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
35 #include "namespace.h"
37 #include <sys/param.h>
39 #include "un-namespace.h"
40 #include "thr_private.h"
42 __weak_reference(_pthread_setschedparam, pthread_setschedparam);
45 _pthread_setschedparam(pthread_t pthread, int policy,
46 const struct sched_param *param)
48 struct pthread *curthread = _get_curthread();
54 if ((param == NULL) || (policy < SCHED_FIFO) || (policy > SCHED_RR)) {
55 /* Return an invalid argument error: */
57 } else if ((param->sched_priority < THR_MIN_PRIORITY) ||
58 (param->sched_priority > THR_MAX_PRIORITY)) {
59 /* Return an unsupported value error. */
62 /* Find the thread in the list of active threads: */
63 } else if ((ret = _thr_ref_add(curthread, pthread, /*include dead*/0))
66 * Lock the threads scheduling queue while we change
69 THR_SCHED_LOCK(curthread, pthread);
70 if ((pthread->state == PS_DEAD) ||
71 (pthread->state == PS_DEADLOCK) ||
72 ((pthread->flags & THR_FLAGS_EXITING) != 0)) {
73 THR_SCHED_UNLOCK(curthread, pthread);
74 _thr_ref_delete(curthread, pthread);
77 in_syncq = pthread->sflags & THR_FLAGS_IN_SYNCQ;
79 /* Set the scheduling policy: */
80 pthread->attr.sched_policy = policy;
82 if (param->sched_priority ==
83 THR_BASE_PRIORITY(pthread->base_priority))
85 * There is nothing to do; unlock the threads
88 THR_SCHED_UNLOCK(curthread, pthread);
91 * Remove the thread from its current priority
92 * queue before any adjustments are made to its
95 old_prio = pthread->active_priority;
96 if ((pthread->flags & THR_FLAGS_IN_RUNQ) != 0) {
98 THR_RUNQ_REMOVE(pthread);
101 /* Set the thread base priority: */
102 pthread->base_priority &=
103 (THR_SIGNAL_PRIORITY | THR_RT_PRIORITY);
104 pthread->base_priority = param->sched_priority;
106 /* Recalculate the active priority: */
107 pthread->active_priority = MAX(pthread->base_priority,
108 pthread->inherited_priority);
111 if ((pthread->priority_mutex_count > 0) &&
112 (old_prio > pthread->active_priority)) {
114 * POSIX states that if the priority is
115 * being lowered, the thread must be
116 * inserted at the head of the queue for
117 * its priority if it owns any priority
118 * protection or inheritence mutexes.
120 THR_RUNQ_INSERT_HEAD(pthread);
123 THR_RUNQ_INSERT_TAIL(pthread);
126 /* Unlock the threads scheduling queue: */
127 THR_SCHED_UNLOCK(curthread, pthread);
130 * Check for any mutex priority adjustments. This
131 * includes checking for a priority mutex on which
132 * this thread is waiting.
134 _mutex_notify_priochange(curthread, pthread, in_syncq);
136 _thr_ref_delete(curthread, pthread);