From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752632AbcIMBFJ (ORCPT ); Mon, 12 Sep 2016 21:05:09 -0400 Received: from mail-pf0-f178.google.com ([209.85.192.178]:35452 "EHLO mail-pf0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750975AbcIMBFH (ORCPT ); Mon, 12 Sep 2016 21:05:07 -0400 Subject: Re: [PATCH 2/4] cpu: expose pm_qos_resume_latency for each cpu To: Ulf Hansson References: <1472114562-2736-1-git-send-email-alex.shi@linaro.org> <1472114562-2736-2-git-send-email-alex.shi@linaro.org> <57C7A597.4050001@linaro.org> Cc: Greg Kroah-Hartman , open list , "linux-pm@vger.kernel.org" , Daniel Lezcano , "Rafael J. Wysocki" From: Alex Shi Message-ID: <57D750BA.6010305@linaro.org> Date: Tue, 13 Sep 2016 09:04:58 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Cc Rafael. On 09/01/2016 05:26 PM, Ulf Hansson wrote: > In general I think the change makes sense, although it's this last > piece here that I wonder about. > > Is it okay that we expose sysfs attributes to userspace that don't > have any effect if they change the values? Perhaps it should be the > responsibility of the menu governor somehow to expose the sysfs nodes > instead? Unless there are some difficulties that prevents us from that > of course. > Hi Ulf, Sorry for response so late. The pm QoS designed to expose this interface in userspace. Root user can change this value and made effect on device sleeping status. That's required. Since this is per device interface, set it on menu governor isn't so good. Regards Alex