From 3fe5f54e696e7af4e38fbb7ba6079dcc22875bce Mon Sep 17 00:00:00 2001 From: Manfred Spraul Date: Tue, 19 Oct 2004 18:40:18 -0700 Subject: [PATCH] slab: reduce fragmentation due to kmem_cache_alloc_node Attached is a patch that fixes the fragmentation that Badri noticed with kmem_cache_alloc_node. kmem_cache_alloc_node tries to allocate memory from a given node. The current implementation contains two bugs: - the node aware code was used even for !CONFIG_NUMA systems. Fix: inline function that redefines kmem_cache_alloc_node as kmem_cache_alloc for !CONFIG_NUMA. - the code always allocated a new slab for each new allocation. This caused severe fragmentation. Fix: walk the slabp lists and search for a matching page instead of allocating a new page. - the patch also adds a new statistics field for node-local allocs. They should be rare - the codepath is quite slow, especially compared to the normal kmem_cache_alloc. Signed-Off-By: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/slab.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include') diff --git a/include/linux/slab.h b/include/linux/slab.h index e51014cb24a0..7c81a7863b99 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -61,7 +61,14 @@ extern kmem_cache_t *kmem_cache_create(const char *, size_t, size_t, unsigned lo extern int kmem_cache_destroy(kmem_cache_t *); extern int kmem_cache_shrink(kmem_cache_t *); extern void *kmem_cache_alloc(kmem_cache_t *, int); +#ifdef CONFIG_NUMA extern void *kmem_cache_alloc_node(kmem_cache_t *, int); +#else +static inline void *kmem_cache_alloc_node(kmem_cache_t *cachep, int node) +{ + return kmem_cache_alloc(cachep, GFP_KERNEL); +} +#endif extern void kmem_cache_free(kmem_cache_t *, void *); extern unsigned int kmem_cache_size(kmem_cache_t *); -- cgit v1.2.3