Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932663AbWJLQL7 (ORCPT ); Thu, 12 Oct 2006 12:11:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932665AbWJLQL6 (ORCPT ); Thu, 12 Oct 2006 12:11:58 -0400 Received: from mustang.oldcity.dca.net ([216.158.38.3]:49351 "HELO mustang.oldcity.dca.net") by vger.kernel.org with SMTP id S932663AbWJLQL5 (ORCPT ); Thu, 12 Oct 2006 12:11:57 -0400 Subject: Re: Keyboard Stuttering From: Lee Revell To: john stultz Cc: Dmitry Torokhov , Frank Sorenson , linux-kernel@vger.kernel.org, David Gerber In-Reply-To: <1160504714.4973.6.camel@localhost> References: <200610061218.36883.dg-lkml@zapek.com> <1160504714.4973.6.camel@localhost> Content-Type: text/plain Date: Thu, 12 Oct 2006 12:12:44 -0400 Message-Id: <1160669564.24931.37.camel@mindpipe> Mime-Version: 1.0 X-Mailer: Evolution 2.6.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1455 Lines: 36 On Tue, 2006-10-10 at 11:25 -0700, john stultz wrote: > On Tue, 2006-10-10 at 13:09 -0400, Dmitry Torokhov wrote: > > > Same problem here. Intel Core 2 Duo with 2.6.19-rc1 x86_64 SMP. Happens on > > > 2.6.17 too. I use 'noapic' as a workaround but that disables one of the CPU > > > core of course. > > > > > > I cannot reproduce the problem within the console nor gdm. Only on the X > > > desktop. > > > > > > > John, > > > > It looks like the only clocksource available on David's box is > > "jiffies" although the processor shows that it supporst tsc and PM > > timer is enabled and I think that this is what causes keyboard > > stuttering in X. See http://bugzilla.kernel.org/show_bug.cgi?id=7291. > > I believe clocksources is your turf, could you please take a look at > > this. > > Sure thing. I followed up in the bug, but I don't think the clocksource > code is involved. x86_64 hasn't converted to GENERIC_TIME, so jiffies is > what we use to increment xtime, but the TSC, ACPI PM, or HPET is used > for gettimeofday, etc. > > I suspect C3 idling is the culprit, since noapic works around the issue. Wait, does this mean that Intel's x86-64 implementation has the same buggy TSC as AMD's? Lee - 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/