Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753621AbXFVGXT (ORCPT ); Fri, 22 Jun 2007 02:23:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751282AbXFVGXJ (ORCPT ); Fri, 22 Jun 2007 02:23:09 -0400 Received: from pythia.bakeyournoodle.com ([203.82.209.197]:54693 "EHLO pythia.bakeyournoodle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750769AbXFVGXI (ORCPT ); Fri, 22 Jun 2007 02:23:08 -0400 Date: Fri, 22 Jun 2007 16:23:05 +1000 To: Daniel Walker Cc: Thomas Gleixner , LKML , Andrew Morton , Ingo Molnar , john stultz , LinuxPPC-dev Subject: Re: [RFC] clocksouce implementation for powerpc Message-ID: <20070622062305.GX9768@bakeyournoodle.com> References: <20070616101126.296384219@inhelltoy.tec.linutronix.de> <20070616101637.107940593@inhelltoy.tec.linutronix.de> <1182009083.11539.369.camel@imap.mvista.com> <20070620065710.GR9768@bakeyournoodle.com> <1182351439.18168.79.camel@imap.mvista.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1182351439.18168.79.camel@imap.mvista.com> User-Agent: Mutt/1.5.13 (2006-08-11) From: tony@bakeyournoodle.com (Tony Breeds) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1672 Lines: 42 On Wed, Jun 20, 2007 at 07:57:19AM -0700, Daniel Walker wrote: Hi Daniel. > As I said in our private thread, I do think you should be using > update_vsyscall() .. update_vsyscall() is just called when the time is > set, usually that happens in the timer interrupt and sometimes that > happens in settimeofday() .. Well I've taken another look at the code and I think I can probably restructure my code to use update_vsyscall(). I thought I needed a hook that was called /only/ from settimeofday() (which as you say doesn't match update_vsyscall()'s usage). I'll try again and see what problems I hit. > At least some of your code is duplications over what is already being > worked on inside the powerpc community.. For instance, I know there is > already a timebase clocksource, > > http://people.redhat.com/~mingo/realtime-preempt/patch-2.6.21.5-rt17 Thanks. The one in -rt doesn't seem to support the VDSO. however I see that there is duplication of effort there. > Hmm .. This doesn't look like it's taking into account that the time has > changed .. Your time has effectively incremented by one jiffie .. The > vdso_data doesn't appear to be updated .. Unless I miss your meaning, the vdso is updated in timer_recalc_offset()/update_gtod() when needed. Yours Tony linux.conf.au http://linux.conf.au/ || http://lca2008.linux.org.au/ Jan 28 - Feb 02 2008 The Australian Linux Technical Conference! - 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/