Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760677AbYGOBn5 (ORCPT ); Mon, 14 Jul 2008 21:43:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753206AbYGOBns (ORCPT ); Mon, 14 Jul 2008 21:43:48 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:56640 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752352AbYGOBns (ORCPT ); Mon, 14 Jul 2008 21:43:48 -0400 Date: Mon, 14 Jul 2008 21:43:46 -0400 (EDT) From: Steven Rostedt X-X-Sender: rostedt@gandalf.stny.rr.com To: "Eric W. Biederman" cc: Andrew Morton , Randy Dunlap , Elias Oltmanns , LKML , Ingo Molnar , Thomas Gleixner , Peter Zijlstra , Clark Williams , Linus Torvalds , Jon Masters Subject: Re: [PATCH -v2] ftrace: Documentation In-Reply-To: Message-ID: References: <87zlop7bp6.fsf@denkblock.local> <20080710132832.38cc5048.randy.dunlap@oracle.com> <20080711121655.05810822.akpm@linux-foundation.org> <20080711153740.b86acadd.akpm@linux-foundation.org> 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: 1403 Lines: 42 On Mon, 14 Jul 2008, Eric W. Biederman wrote: > > Steven Rostedt writes: > > > Actually it is a /debug (or /sys/mount/debug if you prefer) file. > > Got it. I haven't ever actually seen anyone use debugfs. > > > I'd be interested in knowing who would want namespaces in traces. I've > > basically only used tracing to see "what's happening in the kernel here?". > > Where I only use the pid to differentiate between the tasks I know are > > running. > > > Hence, tracing is much like printk. Does it really matter with these > > outputs. But ftrace is pluggable, pid namespaces may matter in future > > plugins. Bare with me, I'm new to the namespace concept of pids. > > So it would not be hard to capture the pid namespace in mount or > even look at current to get it (although the last is a little odd). >From userspace or from with the kernel (doing the trace) > > I'm not at all certain if it makes sense. If this is something > an ordinary user could use then we definitely want to do something. > > Is tracing possible without inserting kernel modules? The tracer is built into the kernel (no module needed). -- Steve -- 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/