Function prvYieldForTask

tasks.c:716–815

/*-----------------------------------------------------------*/

static void prvYieldForTask( TCB_t * pxTCB,
                             const BaseType_t xPreemptEqualPriority )
{
    BaseType_t xLowestPriority;
    BaseType_t xTaskPriority;
    BaseType_t xLowestPriorityCore = -1;
    BaseType_t xYieldCount = 0;
    BaseType_t x;
    TaskRunning_t xTaskRunState;

    /* THIS FUNCTION MUST BE CALLED FROM A CRITICAL SECTION */

    configASSERT( pxCurrentTCB->uxCriticalNesting > 0U );

    #if ( ( configRUN_MULTIPLE_PRIORITIES == 0 ) && ( configNUM_CORES > 1 ) )
        {
            /* No task should yield for this one if it is a lower priority
             * than priority level of currently ready tasks. */
            if( pxTCB->uxPriority < uxTopReadyPriority )
            {
                return;
            }
        }
    #endif

    xLowestPriority = ( BaseType_t ) pxTCB->uxPriority;

    if( xPreemptEqualPriority == pdFALSE )
    {
        /* xLowestPriority will be decremented to -1 if the priority of pxTCB
         * is 0. This is ok as we will give system idle tasks a priority of -1 below. */
        --xLowestPriority;
    }

    for( x = ( BaseType_t ) 0; x < ( BaseType_t ) configNUM_CORES; x++ )
    {
        /* System idle tasks are being assigned a priority of tskIDLE_PRIORITY - 1 here */
        xTaskPriority = ( BaseType_t ) pxCurrentTCBs[ x ]->uxPriority - pxCurrentTCBs[ x ]->xIsIdle;
        xTaskRunState = pxCurrentTCBs[ x ]->xTaskRunState;

        if( ( taskTASK_IS_RUNNING( xTaskRunState ) != pdFALSE ) && ( xYieldPendings[ x ] == pdFALSE ) )
        {
            if( xTaskPriority <= xLowestPriority )
            {
                #if ( configNUM_CORES > 1 )
                    #if ( configUSE_CORE_AFFINITY == 1 )
                        if( ( pxTCB->uxCoreAffinityMask & ( 1 << x ) ) != 0 )
                    #endif
                #endif
                {
                    #if ( configUSE_TASK_PREEMPTION_DISABLE == 1 )
                        if( pxCurrentTCBs[ x ]->xPreemptionDisable == pdFALSE )
                    #endif
                    {
                        xLowestPriority = xTaskPriority;
                        xLowestPriorityCore = x;
                    }
                }