Pendsv interrupt

Kernel
1

Hi

I would like to know if FreeRTOS uses the pendsv interrupt?
And if so for what purpose?

thanks

2

Maybe this piece of code ( taken from the ARM_CM4F port ) makes it clear:

void xPortSysTickHandler( void )
{
    /* The SysTick runs at the lowest interrupt priority, so when this interrupt
     * executes all interrupts must be unmasked.  There is therefore no need to
     * save and then restore the interrupt mask value as its value is already
     * known. */
    portDISABLE_INTERRUPTS();
    {
        /* Increment the RTOS tick. */
        if( xTaskIncrementTick() != pdFALSE )
        {
            /* A context switch is required.  Context switching is performed in
             * the PendSV interrupt.  Pend the PendSV interrupt. */
            portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT;
        }
    }
    portENABLE_INTERRUPTS();
}
/*-----------------------------------------------------------*/

The actual code for the PENDSV interrupt can be found in xPortPendSVHandler().

In the above systick function, the PENDSV will be triggered, but a yield will do the same.