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From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: Thu, 26 Sep 2019 13:45:53 +0200
Message-ID: <CAMuHMdVJ6RbEbKc8s_rhJaUBNnA8sOByq9cJ3KH-qmcqQrm_UQ@mail.gmail.com>
Subject: Re: [PATCH v6] numa: make node_to_cpumask_map() NUMA_NO_NODE aware
To: Peter Zijlstra <peterz@infradead.org>
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 <linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org>

Hi Peter,

On Thu, Sep 26, 2019 at 11:42 AM Peter Zijlstra <peterz@infradead.org> wrote:
> On Wed, Sep 25, 2019 at 03:25:44PM +0200, Michal Hocko wrote:
> > I am sorry but I still do not understand why you consider this whack a
> > mole better then simply live with the fact that NUMA_NO_NODE is a
> > reality and that using the full cpu mask is a reasonable answer to that.
>
> Because it doesn't make physical sense. A device _cannot_ be local to
> all CPUs in a NUMA system.

While it cannot be local to all CPUs, it can be at a uniform (equal) distance
to each CPU node, can't it?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds