Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751597AbaFJKGp (ORCPT ); Tue, 10 Jun 2014 06:06:45 -0400 Received: from fw-tnat.austin.arm.com ([217.140.110.23]:57817 "EHLO collaborate-mta1.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750726AbaFJKGo (ORCPT ); Tue, 10 Jun 2014 06:06:44 -0400 Date: Tue, 10 Jun 2014 11:06:41 +0100 From: Morten Rasmussen To: Peter Zijlstra Cc: Henrik Austad , "linux-kernel@vger.kernel.org" , "linux-pm@vger.kernel.org" , "mingo@kernel.org" , "rjw@rjwysocki.net" , "vincent.guittot@linaro.org" , "daniel.lezcano@linaro.org" , "preeti@linux.vnet.ibm.com" , Dietmar Eggemann Subject: Re: [RFC PATCH 02/16] sched: Introduce CONFIG_SCHED_ENERGY Message-ID: <20140610100641.GB1581@e103034-lin> References: <1400869003-27769-1-git-send-email-morten.rasmussen@arm.com> <1400869003-27769-3-git-send-email-morten.rasmussen@arm.com> <20140608060316.GA18179@austad.us> <20140609102027.GA29593@e103034-lin> <20140610093943.GA6758@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140610093943.GA6758@twins.programming.kicks-ass.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 10, 2014 at 10:39:43AM +0100, Peter Zijlstra wrote: > On Mon, Jun 09, 2014 at 11:20:27AM +0100, Morten Rasmussen wrote: > > On Sun, Jun 08, 2014 at 07:03:16AM +0100, Henrik Austad wrote: > > > On Fri, May 23, 2014 at 07:16:29PM +0100, Morten Rasmussen wrote: > > > > The Energy-aware scheduler implementation is guarded by > > > > CONFIG_SCHED_ENERGY. > > > > > > > > Signed-off-by: Dietmar Eggemann > > > > Signed-off-by: Morten Rasmussen > > > > --- > > > > arch/arm/Kconfig | 5 +++++ > > > > 1 file changed, 5 insertions(+) > > > > > > > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > > > > index ab438cb..bfc3a85 100644 > > > > --- a/arch/arm/Kconfig > > > > +++ b/arch/arm/Kconfig > > > > > > Is this going to be duplicate for each architecture enabling this? Why > > > not make a kernel/Kconfig.energy and link to that from those > > > architectures using it? > > > > kernel/Kconfig.energy is better I think. > > Well, strictly speaking I'd prefer to not have more sched CONFIG knobs. > > Do we really need to have this CONFIG guarded? How would you like to disable the energy stuff for users for whom latency is everything? I mean, we are adding some extra load/utilization tracking. While I think we should do everything possible to minimize the overhead, I think it is unrealistic to assume that it will be zero. Is a some extra 'if (energy_enabled)' acceptable? I'm open for other suggestions. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/