Re: [GIT pull] irq updates for 4.13

From: Linus Torvalds
Date: Tue Jul 04 2017 - 14:34:49 EST

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.