thr_setschedparam.c revision 112965
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_setschedparam.c 112965 2003-04-02 03:05:39Z jeff $ 33 */ 34#include <errno.h> 35#include <sys/param.h> 36#include <pthread.h> 37#include "thr_private.h" 38 39__weak_reference(_pthread_setschedparam, pthread_setschedparam); 40 41int 42_pthread_setschedparam(pthread_t pthread, int policy, 43 const struct sched_param *param) 44{ 45 int old_prio, in_readyq = 0, ret = 0; 46 47 if ((param == NULL) || (policy < SCHED_FIFO) || (policy > SCHED_RR)) 48 return (EINVAL); 49 50 if ((param->sched_priority < PTHREAD_MIN_PRIORITY) || 51 (param->sched_priority > PTHREAD_MAX_PRIORITY)) 52 return (ENOTSUP); 53 54 /* Find the thread in the list of active threads: */ 55 if ((ret = _find_thread(pthread)) == 0) { 56 GIANT_LOCK(curthread); 57 58 if (param->sched_priority != 59 PTHREAD_BASE_PRIORITY(pthread->base_priority)) { 60 /* 61 * Remove the thread from its current priority 62 * queue before any adjustments are made to its 63 * active priority: 64 */ 65 old_prio = pthread->active_priority; 66#if 0 /* XXXTHR */ 67 if ((pthread->flags & PTHREAD_FLAGS_IN_PRIOQ) != 0) { 68 in_readyq = 1; 69 PTHREAD_PRIOQ_REMOVE(pthread); 70 } 71#endif 72 73 /* Set the thread base priority: */ 74 pthread->base_priority &= 75 (PTHREAD_SIGNAL_PRIORITY | PTHREAD_RT_PRIORITY); 76 pthread->base_priority = param->sched_priority; 77 78 /* Recalculate the active priority: */ 79 pthread->active_priority = MAX(pthread->base_priority, 80 pthread->inherited_priority); 81#if 0 82 if (in_readyq) { 83 if ((pthread->priority_mutex_count > 0) && 84 (old_prio > pthread->active_priority)) { 85 /* 86 * POSIX states that if the priority is 87 * being lowered, the thread must be 88 * inserted at the head of the queue for 89 * its priority if it owns any priority 90 * protection or inheritence mutexes. 91 */ 92 PTHREAD_PRIOQ_INSERT_HEAD(pthread); 93 } 94 else 95 PTHREAD_PRIOQ_INSERT_TAIL(pthread); 96 } 97#endif 98 99 /* 100 * Check for any mutex priority adjustments. This 101 * includes checking for a priority mutex on which 102 * this thread is waiting. 103 */ 104 _mutex_notify_priochange(pthread); 105 } 106 107 /* Set the scheduling policy: */ 108 pthread->attr.sched_policy = policy; 109 110 GIANT_UNLOCK(curthread); 111 } 112 return(ret); 113} 114