From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753772AbYHLPER (ORCPT ); Tue, 12 Aug 2008 11:04:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752419AbYHLPEF (ORCPT ); Tue, 12 Aug 2008 11:04:05 -0400 Received: from tomts36.bellnexxia.net ([209.226.175.93]:41032 "EHLO tomts36-srv.bellnexxia.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752240AbYHLPEE (ORCPT ); Tue, 12 Aug 2008 11:04:04 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApsEADRAoUhMRKxB/2dsb2JhbACBYK1tgSk Date: Tue, 12 Aug 2008 11:04:01 -0400 From: Mathieu Desnoyers To: ltt-dev@lists.casi.polymtl.ca, linux-kernel@vger.kernel.org Cc: Steven Rostedt , Arnaldo Carvalho de Melo , Andrew Morton Subject: LTTng 0.16 for 2.6.27-rc2 (ftrace integration) Message-ID: <20080812150401.GB11838@Krystal> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.6.21.3-grsec (i686) X-Uptime: 10:51:41 up 68 days, 19:32, 7 users, load average: 5.08, 2.35, 1.18 User-Agent: Mutt/1.5.16 (2007-06-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I just released the latest LTTng version I used to pinpoint the "prove locking correctness" latency issue. It integrates with ftrace (only the dynamic function tracing part) with what I call a "tap". See http://lkml.org/lkml/2008/8/5/321 to find out how I dug in this problem. Basically, a "tap" is a set of "enable/disable" probes one can connect on specific markers/tracepoints. These probes enable/disable a "tap", which controls recording of specific events to the trace. Since dynamic function tracing is very high overhead, this tap mechanism can be used to control the event flow to only trace the interesting code areas. All markers named "tap_*" are also controlled by such mechanism. By removing a comment from the ltt-armall script, one can use the tap to enable lockdep event tracing. See the new ltt-armtap and the modified ltt-armall scripts in the ltt-control package for details. New versions : LTTng gitweb http://git.kernel.org/?p=linux/kernel/git/compudj/linux-2.6-lttng.git;a=shortlog;h=2.6.27-rc2-lttng LTTng Git tree git://git.kernel.org/pub/scm/linux/kernel/git/compudj/linux-2.6-lttng.git 2.6.27-rc2-lttng LTTng tarball http://www.kernel.org/pub/linux/kernel/people/compudj/patches/2.6/2.6.27-rc2/lttng-2.6.27-rc2-0.16.tar.bz2 ltt-control http://ltt.polymtl.ca/lttng/ltt-control-0.51-12082008.tar.gz LTTV http://ltt.polymtl.ca/packages/lttv-0.10.0-pre15-12082008.tar.gz Testing, especially of the new tap scripts, is welcome. Mathieu -- Mathieu Desnoyers OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68