From: Julia Lawall <julia@diku.dk>
Date: Sun, 23 Nov 2008 00:48:56 +0000 (+0000)
Subject: powerpc: Eliminate NULL test and memset after alloc_bootmem
X-Git-Tag: v2.6.29-rc1~574^2~97
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=786b32f892dc341b607445bdef29d8e41a840925;p=linux-block.git

powerpc: Eliminate NULL test and memset after alloc_bootmem

As noted by Akinobu Mita in commit b1fceac2 ("x86: remove unnecessary
memset and NULL check after alloc_bootmem()"), 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 = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\|alloc_bootmem_node\|alloc_bootmem_low_pages_node\|alloc_bootmem_pages_node\)(...)
... when != E
(
- BUG_ON (E == NULL);
|
- if (E == NULL) S
)

@@
expression E,E1;
@@

E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\|alloc_bootmem_node\|alloc_bootmem_low_pages_node\|alloc_bootmem_pages_node\)(...)
... when != E
- memset(E,0,E1);
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Paul Mackerras <paulus@samba.org>
---

diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 169d74cef157..93c875ae985a 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -606,8 +606,6 @@ void __init setup_per_cpu_areas(void)
 
 	for_each_possible_cpu(i) {
 		ptr = alloc_bootmem_pages_node(NODE_DATA(cpu_to_node(i)), size);
-		if (!ptr)
-			panic("Cannot allocate cpu data for CPU %d\n", i);
 
 		paca[i].data_offset = ptr - __per_cpu_start;
 		memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);