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 * $FreeBSD$ 33 */ 34 35#include "namespace.h" 36#include <errno.h> 37#include <sys/param.h> 38#include <pthread.h> 39#include "un-namespace.h" 40#include "thr_private.h" 41 42__weak_reference(_pthread_setschedparam, pthread_setschedparam); 43 44int 45_pthread_setschedparam(pthread_t pthread, int policy, 46 const struct sched_param *param) 47{ 48 struct pthread *curthread = _get_curthread(); 49 int in_syncq; 50 int in_readyq = 0; 51 int old_prio; 52 int ret = 0; 53 54 if ((param == NULL) || (policy < SCHED_FIFO) || (policy > SCHED_RR)) { 55 /* Return an invalid argument error: */ 56 ret = EINVAL; 57 } else if ((param->sched_priority < THR_MIN_PRIORITY) || 58 (param->sched_priority > THR_MAX_PRIORITY)) { 59 /* Return an unsupported value error. */ 60 ret = ENOTSUP; 61 62 /* Find the thread in the list of active threads: */ 63 } else if ((ret = _thr_ref_add(curthread, pthread, /*include dead*/0)) 64 == 0) { 65 /* 66 * Lock the threads scheduling queue while we change 67 * its priority: 68 */ 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); 75 return (ESRCH); 76 } 77 in_syncq = pthread->sflags & THR_FLAGS_IN_SYNCQ; 78 79 /* Set the scheduling policy: */ 80 pthread->attr.sched_policy = policy; 81 82 if (param->sched_priority == 83 THR_BASE_PRIORITY(pthread->base_priority)) 84 /* 85 * There is nothing to do; unlock the threads 86 * scheduling queue. 87 */ 88 THR_SCHED_UNLOCK(curthread, pthread); 89 else { 90 /* 91 * Remove the thread from its current priority 92 * queue before any adjustments are made to its 93 * active priority: 94 */ 95 old_prio = pthread->active_priority; 96 if ((pthread->flags & THR_FLAGS_IN_RUNQ) != 0) { 97 in_readyq = 1; 98 THR_RUNQ_REMOVE(pthread); 99 } 100 101 /* Set the thread base priority: */ 102 pthread->base_priority &= 103 (THR_SIGNAL_PRIORITY | THR_RT_PRIORITY); 104 pthread->base_priority = param->sched_priority; 105 106 /* Recalculate the active priority: */ 107 pthread->active_priority = MAX(pthread->base_priority, 108 pthread->inherited_priority); 109 110 if (in_readyq) { 111 if ((pthread->priority_mutex_count > 0) && 112 (old_prio > pthread->active_priority)) { 113 /* 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. 119 */ 120 THR_RUNQ_INSERT_HEAD(pthread); 121 } 122 else 123 THR_RUNQ_INSERT_TAIL(pthread); 124 } 125 126 /* Unlock the threads scheduling queue: */ 127 THR_SCHED_UNLOCK(curthread, pthread); 128 129 /* 130 * Check for any mutex priority adjustments. This 131 * includes checking for a priority mutex on which 132 * this thread is waiting. 133 */ 134 _mutex_notify_priochange(curthread, pthread, in_syncq); 135 } 136 _thr_ref_delete(curthread, pthread); 137 } 138 return (ret); 139} 140