Re: [PATCH v11 04/13] x86/cpufeatures: Add Bandwidth Monitoring Event Configuration feature flag

From: Borislav Petkov
Date: Mon Jan 09 2023 - 16:41:44 EST


On Mon, Jan 09, 2023 at 09:25:32PM +0000, Luck, Tony wrote:
> It feels like the old "rule" was "make it visible in /proc/cpuid" unless there was some
> good reason NOT to do it. But that has resulted in the "flags" line getting ridiculously
> long and hard for humans to read (141 fields with 926 bytes on my Skylake,
> more on more modern CPUs).

Yap, imagine every possible CPUID bit were in there...

> I don't know if we'd break anything if we dropped:
>
> cat_l3 cdp_l3 mba cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local
>
> from /proc/cpuinfo.

I wouldn't mind if we remove them from cpuinfo, frankly.

> Perhaps the "rule" should be written in Documentation/{somewhere}?

This started documenting it:

Documentation/x86/cpuinfo.rst

--
Regards/Gruss,
Boris.

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