From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761114AbZBLXZX (ORCPT ); Thu, 12 Feb 2009 18:25:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753318AbZBLXZJ (ORCPT ); Thu, 12 Feb 2009 18:25:09 -0500 Received: from mx2.redhat.com ([66.187.237.31]:60897 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753214AbZBLXZI (ORCPT ); Thu, 12 Feb 2009 18:25:08 -0500 Date: Thu, 12 Feb 2009 21:24:59 -0200 From: Arnaldo Carvalho de Melo To: Frederic Weisbecker Cc: Steven Rostedt , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] rt/threadirqs: don't need to save irqs in do_hardirq() Message-ID: <20090212232459.GD5348@ghostprotocols.net> References: <4994ae18.1358560a.454d.403b@mx.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4994ae18.1358560a.454d.403b@mx.google.com> X-Url: http://oops.ghostprotocols.net:81/blog User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Thu, Feb 12, 2009 at 07:27:08PM +0100, Frederic Weisbecker escreveu: > do_hardirq() has only one caller do_irqd() in a path where irq are already > disabled. So we don't need to save irqs while holding desc->lock > > Replace spin_lock_irqsave by spin_lock. > > Signed-off-by: Frederic Weisbecker > --- > kernel/irq/manage.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c > index ed7c5e3..6e9baf8 100644 > --- a/kernel/irq/manage.c > +++ b/kernel/irq/manage.c > @@ -905,7 +905,7 @@ static void do_hardirq(struct irq_desc *desc) > { > unsigned long flags; Can flags be removed too? > - spin_lock_irqsave(&desc->lock, flags); > + spin_lock(&desc->lock); > > if (!(desc->status & IRQ_INPROGRESS)) > goto out; > @@ -921,7 +921,7 @@ static void do_hardirq(struct irq_desc *desc) > else > thread_do_irq(desc); > out: > - spin_unlock_irqrestore(&desc->lock, flags); > + spin_unlock(&desc->lock); > > if (waitqueue_active(&desc->wait_for_handler)) > wake_up(&desc->wait_for_handler);