linux-kernel - Re: [PATCH V3 1/3] x86/numa_emulation: refine the calculation of max_emu_nid and dfl_phys

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Message-ID: <20170718105953.GA9149@nazgul.tnic>
Date:   Tue, 18 Jul 2017 13:03:39 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     Wei Yang <richard.weiyang@...il.com>
Cc:     kirill@...temov.name, tglx@...utronix.de, mingo@...hat.com,
        hpa@...or.com, tj@...nel.org, rientjes@...gle.com,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH V3 1/3] x86/numa_emulation: refine the calculation of
 max_emu_nid and dfl_phys_nid

On Sat, Jul 08, 2017 at 09:30:57AM +0800, Wei Yang wrote:
> max_emu_nid and dfl_phys_nid is calculated from emu_nid_to_phys[], which is
> calculated in split_nodes_xxx_interleave(). From the logic in these

$ git grep split_nodes_xxx_interleave
$

> functions, it is assured the emu_nid_to_phys[] has meaningful value if it
> return successfully and ensures dfl_phys_nid will get a valid value.
> 
> This patch removes the error branch to check invalid dfl_phys_nid and

So the check doesn't hurt anyone.

On the contrary - it is an "assertion" of sorts in otherwise complex
code and actually documents the fact that by then emu_nid_to_phys[]
needs to be setup properly.

And it is especially useful if someone decides to change that code in
the future, for whatever reason, and gets to hit that check - it'll even
be helpful in that case.

So I'd vote for keeping that check and not doing anything.

While we're at it, never say "this patch" in a commit message - that is
tautologically obvious.

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
--