rtems/src/taskmode.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_mode().
0010  */
0011
0012 /*
0013  *  COPYRIGHT (c) 1989-2014.
0014  *  On-Line Applications Research Corporation (OAR).
0015  *
0016  * Redistribution and use in source and binary forms, with or without
0017  * modification, are permitted provided that the following conditions
0018  * are met:
0019  * 1. Redistributions of source code must retain the above copyright
0020  *    notice, this list of conditions and the following disclaimer.
0021  * 2. Redistributions in binary form must reproduce the above copyright
0022  *    notice, this list of conditions and the following disclaimer in the
0023  *    documentation and/or other materials provided with the distribution.
0024  *
0025  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0026  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0027  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0028  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0029  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0030  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0031  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0032  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0033  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0034  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0035  * POSSIBILITY OF SUCH DAMAGE.
0036  */
0037
0038 #ifdef HAVE_CONFIG_H
0039 #include "config.h"
0040 #endif
0041
0042 #include <rtems/rtems/tasksdata.h>
0043 #include <rtems/rtems/modesimpl.h>
0044 #include <rtems/rtems/signalimpl.h>
0045 #include <rtems/score/isrlevel.h>
0046 #include <rtems/score/schedulerimpl.h>
0047 #include <rtems/score/smpimpl.h>
0048 #include <rtems/score/threadimpl.h>
0049
0050 rtems_status_code rtems_task_mode(
0051   rtems_mode  mode_set,
0052   rtems_mode  mask,
0053   rtems_mode *previous_mode_set
0054 )
0055 {
0056   Thread_Control     *executing;
0057   RTEMS_API_Control  *api;
0058   ASR_Information    *asr;
0059   rtems_mode          old_mode;
0060
0061   executing = _Thread_Get_executing();
0062
0063   if ( !previous_mode_set )
0064     return RTEMS_INVALID_ADDRESS;
0065
0066 #if defined(RTEMS_SMP)
0067   if (
0068     ( mask & RTEMS_PREEMPT_MASK ) != 0 &&
0069     !_Modes_Is_preempt_mode_supported( mode_set, executing )
0070   ) {
0071     return RTEMS_NOT_IMPLEMENTED;
0072   }
0073 #endif
0074
0075 #if defined(RTEMS_SMP) || CPU_ENABLE_ROBUST_THREAD_DISPATCH == TRUE
0076   if (
0077     ( mask & RTEMS_INTERRUPT_MASK ) != 0 &&
0078     !_Modes_Is_interrupt_level_supported( mode_set )
0079   ) {
0080     return RTEMS_NOT_IMPLEMENTED;
0081   }
0082 #endif
0083
0084   /*
0085    * Complete all error checking before doing any operations which
0086    * impact the executing thread. There should be no errors returned
0087    * past this point.
0088    */
0089
0090   api = executing->API_Extensions[ THREAD_API_RTEMS ];
0091   asr = &api->Signal;
0092
0093   old_mode  = (executing->is_preemptible) ? RTEMS_PREEMPT : RTEMS_NO_PREEMPT;
0094
0095   if ( executing->CPU_budget.operations == NULL )
0096     old_mode |= RTEMS_NO_TIMESLICE;
0097   else
0098     old_mode |= RTEMS_TIMESLICE;
0099
0100   old_mode |= (asr->is_enabled) ? RTEMS_ASR : RTEMS_NO_ASR;
0101   old_mode |= _ISR_Get_level();
0102
0103   *previous_mode_set = old_mode;
0104
0105   if ( ( mask & RTEMS_TIMESLICE_MASK ) != 0 ) {
0106     _Modes_Apply_timeslice_to_thread( mode_set, executing );
0107   }
0108
0109   if ( ( mask & RTEMS_INTERRUPT_MASK ) != 0 ) {
0110     _ISR_Set_level( _Modes_Get_interrupt_level( mode_set ) );
0111   }
0112
0113   if ( ( mask & ( RTEMS_ASR_MASK | RTEMS_PREEMPT_MASK ) ) != 0 ) {
0114     bool             need_thread_dispatch;
0115     ISR_lock_Context lock_context;
0116
0117     need_thread_dispatch = false;
0118
0119     _Thread_State_acquire( executing, &lock_context );
0120
0121     if ( ( mask & RTEMS_ASR_MASK ) != 0 ) {
0122       bool previous_asr_is_enabled;
0123
0124       previous_asr_is_enabled = asr->is_enabled;
0125       asr->is_enabled = !_Modes_Is_asr_disabled( mode_set );
0126
0127       if (
0128         !previous_asr_is_enabled &&
0129           asr->is_enabled &&
0130           asr->signals_pending != 0
0131       ) {
0132         need_thread_dispatch = true;
0133         _Thread_Append_post_switch_action( executing, &api->Signal_action );
0134       }
0135     }
0136
0137     if ( ( mask & RTEMS_PREEMPT_MASK ) != 0 ) {
0138       bool previous_is_preemptible;
0139
0140       previous_is_preemptible = executing->is_preemptible;
0141       executing->is_preemptible = _Modes_Is_preempt( mode_set );
0142
0143       if ( executing->is_preemptible && !previous_is_preemptible ) {
0144         need_thread_dispatch = true;
0145         _Scheduler_Schedule( executing );
0146       }
0147     }
0148
0149     if ( need_thread_dispatch ) {
0150       Per_CPU_Control *cpu_self;
0151
0152       cpu_self = _Thread_Dispatch_disable_critical( &lock_context );
0153       _Thread_State_release( executing, &lock_context );
0154       _Thread_Dispatch_direct( cpu_self );
0155     } else {
0156       _Thread_State_release( executing, &lock_context );
0157     }
0158   }
0159
0160   return RTEMS_SUCCESSFUL;
0161 }