Re: Re: [RFC PATCH 0/2] elevator: restore old io scheduler on failure in elevator_switch

From: Jinlong Chen
Date: Tue Nov 22 2022 - 07:45:07 EST


> On Tue, Nov 22, 2022 at 08:14:30PM +0800, Jinlong Chen wrote:
> > Mostly failures specific to the intended io scheduler, like consuming more
> > resources than the old one that the system can not afford. But sure it's
> > rare, so do you think I should just correct the outdated document?
>
> I'd be tempted to just documented the behavior, because I think the
> chances are high that if switching to one schedule will fail that
> switching back to the old one will fail as well. I've done a quick
> audit of all three schedulers, and unless I missed something there
> are no other failure cases except for running out of memory.
>
> Maybe a printk to document that switching the scheduler failed are
> we aren't using any scheduler now might be useful, though.

Ok, then I'll send two patches with the document updated and the printk added.

Thanks!
Jinlong Chen