RE: [RFC trollpatch 1/1] genirq: Remove the fits all and nothing__do_IRQ() code

From: Thomas Gleixner
Date: Mon Sep 27 2010 - 14:55:00 EST


On Mon, 27 Sep 2010, Luck, Tony wrote:

> > No, it's deliberate. The solution is to use the correct flow handler
> > for your device. We have currently several flow handlers implemented:
>
> Yes, I found the different "handle_*_irq()" functions. The _percpu_
> variant works fine for the ia64 per-cpu interrupt paths.
>
> But *NONE* of them call desc->chip->end() (even though the code flow
> in Documentation/DcoBook/genericirq.tmpl says that three of them do
> call it]. So it appears that this was thought to be necessary when
> the docs were written, but was not put into the code.

Yeah, sorry.

> The ia64 chip->end function for edge triggered interrupts is a nop(),
> so handle_edge_irq() ought to work just fine for it [can't confirm
> from my initial tests because the HP box I'm using only has level
> triggered ones].
>
> handle_level_irq() works for my level triggered interrupts if I add
> a "desc->chip->end(irq)" call to it.

Hmm, why isn't chip->unmask() sufficient ?

> git grep "chip->end" appears to show that the only use of chip->end
> is in the "Recovery handler for misrouted interrupts": try_one_irq()

Right, that's just due to the old __do_IRQ() compability.

> At minimum we seem to have some documentation inconsistencies with
> the code.

Will fix.

Thanks,

tglx
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/