Example #1
0
/*
 * There are two possible cases: one is that the previous deadline is missed,
 * The other is that the number of postponed jobs is not 0, but the current
 * deadline is still not expired, i.e., state = RATE_MONOTONIC_ACTIVE.
 */
static rtems_status_code _Rate_monotonic_Block_while_expired(
  Rate_monotonic_Control *the_period,
  rtems_interval          length,
  Thread_Control         *executing,
  ISR_lock_Context       *lock_context
)
{
  /*
   * No matter the just finished jobs in time or not,
   * they are actually missing their deadlines already.
   */
  the_period->state = RATE_MONOTONIC_EXPIRED;

  /*
   * Update statistics from the concluding period
   */
  _Rate_monotonic_Update_statistics( the_period );

  the_period->state = RATE_MONOTONIC_ACTIVE;
  the_period->next_length = length;

  _Rate_monotonic_Release_postponed_job(
      the_period,
      executing,
      length,
      lock_context
  );
  return RTEMS_TIMEOUT;
}
Example #2
0
static rtems_status_code _Rate_monotonic_Block_while_expired(
  Rate_monotonic_Control *the_period,
  rtems_interval          length,
  Thread_Control         *executing,
  ISR_lock_Context       *lock_context
)
{
  /*
   *  Update statistics from the concluding period
   */
  _Rate_monotonic_Update_statistics( the_period );

  the_period->state = RATE_MONOTONIC_ACTIVE;
  the_period->next_length = length;

  _Rate_monotonic_Release_job( the_period, executing, length, lock_context );
  return RTEMS_TIMEOUT;
}
Example #3
0
static rtems_status_code _Rate_monotonic_Block_while_active(
  Rate_monotonic_Control *the_period,
  rtems_interval          length,
  Thread_Control         *executing,
  ISR_lock_Context       *lock_context
)
{
  Per_CPU_Control *cpu_self;
  bool             success;

  /*
   *  Update statistics from the concluding period.
   */
  _Rate_monotonic_Update_statistics( the_period );

  /*
   *  This tells the _Rate_monotonic_Timeout that this task is
   *  in the process of blocking on the period and that we
   *  may be changing the length of the next period.
   */
  the_period->next_length = length;
  executing->Wait.return_argument = the_period;
  _Thread_Wait_flags_set( executing, RATE_MONOTONIC_INTEND_TO_BLOCK );

  cpu_self = _Thread_Dispatch_disable_critical( lock_context );
  _Rate_monotonic_Release( the_period, lock_context );

  _Thread_Set_state( executing, STATES_WAITING_FOR_PERIOD );

  success = _Thread_Wait_flags_try_change_acquire(
    executing,
    RATE_MONOTONIC_INTEND_TO_BLOCK,
    RATE_MONOTONIC_BLOCKED
  );
  if ( !success ) {
    _Assert(
      _Thread_Wait_flags_get( executing ) == RATE_MONOTONIC_READY_AGAIN
    );
    _Thread_Unblock( executing );
  }

  _Thread_Dispatch_enable( cpu_self );
  return RTEMS_SUCCESSFUL;
}
Example #4
0
rtems_status_code rtems_rate_monotonic_period(
  rtems_id       id,
  rtems_interval length
)
{
  Rate_monotonic_Control              *the_period;
  Objects_Locations                    location;
  rtems_status_code                    return_value;
  rtems_rate_monotonic_period_states   local_state;
  ISR_Level                            level;

  the_period = _Rate_monotonic_Get( id, &location );

  switch ( location ) {
    case OBJECTS_LOCAL:
      if ( !_Thread_Is_executing( the_period->owner ) ) {
        _Thread_Enable_dispatch();
        return RTEMS_NOT_OWNER_OF_RESOURCE;
      }

      if ( length == RTEMS_PERIOD_STATUS ) {
        switch ( the_period->state ) {
          case RATE_MONOTONIC_INACTIVE:
            return_value = RTEMS_NOT_DEFINED;
            break;
          case RATE_MONOTONIC_EXPIRED:
          case RATE_MONOTONIC_EXPIRED_WHILE_BLOCKING:
            return_value = RTEMS_TIMEOUT;
            break;
          case RATE_MONOTONIC_ACTIVE:
          default:              /* unreached -- only to remove warnings */
            return_value = RTEMS_SUCCESSFUL;
            break;
        }
        _Thread_Enable_dispatch();
        return( return_value );
      }

      _ISR_Disable( level );
      if ( the_period->state == RATE_MONOTONIC_INACTIVE ) {
        _ISR_Enable( level );

        the_period->next_length = length;

        /*
         *  Baseline statistics information for the beginning of a period.
         */
        _Rate_monotonic_Initiate_statistics( the_period );

        the_period->state = RATE_MONOTONIC_ACTIVE;
        _Watchdog_Initialize(
          &the_period->Timer,
          _Rate_monotonic_Timeout,
          id,
          NULL
        );

        _Watchdog_Insert_ticks( &the_period->Timer, length );
        _Thread_Enable_dispatch();
        return RTEMS_SUCCESSFUL;
      }

      if ( the_period->state == RATE_MONOTONIC_ACTIVE ) {
        /*
         *  Update statistics from the concluding period.
         */
        _Rate_monotonic_Update_statistics( the_period );

        /*
         *  This tells the _Rate_monotonic_Timeout that this task is
         *  in the process of blocking on the period and that we
         *  may be changing the length of the next period.
         */
        the_period->state = RATE_MONOTONIC_OWNER_IS_BLOCKING;
        the_period->next_length = length;

        _ISR_Enable( level );

        _Thread_Executing->Wait.id = the_period->Object.id;
        _Thread_Set_state( _Thread_Executing, STATES_WAITING_FOR_PERIOD );

        /*
         *  Did the watchdog timer expire while we were actually blocking
         *  on it?
         */
        _ISR_Disable( level );
          local_state = the_period->state;
          the_period->state = RATE_MONOTONIC_ACTIVE;
        _ISR_Enable( level );

        /*
         *  If it did, then we want to unblock ourself and continue as
         *  if nothing happen.  The period was reset in the timeout routine.
         */
        if ( local_state == RATE_MONOTONIC_EXPIRED_WHILE_BLOCKING )
          _Thread_Clear_state( _Thread_Executing, STATES_WAITING_FOR_PERIOD );

        _Thread_Enable_dispatch();
        return RTEMS_SUCCESSFUL;
      }

      if ( the_period->state == RATE_MONOTONIC_EXPIRED ) {
        /*
         *  Update statistics from the concluding period
         */
        _Rate_monotonic_Update_statistics( the_period );

        _ISR_Enable( level );

        the_period->state = RATE_MONOTONIC_ACTIVE;
        the_period->next_length = length;

        _Watchdog_Insert_ticks( &the_period->Timer, length );
        _Scheduler_Release_job(the_period->owner, the_period->next_length);
        _Thread_Enable_dispatch();
        return RTEMS_TIMEOUT;
      }

      /*
       *  These should never happen so just return invalid Id.
       *    - RATE_MONOTONIC_OWNER_IS_BLOCKING:
       *    - RATE_MONOTONIC_EXPIRED_WHILE_BLOCKING:
       */
#if defined(RTEMS_MULTIPROCESSING)
    case OBJECTS_REMOTE:            /* should never return this */
#endif
    case OBJECTS_ERROR:
      break;
  }

  return RTEMS_INVALID_ID;
}