Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751776AbVJTGz4 (ORCPT ); Thu, 20 Oct 2005 02:55:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751777AbVJTGz4 (ORCPT ); Thu, 20 Oct 2005 02:55:56 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:3982 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1751776AbVJTGzz (ORCPT ); Thu, 20 Oct 2005 02:55:55 -0400 Date: Thu, 20 Oct 2005 08:56:20 +0200 From: Ingo Molnar To: Steven Rostedt Cc: Thomas Gleixner , linux-kernel@vger.kernel.org Subject: Re: Ktimer / -rt9 (+custom) monotonic_clock going backwards. Message-ID: <20051020065620.GA27349@elte.hu> References: <20051019151138.GA7739@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: 0.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=0.0 required=5.9 tests=AWL autolearn=disabled SpamAssassin version=3.0.4 0.0 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 999 Lines: 30 * Steven Rostedt wrote: > > should be monotone - the latest -rt kernels include a debugging check > > for the monotonicity of do_get_ktime_mono(). > > Hi Ingo, > > Hmm, I think this will help in that debugging check :-) > + per_cpu(prev_mono_time, cpu) = now; > return now; > } *blush*, applied. I was already wondering a bit why that check never triggered for anyone. It is easy to have a non-monotonic clock (there's lots of crappy hw and the gettimeofday code has to work hard) and the effects of time warps are subtle, if noticeable at all, so i expected some detections. i have released -rt13 with another change: the other timer warning is only printed once. (a steady stream of messages is not helpful) Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/