From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= Subject: Re: [PATCH 33/35] hack: Don't disable underrun reporting on the first error on ILK/SNB/IVB Date: Fri, 5 Jul 2013 20:34:12 +0300 Message-ID: <20130705173412.GG5004@intel.com> References: <1373014667-19484-1-git-send-email-ville.syrjala@linux.intel.com> <1373014667-19484-34-git-send-email-ville.syrjala@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Received: from mga03.intel.com (mga03.intel.com [143.182.124.21]) by gabe.freedesktop.org (Postfix) with ESMTP id EF72DE5CC2 for ; Fri, 5 Jul 2013 10:34:15 -0700 (PDT) Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Paulo Zanoni Cc: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Fri, Jul 05, 2013 at 02:19:22PM -0300, Paulo Zanoni wrote: > 2013/7/5 : > > From: Ville Syrj=E4l=E4 > > > > Don't want to lose them in the noise. Just let them happen. > = > When I was experimenting with this, I noticed that when we get > underruns, we get thousands of underruns per second, until we fix the > condition that is causing the underruns. With this we'll get tons and > tons and tons of interrupts and really flood dmesg. Yeah. It was just a hack to see if the code managed to apply the watermarks in time before the pipe really starts to demand pixels. If you actually configure the system so that it constantly underruns (something we shouldn't allow, but currently we do) your dmesg will be full of this stuff. Clearly we can't even being to consider merging a patch like this before we have much stricter checks to prevent such mode/plane configurations. I guess even then some ratelimiting might be a good idea, just in case. -- = Ville Syrj=E4l=E4 Intel OTC