From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932555AbWJFBer (ORCPT ); Thu, 5 Oct 2006 21:34:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932556AbWJFBer (ORCPT ); Thu, 5 Oct 2006 21:34:47 -0400 Received: from tomts22-srv.bellnexxia.net ([209.226.175.184]:31729 "EHLO tomts22-srv.bellnexxia.net") by vger.kernel.org with ESMTP id S932555AbWJFBeq (ORCPT ); Thu, 5 Oct 2006 21:34:46 -0400 Date: Thu, 5 Oct 2006 21:29:37 -0400 From: Mathieu Desnoyers To: Steven Rostedt Cc: LKML , Ingo Molnar , Thomas Gleixner , Karim Yaghmour , Andrew Morton , Chris Wright , fche@redhat.com, Tom Zanussi Subject: Re: [RFC] The New and Improved Logdev (now with kprobes!) Message-ID: <20061006012936.GA19300@Krystal> References: <1160025104.6504.30.camel@localhost.localdomain> <20061005143133.GA400@Krystal> <20061005170132.GA11149@Krystal> <20061005205055.GB1865@Krystal> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.4.32-grsec (i686) X-Uptime: 21:26:41 up 43 days, 22:35, 3 users, load average: 0.06, 0.08, 0.09 User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Steven Rostedt (rostedt@goodmis.org) wrote: > > > Please don't :) Defining a new event would be to say : > > > > I want to create an event named "schedchange", which belongs to the "kernel" > > subsystem. In its definition, I say that it will take two integers and a long, > > respectively names "prev_pid", "next_pid" and "state". > > > > We can think of various events for various subsystems, and even for modules. It > > becomes interesting to have dynamically loadable event definitions which gets > > loaded with kernel modules. The "description" of the events is saved in the > > trace, in a special low traffic channel (small buffers with a separate file). > > > > But these events still need the marker in the source code right? > Yes, but not necessarily. But it could also be a kernel module built on-the-fly by a generator like SystemTAP which defines new events. > > That should definitely be a step. If I'm understanding this (which I may > not be), you can have a dynamic event added with also using dynamic > trace points like kprobes. > Yes, we could use a kprobes based approach with only one data type (string is always a good example), but we could also define one specific event and its associates data types for each probes. > No prob, I should read the rest of the thread, and try to catch up more, > before posting more comments. > No problem, constructive comments and ideas are always welcome. Mathieu OpenPGP public key: http://krystal.dyndns.org:8080/key/compudj.gpg Key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68