From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264402AbTDOIno (for ); Tue, 15 Apr 2003 04:43:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264408AbTDOIno (for ); Tue, 15 Apr 2003 04:43:44 -0400 Received: from caramon.arm.linux.org.uk ([212.18.232.186]:1801 "EHLO caramon.arm.linux.org.uk") by vger.kernel.org with ESMTP id S264402AbTDOInn (for ); Tue, 15 Apr 2003 04:43:43 -0400 Date: Tue, 15 Apr 2003 09:55:28 +0100 From: Russell King To: george anzinger Cc: Andrew Morton , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] Fix jiffies_to_time[spec | val] and converse to use actual jiffies increment rather than 1/HZ Message-ID: <20030415095528.B32468@flint.arm.linux.org.uk> Mail-Followup-To: george anzinger , Andrew Morton , "linux-kernel@vger.kernel.org" References: <3E9BC49E.7010903@mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <3E9BC49E.7010903@mvista.com>; from george@mvista.com on Tue, Apr 15, 2003 at 01:36:46AM -0700 X-Message-Flag: Your copy of Microsoft Outlook is vurnerable to viruses. See www.mutt.org for more details. Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 15, 2003 at 01:36:46AM -0700, george anzinger wrote: > In the current system (2.5.67) time_spec to jiffies, time_val to > jiffies and the converse (jiffies to time_val and jiffies to > time_spec) all use 1/HZ as the measure of a jiffie. Because of the > inability of the PIT to actually generate an accurate 1/HZ interrupt, > the wall clock is updated with a more accurate value (999848 > nanoseconds per jiffie for HZ = 1000). There's an increasing amount of 64-bit math appearing here, which gcc has been historically bad with. Is there any chance that all this extra complexity can vanish for architectures which do not have this problem? -- Russell King (rmk@arm.linux.org.uk) The developer of ARM Linux http://www.arm.linux.org.uk/personal/aboutme.html