From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754774AbXJ1Qye (ORCPT ); Sun, 28 Oct 2007 12:54:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751588AbXJ1Qy1 (ORCPT ); Sun, 28 Oct 2007 12:54:27 -0400 Received: from www.tglx.de ([62.245.132.106]:37617 "EHLO www.tglx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751365AbXJ1Qy0 (ORCPT ); Sun, 28 Oct 2007 12:54:26 -0400 Date: Sun, 28 Oct 2007 17:54:15 +0100 (CET) From: Thomas Gleixner To: Ralf Baechle cc: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [PATCH] Optimize i8259 code a bit. In-Reply-To: <20071028231145.GA9515@linux-mips.org> Message-ID: References: <20071028231145.GA9515@linux-mips.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 28 Oct 2007, Ralf Baechle wrote: > The timer code always calls the clock_event_device set_net_event and > set_mode methods with interrupts disabled, so no need to use > spin_lock_irqsave / spin_unlock_irqrestore for those. Good point, Acked-by:Thomas Gleixner > diff --git a/arch/mips/kernel/i8253.c b/arch/mips/kernel/i8253.c > index 5d9830d..1b54674 100644 > --- a/arch/mips/kernel/i8253.c > +++ b/arch/mips/kernel/i8253.c > @@ -23,9 +23,7 @@ static DEFINE_SPINLOCK(i8253_lock); > static void init_pit_timer(enum clock_event_mode mode, > struct clock_event_device *evt) > { > - unsigned long flags; > - > - spin_lock_irqsave(&i8253_lock, flags); > + spin_lock(&i8253_lock); > > switch(mode) { > case CLOCK_EVT_MODE_PERIODIC: > @@ -54,7 +52,7 @@ static void init_pit_timer(enum clock_event_mode mode, > /* Nothing to do here */ > break; > } > - spin_unlock_irqrestore(&i8253_lock, flags); > + spin_unlock(&i8253_lock); > } > > /* > @@ -64,12 +62,10 @@ static void init_pit_timer(enum clock_event_mode mode, > */ > static int pit_next_event(unsigned long delta, struct clock_event_device *evt) > { > - unsigned long flags; > - > - spin_lock_irqsave(&i8253_lock, flags); > + spin_lock(&i8253_lock); > outb_p(delta & 0xff , PIT_CH0); /* LSB */ > outb(delta >> 8 , PIT_CH0); /* MSB */ > - spin_unlock_irqrestore(&i8253_lock, flags); > + spin_unlock(&i8253_lock); > > return 0; > } > diff --git a/arch/x86/kernel/i8253.c b/arch/x86/kernel/i8253.c > index a42c807..5246515 100644 > --- a/arch/x86/kernel/i8253.c > +++ b/arch/x86/kernel/i8253.c > @@ -31,9 +31,7 @@ struct clock_event_device *global_clock_event; > static void init_pit_timer(enum clock_event_mode mode, > struct clock_event_device *evt) > { > - unsigned long flags; > - > - spin_lock_irqsave(&i8253_lock, flags); > + spin_lock(&i8253_lock); > > switch(mode) { > case CLOCK_EVT_MODE_PERIODIC: > @@ -62,7 +60,7 @@ static void init_pit_timer(enum clock_event_mode mode, > /* Nothing to do here */ > break; > } > - spin_unlock_irqrestore(&i8253_lock, flags); > + spin_unlock(&i8253_lock); > } > > /* > @@ -72,12 +70,10 @@ static void init_pit_timer(enum clock_event_mode mode, > */ > static int pit_next_event(unsigned long delta, struct clock_event_device *evt) > { > - unsigned long flags; > - > - spin_lock_irqsave(&i8253_lock, flags); > + spin_lock(&i8253_lock); > outb_p(delta & 0xff , PIT_CH0); /* LSB */ > outb(delta >> 8 , PIT_CH0); /* MSB */ > - spin_unlock_irqrestore(&i8253_lock, flags); > + spin_unlock(&i8253_lock); > > return 0; > } >