From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752122Ab1GXJA7 (ORCPT ); Sun, 24 Jul 2011 05:00:59 -0400 Received: from www.linutronix.de ([62.245.132.108]:42716 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751534Ab1GXJAx (ORCPT ); Sun, 24 Jul 2011 05:00:53 -0400 Date: Sun, 24 Jul 2011 11:00:41 +0200 (CEST) From: Thomas Gleixner To: "Paul E. McKenney" cc: Peter Zijlstra , laijs@cn.fujitsu.com, darren@dvhart.com, rostedt@goodmis.org, mingo@elte.hu, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC] rtmutex: Permit rt_mutex_unlock() to be invoked with irqs disabled In-Reply-To: <20110724051744.GF2415@linux.vnet.ibm.com> Message-ID: References: <20110719201410.GA10553@linux.vnet.ibm.com> <1311247968.29152.122.camel@twins> <20110723220348.GD2415@linux.vnet.ibm.com> <20110724051744.GF2415@linux.vnet.ibm.com> User-Agent: Alpine 2.02 (LFD 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 23 Jul 2011, Paul E. McKenney wrote: > On Sun, Jul 24, 2011 at 02:05:13AM +0200, Thomas Gleixner wrote: > > On Sun, 24 Jul 2011, Thomas Gleixner wrote: > > > > > Thomas, I'm inclined to merge this, any objections? > > > > > > > > FWIW, it has been passing tests here. > > > > > > If it's only the unlock path, I'm fine with that change. > > > > > > Acked-by-me > > > > Hrmpft. That's requiring all places to take the lock irq safe. Not > > really amused. For -RT that's a hotpath and we can really do without > > the irq fiddling there. That needs a bit more thought. > > Indeed... If I make only some of the lock acquisitions irq safe, lockdep > will yell at me. And rightfully so, as that could result in deadlock. > > So, what did you have in mind? Have no real good idea yet for this. Could you grab rt and check whether you can observe any impact when the patch is applied? Thanks, tglx