DEFINE_MUTEX(slab_mutex);
struct kmem_cache *kmem_cache;
+/*
+ * Set of flags that will prevent slab merging
+ */
+#define SLAB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
+ SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \
+ SLAB_FAILSLAB)
+
+#define SLAB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \
+ SLAB_CACHE_DMA | SLAB_NOTRACK)
+
+/*
+ * Merge control. If this is set then no merging of slab caches will occur.
+ * (Could be removed. This was introduced to pacify the merge skeptics.)
+ */
+static int slab_nomerge;
+
+static int __init setup_slab_nomerge(char *str)
+{
+ slab_nomerge = 1;
+ return 1;
+}
+
+#ifdef CONFIG_SLUB
+__setup_param("slub_nomerge", slub_nomerge, setup_slab_nomerge, 0);
+#endif
+
+__setup("slab_nomerge", setup_slab_nomerge);
+
+/*
+ * Determine the size of a slab object
+ */
+unsigned int kmem_cache_size(struct kmem_cache *s)
+{
+ return s->object_size;
+}
+EXPORT_SYMBOL(kmem_cache_size);
+
#ifdef CONFIG_DEBUG_VM
static int kmem_cache_sanity_check(const char *name, size_t size)
{
#endif
#ifdef CONFIG_MEMCG_KMEM
+static int memcg_alloc_cache_params(struct mem_cgroup *memcg,
+ struct kmem_cache *s, struct kmem_cache *root_cache)
+{
+ size_t size;
+
+ if (!memcg_kmem_enabled())
+ return 0;
+
+ if (!memcg) {
+ size = offsetof(struct memcg_cache_params, memcg_caches);
+ size += memcg_limited_groups_array_size * sizeof(void *);
+ } else
+ size = sizeof(struct memcg_cache_params);
+
+ s->memcg_params = kzalloc(size, GFP_KERNEL);
+ if (!s->memcg_params)
+ return -ENOMEM;
+
+ if (memcg) {
+ s->memcg_params->memcg = memcg;
+ s->memcg_params->root_cache = root_cache;
+ } else
+ s->memcg_params->is_root_cache = true;
+
+ return 0;
+}
+
+static void memcg_free_cache_params(struct kmem_cache *s)
+{
+ kfree(s->memcg_params);
+}
+
+static int memcg_update_cache_params(struct kmem_cache *s, int num_memcgs)
+{
+ int size;
+ struct memcg_cache_params *new_params, *cur_params;
+
+ BUG_ON(!is_root_cache(s));
+
+ size = offsetof(struct memcg_cache_params, memcg_caches);
+ size += num_memcgs * sizeof(void *);
+
+ new_params = kzalloc(size, GFP_KERNEL);
+ if (!new_params)
+ return -ENOMEM;
+
+ cur_params = s->memcg_params;
+ memcpy(new_params->memcg_caches, cur_params->memcg_caches,
+ memcg_limited_groups_array_size * sizeof(void *));
+
+ new_params->is_root_cache = true;
+
+ rcu_assign_pointer(s->memcg_params, new_params);
+ if (cur_params)
+ kfree_rcu(cur_params, rcu_head);
+
+ return 0;
+}
+
int memcg_update_all_caches(int num_memcgs)
{
struct kmem_cache *s;
if (!is_root_cache(s))
continue;
- ret = memcg_update_cache_size(s, num_memcgs);
+ ret = memcg_update_cache_params(s, num_memcgs);
/*
- * See comment in memcontrol.c, memcg_update_cache_size:
* Instead of freeing the memory, we'll just leave the caches
* up to this point in an updated state.
*/
mutex_unlock(&slab_mutex);
return ret;
}
-#endif
+#else
+static inline int memcg_alloc_cache_params(struct mem_cgroup *memcg,
+ struct kmem_cache *s, struct kmem_cache *root_cache)
+{
+ return 0;
+}
+
+static inline void memcg_free_cache_params(struct kmem_cache *s)
+{
+}
+#endif /* CONFIG_MEMCG_KMEM */
+
+/*
+ * Find a mergeable slab cache
+ */
+int slab_unmergeable(struct kmem_cache *s)
+{
+ if (slab_nomerge || (s->flags & SLAB_NEVER_MERGE))
+ return 1;
+
+ if (!is_root_cache(s))
+ return 1;
+
+ if (s->ctor)
+ return 1;
+
+ /*
+ * We may have set a slab to be unmergeable during bootstrap.
+ */
+ if (s->refcount < 0)
+ return 1;
+
+ return 0;
+}
+
+struct kmem_cache *find_mergeable(size_t size, size_t align,
+ unsigned long flags, const char *name, void (*ctor)(void *))
+{
+ struct kmem_cache *s;
+
+ if (slab_nomerge || (flags & SLAB_NEVER_MERGE))
+ return NULL;
+
+ if (ctor)
+ return NULL;
+
+ size = ALIGN(size, sizeof(void *));
+ align = calculate_alignment(flags, align, size);
+ size = ALIGN(size, align);
+ flags = kmem_cache_flags(size, flags, name, NULL);
+
+ list_for_each_entry(s, &slab_caches, list) {
+ if (slab_unmergeable(s))
+ continue;
+
+ if (size > s->size)
+ continue;
+
+ if ((flags & SLAB_MERGE_SAME) != (s->flags & SLAB_MERGE_SAME))
+ continue;
+ /*
+ * Check if alignment is compatible.
+ * Courtesy of Adrian Drzewiecki
+ */
+ if ((s->size & ~(align - 1)) != s->size)
+ continue;
+
+ if (s->size - size >= sizeof(void *))
+ continue;
+
+ return s;
+ }
+ return NULL;
+}
/*
* Figure out what the alignment of the objects will be given a set of
mutex_lock(&slab_mutex);
err = kmem_cache_sanity_check(name, size);
- if (err)
+ if (err) {
+ s = NULL; /* suppress uninit var warning */
goto out_unlock;
+ }
/*
* Some allocators will constraint the set of valid flags to a subset
projects / cascardo / linux.git / blobdiff