Re: [RFC] remove linux/hardirq.h from asm-generic/local.h

[Geert Uytterhoeven <geert@linux-m68k.org>]

On Sun, 14 Dec 2008, Russell King wrote:
> While looking at reducing the amount of architecture namespace pollution
> in the generic kernel, I found that asm/irq.h is included in the vast
> majority of compilations on ARM (around 650 files.)
> 
> Since asm/irq.h includes a sub-architecture include file on ARM, this
> causes a negative impact on the ccache's ability to re-use the build
> results from other sub-architectures, so we have a desire to reduce
> the dependencies on asm/irq.h.
> 
> It turns out that a major cause of this is the needless include of
> linux/hardirq.h into asm-generic/local.h.  The patch below removes this
> include, resulting in some 250 to 300 files (around half) of the kernel
> then omitting asm/irq.h.
> 
> My test builds still succeed, provided two ARM files are fixed
> (arch/arm/kernel/traps.c and arch/arm/mm/fault.c) - so there may be
> negative impacts for this on other architectures.

I gave it a try on m68k/atari_defconfig, but no ill effects.

> Note that x86 does not include asm/irq.h nor linux/hardirq.h in its
> asm/local.h, so this patch can be viewed as bringing the generic version
> into line with the x86 version.
> 
> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
> 
> diff --git a/include/asm-generic/local.h b/include/asm-generic/local.h
> index 33d7d04..43c0b81 100644
> --- a/include/asm-generic/local.h
> +++ b/include/asm-generic/local.h
> @@ -2,7 +2,6 @@
>  #define _ASM_GENERIC_LOCAL_H
>  
>  #include <linux/percpu.h>
> -#include <linux/hardirq.h>
>  #include <asm/atomic.h>
>  #include <asm/types.h>

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds