CCS/EK-TM4C1294XL: TI-RTOS/EK-TM4C1294XL & spiloopback

Tool/software: Code Composer Studio

Hello,
Thanks to the E2E community, I have a lot of beginner knowledge. First of all, thank you for that.
I have new questions about the thread I created before, but I cannot send a message to the thread.
https://e2e.ti.com/support/microcontrollers/other/f/908/t/845768?tisearch=e2e-sitesearch&keymatch=%20user%3A423814

I completed my studies in TivaWare 2.1.4.178 but I think it would be much better if I use RTOS. So I go back to the beginning and look at RTOS-spiloopback again.
I want to repeat receiving and sending messages and I cannot use "while (1){}".
What do I need to do to send and receive messages on RTOS?

/* XDCtools Header files */
#include <xdc/std.h>
#include <xdc/runtime/System.h>

/* BIOS Header files */
#include <ti/sysbios/BIOS.h>
#include <ti/sysbios/knl/Task.h>

/* TI-RTOS Header files */
#include <ti/drivers/GPIO.h>
#include <ti/drivers/SPI.h>

/* Example/Board Header files */
#include "Board.h"

#define SPI_MSG_LENGTH    26

#define TASKSTACKSIZE     768

/* Allocate buffers in .dma section of memory for concerto devices */
#ifdef MWARE
#pragma DATA_SECTION(masterRxBuffer, ".dma");
#pragma DATA_SECTION(masterTxBuffer, ".dma");
#pragma DATA_SECTION(slaveRxBuffer, ".dma");
#pragma DATA_SECTION(slaveTxBuffer, ".dma");
#endif

Task_Struct task0Struct, task1Struct;
Char task0Stack[TASKSTACKSIZE], task1Stack[TASKSTACKSIZE];

unsigned char masterRxBuffer[SPI_MSG_LENGTH];
unsigned char masterTxBuffer[SPI_MSG_LENGTH] = "Hello, this is master SPI"; //25

unsigned char slaveRxBuffer[SPI_MSG_LENGTH];
unsigned char slaveTxBuffer[SPI_MSG_LENGTH] =  "Hello, this is slave SPI"; //24
/* *  ======== slaveTaskFxn ========
 *  Task function for slave task.
 *
 *  This task runs on a higher priority, since slave
 *  has to be ready for master. Slave SPI sends a
 *  message to master and also receives message from
 *  master. Task for this function is created
 *  statically. See the project's .cfg file.
 */
Void slaveTaskFxn (UArg arg0, UArg arg1)
{
    SPI_Handle slaveSpi;
    SPI_Params slaveSpiParams;
    SPI_Transaction slaveTransaction;
    bool transferOK;

    /* Initialize SPI handle with slave mode */
    SPI_Params_init(&slaveSpiParams);
    slaveSpiParams.mode = SPI_SLAVE;
    slaveSpi = SPI_open(Board_SPI1, &slaveSpiParams);
    if (slaveSpi == NULL) {
        System_abort("Error initializing SPI\n");
    }
    else {
        System_printf("SPI initialized\n");
    }

    /* Initialize slave SPI transaction structure */
    slaveTransaction.count = SPI_MSG_LENGTH;
    slaveTransaction.txBuf = (Ptr)slaveTxBuffer;
    slaveTransaction.rxBuf = (Ptr)slaveRxBuffer;

    /* Initiate SPI transfer */
    transferOK = SPI_transfer(slaveSpi, &slaveTransaction);

    if(transferOK) {
        /* Print contents of slave receive buffer */
        System_printf("Slave: %s\n", slaveRxBuffer);
    }
    else {
        System_printf("Unsuccessful slave SPI transfer");
    }

    /* Deinitialize SPI */
    SPI_close(slaveSpi);
}
/*
 *  ======== masterTaskFxn ========
 *  Task function for master task.
 *
 *  This task runs at a lower priority after the slave
 *  task to ensure it is ready for a transaction.
 *  Master SPI sends a message to slave and also
 *  receives message from slave. Task for this function
 *  is created statically. See the project's .cfg
 *  file.
 */
Void masterTaskFxn (UArg arg0, UArg arg1)
{
    SPI_Handle masterSpi;
    SPI_Transaction masterTransaction;
    bool transferOK;

    /* Initialize SPI handle as default master */
    masterSpi = SPI_open(Board_SPI0, NULL);
    if (masterSpi == NULL) {
        System_abort("Error initializing SPI\n");
    }
    else {
        System_printf("SPI initialized\n");
    }

    /* Initialize master SPI transaction structure */
    masterTransaction.count = SPI_MSG_LENGTH;
    masterTransaction.txBuf = (Ptr)masterTxBuffer;
    masterTransaction.rxBuf = (Ptr)masterRxBuffer;

   /* Initiate SPI transfer */
    transferOK = SPI_transfer(masterSpi, &masterTransaction);

    if(transferOK) {
        /* Print contents of master receive buffer */
        System_printf("Master: %s\n", masterRxBuffer);
    }
    else {
        System_printf("Unsuccessful master SPI transfer");
    }

    /* Deinitialize SPI */
    SPI_close(masterSpi);

    System_printf("Done\n");

    System_flush();
}
/*
 *  ======== main ========
 */
int main(void)
{
    /* Construct BIOS objects */
    Task_Params taskParams;

    /* Call board init functions. */
    Board_initGeneral();
    Board_initGPIO();
    Board_initSPI();


    	/* Construct master/slave Task threads */
           Task_Params_init(&taskParams);
           taskParams.priority = 1;
           taskParams.stackSize = TASKSTACKSIZE;
           taskParams.stack = &task0Stack;
           Task_construct(&task0Struct, (Task_FuncPtr)masterTaskFxn, &taskParams, NULL);

           taskParams.stack = &task1Stack;
           taskParams.priority = 2;
           Task_construct(&task1Struct, (Task_FuncPtr)slaveTaskFxn, &taskParams, NULL);

    /* Turn on user LED */
    GPIO_write(Board_LED0, Board_LED_ON);

    System_printf("Starting the SPI loop-back example\nSystem provider is set to"
                  " SysMin. Halt the target to view any SysMin contents in ROV.\n");
    /* SysMin will only print to the console when you call flush or exit */
    System_flush();

    System_printf("This example requires external wires to be connected to the "
                  "header pins. Please see the Getting Started Guide for "
                  "details.\n");
    /* SysMin will only print to the console when you call flush or exit */

    System_flush();

    /* Start BIOS */

    BIOS_start();

    return (0);
}