From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752010AbZFKOC0 (ORCPT ); Thu, 11 Jun 2009 10:02:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751155AbZFKOCT (ORCPT ); Thu, 11 Jun 2009 10:02:19 -0400 Received: from cantor.suse.de ([195.135.220.2]:40662 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750948AbZFKOCS (ORCPT ); Thu, 11 Jun 2009 10:02:18 -0400 Date: Thu, 11 Jun 2009 16:02:20 +0200 Message-ID: From: Takashi Iwai To: David Miller Cc: linux-kernel@vger.kernel.org Subject: Re: sound skipping regression introduced in 2.6.30-rc8 In-Reply-To: <20090611.042848.193715083.davem@davemloft.net> <20090611.050220.179261434.davem@davemloft.net> References: <20090610.112804.193703669.davem@davemloft.net> <20090611.042848.193715083.davem@davemloft.net> User-Agent: Wanderlust/2.12.0 (Your Wildest Dreams) SEMI/1.14.6 (Maruoka) FLIM/1.14.7 (=?ISO-8859-4?Q?Sanj=F2?=) APEL/10.6 Emacs/22.3 (x86_64-suse-linux-gnu) MULE/5.0 (SAKAKI) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org At Thu, 11 Jun 2009 04:28:48 -0700 (PDT), David Miller wrote: > > From: Takashi Iwai > Date: Wed, 10 Jun 2009 21:37:14 +0200 > > > Could you set CONFIG_SND_PCM_XRUN_DEBUG=y and do > > # echo 1 > /proc/asound/card0/pcm0p/xrun_debug > > then check your app? Does it work better, and get any kernel messages? > > Yes, the skipping goes away and I get hw_ptr skipping kernel messages: > > [61581.519051] PCM: hw_ptr skipping! (pos=10240, delta=15368, period=1024, jdelta=0/32) > [61584.420358] PCM: hw_ptr skipping! (pos=2048, delta=16328, period=1024, jdelta=2/34) > [61593.956318] PCM: hw_ptr skipping! (pos=1024, delta=15368, period=1024, jdelta=0/32) > [61596.964300] PCM: hw_ptr skipping! (pos=14336, delta=15368, period=1024, jdelta=0/32) > [61600.036292] PCM: hw_ptr skipping! (pos=14336, delta=15368, period=1024, jdelta=0/32) > [61605.454947] PCM: hw_ptr skipping! (pos=12288, delta=15368, period=1024, jdelta=0/32) OK, then obviously intel8x0 driver gets screwed and is giving bogus position data. At Thu, 11 Jun 2009 05:02:20 -0700 (PDT), David Miller wrote: > > From: Takashi Iwai > Date: Wed, 10 Jun 2009 21:37:14 +0200 > > > Also, it'd be helpful if you can check whether the problem exists in > > the current sound git tree (for-linus branch), too. > > git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6.git for-linus > > Same behavior as 2.6.30, but debugging messages are formatted differently > :-) > > [ 1109.062182] PCM: Lost interrupts? (stream=0, delta=16384, intr_ptr=73728) > [ 1125.126123] PCM: Lost interrupts? (stream=0, delta=16384, intr_ptr=861184) > [ 1131.398094] PCM: Lost interrupts? (stream=0, delta=16384, intr_ptr=1178624) > [ 1135.579406] PCM: Lost interrupts? (stream=0, delta=16384, intr_ptr=1395712) > [ 1145.115367] PCM: Lost interrupts? (stream=0, delta=16384, intr_ptr=1869824) > [ 1152.688670] PCM: Lost interrupts? (stream=0, delta=16384, intr_ptr=2249728) I guess this is because of the change of xrun_debug semantics. Try to set 5 to xrun_debug instead of 1. Then you'll get the similar results like 2.6.30, I guess. (Setting to 4 will run with the sanity check but without debug prints, BTW.) I'll investigate the problem, but probably a bit later as now is a long weekend in Germany... thanks, Takashi