Re: [PATCH] mfd: speedup twl4030 irq response time and decrease irqdisable time

From: Ming Lei
Date: Tue Sep 28 2010 - 01:01:38 EST


CC genirq guys

2010/9/28 Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx>:
> On Tue, Sep 28, 2010 at 08:25:24AM +0800, Ming Lei wrote:
>> 2010/9/27 Samuel Ortiz <sameo@xxxxxxxxxxxxxxx>:
>
>> > Wouldn't converting your twl4030_irq_thread() to the threaded IRQ framework
>> > fix that problem ?
>
>> IRQ_DISABLED flag is set by disable_irq_nosync called from PIH handler,
>> then thread function can't be executed in irq thread function, so we can't
>> convert this to threaded IRQ framework simply.
>
> Have you raised this issue with the genirq guys?  This sounds like
> something that the core infrastructure should be able to cope with.
>

Even genirq guys can help us to convert to irq thread framework, I
don't think there is good way to set priority for one irq thread.

For twl4030, if we can make twl4030_irq_thread to run at higher
priority than that of other irq thread, the PIH irq disable time can be
decreased further since other irq thread waken up by twl4030_irq_thread
can preempt the running of twl4030_irq_thread, and the PIH irq will be
enabled until complete of twl4030_irq_thread.

thanks,
--
Lei Ming
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