From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762686AbYDSVbz (ORCPT ); Sat, 19 Apr 2008 17:31:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753415AbYDSVbs (ORCPT ); Sat, 19 Apr 2008 17:31:48 -0400 Received: from proxy2.bredband.net ([195.54.101.72]:55937 "EHLO proxy2.bredband.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753193AbYDSVbr (ORCPT ); Sat, 19 Apr 2008 17:31:47 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AiI8AK4BCkhT48OPPGdsb2JhbACBYI97AQEBATCYNQ Message-ID: <480A64B9.2080307@coderworld.net> Date: Sat, 19 Apr 2008 23:31:37 +0200 From: Richard Jonsson User-Agent: Thunderbird 2.0.0.12 (X11/20080227) MIME-Version: 1.0 To: Frans Pop CC: linux-kernel@vger.kernel.org, Dhaval Giani , "Rafael J. Wysocki" , Ingo Molnar , Srivatsa Vaddagiri , Peter Zijlstra Subject: Re: [rc8] Regression: key repeats and skips in music during compilation References: <200804041222.35025.elendil@planet.nl> <200804071229.27113.rjw@sisk.pl> <20080407112459.GA11532@linux.vnet.ibm.com> <200804071403.59500.elendil@planet.nl> <48009D04.3000509@coderworld.net> In-Reply-To: <48009D04.3000509@coderworld.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Richard Jonsson skrev: > Frans Pop skrev: >> On Monday 07 April 2008, Dhaval Giani wrote: >>> On Mon, Apr 07, 2008 at 12:29:26PM +0200, Rafael J. Wysocki wrote: >>>> On Monday, 7 of April 2008, Frans Pop wrote: >>>>> On Monday 07 April 2008, Rafael J. Wysocki wrote: >>>>>> On Sunday, 6 of April 2008, Rafael J. Wysocki wrote: >>>>>>> On Friday, 4 of April 2008, Frans Pop wrote: >>>>>>>> While compiling glibc I am getting frequent short skips in >>>>>>>> music play anddddddddddddddddd I have now three times seen key >>>>>>>> repeats (as in this sentence). When there is a skip in the >>>>>>>> music, there is also a delay in characters being typed >>>>>>>> appearing on the screen. >>>>>>> Can you test with CONFIG_GROUP_SCHED unset, please? >>>>>> I was able to reproduce this issue with -rc8 on one of my test >>>>>> systems, >>>>> In the mean time I have verified that the issue also existed in rc6, >>>>> so it's not a recent regression. >>>>> >>>>>> but I'm not any more with the current Linus' tree and >>>>>> CONFIG_GROUP_SCHED unset, FWIW. >>>>> Hmm. Does that mean that you _can_ reproduce it with git HEAD and >>>>> CONFIG_GROUP_SCHED set? That would mean it is still an issue in HEAD >>>>> and group scheduling is the culprit. >>>> Well, CONFIG_GROUP_SCHED is known to cause problems, AFAICS, and some >>>> fixes are scheduled for the 2.6.26 time frame. >>> I thought we had most of the issues ironed out. >> >> Note that I can also reproduce the issue with a kernel that does *not* >> have CONFIG_GROUP_SCHED set. I still get the music skips (maybe less >> frequently, but that's hard to measure), and I've have also seen key >> repeats once. >> >> Anything I can do to provide additional info on this? >> >> Cheers, >> FJP >> >> # CONFIG_CGROUPS is not set >> # CONFIG_GROUP_SCHED is not set >> (config otherwise identical to my initial mail) >> -- >> To unsubscribe from this list: send the line "unsubscribe >> linux-kernel" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> Please read the FAQ at http://www.tux.org/lkml/ > > Hi > > I reported about this problem a while back [1], and have been busy > bisecting. I have verified the issue in v2.6.25-rc6 and I'm about 99% > certain that the issue is not present in v2.6.25-rc5-300-gb663c6f. > > I've been running this kernel for 3 days now with no problems. > > It's a bit worrying to me that it's more frequent in builds between rc6 > and rc7 than vanilla rc6. Newer builds than rc7 not tested. > > I've not noticed stuttering audio, but at one time I saw stuttering > video in a way I don't normally see. May be incidence. > > Maybe relevant config: > # CONFIG_CGROUPS is not set > CONFIG_GROUP_SCHED=y > CONFIG_FAIR_GROUP_SCHED=y > # CONFIG_RT_GROUP_SCHED is not set > # CONFIG_CGROUP_SCHED is not set > > [1]: http://lkml.org/lkml/2008/3/29/96 Bisecting this bug is very inefficient, but I've managed to narrow it down a bit more. The log so far: git-bisect start # good: [b663c6fd98c9cf586279db03cec3257c413efd00] nfsd: fix oops on access from high-numbered ports git-bisect good b663c6fd98c9cf586279db03cec3257c413efd00 # bad: [a978b30af3bab0dd9af9350eeda25e76123fa28e] Linux 2.6.25-rc6 git-bisect bad a978b30af3bab0dd9af9350eeda25e76123fa28e # bad: [afbf331ed1252c85753ac6790356c11e171f3d0b] Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 git-bisect bad afbf331ed1252c85753ac6790356c11e171f3d0b # good: [bde1709aaa98f5004ab1580842c422be18eb4bc3] firewire: fw-ohci: use dma_alloc_coherent for ar_buffer git-bisect good bde1709aaa98f5004ab1580842c422be18eb4bc3 This leaves these commits according to 'git bisect visualize': [NET]: Fix tbench regression in 2.6.25-rc1 sched: simplify sched_slice() sched: fix fair sleepers sched: fix overload performance: buddy wakeups sched: fix calc_delta_mine() sched: fix update_load_add()/sub() <-- currently bisecting, seems to be fine sched: min_vruntime fix sched: fix race in schedule() Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 firewire: fw-ohci: shut up false compiler warning on PPC32 [SCTP]: Fix local_addr deletions during list traversals. Hope this helps / Richard