread list when it is the current
61 	 * thread.
62 	 */
63 	if (pthread == curthread)
64 		THR_LOCK(curthread);
65 	else if ((ret = _thr_find_thread(curthread, pthread, /*include dead*/0)))
66 		return (ret);
67 	*policy = pthread->attr.sched_policy;
68 	param->sched_priority = pthread->attr.prio;
69 	THR_THREAD_UNLOCK(curthread, pthread);
70 	return (ret);
71 }
72