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From: Thomas Gleixner <tglx@linutronix.de>
To: David Jander <david.jander@protonic.nl>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Why does handle_simple_irq() require IRQ's to be disabled?
Date: Mon, 6 Jun 2011 18:18:41 +0200 (CEST)	[thread overview]
Message-ID: <alpine.LFD.2.02.1106061816280.13964@ionos> (raw)
In-Reply-To: <20110606172840.322f09d4@archvile>

On Mon, 6 Jun 2011, David Jander wrote:
> 
> Hi,
> 
> I am trying to implement/fix interrupt controller functionality in
> gpio/pca953x.c, and for some reason which I don't understand, I need to disable
> interrupts with local_irq_disable() before calling generic_handle_irq(). This
> does not seem right.
> If I follow the code of handle_simple_irq(), the handler function setup for
> this IRQ, I get to handle_irq_event_percpu(), which has a
> WARN_ONCE(!irqs_disabled(),...
> This WARN is triggered, since nobody explicitly disables interrupts. Why?
>  
> generic_hanlde_irq() is called from a threaded interrupt handler of the parent
> of this interrupt controller, and calling local_irq_disable() here seems like
> a crime. What am I doing wrong?

handle_nested_irq() is your friend.

  reply	other threads:[~2011-06-06 16:18 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-06 15:28 Why does handle_simple_irq() require IRQ's to be disabled? David Jander
2011-06-06 16:18 ` Thomas Gleixner [this message]
2011-06-07  7:05   ` David Jander
2011-06-07  8:26     ` Thomas Gleixner
2011-06-07  8:55       ` David Jander

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