TM4C1294NCPDT: NDK task not pre-empting application task

Hello,

I am building an application based on the TI RTOS tcpEcho example where the tcpWorker task, upon being called, posts a semaphore that then enabled another application task to run. For the sake of the exercise I've made the called application task contain an infinite loop (the task never completes.) I want to know how to make it such that the tcpWorker task can preempt the application task while the application task is running. I've made my application task have priority 1 in the config file but the tcpWorker task still never runs while the applicatoin task is running. What do I need to do to make tcpWorker preempt the application task? (see code snippets below.)

Void tcpWorker(UArg arg0, UArg arg1)
{
    int  clientfd = (int)arg0;
    int  bytesRcvd;
    int  bytesSent;
    char buffer[TCPPACKETSIZE];

    System_printf("tcpWorker: start clientfd = 0x%x\n", clientfd);

    Semaphore_post(semaphore0);

    while ((bytesRcvd = recv(clientfd, buffer, TCPPACKETSIZE, 0)) > 0) {
        bytesSent = send(clientfd, buffer, bytesRcvd, 0);
        if (bytesSent < 0 || bytesSent != bytesRcvd) {
            System_printf("Error: send failed.\n");
            break;
        }
    }
    System_printf("tcpWorker stop clientfd = 0x%x\n", clientfd);

    close(clientfd);
}

//......

void Task_0_Fxn(void){
    while(1){
        Semaphore_pend(semaphore0, BIOS_WAIT_FOREVER);
        while(1){
            //...
        }
    }
}

Thank you