From mboxrd@z Thu Jan  1 00:00:00 1970
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
Date: Fri, 27 Nov 2009 20:44:14 +0000
Subject: [RESENT PATCH] Don't disable irqs in set_next_event and
	set_mode callbacks
In-Reply-To: <20091127203823.GA28789@pengutronix.de>
References: <1253518763-15087-1-git-send-email-u.kleine-koenig@pengutronix.de>
	<1259231164-21242-1-git-send-email-u.kleine-koenig@pengutronix.de>
	<20091126105002.GB2393@n2100.arm.linux.org.uk>
	<20091126113158.GC2393@n2100.arm.linux.org.uk>
	<20091127104454.GA26570@pengutronix.de>
	<20091127195857.GB28193@n2100.arm.linux.org.uk>
	<20091127203823.GA28789@pengutronix.de>
Message-ID: <20091127204414.GD28193@n2100.arm.linux.org.uk>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Fri, Nov 27, 2009 at 09:38:23PM +0100, Uwe Kleine-K?nig wrote:
> OK, so this should make it save for mach-nomadik/timer.c,
> mach-pxa/time.c and mach-sa1100/time.c.
> 
> Only mach-at91/at91rm9200_time.c and mach-at91/at91sam926x_time.c
> request with IRQF_SHARED | IRQF_DISABLED.
> So for there the right solution is to let the local_irq_save in place
> and add a comment that it is needed as the timer irq is shared.
> This hopefully stopps people copying it unnecessarily.

Given that the gentime code spits out warnings if its called with IRQs
enabled, I don't think keeping the local_irq_save() in place is worth
it - especially given Thomas' response.

We've seen such warnings on AT91 (though I don't think we got positively
to the bottom of it with the reporter.)  If you _do_ want to ensure that
AT91 is safe, wrapping the call to dev->event_handler(dev) in the AT91
interrupt handler with a local_irq_save/local_irq_restore would seem
sensible.