linux-kernel - Re: [PATCH v5 3/4] x86/cacheinfo: Delete global num_cache

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Message-ID: <20240901180838.GC4089@alberich>
Date: Sun, 1 Sep 2024 20:08:38 +0200
From: Andreas Herrmann <aherrmann@...e.de>
To: Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>
Cc: x86@...nel.org, Andreas Herrmann <aherrmann@...e.com>,
	Catalin Marinas <catalin.marinas@....com>,
	Chen Yu <yu.c.chen@...el.com>, Len Brown <len.brown@...el.com>,
	Radu Rendec <rrendec@...hat.com>,
	Pierre Gondois <Pierre.Gondois@....com>, Pu Wen <puwen@...on.cn>,
	"Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
	Sudeep Holla <sudeep.holla@....com>,
	Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
	Will Deacon <will@...nel.org>, Zhang Rui <rui.zhang@...el.com>,
	Nikolay Borisov <nik.borisov@...e.com>,
	Huang Ying <ying.huang@...el.com>,
	Ricardo Neri <ricardo.neri@...el.com>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v5 3/4] x86/cacheinfo: Delete global num_cache_leaves

On Mon, Aug 26, 2024 at 10:16:34PM -0700, Ricardo Neri wrote:
> Linux remembers cpu_cachinfo::num_leaves per CPU, but x86 initializes all
> CPUs from the same global "num_cache_leaves".
> 
> This is erroneous on systems such as Meteor Lake, where each CPU has a
> distinct num_leaves value. Delete the global "num_cache_leaves" and
> initialize num_leaves on each CPU.
> 
> Reviewed-by: Len Brown <len.brown@...el.com>
> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>

Reviewed-by: Andreas Herrmann <aherrmann@...e.de>
Tested-by: Andreas Herrmann <aherrmann@...e.de>

Test was done with a system equipped with AMD Phenom II X6 1055T and
test kernels based on v6.11-rc5-176-g20371ba12063.


Thanks,
Andreas