On Mon, Nov 02, 2020 at 10:30:50AM +0000, Valentin Schneider wrote: > Now, I'd like to pen exactly why we think it's okay to forgo irq_{enter, > exit}() for that one IRQ and not any other.
Thomas already said a few words on this, but basically scheduler_ipi() is a NOP (*almost*), the IPI has no body. All it does is tickle the return-from-interrupt path. So any setup and tear-down done for the non-existing body is a waste of time.