Re: [PATCH 12/14] x86_64 irq: Add constants for the reserved IRQ vectors.

[Pavel Machek <pavel@ucw.cz>]

On Sun 2007-02-25 04:15:30, Eric W. Biederman wrote:
> Pavel Machek <pavel@ucw.cz> writes:
> 
> > Hi!
> >
> >> For the ISA irqs we reserve 16 vectors.  This patch adds constants for
> >> those vectors and modifies the code to use them.  Making the code a
> >> little clearer and making it possible to move these vectors in the future.
> >
> >
> >>  /*
> >>   * Vectors 0x20-0x2f are used for ISA interrupts.
> >>   */
> >> +#define IRQ0_VECTOR		FIRST_EXTERNAL_VECTOR
> >> +#define IRQ1_VECTOR		IRQ0_VECTOR + 1
> >
> > Maybe IRQ_VECTOR(1) would be similary readable, and would avoid 
> >
> >> +#define IRQ2_VECTOR		IRQ0_VECTOR + 2
> >> +#define IRQ3_VECTOR		IRQ0_VECTOR + 3
> >> +#define IRQ4_VECTOR		IRQ0_VECTOR + 4
> >> +#define IRQ5_VECTOR		IRQ0_VECTOR + 5 
> >> +#define IRQ6_VECTOR		IRQ0_VECTOR + 6
> >> +#define IRQ7_VECTOR		IRQ0_VECTOR + 7
> >> +#define IRQ8_VECTOR		IRQ0_VECTOR + 8
> >> +#define IRQ9_VECTOR		IRQ0_VECTOR + 9
> >> +#define IRQ10_VECTOR		IRQ0_VECTOR + 10
> >> +#define IRQ11_VECTOR		IRQ0_VECTOR + 11
> >> +#define IRQ12_VECTOR		IRQ0_VECTOR + 12
> >> +#define IRQ13_VECTOR		IRQ0_VECTOR + 13
> >> +#define IRQ14_VECTOR		IRQ0_VECTOR + 14
> >> +#define IRQ15_VECTOR		IRQ0_VECTOR + 15
> >
> > ...these defines?
> 
> It would, and mostly I like it.  However, of the 1500+ possible irqs
> exactly 16 have a reserved vector.  IRQ_VECTOR(N) does not convey
> that in fact it conveys the opposite impression.
> 
> So I think the code is more maintainable with the distinct
> definitions.

BUILD_BUG_ON(x > 15) ? ;-).
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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