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References: <20210412074309.38484-1-psampat@linux.ibm.com> <20210412074309.38484-2-psampat@linux.ibm.com>
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From:   Doug Smythies <dsmythies@telus.net>
Date:   Sun, 25 Apr 2021 13:47:10 -0700
Message-ID: <CAAYoRsVcVnrBSNu=umdVWtRw3PyuD=c4uaCCcoGQpSWgq3AH=g@mail.gmail.com>
Subject: Re: [RFC v4 1/2] cpuidle: Extract IPI based and timer based wakeup
 latency from idle states
To:     Pratik Rajesh Sampat <psampat@linux.ibm.com>
Cc:     rjw@rjwysocki.net, Daniel Lezcano <daniel.lezcano@linaro.org>,
        shuah@kernel.org, ego@linux.vnet.ibm.com, svaidy@linux.ibm.com,
        Linux PM list <linux-pm@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-kselftest@vger.kernel.org, pratik.r.sampat@gmail.com,
        dsmythies <dsmythies@telus.net>
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Hi Pratik,

On Mon, Apr 12, 2021 at 12:43 AM Pratik Rajesh Sampat
<psampat@linux.ibm.com> wrote:
>
> Introduce a mechanism to fire directed IPIs from a specified source CPU
> to a specified target CPU and measure the difference in time incurred on
> wakeup.
>
> Also, introduce a mechanism to queue a HR timer on a specified CPU and
> subsequently measure the time taken to wakeup the CPU.
>
> Finally define a simple debugfs interface to control the knobs to fire
> the IPI and Timer events on specified CPU and view their incurred idle
> wakeup latencies.
>
> Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com>

Reviewed-by: Doug Smythies <dsmythies@telus.net>