Re: [PATCH] sched/fair: no sync wakeup from interrupt context

From: Mel Gorman
Date: Thu Aug 04 2022 - 05:52:12 EST


On Thu, Aug 04, 2022 at 10:55:12AM +0200, Ingo Molnar wrote:
>
> * Libo Chen <libo.chen@xxxxxxxxxx> wrote:
>
> > Oh yes, I have no issue with holding the patch back until the regression
> > is fully understood. I was just a little confused on your reference to
> > Mel's comments. [...]
>
> Yeah, that was just me getting confused about which change Mel was
> referring to, as I was looking for external confirmation saying what I was
> thinking about the patch: in_task()/in_interrupt() heuristics rarely do
> well. ;-)
>

Even though I was referring to something else, the reported regression
is still a regression. Prateek's report and what I brought up in
https://lore.kernel.org/all/20220715100738.GD3493@xxxxxxx/ are both simply
examples where changes to affine wakeup can have surprising results.

--
Mel Gorman
SUSE Labs