From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Subject: Re: [linux-pm] [PATCH V3] cpuidle: Add a sysfs entry to disable specific C state for debug purpose. Date: Tue, 13 Mar 2012 19:46:19 -0700 Message-ID: <20120314024619.GC22955@kroah.com> References: <1330998885.1916.89.camel@ymzhang> <20120306052236.GA19416@kroah.com> <1331013078.1916.103.camel@ymzhang> <20120306143935.GA23346@kroah.com> <20120312181151.GE14020@sirena.org.uk> <20120312192936.GC24873@kroah.com> <1331602594.1916.155.camel@ymzhang> <20120313192949.GA8568@kroah.com> <1331686500.1916.172.camel@ymzhang> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1331686500.1916.172.camel@ymzhang> Sender: linux-kernel-owner@vger.kernel.org To: Yanmin Zhang Cc: Mark Brown , "Brown, Len" , ShuoX Liu , Ingo Molnar , "linux-kernel@vger.kernel.org" , Henrique de Moraes Holschuh , "H. Peter Anvin" , andi.kleen@intel.com, Thomas Gleixner , "linux-pm@lists.linux-foundation.org" , Andrew Morton List-Id: linux-pm@vger.kernel.org On Wed, Mar 14, 2012 at 08:55:00AM +0800, Yanmin Zhang wrote: > On Tue, 2012-03-13 at 12:29 -0700, Greg KH wrote: > > On Tue, Mar 13, 2012 at 09:36:34AM +0800, Yanmin Zhang wrote: > > > On Mon, 2012-03-12 at 12:29 -0700, Greg KH wrote: > > > > On Mon, Mar 12, 2012 at 06:11:51PM +0000, Mark Brown wrote: > > > > > On Tue, Mar 06, 2012 at 06:39:35AM -0800, Greg KH wrote: > > > > > > > > > > > Do you know of any tools using these files? I have never heard of them, > > > > > > and I was told we should move these files years ago. So I don't think > > > > > > there should be any api issues. > > > > > > > > > > powertop uses them. > > > > > > > > Ok, then we can't move them all. > > > > > > > > We should then just move the ones that have multiple lines, as I'm > > > > pretty sure powertop doesn't use them, right? > > > All sys files under cpu/cpuXXX/cpuidle have single line. If we move > > > some files to debugfs and keep others under sysfs, users might be confused. > > > > > > Should we go back to the 1st version which just adds the new entry to > > > sysfs? > > > > Wait, I thought this whole thing started when we wanted to move the > > files that had multiple lines out of sysfs? > No. Liu Shuo's patch adds a new entry under cpu/cpuXXX/cpuidle and users > can disable specific C state. > A gentleman raised that if we should move it to debugfs, then you suggested > to move all files under cpu/cpuXXX/cpuidle to debugfs. > > > > > If none of these do, and they all are being used by tools already, then > > fine, they should stay. > Agree. > > > > > But for some reason, I thought there was a problem here. Perhaps that > > was in the cpufreq code? > I checked cpufreq quickly. Every file has single-line, but some have > multiple-fields. > > We would send a new patch based on sysfs as the new entry has > single line. Then that's fine, I'm very sorry for getting this wrong the first time and causing you extra work. I owe you all the drink of your choice the next time I see you. greg k-h