Re: [PATCH 5/14] arch/m68k/mm/Sun3mmu.c: Eliminate NULL test andmemset after alloc_bootmem

From: Geert Uytterhoeven
Date: Sun Jun 29 2008 - 05:58:27 EST


On Tue, 24 Jun 2008, Julia Lawall wrote:
> From: Julia Lawall <julia@xxxxxxx>
>
> As noted by Akinobu Mita in patch b1fceac2b9e04d278316b2faddf276015fc06e3b,
> alloc_bootmem and related functions never return NULL and always return a
> zeroed region of memory. Thus a NULL test or memset after calls to these
> functions is unnecessary.
>
> arch/m68k/mm/sun3mmu.c | 1 -
> 1 file changed, 1 deletion(-)
>
> This was fixed using the following semantic patch.
> (http://www.emn.fr/x-info/coccinelle/)
>
> // <smpl>
> @@
> expression E;
> statement S;
> @@
>
> E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...)
> ... when != E
> (
> - BUG_ON (E == NULL);
> |
> - if (E == NULL) S
> )
>
> @@
> expression E,E1;
> @@
>
> E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...)
> ... when != E
> - memset(E,0,E1);
> // </smpl>
>
> Signed-off-by: Julia Lawall <julia@xxxxxxx>

Acked-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>

(queued for 2.6.27)

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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
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