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Subject[patch 26/29] arch/m68k/mm/motorola.c: Eliminate NULL test and memset after alloc_bootmem
From: Julia Lawall <julia@diku.dk>

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.

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@diku.dk>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
---
arch/m68k/mm/motorola.c | 1 -
1 file changed, 1 deletion(-)
--- a/arch/m68k/mm/motorola.c
+++ b/arch/m68k/mm/motorola.c
@@ -285,7 +285,6 @@ void __init paging_init(void)
* to a couple of allocated pages
*/
empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
- memset(empty_zero_page, 0, PAGE_SIZE);

/*
* Set up SFC/DFC registers
--
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



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