Re: [PATCH 2/8] staging: omap-thermal: use spin_lock_irqsave insideIRQ handler

From: Dan Carpenter
Date: Mon Mar 18 2013 - 15:58:57 EST


On Mon, Mar 18, 2013 at 03:38:38PM -0400, Eduardo Valentin wrote:
> On 18-03-2013 15:16, Dan Carpenter wrote:
> >On Mon, Mar 18, 2013 at 10:59:10AM -0400, Eduardo Valentin wrote:
> >>Even if the IRQ is not firing because it is ONE_SHOT and disable
> >>at INTC level, the IRQ handler must use spin_lock_irqsave.
> >>It is necessary to disable IRQs from the current
> >>CPU while it is holding a spin_lock which is need.
> >>
> >
> >Gar... I think I was just totally wrong on this. I think your
> >original code was fine. Sorry Eduardo and Greg.
> >
> >This is a threaded IRQ so the regular spin_lock is fine or even the
> >mutex would have been.
>
> In fact it is. But I rather prefer to use spinlocks there, just to
> keep the irq handler sane, even if it is moved to non-threaded IRQ.

Yep. I'd agree there.

>
> >
> >IRQ_ONESHOT is about triggering a second IRQ before the first one
> >has been finished, btw.
>
> It is, and that gets done by masking the IRQ at INTC level.
>
> >
> >I am an idiot.
>
>
> Not really. Thanks for your time reviewing the driver.
>
> I will resend this series. Drop this one and split patch 4/8 into
> two I think (one for moving files, one for renaming functions)

Great. Much appreciated.

regards,
dan carpenter

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