xref: /dflybsd-src/lib/libthread_xu/thread/thr_getschedparam.c (revision a12ef770ba351628dde7e68bd7b722ae54dd554b)
1 /*
2  * Copyright (c) 1998 Daniel Eischen <eischen@vigrid.com>.
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by Daniel Eischen.
16  * 4. Neither the name of the author nor the names of any co-contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY DANIEL EISCHEN AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  * $FreeBSD: src/lib/libpthread/thread/thr_getschedparam.c,v 1.10 2003/07/07 04:28:23 davidxu Exp $
33  * $DragonFly: src/lib/libthread_xu/thread/thr_getschedparam.c,v 1.1 2005/02/01 12:38:27 davidxu Exp $
34  */
35 #include <errno.h>
36 #include <pthread.h>
37 #include "thr_private.h"
38 
39 __weak_reference(_pthread_getschedparam, pthread_getschedparam);
40 
41 int
42 _pthread_getschedparam(pthread_t pthread, int *policy,
43 	struct sched_param *param)
44 {
45 	struct pthread *curthread = _get_curthread();
46 	int ret, tmp;
47 
48 	if ((param == NULL) || (policy == NULL))
49 		/* Return an invalid argument error: */
50 		ret = EINVAL;
51 	else if (pthread == curthread) {
52 		/*
53 		 * Avoid searching the thread list when it is the current
54 		 * thread.
55 		 */
56 		THR_THREAD_LOCK(curthread, curthread);
57 		param->sched_priority =
58 		    THR_BASE_PRIORITY(pthread->base_priority);
59 		tmp = pthread->attr.sched_policy;
60 		THR_THREAD_UNLOCK(curthread, curthread);
61 		*policy = tmp;
62 		ret = 0;
63 	}
64 	/* Find the thread in the list of active threads. */
65 	else if ((ret = _thr_ref_add(curthread, pthread, /*include dead*/0))
66 	    == 0) {
67 		THR_THREAD_LOCK(curthread, pthread);
68 		param->sched_priority =
69 		    THR_BASE_PRIORITY(pthread->base_priority);
70 		tmp = pthread->attr.sched_policy;
71 		THR_THREAD_UNLOCK(curthread, pthread);
72 		_thr_ref_delete(curthread, pthread);
73 		*policy = tmp;
74 	}
75 	return (ret);
76 }
77