From 73367bd8eef4f4eb311005886aaa916013073265 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Fri, 21 May 2010 14:41:35 -0700 Subject: [PATCH] slub: move kmem_cache_node into it's own cacheline This patch is meant to improve the performance of SLUB by moving the local kmem_cache_node lock into it's own cacheline separate from kmem_cache. This is accomplished by simply removing the local_node when NUMA is enabled. On my system with 2 nodes I saw around a 5% performance increase w/ hackbench times dropping from 6.2 seconds to 5.9 seconds on average. I suspect the performance gain would increase as the number of nodes increases, but I do not have the data to currently back that up. Bugzilla-Reference: http://bugzilla.kernel.org/show_bug.cgi?id=15713 Cc: Reported-by: Alex Shi Tested-by: Alex Shi Acked-by: Yanmin Zhang Acked-by: Christoph Lameter Signed-off-by: Alexander Duyck Signed-off-by: Pekka Enberg --- include/linux/slub_def.h | 9 +++------ mm/slub.c | 33 +++++++++++---------------------- 2 files changed, 14 insertions(+), 28 deletions(-) diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h index 55695c8d2f8a..6ac37664e8fe 100644 --- a/include/linux/slub_def.h +++ b/include/linux/slub_def.h @@ -75,12 +75,6 @@ struct kmem_cache { int offset; /* Free pointer offset. */ struct kmem_cache_order_objects oo; - /* - * Avoid an extra cache line for UP, SMP and for the node local to - * struct kmem_cache. - */ - struct kmem_cache_node local_node; - /* Allocation and freeing of slabs */ struct kmem_cache_order_objects max; struct kmem_cache_order_objects min; @@ -102,6 +96,9 @@ struct kmem_cache { */ int remote_node_defrag_ratio; struct kmem_cache_node *node[MAX_NUMNODES]; +#else + /* Avoid an extra cache line for UP */ + struct kmem_cache_node local_node; #endif }; diff --git a/mm/slub.c b/mm/slub.c index e46e3129697d..c2d6e6951f33 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2133,7 +2133,7 @@ static void free_kmem_cache_nodes(struct kmem_cache *s) for_each_node_state(node, N_NORMAL_MEMORY) { struct kmem_cache_node *n = s->node[node]; - if (n && n != &s->local_node) + if (n) kmem_cache_free(kmalloc_caches, n); s->node[node] = NULL; } @@ -2142,33 +2142,22 @@ static void free_kmem_cache_nodes(struct kmem_cache *s) static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags) { int node; - int local_node; - - if (slab_state >= UP && (s < kmalloc_caches || - s >= kmalloc_caches + KMALLOC_CACHES)) - local_node = page_to_nid(virt_to_page(s)); - else - local_node = 0; for_each_node_state(node, N_NORMAL_MEMORY) { struct kmem_cache_node *n; - if (local_node == node) - n = &s->local_node; - else { - if (slab_state == DOWN) { - early_kmem_cache_node_alloc(gfpflags, node); - continue; - } - n = kmem_cache_alloc_node(kmalloc_caches, - gfpflags, node); - - if (!n) { - free_kmem_cache_nodes(s); - return 0; - } + if (slab_state == DOWN) { + early_kmem_cache_node_alloc(gfpflags, node); + continue; + } + n = kmem_cache_alloc_node(kmalloc_caches, + gfpflags, node); + if (!n) { + free_kmem_cache_nodes(s); + return 0; } + s->node[node] = n; init_kmem_cache_node(n, s); } -- 2.39.5