Date: Tue, 4 Jul 2017 21:10:04 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Linus Torvalds <torvalds@linux-foundation.org>
cc: Jens Axboe <axboe@kernel.dk>, Max Gurtovoy <maxg@mellanox.com>,
        Christoph Hellwig <hch@lst.de>, LKML <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Ingo Molnar <mingo@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [GIT pull] irq updates for 4.13
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On Tue, 4 Jul 2017, Linus Torvalds wrote:
> On Tue, Jul 4, 2017 at 8:17 AM, Jens Axboe <axboe@kernel.dk> 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