linux-kernel - Re: [RFC v4 1/2] cpuidle: Extract IPI based and timer based wakeup latency from idle states

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Sun, 25 Apr 2021 13:47:10 -0700
From:   Doug Smythies <dsmythies@...us.net>
To:     Pratik Rajesh Sampat <psampat@...ux.ibm.com>
Cc:     rjw@...ysocki.net, Daniel Lezcano <daniel.lezcano@...aro.org>,
        shuah@...nel.org, ego@...ux.vnet.ibm.com, svaidy@...ux.ibm.com,
        Linux PM list <linux-pm@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-kselftest@...r.kernel.org, pratik.r.sampat@...il.com,
        dsmythies <dsmythies@...us.net>
Subject: Re: [RFC v4 1/2] cpuidle: Extract IPI based and timer based wakeup
 latency from idle states

Hi Pratik,

On Mon, Apr 12, 2021 at 12:43 AM Pratik Rajesh Sampat
<psampat@...ux.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@...ux.ibm.com>

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