From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752686Ab1LVHEI (ORCPT ); Thu, 22 Dec 2011 02:04:08 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:41372 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751542Ab1LVHEH (ORCPT ); Thu, 22 Dec 2011 02:04:07 -0500 Date: Thu, 22 Dec 2011 08:02:12 +0100 From: Ingo Molnar To: Linus Torvalds Cc: Peter Zijlstra , "Ted Ts'o" , Greg KH , Thomas Gleixner , akpm@linux-foundation.org, linux-kernel Subject: Re: [RFC][PATCH 6/7] printk: Poke printk extra hard Message-ID: <20111222070212.GA9593@elte.hu> References: <20111221105739.798864333@chello.nl> <20111221111143.620776435@chello.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes 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 * Linus Torvalds wrote: > On Wed, Dec 21, 2011 at 2:57 AM, Peter Zijlstra wrote: > > > > > > +#ifdef CONFIG_PRINTK_DEBUG > > +void printk_init(void) > > +{ > > +       struct rq *rq; > > +       unsigned long flags; > > + > > +       local_irq_save(flags); > > +       rq = this_rq(); > > +       raw_spin_lock(&rq->lock); > > +       printk(KERN_DEBUG "printk: echo echo echo..\n"); > > +       raw_spin_unlock(&rq->lock); > > +       local_irq_restore(flags); > > Ok, I can't really say that I think this is worth a config option like this. > > Maybe an example module or something? > > And I don't know *why*, but my immediate reaction to the > message was that it either should be serious and say what it > tested ("printk() works under rq lock"), or it should say > "Bork bork bork". "echo echo echo" sounds just stupid. We could perhaps use the standard mike test message: printk: Tap, tap, is this thing on? Thanks, Ingo