Slab allocators: Replace explicit zeroing with __GFP_ZERO

kmalloc_node() and kmem_cache_alloc_node() were not available in a zeroing
variant in the past.  But with __GFP_ZERO it is possible now to do zeroing
while allocating.

Use __GFP_ZERO to remove the explicit clearing of memory via memset whereever
we can.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/allocpercpu.c b/mm/allocpercpu.c
index b2486cf..00b0262 100644
--- a/mm/allocpercpu.c
+++ b/mm/allocpercpu.c
@@ -53,12 +53,9 @@
 	int node = cpu_to_node(cpu);
 
 	BUG_ON(pdata->ptrs[cpu]);
-	if (node_online(node)) {
-		/* FIXME: kzalloc_node(size, gfp, node) */
-		pdata->ptrs[cpu] = kmalloc_node(size, gfp, node);
-		if (pdata->ptrs[cpu])
-			memset(pdata->ptrs[cpu], 0, size);
-	} else
+	if (node_online(node))
+		pdata->ptrs[cpu] = kmalloc_node(size, gfp|__GFP_ZERO, node);
+	else
 		pdata->ptrs[cpu] = kzalloc(size, gfp);
 	return pdata->ptrs[cpu];
 }