thr_getschedparam.c revision 144518 
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: head/lib/libthr/thread/thr_getschedparam.c 144518 2005-04-02 01:20:00Z davidxu $
33 */
34
35#include <errno.h>
36#include <pthread.h>
37
38#include "thr_private.h"
39
40__weak_reference(_pthread_getschedparam, pthread_getschedparam);
41
42int
43_pthread_getschedparam(pthread_t pthread, int *policy,
44	struct sched_param *param)
45{
46	struct pthread *curthread = _get_curthread();
47	int ret, tmp;
48
49	if ((param == NULL) || (policy == NULL))
50		/* Return an invalid argument error: */
51		ret = EINVAL;
52	else if (pthread == curthread) {
53		/*
54		 * Avoid searching the thread list when it is the current
55		 * thread.
56		 */
57		THR_THREAD_LOCK(curthread, curthread);
58		param->sched_priority =
59		    THR_BASE_PRIORITY(pthread->base_priority);
60		tmp = pthread->attr.sched_policy;
61		THR_THREAD_UNLOCK(curthread, curthread);
62		*policy = tmp;
63		ret = 0;
64	}
65	/* Find the thread in the list of active threads. */
66	else if ((ret = _thr_ref_add(curthread, pthread, /*include dead*/0))
67	    == 0) {
68		THR_THREAD_LOCK(curthread, pthread);
69		param->sched_priority =
70		    THR_BASE_PRIORITY(pthread->base_priority);
71		tmp = pthread->attr.sched_policy;
72		THR_THREAD_UNLOCK(curthread, pthread);
73		_thr_ref_delete(curthread, pthread);
74		*policy = tmp;
75	}
76	return (ret);
77}
78