Commit 8fea4e96 authored by Pekka Enberg's avatar Pekka Enberg Committed by Linus Torvalds
Browse files

[PATCH] slab: object to index mapping cleanup



Clean up the object to index mapping that has been spread around mm/slab.c.
Signed-off-by: default avatarPekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent b50ec7d8
......@@ -609,6 +609,18 @@ static inline struct slab *virt_to_slab(const void *obj)
return page_get_slab(page);
}
static inline void *index_to_obj(struct kmem_cache *cache, struct slab *slab,
unsigned int idx)
{
return slab->s_mem + cache->buffer_size * idx;
}
static inline unsigned int obj_to_index(struct kmem_cache *cache,
struct slab *slab, void *obj)
{
return (unsigned)(obj - slab->s_mem) / cache->buffer_size;
}
/* These are the default caches for kmalloc. Custom caches can have other sizes. */
struct cache_sizes malloc_sizes[] = {
#define CACHE(x) { .cs_size = (x) },
......@@ -1568,18 +1580,18 @@ static void check_poison_obj(struct kmem_cache *cachep, void *objp)
* exist:
*/
struct slab *slabp = virt_to_slab(objp);
int objnr;
unsigned int objnr;
objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size;
objnr = obj_to_index(cachep, slabp, objp);
if (objnr) {
objp = slabp->s_mem + (objnr - 1) * cachep->buffer_size;
objp = index_to_obj(cachep, slabp, objnr - 1);
realobj = (char *)objp + obj_offset(cachep);
printk(KERN_ERR "Prev obj: start=%p, len=%d\n",
realobj, size);
print_objinfo(cachep, objp, 2);
}
if (objnr + 1 < cachep->num) {
objp = slabp->s_mem + (objnr + 1) * cachep->buffer_size;
objp = index_to_obj(cachep, slabp, objnr + 1);
realobj = (char *)objp + obj_offset(cachep);
printk(KERN_ERR "Next obj: start=%p, len=%d\n",
realobj, size);
......@@ -1598,7 +1610,7 @@ static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp)
{
int i;
for (i = 0; i < cachep->num; i++) {
void *objp = slabp->s_mem + cachep->buffer_size * i;
void *objp = index_to_obj(cachep, slabp, i);
if (cachep->flags & SLAB_POISON) {
#ifdef CONFIG_DEBUG_PAGEALLOC
......@@ -1631,7 +1643,7 @@ static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp)
if (cachep->dtor) {
int i;
for (i = 0; i < cachep->num; i++) {
void *objp = slabp->s_mem + cachep->buffer_size * i;
void *objp = index_to_obj(cachep, slabp, i);
(cachep->dtor) (objp, cachep, 0);
}
}
......@@ -2307,7 +2319,7 @@ static void cache_init_objs(struct kmem_cache *cachep,
int i;
for (i = 0; i < cachep->num; i++) {
void *objp = slabp->s_mem + cachep->buffer_size * i;
void *objp = index_to_obj(cachep, slabp, i);
#if DEBUG
/* need to poison the objs? */
if (cachep->flags & SLAB_POISON)
......@@ -2363,7 +2375,7 @@ static void kmem_flagcheck(struct kmem_cache *cachep, gfp_t flags)
static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp, int nodeid)
{
void *objp = slabp->s_mem + (slabp->free * cachep->buffer_size);
void *objp = index_to_obj(cachep, slabp, slabp->free);
kmem_bufctl_t next;
slabp->inuse++;
......@@ -2380,7 +2392,7 @@ static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp, int nod
static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp, void *objp,
int nodeid)
{
unsigned int objnr = (unsigned)(objp-slabp->s_mem) / cachep->buffer_size;
unsigned int objnr = obj_to_index(cachep, slabp, objp);
#if DEBUG
/* Verify that the slab belongs to the intended node */
......@@ -2565,10 +2577,10 @@ static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp,
if (cachep->flags & SLAB_STORE_USER)
*dbg_userword(cachep, objp) = caller;
objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size;
objnr = obj_to_index(cachep, slabp, objp);
BUG_ON(objnr >= cachep->num);
BUG_ON(objp != slabp->s_mem + objnr * cachep->buffer_size);
BUG_ON(objp != index_to_obj(cachep, slabp, objnr));
if (cachep->flags & SLAB_DEBUG_INITIAL) {
/* Need to call the slab's constructor so the
......
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment