Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261928AbVEPWDM (ORCPT ); Mon, 16 May 2005 18:03:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261935AbVEPV7Z (ORCPT ); Mon, 16 May 2005 17:59:25 -0400 Received: from omx2-ext.sgi.com ([192.48.171.19]:6879 "EHLO omx2.sgi.com") by vger.kernel.org with ESMTP id S261896AbVEPV4h (ORCPT ); Mon, 16 May 2005 17:56:37 -0400 Date: Mon, 16 May 2005 14:53:00 -0700 (PDT) From: Christoph Lameter To: john stultz cc: David Mosberger , lkml , Tim Schmielau , George Anzinger , albert@users.sourceforge.net, Ulrich Windl , Dominik Brodowski , Andi Kleen , paulus@samba.org, schwidefsky@de.ibm.com, keith maanthey , Chris McDermott , Max Asbock , mahuja@us.ibm.com, Nishanth Aravamudan , Darren Hart , "Darrick J. Wong" , Anton Blanchard , donf@us.ibm.com, mpm@selenic.com, benh@kernel.crashing.org, linux-ia64@vger.kernel.org Subject: Re: IA64 implementation of timesource for new time of day subsystem In-Reply-To: <1116279338.13867.30.camel@cog.beaverton.ibm.com> Message-ID: References: <1116029796.26454.2.camel@cog.beaverton.ibm.com> <1116029872.26454.4.camel@cog.beaverton.ibm.com> <1116029971.26454.7.camel@cog.beaverton.ibm.com> <1116030058.26454.10.camel@cog.beaverton.ibm.com> <1116030139.26454.13.camel@cog.beaverton.ibm.com> <1116264858.26990.39.camel@cog.beaverton.ibm.com> <1116269136.26990.67.camel@cog.beaverton.ibm.com> <17032.62615.750699.18847@napali.hpl.hp.com> <1116273055.13867.5.camel@cog.beaverton.ibm.com> <1116276824.13867.15.camel@cog.beaverton.ibm.com> <17033.2445.545597.210557@napali.hpl.hp.com> <1116279338.13867.30.camel@cog.beaverton.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1291 Lines: 29 On Mon, 16 May 2005, john stultz wrote: > Since its possible to do jitter compensation within the itc timesource > driver (and within the fastcall code to preserve the existing > performance), would it be reasonable to deffer making the jitter > compensation code generic until another timesource needs it? It should > be a fairly simple change. Well looks that we will start out with the new time subsystem by putting some hacks in. I need to check in the funky routine (for setting up the fastcall configuration) if the function pointer passed == jitter-compensated-itc and depending on that set a special flag that makes the asm code do jitter compensation. > Or is this just something I'm being hard-headed about? Looks like it. Its not that difficult. Add a jitter compensation flag to timesource. Check on retrieving from a timesource if its less than last if flag is set. Pass the field to the funky function to setup the vsyscalls. Maybe add a general flags field? There may be other things that need to be added in the future. - 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/