From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Lezcano Subject: Re: [PATCH V6] powercap/drivers/idle_injection: Add an idle injection framework Date: Wed, 13 Jun 2018 22:00:39 +0200 Message-ID: <0b72e862-6bbe-e706-79f8-e1b690982920@linaro.org> References: <1528804816-32636-1-git-send-email-daniel.lezcano@linaro.org> <1528905257.48473.4.camel@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <1528905257.48473.4.camel@intel.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: "Pandruvada, Srinivas" , "viresh.kumar@linaro.org" , "rjw@rjwysocki.net" Cc: "linux-kernel@vger.kernel.org" , "peterz@infradead.org" , "Zhang, Rui" , "edubezval@gmail.com" , "linux-pm@vger.kernel.org" , "andrea.parri@amarulasolutions.com" , "kevin.wangtao@linaro.org" , "leo.yan@linaro.org" , "daniel.thompson@linaro.org" , "javi.merino@kernel.org" , "vincent.guittot@linaro.org" List-Id: linux-pm@vger.kernel.org On 13/06/2018 17:54, Pandruvada, Srinivas wrote: > On Tue, 2018-06-12 at 14:00 +0200, Daniel Lezcano wrote: >> Initially, the cpu_cooling device for ARM was changed by adding a new >> policy inserting idle cycles. The intel_powerclamp driver does a >> similar action. >> >> Instead of implementing idle injections privately in the cpu_cooling >> device, move the idle injection code in a dedicated framework and >> give >> the opportunity to other frameworks to make use of it. >> >> The framework relies on the smpboot kthreads which handles via its >> main loop the common code for hotplugging and [un]parking. >> >> This code was previously tested with the cpu cooling device and went >> through several iterations. It results now in split code and API >> exported in the header file. It was tested with the cpu cooling >> device >> with success. >> > May be I have missed, but I don't see any use of powercap sysfs. > > We created powercap sys that user space is presented a common interface > for power capping. The RAPL driver was also submitted as cooling device > before, but suggestion was to create this powercap. > > So if powercap interface is not enough then may be we should enhance > that. We are creating a framework for idle injection. This framework can then be used by the cpu_cooling device, the power_clamp and in addition a power capping for ARM (if it makes sense). -- Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog