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Date: Mon, 27 Sep 2010 20:49:49 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: "Luck, Tony" <tony.luck@intel.com>
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        Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: RE: [RFC trollpatch 1/1] genirq: Remove the fits all and nothing
 __do_IRQ() code
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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