linux-kernel - Re: [RFC v3 0/5] Add capacity capping support to the CPU controller

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <20170412121514.GE3093@worktop>
Date:   Wed, 12 Apr 2017 14:15:14 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     Patrick Bellasi <patrick.bellasi@....com>
Cc:     Tejun Heo <tj@...nel.org>, linux-kernel@...r.kernel.org,
        linux-pm@...r.kernel.org, Ingo Molnar <mingo@...hat.com>,
        "Rafael J . Wysocki" <rafael.j.wysocki@...el.com>,
        Paul Turner <pjt@...gle.com>,
        Vincent Guittot <vincent.guittot@...aro.org>,
        John Stultz <john.stultz@...aro.org>,
        Todd Kjos <tkjos@...roid.com>,
        Tim Murray <timmurray@...gle.com>,
        Andres Oportus <andresoportus@...gle.com>,
        Joel Fernandes <joelaf@...gle.com>,
        Juri Lelli <juri.lelli@....com>,
        Chris Redpath <chris.redpath@....com>,
        Morten Rasmussen <morten.rasmussen@....com>,
        Dietmar Eggemann <dietmar.eggemann@....com>
Subject: Re: [RFC v3 0/5] Add capacity capping support to the CPU controller

On Tue, Apr 11, 2017 at 06:58:33PM +0100, Patrick Bellasi wrote:
> We should consider also that at the CPUFreq side we already expose
> knobs like scaling_{min,max}_freq which are much more platform
> dependant than capacity.

So I've always objected to these knobs.

That said; they are a pre-existing user interface so changing them isn't
really feasible much.

But at the very least we should integrate them properly. Which for
schedutil would mean they have to directly modify the relevant CPU
capacity values. Is this currently done? (I think not.)