Re: [PATCH] Fix irqpoll on IA64 (timer interrupt != 0)

[Andrew Morton <akpm@linux-foundation.org>]

On Thu, 22 Mar 2007 22:23:21 +0100
Thomas Gleixner <tglx@linutronix.de> wrote:

> On Thu, 2007-03-22 at 14:09 -0700, Andrew Morton wrote:
> > I think the term 'timer_interrupt' is a bit generic-sounding.  Would it be
> > better to call it irqpoll_interrupt?  After all, some architecture might
> > want to use, umm, the keyboard interrupt to trigger IRQ polling ;)  
> 
> Interesting thought, but in general I have to agree.
> 
> > Also, the code presently passes the magic IRQ number into the generic IRQ
> > code.  I wonder if we'd get a more pleasing result if we were to make the
> > generic IRQ code call _out_ to the architecture:
> 
> > Then, ia64 can implement arch_is_irqpoll_irq() and it can do whatever it
> > wants in there.
> > 
> > The __attribute__((weak)) thing adds a little bit of overhead, but I don't
> > think this is a fastpath?
> 
> Well, depends what you consider a fastpath. When noirqdebug = 0, it is
> called on every interrupt.
> 

OK, well the alternative is to do

extern bool __arch_irqpoll_irq(unsigned int irq);
#define arch_is_irqpoll_irq(irq)	__arch_is_irqpoll_irq(irq)

in an ia64 header file and then do

#ifndef arch_is_irqpoll_irq
static inline bool arch_is_irqpoll_irq(unsigned irq)
{
	return irq = 0;
}
#endif

in spurious.c