Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751114AbWINUJh (ORCPT ); Thu, 14 Sep 2006 16:09:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751119AbWINUJh (ORCPT ); Thu, 14 Sep 2006 16:09:37 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:4310 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1751114AbWINUJg (ORCPT ); Thu, 14 Sep 2006 16:09:36 -0400 Date: Thu, 14 Sep 2006 22:00:40 +0200 From: Ingo Molnar To: Tim Bird Cc: Roman Zippel , Mathieu Desnoyers , linux-kernel@vger.kernel.org, Christoph Hellwig , Andrew Morton , Ingo Molnar , Greg Kroah-Hartman , Thomas Gleixner , Tom Zanussi , ltt-dev@shafik.org, Michel Dagenais Subject: Re: [PATCH 0/11] LTTng-core (basic tracing infrastructure) 0.5.108 Message-ID: <20060914200040.GB5812@elte.hu> References: <20060914033826.GA2194@Krystal> <20060914112718.GA7065@elte.hu> <20060914135548.GA24393@elte.hu> <20060914171320.GB1105@elte.hu> <20060914181557.GA22469@elte.hu> <4509B03A.3070504@am.sony.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4509B03A.3070504@am.sony.com> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -2.9 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.9 required=5.9 tests=ALL_TRUSTED,AWL,BAYES_50 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts 0.5 BAYES_50 BODY: Bayesian spam probability is 40 to 60% [score: 0.5000] -0.1 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: 1459 Lines: 31 * Tim Bird wrote: > > that's not true, and this is the important thing that i believe you > > are missing. A dynamic tracepoint is _detached_ from the normal > > source code and thus is zero maintainance overhead. You dont have to > > maintain it during normal development - only if you need it. You > > dont see the dynamic tracepoints in the source code. > > It's only zero maintenance overhead for you. Someone has to maintain > it. The party line for years has been that in-tree maintenance is > easier than out-of-tree maintenance. There's a third option, and that's the one i'm advocating: adding the tracepoint rules to the kernel, but in a _detached_ form from the actual source code. yes, someone has to maintain it, but that will be a detached effort, on a low-frequency as-needed basis. It doesnt slow down or hinder high-frequency fast prototyping work, it does not impact the source code visually, and it does not make reading the code harder. Furthermore, while a single broken LTT tracepoint prevents the kernel from building at all, a single broken dynamic rule just wont be inserted into the kernel. All the other rules are still very much intact. 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/