From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264297AbUHBXhD (ORCPT ); Mon, 2 Aug 2004 19:37:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264389AbUHBXgq (ORCPT ); Mon, 2 Aug 2004 19:36:46 -0400 Received: from zero.aec.at ([193.170.194.10]:65036 "EHLO zero.aec.at") by vger.kernel.org with ESMTP id S264297AbUHBXfs (ORCPT ); Mon, 2 Aug 2004 19:35:48 -0400 To: Alan Cox cc: linux-kernel@vger.kernel.org Subject: Re: Initial bits to help pull jiffies out of drivers References: <2mGr0-7w6-27@gated-at.bofh.it> From: Andi Kleen Date: Tue, 03 Aug 2004 01:35:44 +0200 In-Reply-To: <2mGr0-7w6-27@gated-at.bofh.it> (Alan Cox's message of "Tue, 27 Jul 2004 22:10:10 +0200") Message-ID: User-Agent: Gnus/5.110003 (No Gnus v0.3) Emacs/21.2 (gnu/linux) 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 Alan Cox writes: > This is really for comment, the basic idea is to add some relative > timer functionality. This gives us timeout objects as well as pulling > jiffies use into one place in the timer code. The need for the old > interfaces never goes away however because some code uses a previous > event base to construct timeouts to avoid sliding due to the latency > between service and re-addition. I don't think it matters much for the specific goal of getting rid of regular timer ticks. I expect even a jiffies less kernel to emulate jiffies using CLOCK_MONOTONIC and some timer for quite some time. Basically on these kernels it will just be a bit more expensive too use, but not much. Of course add_timeout makes a nicer API in general, so it may be still a good idea. -Andi