From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 11 May 2002 02:58:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 11 May 2002 02:58:52 -0400 Received: from gateway-1237.mvista.com ([12.44.186.158]:21742 "EHLO av.mvista.com") by vger.kernel.org with ESMTP id ; Sat, 11 May 2002 02:58:50 -0400 Message-ID: <3CDCC118.5A659170@mvista.com> Date: Fri, 10 May 2002 23:58:32 -0700 From: george anzinger Organization: Monta Vista Software X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.2.12-20b i686) X-Accept-Language: en MIME-Version: 1.0 To: jim.houston@attbi.com CC: linux-kernel@vger.kernel.org Subject: Re: 64-bit jiffies, a better solution In-Reply-To: <3CDC9BDC.F96F7C36@attbi.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jim Houston wrote: > > Hi! > > First what problem are you trying to solve? > Why not have both variables and if they happen > to endup in the same cache line you probably > need years worth of jiffies to notice how > long one more add takes. E.g. > > jiffies_64++; > jiffies++; > > To round out the list of options, how about a few lines of > inline asm? Maybe something like: > > extern unsigned long long jiffie_64; > extern unsigned int jiffie; > __asm__ (" \ > .data > .align 8 > .global jiffie > .global jiffie_64 > .type jiffie,@object > .size jiffie,4 > .type jiffie_64,@object > .size jiffie_64,8 > jiffie_64: > jiffie: > .long 0, 0 > "); > > Adding the obvious ifdef of course. Aside for broken > binutils this might be portable code :-) Until you move to a big endian 32-bit machine. I would much rather hear IS portable. -- George Anzinger george@mvista.com High-res-timers: http://sourceforge.net/projects/high-res-timers/ Real time sched: http://sourceforge.net/projects/rtsched/ Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml