slub: No need for per node slab counters if !SLUB_DEBUG

[linux-2.6-omap-h63xx.git] / mm / slub.c

diff --git a/mm/slub.c b/mm/slub.c
index f924cffb29e793e8f8713d2071d473df1658cb01..7f8aaa291a4e2b15083a0b5ad8e9beb6978a4346 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -837,6 +837,35 @@ static void remove_full(struct kmem_cache *s, struct page *page)
        spin_unlock(&n->list_lock);
 }
 
+/* Tracking of the number of slabs for debugging purposes */
+static inline unsigned long slabs_node(struct kmem_cache *s, int node)
+{
+       struct kmem_cache_node *n = get_node(s, node);
+
+       return atomic_long_read(&n->nr_slabs);
+}
+
+static inline void inc_slabs_node(struct kmem_cache *s, int node)
+{
+       struct kmem_cache_node *n = get_node(s, node);
+
+       /*
+        * May be called early in order to allocate a slab for the
+        * kmem_cache_node structure. Solve the chicken-egg
+        * dilemma by deferring the increment of the count during
+        * bootstrap (see early_kmem_cache_node_alloc).
+        */
+       if (!NUMA_BUILD || n)
+               atomic_long_inc(&n->nr_slabs);
+}
+static inline void dec_slabs_node(struct kmem_cache *s, int node)
+{
+       struct kmem_cache_node *n = get_node(s, node);
+
+       atomic_long_dec(&n->nr_slabs);
+}
+
+/* Object debug checks for alloc/free paths */
 static void setup_object_debug(struct kmem_cache *s, struct page *page,
                                                                void *object)
 {
@@ -1028,6 +1057,11 @@ static inline unsigned long kmem_cache_flags(unsigned long objsize,
        return flags;
 }
 #define slub_debug 0
+
+static inline unsigned long slabs_node(struct kmem_cache *s, int node)
+                                                       { return 0; }
+static inline void inc_slabs_node(struct kmem_cache *s, int node) {}
+static inline void dec_slabs_node(struct kmem_cache *s, int node) {}
 #endif
 /*
  * Slab allocation and freeing
@@ -1066,7 +1100,6 @@ static void setup_object(struct kmem_cache *s, struct page *page,
 static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
 {
        struct page *page;
-       struct kmem_cache_node *n;
        void *start;
        void *last;
        void *p;
@@ -1078,9 +1111,7 @@ static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
        if (!page)
                goto out;
 
-       n = get_node(s, page_to_nid(page));
-       if (n)
-               atomic_long_inc(&n->nr_slabs);
+       inc_slabs_node(s, page_to_nid(page));
        page->slab = s;
        page->flags |= 1 << PG_slab;
        if (s->flags & (SLAB_DEBUG_FREE | SLAB_RED_ZONE | SLAB_POISON |
@@ -1153,9 +1184,7 @@ static void free_slab(struct kmem_cache *s, struct page *page)
 
 static void discard_slab(struct kmem_cache *s, struct page *page)
 {
-       struct kmem_cache_node *n = get_node(s, page_to_nid(page));
-
-       atomic_long_dec(&n->nr_slabs);
+       dec_slabs_node(s, page_to_nid(page));
        free_slab(s, page);
 }
 
@@ -1894,10 +1923,10 @@ static void init_kmem_cache_cpu(struct kmem_cache *s,
 static void init_kmem_cache_node(struct kmem_cache_node *n)
 {
        n->nr_partial = 0;
-       atomic_long_set(&n->nr_slabs, 0);
        spin_lock_init(&n->list_lock);
        INIT_LIST_HEAD(&n->partial);
 #ifdef CONFIG_SLUB_DEBUG
+       atomic_long_set(&n->nr_slabs, 0);
        INIT_LIST_HEAD(&n->full);
 #endif
 }
@@ -2066,7 +2095,7 @@ static struct kmem_cache_node *early_kmem_cache_node_alloc(gfp_t gfpflags,
        init_tracking(kmalloc_caches, n);
 #endif
        init_kmem_cache_node(n);
-       atomic_long_inc(&n->nr_slabs);
+       inc_slabs_node(kmalloc_caches, node);
 
        /*
         * lockdep requires consistent irq usage for each lock
@@ -2379,7 +2408,7 @@ static inline int kmem_cache_close(struct kmem_cache *s)
                struct kmem_cache_node *n = get_node(s, node);
 
                n->nr_partial -= free_list(s, n, &n->partial);
-               if (atomic_long_read(&n->nr_slabs))
+               if (slabs_node(s, node))
                        return 1;
        }
        free_kmem_cache_nodes(s);
@@ -2801,7 +2830,7 @@ static void slab_mem_offline_callback(void *arg)
                         * and offline_pages() function shoudn't call this
                         * callback. So, we must fail.
                         */
-                       BUG_ON(atomic_long_read(&n->nr_slabs));
+                       BUG_ON(slabs_node(s, offline_node));
 
                        s->node[offline_node] = NULL;
                        kmem_cache_free(kmalloc_caches, n);