Timer not firing fast enough

Hello,

I am trying to create a timer that will toggle a GPIO pin at a specified rate. The fastest that I can get the pin to toggle is 1.77us. But unfortunately, I need to be able to toggle this pin at 0.33us. I have attached my code below on how I am setting the timers and servicing the interrupt. Would anyone be able to make a recommendation as to how I might achieve a shorter period?

Thanks,
Logan

void ConfigureTimer0(void){
    // Enable timer0 peripheral
    MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_TIMER0);
    // Configure timer0 to run once and stop
    MAP_TimerConfigure(TIMER0_BASE, TIMER_CFG_ONE_SHOT_UP);
    TimerClockSourceSet(TIMER0_BASE,TIMER_CLOCK_SYSTEM);

    // Enable timerA interrupt
    MAP_IntEnable(INT_TIMER0A);
    // Enable interrupt for timerA0
    MAP_TimerIntEnable(TIMER0_BASE, TIMER_TIMA_TIMEOUT);
}

void SetPeriodEnableTimer0(unsigned long period){
    // Set timerA0 period
    TimerLoadSet(TIMER0_BASE, TIMER_A, period);
    MAP_TimerEnable(TIMER0_BASE, TIMER_A);
}

void Timer0IntHandler(void){
    // Clear interrupt
    MAP_TimerIntClear(TIMER0_BASE, TIMER_TIMA_TIMEOUT);
    if(GPIOPinRead(GPIO_PORTH_BASE, GPIO_PIN_3)){
        GPIOPinWrite(GPIO_PORTH_BASE, GPIO_PIN_3, 0);
    }
    else{
        GPIOPinWrite(GPIO_PORTH_BASE, GPIO_PIN_3, 255);
    }
    SetPeriodEnableTimer0(1);
}