Re: [GIT pull] irq updates for 4.13

From: Thomas Gleixner
Date: Tue Jul 04 2017 - 15:10:19 EST


On Tue, 4 Jul 2017, Linus Torvalds wrote:
> On Tue, Jul 4, 2017 at 8:17 AM, Jens Axboe <axboe@xxxxxxxxx> wrote:
> > On 07/03/2017 06:00 PM, Linus Torvalds wrote:
> >>
> >> If they ever do come online, does that get fixed? I don't know.
> >> Somebody should check.
> >
> > Yes, the blk-mq cpu hotplug code updates mappings when CPUs come and
> > go, so that part is fine. That's exercised everytime the laptop is
> > suspended and resumed.
>
> I don't think that's true any more. Commit fe631457ff3e changed it to
> map the initial CPU's sequentially whether they are online or not.
> Only after you run out of hardware queues will we start playing games.
>
> That's what worries me about the conflict - the two changes did very
> different things to the same code. I'd really like somebody to take a
> look at my resolution, and just in general how those two different
> changes work together.

Hmm, I leave that to Christoph. He wrote the irq stuff and reviewed
fe631457ff3e.

Thanks,

tglx