Prev: dump/restore not supported for ext4
Next: Stage: hv: Corrected all header comments to follow kernel-doc format-CORRECTED
From: Thomas Gleixner on 4 Mar 2010 17:30
On Thu, 4 Mar 2010, Uwe Kleine-König wrote:
> -void note_interrupt(unsigned int irq, struct irq_desc *desc,
> - irqreturn_t action_ret)
> +void note_threaded_interrupt(unsigned int irq, struct irq_desc *desc,
> + irqreturn_t action_ret)
> {
> if (unlikely(action_ret != IRQ_HANDLED)) {
> /*
> @@ -262,6 +262,19 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc,
> desc->irqs_unhandled = 0;
> }
>
> +void note_interrupt(unsigned int irq, struct irq_desc *desc,
> + irqreturn_t action_ret)
> +{
> + if (action_ret == IRQ_WAKE_THREAD)
> + /* handled in irq_thread() when the threaded handler returns */
> + return;
> +
> + /* don't report IRQ_WAKE_THREAD | IRQ_HANDLED as bogus return value */
> + action_ret &= ~IRQ_WAKE_THREAD;
> +
> + note_threaded_interrupt(irq, desc, action_ret);
> +}
> +

We don't need an extra function for that. A simple

if (action_ret & IRQ_WAKE_THREAD)
return;

in note_interrupt() is sufficient to cover everything.

Thanks,

tglx
From: Uwe Kleine-König on 5 Mar 2010 03:00
On Thu, Mar 04, 2010 at 11:26:20PM +0100, Thomas Gleixner wrote:
> On Thu, 4 Mar 2010, Uwe Kleine-K�nig wrote:
> > -void note_interrupt(unsigned int irq, struct irq_desc *desc,
> > - irqreturn_t action_ret)
> > +void note_threaded_interrupt(unsigned int irq, struct irq_desc *desc,
> > + irqreturn_t action_ret)
> > {
> > if (unlikely(action_ret != IRQ_HANDLED)) {
> > /*
> > @@ -262,6 +262,19 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc,
> > desc->irqs_unhandled = 0;
> > }
> >
> > +void note_interrupt(unsigned int irq, struct irq_desc *desc,
> > + irqreturn_t action_ret)
> > +{
> > + if (action_ret == IRQ_WAKE_THREAD)
> > + /* handled in irq_thread() when the threaded handler returns */
> > + return;
> > +
> > + /* don't report IRQ_WAKE_THREAD | IRQ_HANDLED as bogus return value */
> > + action_ret &= ~IRQ_WAKE_THREAD;
> > +
> > + note_threaded_interrupt(irq, desc, action_ret);
> > +}
> > +
>
> We don't need an extra function for that. A simple
>
> if (action_ret & IRQ_WAKE_THREAD)
> return;
>
> in note_interrupt() is sufficient to cover everything.
With your suggestion if action_ret == IRQ_WAKE_THREAD | IRQ_HANDLED then
the IRQ_HANDLED bit doesn't get noted. Does that matter?

But still you're right about the extra function. Assuming a threaded
handler doesn't return IRQ_WAKE_THREAD my note_interrupt does the same
as note_threaded_interrupt.

Best regards
Uwe

--
Pengutronix e.K. | Uwe Kleine-K�nig |
Industrial Linux Solutions | http://www.pengutronix.de/ |
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
From: Thomas Gleixner on 5 Mar 2010 15:20
On Fri, 5 Mar 2010, Uwe Kleine-König wrote:

> For threaded irqs the top half returns IRQ_WAKE_THREAD. Don't treat
> that value like IRQ_HANDLED for the spurious check. Instead check the
> return value of the threaded handler to be able to detect stuck irqs
> that only have threaded handlers and no top half that can detect the
> problem.
>
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig(a)pengutronix.de>
> Cc: Thomas Gleixner <tglx(a)linutronix.de>
> Cc: Ingo Molnar <mingo(a)elte.hu>
> ---
> Hello,
>
> changed since v1:
>
> - use note_interrupt for the threaded handler's return value, getting rid of
> note_threaded_interrupt. The only downside is that a threaded handler
> returning IRQ_WAKE_THREAD remains uncatched now.

Well that's easy to fix.

> + if (!noirqdebug)
> + note_interrupt(action->irq, desc, action_ret);

note_interrupt(action->irq, desc,
action_ret & ~IRQ_WAKE_THREAD);
Thanks,

tglx
From: Uwe Kleine-König on 8 Mar 2010 04:10
Hey Thomas,

On Fri, Mar 05, 2010 at 09:16:53PM +0100, Thomas Gleixner wrote:
> On Fri, 5 Mar 2010, Uwe Kleine-K�nig wrote:
>
> > For threaded irqs the top half returns IRQ_WAKE_THREAD. Don't treat
> > that value like IRQ_HANDLED for the spurious check. Instead check the
> > return value of the threaded handler to be able to detect stuck irqs
> > that only have threaded handlers and no top half that can detect the
> > problem.
> >
> > Signed-off-by: Uwe Kleine-K�nig <u.kleine-koenig(a)pengutronix.de>
> > Cc: Thomas Gleixner <tglx(a)linutronix.de>
> > Cc: Ingo Molnar <mingo(a)elte.hu>
> > ---
> > Hello,
> >
> > changed since v1:
> >
> > - use note_interrupt for the threaded handler's return value, getting rid of
> > note_threaded_interrupt. The only downside is that a threaded handler
> > returning IRQ_WAKE_THREAD remains uncatched now.
>
> Well that's easy to fix.
>
> > + if (!noirqdebug)
> > + note_interrupt(action->irq, desc, action_ret);
>
> note_interrupt(action->irq, desc,
> action_ret & ~IRQ_WAKE_THREAD);
Hmmm, this makes IRQ_WAKE_THREAD be noted as IRQ_NONE.
If this is intended it IMHO deserves a comment. Something like:

/*
* The threaded handler must return IRQ_NONE or IRQ_HANDLED.
* As IRQ_WAKE_THREAD is handled special by note_interrupt
* report it as IRQ_NONE.
*/

Well and with that approach (IRQ_WAKE_THREAD | IRQ_HANDLED) is handled
as IRQ_HANDLED, but I think I start wasting time.

Actually I don't care what we do here, should I resend with action_ret &
~IRQ_WAKE_THREAD and the comment?

Best regards
Uwe

--
Pengutronix e.K. | Uwe Kleine-K�nig |
Industrial Linux Solutions | http://www.pengutronix.de/ |
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
 | 
Pages: 1
Prev: dump/restore not supported for ext4
Next: Stage: hv: Corrected all header comments to follow kernel-doc format-CORRECTED