rtems/src/taskgetpriority.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup RTEMSImplClassicTask
0007  *
0008  * @brief This source file contains the implementation of
0009  *   rtems_task_get_priority().
0010  */
0011
0012 /*
0013  * Copyright (c) 2016 embedded brains GmbH & Co. KG
0014  *
0015  * Redistribution and use in source and binary forms, with or without
0016  * modification, are permitted provided that the following conditions
0017  * are met:
0018  * 1. Redistributions of source code must retain the above copyright
0019  *    notice, this list of conditions and the following disclaimer.
0020  * 2. Redistributions in binary form must reproduce the above copyright
0021  *    notice, this list of conditions and the following disclaimer in the
0022  *    documentation and/or other materials provided with the distribution.
0023  *
0024  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0025  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0026  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0027  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0028  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0029  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0030  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0031  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0032  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0033  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0034  * POSSIBILITY OF SUCH DAMAGE.
0035  */
0036
0037 #ifdef HAVE_CONFIG_H
0038 #include "config.h"
0039 #endif
0040
0041 #include <rtems/rtems/tasksimpl.h>
0042 #include <rtems/score/schedulerimpl.h>
0043 #include <rtems/score/threadimpl.h>
0044
0045 rtems_status_code rtems_task_get_priority(
0046   rtems_id             task_id,
0047   rtems_id             scheduler_id,
0048   rtems_task_priority *priority
0049 )
0050 {
0051   Thread_Control          *the_thread;
0052   Thread_queue_Context     queue_context;
0053   const Scheduler_Control *scheduler;
0054   const Scheduler_Node    *scheduler_node;
0055   Priority_Control         core_priority;
0056
0057   if ( priority == NULL ) {
0058     return RTEMS_INVALID_ADDRESS;
0059   }
0060
0061   scheduler = _Scheduler_Get_by_id( scheduler_id );
0062   if ( scheduler == NULL ) {
0063     return RTEMS_INVALID_ID;
0064   }
0065
0066   _Thread_queue_Context_initialize( &queue_context );
0067   the_thread = _Thread_Get( task_id,
0068     &queue_context.Lock_context.Lock_context
0069   );
0070
0071   if ( the_thread == NULL ) {
0072 #if defined(RTEMS_MULTIPROCESSING)
0073     if ( _Thread_MP_Is_remote( task_id ) ) {
0074       return RTEMS_ILLEGAL_ON_REMOTE_OBJECT;
0075     }
0076 #endif
0077
0078     return RTEMS_INVALID_ID;
0079   }
0080
0081   scheduler_node = _Thread_Scheduler_get_node_by_index(
0082      the_thread,
0083     _Scheduler_Get_index( scheduler )
0084   );
0085
0086   _Thread_Wait_acquire_critical( the_thread, &queue_context );
0087
0088 #if defined(RTEMS_SMP)
0089   if ( _Priority_Is_empty( &scheduler_node->Wait.Priority ) ) {
0090     _Thread_Wait_release( the_thread, &queue_context );
0091     return RTEMS_NOT_DEFINED;
0092   }
0093 #endif
0094
0095   core_priority = _Priority_Get_priority( &scheduler_node->Wait.Priority );
0096
0097   _Thread_Wait_release( the_thread, &queue_context );
0098   *priority = _RTEMS_Priority_From_core( scheduler, core_priority );
0099   return RTEMS_SUCCESSFUL;
0100 }