diff options
Diffstat (limited to 'mit-pthreads/pthreads/schedparam.c')
| -rw-r--r-- | mit-pthreads/pthreads/schedparam.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/mit-pthreads/pthreads/schedparam.c b/mit-pthreads/pthreads/schedparam.c new file mode 100644 index 00000000000..b4b28577022 --- /dev/null +++ b/mit-pthreads/pthreads/schedparam.c @@ -0,0 +1,170 @@ +/* ==== schedparam.c ======================================================= + * Copyright (c) 1994 by Chris Provenzano, proven@mit.edu + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by Chris Provenzano. + * 4. The name of Chris Provenzano may not be used to endorse or promote + * products derived from this software without specific prior written + * permission. + * + * THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL CHRIS PROVENZANO BE LIABLE FOR ANY + * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * Description : Pthread schedparam functions. + * + * 1.38 94/06/15 proven + * -Started coding this file. + */ + +#ifndef lint +static const char rcsid[] = "$Id$"; +#endif + +#include <pthread.h> +#include <sched.h> +#include <errno.h> + +/* ========================================================================== + * sched_get_priority_max + */ +int sched_get_priority_max(int policy) +{ + return PTHREAD_MAX_PRIORITY; +} + +/* ========================================================================== + * sched_get_priority_min + */ +int sched_get_priority_min(int policy) +{ + return PTHREAD_MIN_PRIORITY; +} + +/* Currently only policy is supported */ +/* ========================================================================== + * pthread_setschedparam() + */ +int pthread_setschedparam(pthread_t pthread, int policy, + struct sched_param * param) +{ + enum schedparam_policy new_policy, old_policy; + int ret = OK; + int prio; + + new_policy = policy; + pthread_sched_prevent(); + old_policy = pthread->attr.schedparam_policy; + + if (param) { + if ((param->sched_priority < PTHREAD_MIN_PRIORITY) || + (param->sched_priority > PTHREAD_MAX_PRIORITY)) { + pthread_sched_resume(); + return(EINVAL); + } + prio = param->sched_priority; + } else { + prio = pthread->pthread_priority; + } + + if (pthread == pthread_run) { + switch(new_policy) { + case SCHED_RR: + pthread->attr.schedparam_policy = new_policy; + switch (old_policy) { + case SCHED_FIFO: + machdep_unset_thread_timer(NULL); + default: + pthread->pthread_priority = prio; + break; + } + break; + case SCHED_FIFO: + pthread->attr.schedparam_policy = new_policy; + switch (old_policy) { + case SCHED_IO: + case SCHED_RR: + if (pthread->pthread_priority < prio) { + pthread->pthread_priority = prio; + pthread_sched_resume(); + pthread_yield(); + return(OK); + } + default: + pthread->pthread_priority = prio; + break; + } + break; + case SCHED_IO: + pthread->attr.schedparam_policy = new_policy; + switch (old_policy) { + case SCHED_FIFO: + machdep_unset_thread_timer(NULL); + default: + pthread->pthread_priority = prio; + break; + } + break; + default: + SET_ERRNO(EINVAL); + ret = EINVAL; + break; + } + } else { + switch(new_policy) { + case SCHED_FIFO: + case SCHED_IO: + case SCHED_RR: + if(pthread_prio_queue_remove(pthread_current_prio_queue,pthread) == OK) { + pthread->attr.schedparam_policy = new_policy; + pthread->pthread_priority = prio; + pthread_sched_other_resume(pthread); + } else { + pthread->attr.schedparam_policy = new_policy; + pthread->pthread_priority = prio; + pthread_sched_resume(); + } + return(OK); + break; + default: + SET_ERRNO(EINVAL); + ret = EINVAL; + break; + } + } + + pthread_sched_resume(); + return(ret); +} + +/* ========================================================================== + * pthread_getschedparam() + */ +int pthread_getschedparam(pthread_t pthread, int * policy, + struct sched_param * param) +{ + *policy = pthread->attr.schedparam_policy; + if (param) { + param->sched_priority = pthread->pthread_priority; + } + return(OK); +} + |