Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753132Ab1EEI0K (ORCPT ); Thu, 5 May 2011 04:26:10 -0400 Received: from www.linutronix.de ([62.245.132.108]:40767 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751338Ab1EEI0I (ORCPT ); Thu, 5 May 2011 04:26:08 -0400 Date: Thu, 5 May 2011 10:25:46 +0200 (CEST) From: Thomas Gleixner To: john stultz cc: Christian Hoffmann , Linux Kernel Mailing List Subject: Re: Long timeout when booting >= 2.6.38 In-Reply-To: <1304558210.2943.24.camel@work-vm> Message-ID: References: <4DBEFCBA.3070501@christianhoffmann.info> <1304363375.3226.5.camel@work-vm> <4DBF1725.3030800@christianhoffmann.info> <1304372955.3226.15.camel@work-vm> <4DBF2FB4.8000304@christianhoffmann.info> <1304470839.3037.12.camel@work-vm> <4DC100D0.1030302@christianhoffmann.info> <1304558210.2943.24.camel@work-vm> User-Agent: Alpine 2.02 (LFD 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2282 Lines: 63 On Wed, 4 May 2011, john stultz wrote: > On Wed, 2011-05-04 at 09:31 +0200, Christian Hoffmann wrote: > > In fact, switching to acpi_pm doesn't seem to work: > > > > $ dmesg | grep clock > > > > [ 0.000000] Command line: BOOT_IMAGE=/vmlinuz-2.6.39-rc5-ch-broken+ > > root=/dev/mapper/vg-root ro quiet splash vt.handoff=7 clocksource=acpi_pm > > [ 0.000000] Kernel command line: > > BOOT_IMAGE=/vmlinuz-2.6.39-rc5-ch-broken+ root=/dev/mapper/vg-root ro > > quiet splash vt.handoff=7 clocksource=acpi_pm > > [ 0.000000] hpet clockevent registered > > [ 1.413835] Switching to clocksource hpet > > [ 1.420762] Override clocksource acpi_pm is not HRT compatible. > > Cannot switch while in HRT/NOHZ mode > > [ 147.940143] Refined TSC clocksource calibration: 2809.409 MHz. > > [ 147.940147] Switching to clocksource tsc > > So I think I've sorted this out. > > The watchdog code is what enables CLOCK_SOURCE_VALID_FOR_HRES, but we > actually end up selecting the clocksource before we enqueue it into the > watchdog list, so that's why we see the warning. > > I suspect the following will resolve this detail. It does. Good catch! > Signed-off-by: John Stultz > > diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c > index 6519cf6..0e17c10 100644 > --- a/kernel/time/clocksource.c > +++ b/kernel/time/clocksource.c > @@ -685,8 +685,8 @@ int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq) > /* Add clocksource to the clcoksource list */ > mutex_lock(&clocksource_mutex); > clocksource_enqueue(cs); > - clocksource_select(); > clocksource_enqueue_watchdog(cs); > + clocksource_select(); > mutex_unlock(&clocksource_mutex); > return 0; > } > @@ -706,8 +706,8 @@ int clocksource_register(struct clocksource *cs) > > mutex_lock(&clocksource_mutex); > clocksource_enqueue(cs); > - clocksource_select(); > clocksource_enqueue_watchdog(cs); > + clocksource_select(); > mutex_unlock(&clocksource_mutex); > return 0; > } > > > -- 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/