From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992588AbXCGVNx (ORCPT ); Wed, 7 Mar 2007 16:13:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992593AbXCGVNx (ORCPT ); Wed, 7 Mar 2007 16:13:53 -0500 Received: from gromalin.logidee.com ([213.91.4.12]:2485 "EHLO gromalin.logidee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992588AbXCGVNw (ORCPT ); Wed, 7 Mar 2007 16:13:52 -0500 Date: Wed, 7 Mar 2007 22:16:59 +0100 From: Stephane Casset To: Thomas Gleixner Cc: Linux Kernel Mailing List , Ingo Molnar Subject: Re: Linux-2.6.21-rc3 : Dynticks and High resolution Timer hanging the system Message-ID: <20070307211659.GA8010@gromalin.logidee.com> References: <45EEB66C.9090901@googlemail.com> <20070307171230.GA21593@elte.hu> <20070307191252.GA6767@gromalin.logidee.com> <1173297130.24738.714.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1173297130.24738.714.camel@localhost.localdomain> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Le Wed, Mar 07, 2007 at 08:52:10PM +0100, Thomas Gleixner ecrivait : > On Wed, 2007-03-07 at 20:12 +0100, Stephane Casset wrote: > > I also tried compiling the kernel without Tickless and without High > > resolution timer, this kernel is working ok and is one of the first > > kernel to suspend and resume from RAM. Congratulations ! ;p > > > > I tried to compile te kernel with only Tickless System or High > > Resolution timer, both hang on boot. > > There should be no difference between compile time and runtime > disabling. Yes, but I wanted to be sure. > > The hang is just after : > > ACPI: PCI Interrupt 0000:00:1f.1[A] -> GSI 18 (level, low) -> IRQ 18 > > ICH5: chipset revision 2 > > ICH5: not 100% native mode: will probe irqs later > > ide0: BM-DMA at 0x2040-0x2047, BIOS settings: hda:DMA, hdb:pio > > ide1: BM-DMA at 0x2048-0x204f, BIOS settings: hdc:DMA, hdd:pio > > > > And I have the message : > > Switched to NOHZ mode on CPU #1 > > or > > Switched to high resolution mode on CPU #1 > > Depending on the option enabled/disabled > > > > What can I do to help find the bug ? > > Can you capture a boot log with highres and/or dynticks enabled ? No, I can handcopy or take a picture of the last page (25 or 50 lines) > Enable CONFIG_SERIAL_8250_CONSOLE and add "console=ttyS0,115200" to the > commandline. Capture the output with minicom on a second box. The system is a laptop without serial port :( > Also please enable CONFIG_MAGIC_SYSRQ and try to send a SysRq-T and a > SysRq-Q to the machine via keyboard or the serial line. When the system hangs, the keyboard is dead :( I just tried clocksource=acpi_pm and the hang disapears... I tested 2.6.21-rc1 which also hangs but not always, when it hangs I tried Sysrq-T and got this, I noted in parenthesis some value when it does'nt hang... SysRq : Show Pending Timers Timer List Version: v0.3 HRTIMER_MAX_CLOCK_BASES: X now at XXXXXXXXXXX nsecs cpu: 0 clock 0: .index: 0 .resolution: 10000000 nsecs / 1ns (when it does'nt hang) .get_time: ktime_get_real .offset: 0 nsecs active timers: clock 1: .index: 1 .resolution: 10000000 nsecs / 1ns (when it does'nt hang) .get_time: ktime_get .offset: 0 nsecs active timers: .expires_next : 9223372036854775807 nsecs (some thing resonneable when not hanging) Almost the same for cpu1 and Tick Device: mode: 1 Clock Event Device: pit max_delta_ns: 27461866 min_delta_ns: 12571 mult: 5124677 shift: 32 mode: 3 next_event: 9223372036854775807 nsecs set_next_event: pit_next_event set_mode: init_pit_timer event_handler: tick_handle_oneshot_broadcast tick_broadcast_mask: 00000001 tick_broadcast_oneshot_mask: 00000000 Tick Device: mode: 1 Clock Event Device: lapic max_delta_ns: 672715459 min_delta_ns: 1202 mult: 53557254 shift: 32 mode: 3 next_event: 84460000000 nsecs set_next_event: lapic_next_event set_mode: lapic_timer_setup event_handler: hrtimer_interrupt Tick Device: mode: 1 Clock Event Device: lapic max_delta_ns: 672715459 min_delta_ns: 1202 mult: 53557254 shift: 32 mode: 3 next_event: 84790000000 nsecs set_next_event: lapic_next_event set_mode: lapic_timer_setup event_handler: hrtimer_interrupt So it seems that the clock source selection is not working properly or the pit (the default clock source right ?) is not correctly initialised... If you need the complete SYSRQ-T trace for 2.6.21-rc1 hanging/not hanging I can provide it but it is quiet long to handwrite it :( A+ -- Stéphane Casset LOGIDÉE sàrl Se faire plaisir d'apprendre 1a, rue Pasteur Tel : +33 388 23 69 77 casset@logidee.com F-67540 OSTWALD Fax : +33 388 23 69 77 http://logidee.com