Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756598AbZCGU1e (ORCPT ); Sat, 7 Mar 2009 15:27:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756196AbZCGU10 (ORCPT ); Sat, 7 Mar 2009 15:27:26 -0500 Received: from mx2.redhat.com ([66.187.237.31]:47698 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755912AbZCGU1Z (ORCPT ); Sat, 7 Mar 2009 15:27:25 -0500 To: Frederic Weisbecker Cc: Ingo Molnar , LKML , Lai Jiangshan , Steven Rostedt , Peter Zijlstra , Mathieu Desnoyers , Jiaying Zhang , Martin Bligh Subject: Re: [RFC][PATCH 0/2] Syscalls tracing References: <1236401580-5758-1-git-send-email-fweisbec@gmail.com> From: fche@redhat.com (Frank Ch. Eigler) Date: Sat, 07 Mar 2009 15:26:49 -0500 In-Reply-To: <1236401580-5758-1-git-send-email-fweisbec@gmail.com> (Frederic Weisbecker's message of "Sat, 7 Mar 2009 05:52:58 +0100") Message-ID: User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/21.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1150 Lines: 27 Frederic Weisbecker writes: > Here is a first attempt, quick one-shot, to provide a syscall tracing > infrastructure on ftrace. Please see also the utrace-based thread syscall/signal/lifecycle. tracer I posted a few times, and is just about to be reposted as a part of the larger utrace submission. System call metadata (name, argument count, and getting fancier from there) would be nice to have for other clients too, such as the audit subsystem. The main drawback of this general approach however is the notion that ftrace is the solitary user of system call tracing, thus dedicating that new task flag to this purpose. Therefore, your code has nothing like reference counting or sharing; nothing yet to avoid overhead on threads that need no tracing, nor to allow more than one tracing widget to consume events. These are the sorts of services that utrace provides. - FChE -- 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/