From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757481AbZCAPos (ORCPT ); Sun, 1 Mar 2009 10:44:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755381AbZCAPoj (ORCPT ); Sun, 1 Mar 2009 10:44:39 -0500 Received: from silver.sucs.swan.ac.uk ([137.44.10.1]:43749 "EHLO silver.sucs.swan.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753601AbZCAPoi (ORCPT ); Sun, 1 Mar 2009 10:44:38 -0500 Date: Sun, 1 Mar 2009 15:44:33 +0000 From: Sitsofe Wheeler To: Jesper Krogh Cc: Linus Torvalds , Linux Kernel Mailing List Subject: Re: Linux 2.6.29-rc6 (clocksource) Message-ID: <20090301154433.GA25246@silver.sucs.org> References: <49A6F39F.9040801@krogh.cc> <49AAA50F.5070209@krogh.cc> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <49AAA50F.5070209@krogh.cc> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Mar 01, 2009 at 04:09:03PM +0100, Jesper Krogh wrote: > Jesper Krogh wrote: > >The "current_clocsource" is the same on both systems. > > > >$ cat /sys/devices/system/clocksource/clocksource0/current_clocksource > >tsc > > What selects the "current_clocksource"? I tried to boot one of the > kernels hat have the problem on another piece of hardware and on that > system it ended up defaulting to "acpi_pm" instead of "tsc". I believe different clock sources have different priorities based on their resolution and behaviour. Clock sources's that "go bad" because hardware interactions are hopefully detected and subsequent "best" clock sources are then tried. There was a nice treatment of different clocksourcs in this kernelnewbies thread: http://www.mail-archive.com/kernelnewbies@nl.linux.org/msg05164.html . -- Sitsofe | http://sucs.org/~sits/