From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757350AbXHCIeu (ORCPT ); Fri, 3 Aug 2007 04:34:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753525AbXHCIem (ORCPT ); Fri, 3 Aug 2007 04:34:42 -0400 Received: from mx2.suse.de ([195.135.220.15]:48935 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752877AbXHCIek (ORCPT ); Fri, 3 Aug 2007 04:34:40 -0400 To: Matt Mackall Cc: Arjan van de Ven , Ingo Molnar , Roman Zippel , Mike Galbraith , Linus Torvalds , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: CFS review References: <20070711214649.GK14435@v2.random> <1184302024.6709.11.camel@Homer.simpson.net> <1184389456.6632.13.camel@Homer.simpson.net> <20070801112229.GA11710@elte.hu> <20070803030436.GO11166@waste.org> <1186113467.3996.0.camel@laptopd505.fenrus.org> <20070803043800.GE11115@waste.org> From: Andi Kleen Date: 03 Aug 2007 11:29:10 +0200 In-Reply-To: <20070803043800.GE11115@waste.org> Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 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 Matt Mackall writes: > > Indeed. I'm just pointing out that not having TSC, fast HZ, no-HZ > mode, or high-res timers should not be treated as an unusual > circumstance. That's a PC-centric view. The question is if it would be that hard to add TSC equivalent sched_clock() support to more systems. At least a lot of CPUs I have ever looked at had some kind of fast clock available. Perhaps it's more laziness of the developers or cut'n'paste that these are not as widely used as they should be? -Andi