[Linuxarm] Re: [PATCH] sched/fair: don't use waker's cpu if the waker of sync wake-up is interrupt

On Tue, 2021-04-27 at 04:44 +0000, Song Bao Hua (Barry Song) wrote:

I agree sync hint might have been overused by other kernel subsystem. But this patch will at least fix a case: sync waker is interrupt, in this case, the existing task has nothing to do with waker and wakee, so this case should be excluded from wake_affine_idle().

I long ago tried filtering interrupt wakeups, and met some surprises. Wakeup twiddling always managing to end up being a rob Peter to pay Paul operation despite our best efforts, here's hoping that your pile of stolen cycles is small enough to escape performance bot notice :)

-Mike