linux-kernel - Re: [RFC][PATCH 8/9] sched: power: Add initial frequency scaling support to power scheduler

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: <20130712125113.GF20960@e103034-lin>
Date:	Fri, 12 Jul 2013 13:51:13 +0100
From:	Morten Rasmussen <morten.rasmussen@....com>
To:	Arjan van de Ven <arjan@...ux.intel.com>
Cc:	"mingo@...nel.org" <mingo@...nel.org>,
	"peterz@...radead.org" <peterz@...radead.org>,
	"vincent.guittot@...aro.org" <vincent.guittot@...aro.org>,
	"preeti@...ux.vnet.ibm.com" <preeti@...ux.vnet.ibm.com>,
	"alex.shi@...el.com" <alex.shi@...el.com>,
	"efault@....de" <efault@....de>, "pjt@...gle.com" <pjt@...gle.com>,
	"len.brown@...el.com" <len.brown@...el.com>,
	"corbet@....net" <corbet@....net>,
	"akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
	"torvalds@...ux-foundation.org" <torvalds@...ux-foundation.org>,
	"tglx@...utronix.de" <tglx@...utronix.de>,
	Catalin Marinas <Catalin.Marinas@....com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linaro-kernel@...ts.linaro.org" <linaro-kernel@...ts.linaro.org>
Subject: Re: [RFC][PATCH 8/9] sched: power: Add initial frequency scaling
 support to power scheduler

On Wed, Jul 10, 2013 at 02:10:59PM +0100, Arjan van de Ven wrote:
> On 7/9/2013 8:55 AM, Morten Rasmussen wrote:
> > Extends the power scheduler capacity management algorithm to handle
> > frequency scaling and provide basic frequency/P-state selection hints
> > to the power driver.
> >
> > Signed-off-by: Morten Rasmussen <morten.rasmussen@....com>
> > CC: Ingo Molnar <mingo@...nel.org>
> > CC: Peter Zijlstra <peterz@...radead.org>
> > CC: Catalin Marinas <catalin.marinas@....com>
> > ---
> >   kernel/sched/power.c |   33 ++++++++++++++++++++++++++++-----
> >   1 file changed, 28 insertions(+), 5 deletions(-)
> >
> > diff --git a/kernel/sched/power.c b/kernel/sched/power.c
> > index 9e44c0e..5fc32b0 100644
> > --- a/kernel/sched/power.c
> > +++ b/kernel/sched/power.c
> > @@ -21,6 +21,8 @@
> >
> >   #define INTERVAL 5 /* ms */
> >   #define CPU_FULL 90 /* Busy %-age - TODO: Make tunable */
> > +#define CPU_TARGET 80 /* Target busy %-age - TODO: Make tunable */
> > +#define CPU_EMPTY 5 /* Idle noise %-age - TODO: Make tunable */
> >
> 
> to be honest, this is the policy part that really should be in the hardware specific driver
> and not in the scheduler.
> (even if said driver is sort of a "generic library" kind of thing)

I agree that the values should be set by a hardware specific power
driver. Or do you mean that algorithms using this sort of values should
be in the driver?

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/