From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261369AbVALULX (ORCPT ); Wed, 12 Jan 2005 15:11:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261332AbVALT7o (ORCPT ); Wed, 12 Jan 2005 14:59:44 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.31.123]:38297 "EHLO atrey.karlin.mff.cuni.cz") by vger.kernel.org with ESMTP id S261326AbVALTqz (ORCPT ); Wed, 12 Jan 2005 14:46:55 -0500 Date: Tue, 11 Jan 2005 21:18:10 +0100 From: Pavel Machek To: Mikael Pettersson Cc: Pavel Machek , Bernard Blackham , Shaw , linux-kernel@vger.kernel.org Subject: Re: Screwy clock after apm suspend Message-ID: <20050111201810.GA1464@openzaurus.ucw.cz> References: <20050109224711.GF1353@elf.ucw.cz> <200501092328.54092.shawv@comcast.net> <20050110074422.GA17710@mussel> <20050110105759.GM1353@elf.ucw.cz> <20050110174804.GC4641@blackham.com.au> <20050111001426.GF1444@elf.ucw.cz> <20050111011611.GE4641@blackham.com.au> <16867.51258.916944.195917@alkaid.it.uu.se> <20050111131019.GA1324@openzaurus.ucw.cz> <16867.57217.358323.945559@alkaid.it.uu.se> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <16867.57217.358323.945559@alkaid.it.uu.se> User-Agent: Mutt/1.3.27i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! > > > > Looking harder, in arch/i386/kernel/apm.c the system time is also > > > > saved and restored in a very similar way to timer_suspend/resume. > > > > Would this account for the time drift in APM mode? (sleep time being > > > > accounted for twice?) > > > > > > No, apm.c's update to xtime is absolute, just like time.c's. > > > Doing both is pointless but not harmful. (I've already tried > > > with apm.c's xtime update commented out, but the time-warp > > > bug remained.) > > > > > > My 0.02 SEK says it's the jiffies update that's broken. > > > > Okay, can you > > > > * kill jiffie update (x86-64, too) > > * remove apm.c variant > > * test it (or make someone test it) with apm? > > > > I now see the drift with acpi, too :-(. I can do the acpi testing... > > I'm away from my APM laptop until Friday, but I'll do this test then. Now I recall why jiffies need to be updated: if they are not, ps shows wrong process start times after resume. If it causes worse problems, we may temporarily back that out, but... Pavel -- 64 bytes from 195.113.31.123: icmp_seq=28 ttl=51 time=448769.1 ms