posix/src/pthreadsetschedprio.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /*
0004  * Copyright (c) 2016 embedded brains GmbH & Co. KG
0005  *
0006  * Redistribution and use in source and binary forms, with or without
0007  * modification, are permitted provided that the following conditions
0008  * are met:
0009  * 1. Redistributions of source code must retain the above copyright
0010  *    notice, this list of conditions and the following disclaimer.
0011  * 2. Redistributions in binary form must reproduce the above copyright
0012  *    notice, this list of conditions and the following disclaimer in the
0013  *    documentation and/or other materials provided with the distribution.
0014  *
0015  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0016  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0017  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0018  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0019  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0020  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0021  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0022  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0023  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0024  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0025  * POSSIBILITY OF SUCH DAMAGE.
0026  */
0027
0028 #ifdef HAVE_CONFIG_H
0029 #include "config.h"
0030 #endif
0031
0032 #include <pthread.h>
0033 #include <errno.h>
0034
0035 #include <rtems/posix/priorityimpl.h>
0036 #include <rtems/posix/threadsup.h>
0037 #include <rtems/score/threadimpl.h>
0038 #include <rtems/score/schedulerimpl.h>
0039
0040 int pthread_setschedprio( pthread_t thread, int prio )
0041 {
0042   Thread_Control          *the_thread;
0043   Per_CPU_Control         *cpu_self;
0044   Thread_queue_Context     queue_context;
0045   const Scheduler_Control *scheduler;
0046   Priority_Control         new_priority;
0047   bool                     valid;
0048
0049   _Thread_queue_Context_initialize( &queue_context );
0050   _Thread_queue_Context_clear_priority_updates( &queue_context );
0051   the_thread = _Thread_Get( thread, &queue_context.Lock_context.Lock_context );
0052
0053   if ( the_thread == NULL ) {
0054     return ESRCH;
0055   }
0056
0057   _Thread_Wait_acquire_critical( the_thread, &queue_context );
0058
0059   scheduler = _Thread_Scheduler_get_home( the_thread );
0060
0061   new_priority = _POSIX_Priority_To_core( scheduler, prio, &valid );
0062   if ( !valid ) {
0063     _Thread_Wait_release( the_thread, &queue_context );
0064     return EINVAL;
0065   }
0066
0067   _Thread_Priority_change(
0068     the_thread,
0069     &the_thread->Real_priority,
0070     new_priority,
0071     PRIORITY_GROUP_FIRST,
0072     &queue_context
0073   );
0074
0075   cpu_self = _Thread_queue_Dispatch_disable( &queue_context );
0076   _Thread_Wait_release( the_thread, &queue_context );
0077
0078   _Thread_Priority_update( &queue_context );
0079
0080   _Thread_Dispatch_enable( cpu_self );
0081   return 0;
0082 }