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Date:   Wed, 10 May 2023 07:59:37 +0100
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Subject: Re: [PATCH 05/17] trace: energy_model: Add trace event for EM runtime
 modifications
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To:     Pierre Gondois <pierre.gondois@arm.com>
Cc:     dietmar.eggemann@arm.com, rui.zhang@intel.com,
        linux-pm@vger.kernel.org, amit.kucheria@verdurent.com,
        amit.kachhap@gmail.com, daniel.lezcano@linaro.org,
        viresh.kumar@linaro.org, len.brown@intel.com, pavel@ucw.cz,
        rafael@kernel.org, ionela.voinescu@arm.com,
        linux-kernel@vger.kernel.org, rostedt@goodmis.org,
        mhiramat@kernel.org
References: <20230314103357.26010-1-lukasz.luba@arm.com>
 <20230314103357.26010-6-lukasz.luba@arm.com>
 <9994acf8-e0bc-55ce-9012-e36ef3b8ddab@arm.com>
From:   Lukasz Luba <lukasz.luba@arm.com>
In-Reply-To: <9994acf8-e0bc-55ce-9012-e36ef3b8ddab@arm.com>
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On 4/11/23 16:39, Pierre Gondois wrote:
> Hello Lukasz,
> Just a suggestion, maybe it would be good to trace the CPUs affected by

We print the device name in the trace event, which would be the first
CPU in the frequency domain.

> the modification. It is possible to retrieve this information by going
> to /sys/kernel/debug/energy_model/xxx/cpus, but might be simpler when
> parsing a trace.

We don't want to introduce an array of CPUs, or a name like cpus0-3,
which than has to be parsed in more complex way. Also, the other devices
like GPU might use this trace event, so I just wanted to keep it simple
and generic to handle them all.