Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932295AbWIOVmB (ORCPT ); Fri, 15 Sep 2006 17:42:01 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932298AbWIOVmA (ORCPT ); Fri, 15 Sep 2006 17:42:00 -0400 Received: from outbound-blu.frontbridge.com ([65.55.251.16]:59367 "EHLO outbound2-blu-R.bigfish.com") by vger.kernel.org with ESMTP id S932295AbWIOVl7 (ORCPT ); Fri, 15 Sep 2006 17:41:59 -0400 X-BigFish: V Message-ID: <450B1ED1.3060508@am.sony.com> Date: Fri, 15 Sep 2006 14:44:49 -0700 From: Tim Bird User-Agent: Mozilla Thunderbird 0.9 (Windows/20041103) X-Accept-Language: en-us, en MIME-Version: 1.0 To: tglx@linutronix.de CC: Roman Zippel , Ingo Molnar , Alan Cox , "Frank Ch. Eigler" , karim@opersys.com, Mathieu Desnoyers , linux-kernel@vger.kernel.org, Christoph Hellwig , Andrew Morton , Ingo Molnar , Greg Kroah-Hartman , Tom Zanussi , ltt-dev@shafik.org, Michel Dagenais Subject: Re: [PATCH 0/11] LTTng-core (basic tracing infrastructure) 0.5.108 References: <1158323938.29932.23.camel@localhost.localdomain> <1158327696.29932.29.camel@localhost.localdomain> <1158331277.29932.66.camel@localhost.localdomain> <450ABA2A.9060406@opersys.com> <1158332324.29932.82.camel@localhost.localdomain> <1158345108.29932.120.camel@localhost.localdomain> <20060915181208.GA17581@elte.hu> <1158350716.5724.488.camel@localhost.localdomain> In-Reply-To: <1158350716.5724.488.camel@localhost.localdomain> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 15 Sep 2006 21:41:58.0418 (UTC) FILETIME=[C5479F20:01C6D90F] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1930 Lines: 49 Thomas Gleixner wrote: > On Fri, 2006-09-15 at 21:10 +0200, Roman Zippel wrote: > >>>this is being worked on actively: there's the "djprobes" patchset, which >>>includes a simplified disassembler to analyze common target code and can >>>thus insert much faster, call-a-trampoline-function based tracepoints >>>that are just as fast as (or faster than) compile-time, static >>>tracepoints. >> >>Who is going to implement this for every arch? >>Is this now the official party line that only archs, which implement all >>of this, can make use of efficient tracing? > > In the reverse you are enforcing an ugly - but available for all archs - > solution due to the fact that there is nobody interested enough to > implement it ? ???? If there's a solution people are willing to implement, and one they aren't - doesn't that say something? Static tracepoint patches for numerous architectures have existed and been maintained out-of-tree for years. > If there is no interest to do that, then this arch can probably live w/o > instrumentation for the next decade too. The arches already have instrumentation - just not dynamic instrumentation. The reason static tracepoints have been implemented and kprobes haven't is that static tracepoints are sufficient for what those people are doing, and dynamic tracepoints are a pain to implement. Let me repeat that, just in case people missed it: "Static tracepoints work for what I need." If other people want to implement something fancier that works for them, then feel free. ============================= Tim Bird Architecture Group Chair, CE Linux Forum Senior Staff Engineer, Sony Electronics ============================= - 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/