2007-06-18 09:48:20

by cheng renquan

Subject: [PATCH] the memset operation on a automatic array variable should be optimized out by data initialization

Is there some comments on this?

Signed-Off-By: Denis Cheng <[email protected]>

--

--- arch/x86_64/mm/init.c.orig 2007-06-07 10:08:04.000000000 +0800
+++ arch/x86_64/mm/init.c 2007-06-18 14:43:15.000000000 +0800
@@ -406,8 +406,7 @@ void __cpuinit zap_low_mappings(int cpu)
#ifndef CONFIG_NUMA
void __init paging_init(void)
{
- unsigned long max_zone_pfns[MAX_NR_ZONES];
- memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
+ unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
max_zone_pfns[ZONE_NORMAL] = end_pfn;