From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Lezcano Subject: Re: [RFC PATCH] cpuidle: allow per cpu latencies Date: Thu, 19 Apr 2012 11:14:27 +0200 Message-ID: <4F8FD773.5030500@linaro.org> References: <1333619620-21201-1-git-send-email-pdeschrijver@nvidia.com> <4F7DA009.4010802@linux.intel.com> <4F7F0D52.8080305@linaro.org> <20120410102857.GA22721@tbergstrom-lnx.Nvidia.com> <20120416153456.GB514@tbergstrom-lnx.Nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; Format="flowed" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20120416153456.GB514@tbergstrom-lnx.Nvidia.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Peter De Schrijver Cc: Kevin Hilman , Len Brown , Trinabh Gupta , Russell King , Stephen Warren , "linux-kernel@vger.kernel.org" , Deepthi Dharwar , Olof Johansson , "Shilimkar, Santosh" , Colin Cross , "linux-tegra@vger.kernel.org" , Rob Lee , Arjan van de Ven , "linux-arm-kernel@lists.infradead.org" , Ricardo Salveti List-Id: linux-tegra@vger.kernel.org T24gMDQvMTYvMjAxMiAwNTozNCBQTSwgUGV0ZXIgRGUgU2NocmlqdmVyIHdyb3RlOgo+Pgo+PiBN YXliZSB3ZSBhbHNvIHdhbnQgdG8gbWFrZSB0aGUgJ2Rpc2FibGVkJyBmbGFnIHBlciBDUFUgdGhl biBvciBwcm92aWRlIHNvbWUKPj4gb3RoZXIgd2F5IHRoZSBudW1iZXIgb2YgQyBzdGF0ZXMgY2Fu IGJlIGRpZmZlcmVudCBwZXIgQ1BVPwo+Cj4gV2hhdCBkbyB5b3UgdGhpbmsgYWJvdXQgdGhpcz8g RG8gd2UgYWxzbyB3YW50IHRvIG1ha2UgdGhlIGRpc2FibGVkIGZsYWcgcGVyCj4gQ1BVPyBPciBo b3cgc2hvdWxkIHdlIGRlYWwgd2l0aCBhIGRpZmZlcmVudCBudW1iZXIgb2YgQyBzdGF0ZXMgcGVy IENQVT8KCkhpIFBldGVyLAoKeWVzLCB0aGF0IGNvdWxkIG1ha2VzIHNlbnNlLiBCdXQgaW4gbW9z dCBvZiB0aGUgYXJjaGl0ZWN0dXJlLCB0aGlzIGlzIApub3QgbmVlZGVkLCBzbyBkdXBsaWNhdGlu ZyB0aGUgc3RhdGUncyBhcnJheSBhbmQgbGF0ZW5jaWVzIGlzIHVubmVlZGVkIAptZW1vcnkgY29u c3VtcHRpb24uCgpNYXliZSB3ZSBjYW4gbG9vayBmb3IgYSBDT1cgYXBwcm9hY2gsIHNpbWlsYXIg dG8gd2hhdCBpcyBkb25lIGZvciB0aGUgCm5zcHJveHkgc3RydWN0dXJlLCBubyA/CgoKCi0tIAog IDxodHRwOi8vd3d3LmxpbmFyby5vcmcvPiBMaW5hcm8ub3JnIOKUgiBPcGVuIHNvdXJjZSBzb2Z0 d2FyZSBmb3IgQVJNIFNvQ3MKCkZvbGxvdyBMaW5hcm86ICA8aHR0cDovL3d3dy5mYWNlYm9vay5j b20vcGFnZXMvTGluYXJvPiBGYWNlYm9vayB8CjxodHRwOi8vdHdpdHRlci5jb20vIyEvbGluYXJv b3JnPiBUd2l0dGVyIHwKPGh0dHA6Ly93d3cubGluYXJvLm9yZy9saW5hcm8tYmxvZy8+IEJsb2cK CgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwpsaW51eC1h cm0ta2VybmVsIG1haWxpbmcgbGlzdApsaW51eC1hcm0ta2VybmVsQGxpc3RzLmluZnJhZGVhZC5v cmcKaHR0cDovL2xpc3RzLmluZnJhZGVhZC5vcmcvbWFpbG1hbi9saXN0aW5mby9saW51eC1hcm0t a2VybmVsCg== From mboxrd@z Thu Jan 1 00:00:00 1970 From: daniel.lezcano@linaro.org (Daniel Lezcano) Date: Thu, 19 Apr 2012 11:14:27 +0200 Subject: [RFC PATCH] cpuidle: allow per cpu latencies In-Reply-To: <20120416153456.GB514@tbergstrom-lnx.Nvidia.com> References: <1333619620-21201-1-git-send-email-pdeschrijver@nvidia.com> <4F7DA009.4010802@linux.intel.com> <4F7F0D52.8080305@linaro.org> <20120410102857.GA22721@tbergstrom-lnx.Nvidia.com> <20120416153456.GB514@tbergstrom-lnx.Nvidia.com> Message-ID: <4F8FD773.5030500@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 04/16/2012 05:34 PM, Peter De Schrijver wrote: >> >> Maybe we also want to make the 'disabled' flag per CPU then or provide some >> other way the number of C states can be different per CPU? > > What do you think about this? Do we also want to make the disabled flag per > CPU? Or how should we deal with a different number of C states per CPU? Hi Peter, yes, that could makes sense. But in most of the architecture, this is not needed, so duplicating the state's array and latencies is unneeded memory consumption. Maybe we can look for a COW approach, similar to what is done for the nsproxy structure, no ? -- Linaro.org ? Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753464Ab2DSJOo (ORCPT ); Thu, 19 Apr 2012 05:14:44 -0400 Received: from mail-bk0-f46.google.com ([209.85.214.46]:34040 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751245Ab2DSJOl (ORCPT ); Thu, 19 Apr 2012 05:14:41 -0400 Message-ID: <4F8FD773.5030500@linaro.org> Date: Thu, 19 Apr 2012 11:14:27 +0200 From: Daniel Lezcano User-Agent: Mozilla/5.0 (X11; Linux i686; rv:10.0.2) Gecko/20120216 Thunderbird/10.0.2 MIME-Version: 1.0 To: Peter De Schrijver CC: "Shilimkar, Santosh" , Kevin Hilman , Len Brown , Trinabh Gupta , Russell King , Stephen Warren , "linux-kernel@vger.kernel.org" , Deepthi Dharwar , "linux-tegra@vger.kernel.org" , Colin Cross , Olof Johansson , "linux-arm-kernel@lists.infradead.org" , Arjan van de Ven , Rob Lee , Ricardo Salveti Subject: Re: [RFC PATCH] cpuidle: allow per cpu latencies References: <1333619620-21201-1-git-send-email-pdeschrijver@nvidia.com> <4F7DA009.4010802@linux.intel.com> <4F7F0D52.8080305@linaro.org> <20120410102857.GA22721@tbergstrom-lnx.Nvidia.com> <20120416153456.GB514@tbergstrom-lnx.Nvidia.com> In-Reply-To: <20120416153456.GB514@tbergstrom-lnx.Nvidia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/16/2012 05:34 PM, Peter De Schrijver wrote: >> >> Maybe we also want to make the 'disabled' flag per CPU then or provide some >> other way the number of C states can be different per CPU? > > What do you think about this? Do we also want to make the disabled flag per > CPU? Or how should we deal with a different number of C states per CPU? Hi Peter, yes, that could makes sense. But in most of the architecture, this is not needed, so duplicating the state's array and latencies is unneeded memory consumption. Maybe we can look for a COW approach, similar to what is done for the nsproxy structure, no ? -- Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog