Re: [PATCH v2] x86/amd: Derive L3 shared_cpu_map from cpu_llc_shared_mask

From	Borislav Petkov <bp@suse.de>
Newsgroups	linux.kernel
Subject	Re: [PATCH v2] x86/amd: Derive L3 shared_cpu_map from cpu_llc_shared_mask
Date	2017-07-30 05:50 +0200
Message-ID	<u8NoS-3og-1@gated-at.bofh.it> (permalink)
References	<u8NoS-3og-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Thu, Jul 27, 2017 at 08:52:35PM -0500, Suravee Suthikulpanit wrote:
> For system with X86_FEATURE_TOPOEXT, current logic use APIC ID to
> calculate shared_cpu_map. However, since APIC IDs are not guaranteed
> to be contiguous for cores across different L3 (e.g. family17h system
> w/ downcore configuration). This breaks the logic, and results in
> incorrect L3 shared_cpu_map.
> 
> Instead, always use the previously calculated cpu_llc_shared_mask of
> each cpu to derive L3 shared_cpu_map. This has been tested on
> family15h and family17h systems, which has L3 and support
> X86_FEATURE_TOPOEXT.
> 
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
> ---
>  arch/x86/kernel/cpu/intel_cacheinfo.c | 32 ++++++++++++++++++--------------
>  1 file changed, 18 insertions(+), 14 deletions(-)

Applied, thanks.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
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Re: [PATCH v2] x86/amd: Derive L3 shared_cpu_map from  cpu_llc_shared_mask Borislav Petkov <bp@suse.de> - 2017-07-30 05:50 +0200

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