Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262252AbTESSWk (ORCPT ); Mon, 19 May 2003 14:22:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262258AbTESSWk (ORCPT ); Mon, 19 May 2003 14:22:40 -0400 Received: from palrel10.hp.com ([156.153.255.245]:6039 "EHLO palrel10.hp.com") by vger.kernel.org with ESMTP id S262252AbTESSWh (ORCPT ); Mon, 19 May 2003 14:22:37 -0400 From: David Mosberger MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <16073.9205.641605.741130@napali.hpl.hp.com> Date: Mon, 19 May 2003 11:35:33 -0700 To: Arjan van de Ven Cc: davidm@hpl.hp.com, "David S. Miller" , Andrew Morton , Andi Kleen , john stultz , linux-kernel@vger.kernel.org, David Mosberger Subject: Re: time interpolation hooks In-Reply-To: <20030519174203.A7061@devserv.devel.redhat.com> References: <20030516142311.3844ee97.akpm@digeo.com> <16069.24454.349874.198470@napali.hpl.hp.com> <1053139080.7308.6.camel@rth.ninka.net> <16073.5555.158600.61609@napali.hpl.hp.com> <20030519174203.A7061@devserv.devel.redhat.com> X-Mailer: VM 7.07 under Emacs 21.2.1 Reply-To: davidm@hpl.hp.com X-URL: http://www.hpl.hp.com/personal/David_Mosberger/ Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1397 Lines: 34 >>>>> On Mon, 19 May 2003 17:42:03 +0000, Arjan van de Ven said: Arjan> On Mon, May 19, 2003 at 10:34:43AM -0700, David Mosberger wrote: >> struct time_interpolator { >> void (*update_wall_time) (long delta_nsec); >> void (*reset_wall_time) (long delta_nsec); >> unsigned long frequency; /* frequency in counts/second */ >> unsigned long drift; /* drift in parts-per-million (?) */ >> }; Arjan> probably also a "get interpolated value" kind of thing ? Yes, of course. Not a good idea to write an email in a hurry. Arjan> other than that it seems to match what I had in mind. Arjan> For the score we may need something creative; I'm not sure all timers Arjan> have a defined drift, otoh parts-per-million seems to be the Arjan> standard mechanism of reporting this. What could you possibly do about a timer with an unknown drift? Perhaps give preference to higher frequency, even if the drift is unknown? In any case, I suppose we can fine-tune the policy afterwards. Andrew, I assume it's OK with you if I update the ia64 code to the proposed interface and then send you an updated patch? --david - 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/