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Subject: Re: better leve triggered IRQ management needed
From: Arjan van de Ven <arjan@infradead.org>
To: Alan Cox <alan@redhat.com>
Cc: Linus Torvalds <torvalds@osdl.org>,
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Date: Mon, 24 Apr 2006 22:43:36 +0200
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On Mon, 2006-04-24 at 16:16 -0400, Alan Cox wrote:
> On Mon, Apr 24, 2006 at 09:53:22PM +0200, Arjan van de Ven wrote:
> > we now have that neat polling thing Alan did for interrupts (but which
> > is optional). To limp along better the kernel could auto-enable that for
> > any such shared interrupt automatically as a "safe fallback"...
> > (or heck, if things are this broken, you probably want it for all
> > interrupts at that point just to be sure)
> 
> That is really something drivers should handle themselves if they are doing
> shared edge trigger.

but the issue is .. drivers don't know. They didn't *want* edge trigger
in the first place generally

>  For one the kernel core has no idea the right polling
> time

well... the corner case (as rmk described) is full starvation; even
polling once per second is better than not polling at tall there.,..