2 * Copyright (c) 1998 Daniel Eischen <eischen@vigrid.com>.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
32 * $FreeBSD: src/lib/libpthread/thread/thr_setschedparam.c,v 1.13 2003/04/21 04:02:56 deischen Exp $
33 * $DragonFly: src/lib/libthread_xu/thread/thr_setschedparam.c,v 1.1 2005/02/01 12:38:27 davidxu Exp $
36 #include <sys/param.h>
38 #include "thr_private.h"
40 __weak_reference(_pthread_setschedparam, pthread_setschedparam);
43 _pthread_setschedparam(pthread_t pthread, int policy,
44 const struct sched_param *param)
46 struct pthread *curthread = _get_curthread();
52 if ((param == NULL) || (policy < SCHED_FIFO) || (policy > SCHED_RR)) {
53 /* Return an invalid argument error: */
55 } else if ((param->sched_priority < THR_MIN_PRIORITY) ||
56 (param->sched_priority > THR_MAX_PRIORITY)) {
57 /* Return an unsupported value error. */
60 /* Find the thread in the list of active threads: */
61 } else if ((ret = _thr_ref_add(curthread, pthread, /*include dead*/0))
64 * Lock the threads scheduling queue while we change
67 THR_THREAD_LOCK(curthread, pthread);
68 if (pthread->state == PS_DEAD) {
69 THR_THREAD_UNLOCK(curthread, pthread);
70 _thr_ref_delete(curthread, pthread);
73 in_syncq = pthread->sflags & THR_FLAGS_IN_SYNCQ;
75 /* Set the scheduling policy: */
76 pthread->attr.sched_policy = policy;
78 if (param->sched_priority ==
79 THR_BASE_PRIORITY(pthread->base_priority))
81 * There is nothing to do; unlock the threads
84 THR_THREAD_UNLOCK(curthread, pthread);
87 * Remove the thread from its current priority
88 * queue before any adjustments are made to its
91 old_prio = pthread->active_priority;
92 /* if ((pthread->flags & THR_FLAGS_IN_RUNQ) != 0) */ {
94 /* THR_RUNQ_REMOVE(pthread); */
97 /* Set the thread base priority: */
98 pthread->base_priority &=
99 (THR_SIGNAL_PRIORITY | THR_RT_PRIORITY);
100 pthread->base_priority = param->sched_priority;
102 /* Recalculate the active priority: */
103 pthread->active_priority = MAX(pthread->base_priority,
104 pthread->inherited_priority);
107 if ((pthread->priority_mutex_count > 0) &&
108 (old_prio > pthread->active_priority)) {
110 * POSIX states that if the priority is
111 * being lowered, the thread must be
112 * inserted at the head of the queue for
113 * its priority if it owns any priority
114 * protection or inheritence mutexes.
116 /* THR_RUNQ_INSERT_HEAD(pthread); */
119 /* THR_RUNQ_INSERT_TAIL(pthread)*/ ;
122 /* Unlock the threads scheduling queue: */
123 THR_THREAD_UNLOCK(curthread, pthread);
126 * Check for any mutex priority adjustments. This
127 * includes checking for a priority mutex on which
128 * this thread is waiting.
130 _mutex_notify_priochange(curthread, pthread, in_syncq);
132 _thr_ref_delete(curthread, pthread);