FreeRTOS 原理 --- 最少剩余可用栈 与 栈溢出检查

函数 uxTaskGetStackHighWaterMark() 可用于获取任务的最少剩余可用栈

#if ( INCLUDE_uxTaskGetStackHighWaterMark == 1 )

    UBaseType_t uxTaskGetStackHighWaterMark( TaskHandle_t xTask )
    {
    TCB_t *pxTCB;
    uint8_t *pucEndOfStack;
    UBaseType_t uxReturn;

        pxTCB = prvGetTCBFromHandle( xTask );

        #if portSTACK_GROWTH < 0
        {
            pucEndOfStack = ( uint8_t * ) pxTCB->pxStack;
        }
        #else
        {
            pucEndOfStack = ( uint8_t * ) pxTCB->pxEndOfStack;
        }
        #endif

        uxReturn = ( UBaseType_t ) prvTaskCheckFreeStackSpace( pucEndOfStack );

        return uxReturn;
    }

#endif /* INCLUDE_uxTaskGetStackHighWaterMark */

 任务创建时，把任务栈的值都初始化为 tskSTACK_FILL_BYTE

    /* Avoid dependency on memset() if it is not required. */
    #if( tskSET_NEW_STACKS_TO_KNOWN_VALUE == 1 )
    {
        /* Fill the stack with a known value to assist debugging. */
        ( void ) memset( pxNewTCB->pxStack, ( int ) tskSTACK_FILL_BYTE, ( size_t ) ulStackDepth * sizeof( StackType_t ) );
    }
    #endif /* tskSET_NEW_STACKS_TO_KNOWN_VALUE */