slub: get_map() function to establish map of free objects in a slab

The bit map of free objects in a slab page is determined in various functions
if debugging is enabled.

Provide a common function for that purpose.

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
This commit is contained in:
Christoph Lameter 2011-04-15 14:48:13 -05:00 committed by Pekka Enberg
parent 33de04ec4c
commit 5f80b13ae4

View File

@ -271,10 +271,6 @@ static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp)
for (__p = (__addr); __p < (__addr) + (__objects) * (__s)->size;\
__p += (__s)->size)
/* Scan freelist */
#define for_each_free_object(__p, __s, __free) \
for (__p = (__free); __p; __p = get_freepointer((__s), __p))
/* Determine object index from a given position */
static inline int slab_index(void *p, struct kmem_cache *s, void *addr)
{
@ -330,6 +326,21 @@ static inline int oo_objects(struct kmem_cache_order_objects x)
return x.x & OO_MASK;
}
/*
* Determine a map of object in use on a page.
*
* Slab lock or node listlock must be held to guarantee that the page does
* not vanish from under us.
*/
static void get_map(struct kmem_cache *s, struct page *page, unsigned long *map)
{
void *p;
void *addr = page_address(page);
for (p = page->freelist; p; p = get_freepointer(s, p))
set_bit(slab_index(p, s, addr), map);
}
#ifdef CONFIG_SLUB_DEBUG
/*
* Debug settings:
@ -2673,9 +2684,8 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
return;
slab_err(s, page, "%s", text);
slab_lock(page);
for_each_free_object(p, s, page->freelist)
set_bit(slab_index(p, s, addr), map);
get_map(s, page, map);
for_each_object(p, s, addr, page->objects) {
if (!test_bit(slab_index(p, s, addr), map)) {
@ -3610,10 +3620,11 @@ static int validate_slab(struct kmem_cache *s, struct page *page,
/* Now we know that a valid freelist exists */
bitmap_zero(map, page->objects);
for_each_free_object(p, s, page->freelist) {
set_bit(slab_index(p, s, addr), map);
if (!check_object(s, page, p, SLUB_RED_INACTIVE))
return 0;
get_map(s, page, map);
for_each_object(p, s, addr, page->objects) {
if (test_bit(slab_index(p, s, addr), map))
if (!check_object(s, page, p, SLUB_RED_INACTIVE))
return 0;
}
for_each_object(p, s, addr, page->objects)
@ -3821,8 +3832,7 @@ static void process_slab(struct loc_track *t, struct kmem_cache *s,
void *p;
bitmap_zero(map, page->objects);
for_each_free_object(p, s, page->freelist)
set_bit(slab_index(p, s, addr), map);
get_map(s, page, map);
for_each_object(p, s, addr, page->objects)
if (!test_bit(slab_index(p, s, addr), map))