ACK: Oneiric SRU: genirq: Fix irqfixup, irqpoll regression

[Stefan Bader]

On 21.11.2011 01:44, Tim Gardner wrote:
> From 3f21b6ce938f2df057659e2e1cdbeddac0bda3c8 Mon Sep 17 00:00:00 2001
> From: Edward Donovan <edward.donovan at numble.net>
> Date: Tue, 1 Nov 2011 15:29:44 -0400
> Subject: [PATCH] genirq: Fix irqfixup, irqpoll regression
> 
> BugLink: http://bugs.launchpad.net/bugs/855199
> 
> commit d05c65fff0 ("genirq: spurious: Run only one poller at a time")
> introduced a regression, leaving the boot options 'irqfixup' and
> 'irqpoll' non-functional. The patch placed tests in each function, to
> exit if the function is already running. The test in 'misrouted_irq'
> exited when it should have proceeded, effectively disabling
> 'misrouted_irq' and 'poll_spurious_irqs'.
> 
> The check for an already running poller needs to be "!= 1" not "== 1"
> as "1" is the value when the first poller starts running.
> 
> Signed-off-by: Edward Donovan <edward.donovan at numble.net>
> Cc: maciej.rutecki at gmail.com
> Link: http://lkml.kernel.org/r/1320175784-6745-1-git-send-email-edward.donovan@numble.net
> Cc: stable at vger.kernel.org # >= 2.6.39
> Signed-off-by: Thomas Gleixner <tglx at linutronix.de>
> (cherry picked from commit c75d720fca8a91ce99196d33adea383621027bf2)
> 
> Signed-off-by: Tim Gardner <tim.gardner at canonical.com>
> ---
>  kernel/irq/spurious.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
> index aa57d5d..b5f4742 100644
> --- a/kernel/irq/spurious.c
> +++ b/kernel/irq/spurious.c
> @@ -115,7 +115,7 @@ static int misrouted_irq(int irq)
>  	struct irq_desc *desc;
>  	int i, ok = 0;
>  
> -	if (atomic_inc_return(&irq_poll_active) == 1)
> +	if (atomic_inc_return(&irq_poll_active) != 1)
>  		goto out;
>  
>  	irq_poll_cpu = smp_processor_id();

Seems to be doing what it claims.