Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754798AbZCUJNT (ORCPT ); Sat, 21 Mar 2009 05:13:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753103AbZCUJNG (ORCPT ); Sat, 21 Mar 2009 05:13:06 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:39996 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753008AbZCUJNF (ORCPT ); Sat, 21 Mar 2009 05:13:05 -0400 Date: Sat, 21 Mar 2009 10:12:35 +0100 From: Ingo Molnar To: Andrew Morton Cc: Roland McGrath , Steven Rostedt , utrace-devel@redhat.com, Frank Eigler , linux-kernel@vger.kernel.org, Linus Torvalds , Peter Zijlstra , Thomas Gleixner Subject: Re: [PATCH 3/3] utrace-based ftrace "process" engine, v2 Message-ID: <20090321091235.GA29678@elte.hu> References: <20090321013946.890F4FC3AB@magilla.sf.frob.com> <20090321014244.9ADF1FC3AB@magilla.sf.frob.com> <20090321074301.GA19384@elte.hu> <20090321013912.ed6039c9.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090321013912.ed6039c9.akpm@linux-foundation.org> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2137 Lines: 52 * Andrew Morton wrote: > On Sat, 21 Mar 2009 08:43:01 +0100 Ingo Molnar wrote: > > > > > * Roland McGrath wrote: > > > > > From: Frank Ch. Eigler > > > > > > This is v2 of the prototype utrace-ftrace interface. This code is > > > based on Roland McGrath's utrace API, which provides programmatic > > > hooks to the in-tree tracehook layer. This new patch interfaces > > > many of those events to ftrace, as configured by a small number of > > > debugfs controls. Here's the > > > /debugfs/tracing/process_trace_README: > > > > Please submit changes/enhancements to kernel/trace/* to the tracing > > tree maintainers (Steve and me) for review, testing and integration. > > > > Please also post patches against the latest tracing tree: > > > > http://people.redhat.com/mingo/tip.git/README > > uhm, this patch depends on the (large) utrace patch, which is not > kernel/trace material. The thing is, utrace crashes in Fedora have dominated kerneloops.org for many months, so i'm not sure what to make of the idea of posting a 4000+ lines of core kernel code patchset on the last day of the development cycle, a posting that has carefully avoided the Cc:-ing of affected maintainers ;-) Utrace is very much tracing material - without the ftrace plugin the whole utrace machinery is just something that provides a _ton_ of hooks to something entirely external: SystemTap mainly. kernel/utrace.c should probably be introduced as kernel/trace/utrace.c not kernel/utrace.c. It also overlaps pending work in the tracing tree and cooperation would be nice and desired. The ftrace/utrace plugin is the only real connection utrace has to the mainline kernel, so proper review by the tracing folks and cooperation with the tracing folks is very much needed for the whole thing. Ingo -- 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/