Avoid double memclear() in SLOB/SLUB

Both slob and slub react to __GFP_ZERO by clearing the allocation, which
means that passing the GFP_ZERO bit down to the page allocator is just
wasteful and pointless.

Acked-by: Matt Mackall <mpm@selenic.com>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/slob.c b/mm/slob.c
index ee2ef8a..773a7aa 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -330,7 +330,7 @@
 
 	/* Not enough space: must allocate a new page */
 	if (!b) {
-		b = slob_new_page(gfp, 0, node);
+		b = slob_new_page(gfp & ~__GFP_ZERO, 0, node);
 		if (!b)
 			return 0;
 		sp = (struct slob_page *)virt_to_page(b);