Commit 25c4f304 authored by Joonsoo Kim's avatar Joonsoo Kim Committed by Linus Torvalds
Browse files

mm/slab: factor out unlikely part of cache_free_alien() 



cache_free_alien() is rarely used function when node mismatch.  But, it is
defined with inline attribute so it is inlined to __cache_free() which is
core free function of slab allocator.  It uselessly makes
kmem_cache_free()/kfree() functions large.  What we really need to inline
is just checking node match so this patch factor out other parts of
cache_free_alien() to reduce code size of kmem_cache_free()/ kfree().

<Before>
nm -S mm/slab.o | grep -e "T kfree" -e "T kmem_cache_free"
00000000000011e0 0000000000000228 T kfree
0000000000000670 0000000000000216 T kmem_cache_free

<After>
nm -S mm/slab.o | grep -e "T kfree" -e "T kmem_cache_free"
0000000000001110 00000000000001b5 T kfree
0000000000000750 0000000000000181 T kmem_cache_free

You can see slightly reduced size of text: 0x228->0x1b5, 0x216->0x181.

Signed-off-by: default avatarJoonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d3aec344

mm/slab.c

+21 −17
Original line number Diff line number Diff line
@@ -984,46 +984,50 @@ static void drain_alien_cache(struct kmem_cache *cachep, 
	}

}



static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)

static int __cache_free_alien(struct kmem_cache *cachep, void *objp,

				int node, int page_node)

{

	int nodeid = page_to_nid(virt_to_page(objp));

	struct kmem_cache_node *n;

	struct alien_cache *alien = NULL;

	struct array_cache *ac;

	int node;

	LIST_HEAD(list);



	node = numa_mem_id();



	/*

	 * Make sure we are not freeing a object from another node to the array

	 * cache on this cpu.

	 */

	if (likely(nodeid == node))

		return 0;



	n = get_node(cachep, node);

	STATS_INC_NODEFREES(cachep);

	if (n->alien && n->alien[nodeid]) {

		alien = n->alien[nodeid];

	if (n->alien && n->alien[page_node]) {

		alien = n->alien[page_node];

		ac = &alien->ac;

		spin_lock(&alien->lock);

		if (unlikely(ac->avail == ac->limit)) {

			STATS_INC_ACOVERFLOW(cachep);

			__drain_alien_cache(cachep, ac, nodeid, &list);

			__drain_alien_cache(cachep, ac, page_node, &list);

		}

		ac_put_obj(cachep, ac, objp);

		spin_unlock(&alien->lock);

		slabs_destroy(cachep, &list);

	} else {

		n = get_node(cachep, nodeid);

		n = get_node(cachep, page_node);

		spin_lock(&n->list_lock);

		free_block(cachep, &objp, 1, nodeid, &list);

		free_block(cachep, &objp, 1, page_node, &list);

		spin_unlock(&n->list_lock);

		slabs_destroy(cachep, &list);

	}

	return 1;

}



static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)

{

	int page_node = page_to_nid(virt_to_page(objp));

	int node = numa_mem_id();

	/*

	 * Make sure we are not freeing a object from another node to the array

	 * cache on this cpu.

	 */

	if (likely(node == page_node))

		return 0;



	return __cache_free_alien(cachep, objp, node, page_node);

}

#endif



/*

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