From: Eric Dumazet <dada1@cosmosbay.com>

Instead of allocating a fix sized array of NR_CPUS pointers for percpu_data,
we can use nr_cpu_ids, which is generally < NR_CPUS.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/percpu.h |    2 +-
 mm/allocpercpu.c       |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff -puN include/linux/percpu.h~percpu-__percpu_alloc_mask-can-dynamically-size-percpu_data include/linux/percpu.h
--- a/include/linux/percpu.h~percpu-__percpu_alloc_mask-can-dynamically-size-percpu_data
+++ a/include/linux/percpu.h
@@ -36,7 +36,7 @@ DECLARE_PER_CPU(cpumask_t, cpu_mask);
 #ifdef CONFIG_SMP
 
 struct percpu_data {
-	void *ptrs[NR_CPUS];
+	void *ptrs[1];
 };
 
 #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
diff -puN mm/allocpercpu.c~percpu-__percpu_alloc_mask-can-dynamically-size-percpu_data mm/allocpercpu.c
--- a/mm/allocpercpu.c~percpu-__percpu_alloc_mask-can-dynamically-size-percpu_data
+++ a/mm/allocpercpu.c
@@ -98,7 +98,7 @@ EXPORT_SYMBOL_GPL(__percpu_populate_mask
  */
 void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask)
 {
-	void *pdata = kzalloc(sizeof(struct percpu_data), gfp);
+	void *pdata = kzalloc(nr_cpu_ids * sizeof(void *), gfp);
 	void *__pdata = __percpu_disguise(pdata);
 
 	if (unlikely(!pdata))
_