Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 16025177 authored by Joonsoo Kim's avatar Joonsoo Kim Committed by Pekka Enberg
Browse files

slab: remove kmem_bufctl_t 



Now, we changed the management method of free objects of the slab and
there is no need to use special value, BUFCTL_END, BUFCTL_FREE and
BUFCTL_ACTIVE. So remove them.

Acked-by: default avatarAndi Kleen <ak@linux.intel.com>
Signed-off-by: default avatarJoonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: default avatarPekka Enberg <penberg@iki.fi>
parent b1cb0982

mm/slab.c

+11 −31
Original line number Diff line number Diff line
@@ -163,27 +163,7 @@ 
 */

static bool pfmemalloc_active __read_mostly;



/*

 * kmem_bufctl_t:

 *

 * Bufctl's are used for linking objs within a slab

 * linked offsets.

 *

 * This implementation relies on "struct page" for locating the cache &

 * slab an object belongs to.

 * This allows the bufctl structure to be small (one int), but limits

 * the number of objects a slab (not a cache) can contain when off-slab

 * bufctls are used. The limit is the size of the largest general cache

 * that does not use off-slab slabs.

 * For 32bit archs with 4 kB pages, is this 56.

 * This is not serious, as it is only for large objects, when it is unwise

 * to have too many per slab.

 * Note: This limit can be raised by introducing a general cache whose size

 * is less than 512 (PAGE_SIZE<<3), but greater than 256.

 */



typedef unsigned int kmem_bufctl_t;

#define	SLAB_LIMIT	(((kmem_bufctl_t)(~0U))-3)

#define	SLAB_LIMIT	(((unsigned int)(~0U))-1)



/*

 * struct slab
@@ -197,7 +177,7 @@ struct slab { 
		struct list_head list;

		void *s_mem;		/* including colour offset */

		unsigned int inuse;	/* num of objs active in slab */

		kmem_bufctl_t free;

		unsigned int free;

	};

};
@@ -613,7 +593,7 @@ static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) 


static size_t slab_mgmt_size(size_t nr_objs, size_t align)

{

	return ALIGN(sizeof(struct slab)+nr_objs*sizeof(kmem_bufctl_t), align);

	return ALIGN(sizeof(struct slab)+nr_objs*sizeof(unsigned int), align);

}



/*
@@ -633,7 +613,7 @@ static void cache_estimate(unsigned long gfporder, size_t buffer_size, 
	 * slab is used for:

	 *

	 * - The struct slab

	 * - One kmem_bufctl_t for each object

	 * - One unsigned int for each object

	 * - Padding to respect alignment of @align

	 * - @buffer_size bytes for each object

	 *
@@ -658,7 +638,7 @@ static void cache_estimate(unsigned long gfporder, size_t buffer_size, 
		 * into account.

		 */

		nr_objs = (slab_size - sizeof(struct slab)) /

			  (buffer_size + sizeof(kmem_bufctl_t));

			  (buffer_size + sizeof(unsigned int));



		/*

		 * This calculated number will be either the right
@@ -2068,7 +2048,7 @@ static size_t calculate_slab_order(struct kmem_cache *cachep, 
			 * looping condition in cache_grow().

			 */

			offslab_limit = size - sizeof(struct slab);

			offslab_limit /= sizeof(kmem_bufctl_t);

			offslab_limit /= sizeof(unsigned int);



 			if (num > offslab_limit)

				break;
@@ -2309,7 +2289,7 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags) 
	if (!cachep->num)

		return -E2BIG;



	slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t)

	slab_size = ALIGN(cachep->num * sizeof(unsigned int)

			  + sizeof(struct slab), cachep->align);



	/*
@@ -2324,7 +2304,7 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags) 
	if (flags & CFLGS_OFF_SLAB) {

		/* really off slab. No need for manual alignment */

		slab_size =

		    cachep->num * sizeof(kmem_bufctl_t) + sizeof(struct slab);

		    cachep->num * sizeof(unsigned int) + sizeof(struct slab);



#ifdef CONFIG_PAGE_POISONING

		/* If we're going to use the generic kernel_map_pages()
@@ -2603,9 +2583,9 @@ static struct slab *alloc_slabmgmt(struct kmem_cache *cachep, 
	return slabp;

}



static inline kmem_bufctl_t *slab_bufctl(struct slab *slabp)

static inline unsigned int *slab_bufctl(struct slab *slabp)

{

	return (kmem_bufctl_t *) (slabp + 1);

	return (unsigned int *) (slabp + 1);

}



static void cache_init_objs(struct kmem_cache *cachep,
@@ -2684,7 +2664,7 @@ static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp, 
{

	unsigned int objnr = obj_to_index(cachep, slabp, objp);

#if DEBUG

	kmem_bufctl_t i;

	unsigned int i;



	/* Verify that the slab belongs to the intended node */

	WARN_ON(page_to_nid(virt_to_page(objp)) != nodeid);