{slub, slob}: use unlikely() for kfree(ZERO_OR_NULL_PTR) check

Considering kfree(NULL) would normally occur only in error paths and
kfree(ZERO_SIZE_PTR) is uncommon as well, so let's use unlikely() for the
condition check in SLUB's and SLOB's kfree() to optimize for the common
case.  SLAB has this already.

Signed-off-by: Satyam Sharma <satyam@infradead.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Satyam Sharma 2007-10-16 01:24:44 -07:00 committed by Linus Torvalds
parent c92ff1bde0
commit 2408c55037
2 changed files with 7 additions and 7 deletions

View File

@ -360,7 +360,7 @@ static void slob_free(void *block, int size)
slobidx_t units;
unsigned long flags;
if (ZERO_OR_NULL_PTR(block))
if (unlikely(ZERO_OR_NULL_PTR(block)))
return;
BUG_ON(!size);
@ -466,7 +466,7 @@ void kfree(const void *block)
{
struct slob_page *sp;
if (ZERO_OR_NULL_PTR(block))
if (unlikely(ZERO_OR_NULL_PTR(block)))
return;
sp = (struct slob_page *)virt_to_page(block);
@ -484,7 +484,7 @@ size_t ksize(const void *block)
{
struct slob_page *sp;
if (ZERO_OR_NULL_PTR(block))
if (unlikely(ZERO_OR_NULL_PTR(block)))
return 0;
sp = (struct slob_page *)virt_to_page(block);

View File

@ -2449,7 +2449,7 @@ size_t ksize(const void *object)
struct page *page;
struct kmem_cache *s;
if (ZERO_OR_NULL_PTR(object))
if (unlikely(ZERO_OR_NULL_PTR(object)))
return 0;
page = get_object_page(object);
@ -2483,7 +2483,7 @@ void kfree(const void *x)
{
struct page *page;
if (ZERO_OR_NULL_PTR(x))
if (unlikely(ZERO_OR_NULL_PTR(x)))
return;
page = virt_to_head_page(x);
@ -2800,7 +2800,7 @@ void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, void *caller)
get_order(size));
s = get_slab(size, gfpflags);
if (ZERO_OR_NULL_PTR(s))
if (unlikely(ZERO_OR_NULL_PTR(s)))
return s;
return slab_alloc(s, gfpflags, -1, caller);
@ -2816,7 +2816,7 @@ void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
get_order(size));
s = get_slab(size, gfpflags);
if (ZERO_OR_NULL_PTR(s))
if (unlikely(ZERO_OR_NULL_PTR(s)))
return s;
return slab_alloc(s, gfpflags, node, caller);