From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arjan van de Ven Subject: Re: [Bug #12152] Huge wakeups number from i1915 Date: Sun, 7 Dec 2008 15:12:03 -0800 Message-ID: <20081207151203.46c01a0d@infradead.org> References: <6VnlupFpCsN.A.2rE.MsEPJB@chimera> <07Xes05z25M.A.VtF.ksEPJB@chimera> <20081207145203.0f998d5b@infradead.org> <200812072352.07151.rjw@sisk.pl> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <200812072352.07151.rjw-KKrjLPT3xs0@public.gmane.org> Sender: kernel-testers-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: "Rafael J. Wysocki" Cc: Linux Kernel Mailing List , Kernel Testers List , Yves-Alexis Perez On Sun, 7 Dec 2008 23:52:06 +0100 "Rafael J. Wysocki" wrote: > On Sunday, 7 of December 2008, Arjan van de Ven wrote: > > On Sun, 7 Dec 2008 21:32:54 +0100 (CET) > > "Rafael J. Wysocki" wrote: > > > > > This message has been generated automatically as a part of a > > > report of recent regressions. > > > > > > The following bug entry is on the current list of known > > > regressions from 2.6.27. Please verify if it still should be > > > listed and let me know (either way). > > > > > > > > > Bug-Entry : > > > http://bugzilla.kernel.org/show_bug.cgi?id=12152 > > > Subject : Huge wakeups number from i1915 > > > Submitter : Yves-Alexis Perez > > > Date : 2008-12-02 16:48 (6 days old) > > > References : > > > http://marc.info/?l=linux-acpi&m=122823656702994&w=4 > > > > > > > at least in some of the cases where this has been seen the cause is > > the following: > > The i915 DRM driver used to do polling for completion, busy > > waiting. It moved to be interrupt driven, which is usually better > > for power, but it will show up as more wakeups in powertop.... > > IOW, this is not a regression? I don't know about this specifc case (not enough information) but for the case I described it's not a regression. Going to interrupt driven from busy waiting is an improvement not a regression :) -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org