thr_setschedparam.c revision 157457
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 157457 2006-04-04 02:57:49Z davidxu $ 33 */ 34 35#include "namespace.h" 36#include <sys/param.h> 37#include <errno.h> 38#include <pthread.h> 39#include "un-namespace.h" 40 41#include "thr_private.h" 42 43__weak_reference(_pthread_setschedparam, pthread_setschedparam); 44 45/* 46 * Set a thread's scheduling parameters, this should be done 47 * in kernel, doing it in userland is no-op. 48 */ 49int 50_pthread_setschedparam(pthread_t pthread, int policy, 51 const struct sched_param *param) 52{ 53 struct pthread *curthread = _get_curthread(); 54 int ret = 0; 55 56 if ((param == NULL) || (policy < SCHED_FIFO) || (policy > SCHED_RR)) { 57 ret = EINVAL; 58 } else if ((param->sched_priority < THR_MIN_PRIORITY) || 59 (param->sched_priority > THR_MAX_PRIORITY)) { 60 ret = ENOTSUP; 61 } else if ((ret = _thr_ref_add(curthread, pthread, /*include dead*/0)) 62 == 0) { 63 /* 64 * Lock the threads scheduling queue while we change 65 * its priority: 66 */ 67 THR_THREAD_LOCK(curthread, pthread); 68 if (pthread->state == PS_DEAD) { 69 THR_THREAD_UNLOCK(curthread, pthread); 70 _thr_ref_delete(curthread, pthread); 71 return (ESRCH); 72 } 73 74 /* Set the scheduling policy: */ 75 pthread->attr.sched_policy = policy; 76 77 if (param->sched_priority == 78 THR_BASE_PRIORITY(pthread->base_priority)) 79 /* 80 * There is nothing to do; unlock the threads 81 * scheduling queue. 82 */ 83 THR_THREAD_UNLOCK(curthread, pthread); 84 else { 85 pthread->base_priority = param->sched_priority; 86 87 /* Recalculate the active priority: */ 88 pthread->active_priority = MAX(pthread->base_priority, 89 pthread->inherited_priority); 90 91 THR_THREAD_UNLOCK(curthread, pthread); 92 } 93 _thr_ref_delete(curthread, pthread); 94 } 95 return (ret); 96} 97