slab: Make allocations with GFP_ZERO slightly more efficient
Use the likely mechanism already around valid
pointer tests to better choose when to memset
to 0 allocations with __GFP_ZERO
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
diff --git a/mm/slab.c b/mm/slab.c
index 54eba8a..8347d80 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3278,11 +3278,11 @@
kmemleak_alloc_recursive(ptr, cachep->object_size, 1, cachep->flags,
flags);
- if (likely(ptr))
+ if (likely(ptr)) {
kmemcheck_slab_alloc(cachep, flags, ptr, cachep->object_size);
-
- if (unlikely((flags & __GFP_ZERO) && ptr))
- memset(ptr, 0, cachep->object_size);
+ if (unlikely(flags & __GFP_ZERO))
+ memset(ptr, 0, cachep->object_size);
+ }
return ptr;
}
@@ -3343,11 +3343,11 @@
flags);
prefetchw(objp);
- if (likely(objp))
+ if (likely(objp)) {
kmemcheck_slab_alloc(cachep, flags, objp, cachep->object_size);
-
- if (unlikely((flags & __GFP_ZERO) && objp))
- memset(objp, 0, cachep->object_size);
+ if (unlikely(flags & __GFP_ZERO))
+ memset(objp, 0, cachep->object_size);
+ }
return objp;
}