FreeRTOS 源码注释(prvCheckTasksWaitingTermination)

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/*FreeRTOS 中删除任务是分两步的,第一步 vTaskDelete 将其从各个工作链表中断开,放到xTasksWaitingTermination 链表中,第二步 Idle Task 调用这个函数真正的删除任务。代码很简单,不需要注释了。 */


static void prvCheckTasksWaitingTermination( void )
{
    #if ( INCLUDE_vTaskDelete == 1 )
    {
        portBASE_TYPE xListIsEmpty;

        if( uxTasksDeleted > ( unsigned portBASE_TYPE ) 0 )
        {
            vTaskSuspendAll();
                xListIsEmpty = listLIST_IS_EMPTY( &xTasksWaitingTermination );
            xTaskResumeAll();

            if( xListIsEmpty == pdFALSE )
            {
                tskTCB *pxTCB;

                taskENTER_CRITICAL();
                {
                    pxTCB = ( tskTCB * ) listGET_OWNER_OF_HEAD_ENTRY( ( ( xList * ) &xTasksWaitingTermination ) );
                    vListRemove( &( pxTCB->xGenericListItem ) );
                    --uxCurrentNumberOfTasks;
                    --uxTasksDeleted;
                }
                taskEXIT_CRITICAL();

                prvDeleteTCB( pxTCB );
            }
        }
    }
    #endif
}

static void prvDeleteTCB( tskTCB *pxTCB )
{
    vPortFreeAligned( pxTCB->pxStack );
    vPortFree( pxTCB );
}