Date: Mon, 17 Oct 2016 00:42:58 +0200
From: Borislav Petkov <bp@alien8.de>
To: hpa@zytor.com
Cc: Ingo Molnar <mingo@kernel.org>, peterz@infradead.org,
        tglx@linutronix.de, dave.hansen@intel.com,
        torvalds@linux-foundation.org, piotr.luc@intel.com, luto@kernel.org,
        brgerst@gmail.com, linux-kernel@vger.kernel.org, dvlasenk@redhat.com,
        jpoimboe@redhat.com, linux-tip-commits@vger.kernel.org
Subject: Re: [tip:x86/urgent] x86/cpufeature: Add AVX512_4VNNIW and
 AVX512_4FMAPS features
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On Sun, Oct 16, 2016 at 11:42:26AM -0700, hpa@zytor.com wrote:
> It's needlessly adding complexity for no reason, at least for the

What complexity? The init_scattered_cpuid_features() version is a
trivial patch in comparison to the current version.

> leaves that are going to add bits over time.

Sure, except they don't get added or we don't need them or whatever, and
we end up with only a small number of bits actually being used.

I don't mind moving them to x86_capability later, when a high percentage
of the respective leaf is actually being used but not for a couple of
bits. That's just waste.

> The x86_capability array is not an expensive resource.

0.1% here, 0.1% there, the creeping bloat thing.

And again, the init_scattered_cpuid_features() hunk is much smaller.

-- 
Regards/Gruss,
    Boris.

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