From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Ornati Subject: Re: [Intel-gfx] Interrupt latency on some 945GM platforms Date: Sat, 25 Sep 2010 12:28:20 +0200 Message-ID: <20100925122820.37c01ea3@gmail.com> References: <201009132336.17310.anarsoul@gmail.com> <201009171002.09187.simon.farnsworth@onelan.co.uk> <4b4d1e0a-b1ad-40f1-a829-6d4726d2b2d3@email.android.com> <201009171550.48480.anarsoul@gmail.com> <20100921202607.2b46ffca@gmail.com> <20100921155653.440afea4@jbarnes-desktop> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20100921155653.440afea4@jbarnes-desktop> Sender: linux-kernel-owner@vger.kernel.org To: Jesse Barnes Cc: Vasily Khoruzhick , Simon Farnsworth , intel-gfx@lists.freedesktop.org, Sitsofe Wheeler , Venkatesh Pallipadi , Thomas Gleixner , linux-kernel@vger.kernel.org List-Id: intel-gfx@lists.freedesktop.org On Tue, 21 Sep 2010 15:56:53 -0700 Jesse Barnes wrote: > > I've a laptop with 945GM (Asus x5dij) and with 2.6.32+ kernels I'm > > having random, but not frequent, screen flickering problems (for some > > reasons 2.6.31 works fine). > > > > Problem goes away with "nohz=off". > > > > I'll try with "processor.max_cstate=?" and see if that works too. > > Can you guys try something like this? My theory is that 945GM has some > power management behavior we're failing to configure correctly. If > disabling it works, then it's likely related. UPDATE: "processor.max_cstate=2" doesn't solve the sporadic flicker problem. The patch, applied on top of 2.6.35.4, freezes the laptop on boot. Summary: nohz=off good processor.max_cstate=1 good processor.max_cstate=2 bad Bye, -- Paolo Ornati Linux 2.6.35.4 on x86_64