From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756905Ab1KPQpL (ORCPT ); Wed, 16 Nov 2011 11:45:11 -0500 Received: from he.sipsolutions.net ([78.46.109.217]:35895 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756202Ab1KPQpJ (ORCPT ); Wed, 16 Nov 2011 11:45:09 -0500 Subject: Re: [PATCH] tracing: add trace console From: Johannes Berg To: Steven Rostedt Cc: Christoph Hellwig , LKML , Frederic Weisbecker , Ingo Molnar In-Reply-To: <1321461693.4181.26.camel@frodo> References: <1321438728.4773.16.camel@jlt3.sipsolutions.net> <20111116151037.GA26166@infradead.org> <1321456652.4502.12.camel@jlt3.sipsolutions.net> <1321461693.4181.26.camel@frodo> Content-Type: text/plain; charset="UTF-8" Date: Wed, 16 Nov 2011 17:45:02 +0100 Message-ID: <1321461902.4502.14.camel@jlt3.sipsolutions.net> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2011-11-16 at 11:41 -0500, Steven Rostedt wrote: > > That's possible, basically adding a tracepoints to printk -- that would > > even catch everything and not require setting the console level (which > > has its advantages too since other consoles might be slow). > > > > It's a completely different thing though. I did it this way because it > > was trivial to do out of tree for a quick test I was doing yesterday. > > Doing it the other way is obviously more intrusive in core code. > > I'm not sure it would be too invasive. Think you could get something > working? I briefly looked at it just after writing the email, but quickly got lost in printk.c because of the multi-line handling it has. We could instead trace each call to printk(), so the multi-line stuff would end up in multiple events, but all of that code is too much vodoo for me :) johannes