Hello, (including linux-rt-users in the CC:, irqthreads are on-topic there) On Wed, Jul 2, 2008 at 1:02 PM, Andi Kleen <andi@xxxxxxxxxxxxxx> wrote: > Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> writes: > >>> how much of this would be obsoleted if we had irqthreads ? >> >> I'm not sure irqthreads is what I want... >> > I also think interrupts threads are a bad idea in many cases because > their whole "advantage" over classical interrupts is that they can > block. Now blocking can be usually take a unbounded potentially long > time. > > What do you do when there are more interrupts in that unbounded time? > If by irqthreads the -rt implementation is meant, isn't this what happens: irq kernel handler masks the source interrupt irq handler awakes the matching irqthread (they always are present) irqthread is scheduled, does work and returns irq kernel unmasks the source interrupt > Create more interrupt threads? At some point you'll have hundreds > of threads doing nothing when you're unlucky. > Each irqthread handles one irq. So now new irq thread would spawn for any interrupt. Regards, -- Leon -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
