Subject: [PATCH] arch/m68k/mm/motorola.c: Eliminate NULL test and memset after alloc_bootmem From: Julia Lawall 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/) // @@ 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); // Signed-off-by: Julia Lawall Signed-off-by: Geert Uytterhoeven --- 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