SLUB: allocate smallest object size if the user asks for 0 bytes

Makes SLUB behave like SLAB in this area to avoid issues....

Throw a stack dump to alert people.

At some point the behavior should be switched back.  NULL is no memory as
far as I can tell and if the use asked for 0 bytes then he need to get no
memory.

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>
This commit is contained in:
Christoph Lameter 2007-05-06 14:49:38 -07:00 committed by Linus Torvalds
parent 47bfdc0d5a
commit 614410d589
2 changed files with 7 additions and 3 deletions

View File

@ -80,8 +80,12 @@ extern struct kmem_cache kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
*/
static inline int kmalloc_index(int size)
{
if (size == 0)
return 0;
/*
* We should return 0 if size == 0 but we use the smallest object
* here for SLAB legacy reasons.
*/
WARN_ON_ONCE(size == 0);
if (size > 64 && size <= 96)
return 1;
if (size > 128 && size <= 192)

View File

@ -1979,7 +1979,7 @@ static struct kmem_cache *get_slab(size_t size, gfp_t flags)
{
int index = kmalloc_index(size);
if (!size)
if (!index)
return NULL;
/* Allocation too large? */