FreeRTOS SMP: portYIELD_CORE(x)

Kernel
1

Hi, I am done implementing the portYIELD_CORE(x) macro but I don’t completely get how it should be used. The inter-core signaling is currently implemented with a software generated interrupt so I need to install an handler on the cores that can receive this kind of interrupt. At this point my questions are:

  1. Is it possible for a core to use portYIELD_CORE(x) on itself?
  2. Can secondary cores (i.e. cores that do not handle the SysTick interrupt) use portYIELD_CORE(x)?

Thanks

2

No, it is used only to signal other core.

Yes, they can.

3

Ok, thank you. So even the primary core should be able to handle it, right?

4

Yes, because a “secondary” core can unblock a task with a higher priority then the primary core is currently running, but below the priority of the task it is running, so the primary core should switch tasks.

5

Can you help me understand why you mean by “it” here?

6

Yes, sorry, “it” means “the interrupt directed from the core that executes portYIELD_CORE(x) to core x”.

7

Yes, then you are right and @richard-damon already explained the reasoning.