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Subject: Re: [PATCH] perf list: Skip the invalid hybrid pmu
To:     Jin Yao <yao.jin@linux.intel.com>, acme@kernel.org,
        jolsa@kernel.org, peterz@infradead.org, mingo@redhat.com,
        alexander.shishkin@linux.intel.com
Cc:     Linux-kernel@vger.kernel.org, kan.liang@intel.com,
        yao.jin@intel.com
References: <20210610051646.4003-1-yao.jin@linux.intel.com>
From:   Andi Kleen <ak@linux.intel.com>
Message-ID: <77380298-b3d5-d165-c8d4-a24b22d15b0c@linux.intel.com>
Date:   Wed, 16 Jun 2021 09:37:47 -0700
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On 6/9/2021 10:16 PM, Jin Yao wrote:
> On hybrid platform, such as Alderlake, if atom CPUs are offlined,
> the kernel still exports the sysfs path '/sys/devices/cpu_atom/' for
> 'cpu_atom' pmu but the file '/sys/devices/cpu_atom/cpus' is empty,
> which indicates this is an invalid pmu.


The patch looks good, but it would probably make sense to fix the kernel 
to avoid this too.

Of course the tools patch would still be needed for older kernels.

-Andi