#endif
#ifdef CONFIG_MEMCG_KMEM
-static int memcg_alloc_cache_params(struct mem_cgroup *memcg,
- struct kmem_cache *s, struct kmem_cache *root_cache)
+void slab_init_memcg_params(struct kmem_cache *s)
{
- size_t size;
+ s->memcg_params.is_root_cache = true;
+ INIT_LIST_HEAD(&s->memcg_params.list);
+ RCU_INIT_POINTER(s->memcg_params.memcg_caches, NULL);
+}
+
+static int init_memcg_params(struct kmem_cache *s,
+ struct mem_cgroup *memcg, struct kmem_cache *root_cache)
+{
+ struct memcg_cache_array *arr;
- if (!memcg_kmem_enabled())
+ if (memcg) {
+ s->memcg_params.is_root_cache = false;
+ s->memcg_params.memcg = memcg;
+ s->memcg_params.root_cache = root_cache;
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);
+ slab_init_memcg_params(s);
- s->memcg_params = kzalloc(size, GFP_KERNEL);
- if (!s->memcg_params)
- return -ENOMEM;
+ if (!memcg_nr_cache_ids)
+ return 0;
- if (memcg) {
- s->memcg_params->memcg = memcg;
- s->memcg_params->root_cache = root_cache;
- } else
- s->memcg_params->is_root_cache = true;
+ arr = kzalloc(sizeof(struct memcg_cache_array) +
+ memcg_nr_cache_ids * sizeof(void *),
+ GFP_KERNEL);
+ if (!arr)
+ return -ENOMEM;
+ RCU_INIT_POINTER(s->memcg_params.memcg_caches, arr);
return 0;
}
-static void memcg_free_cache_params(struct kmem_cache *s)
+static void destroy_memcg_params(struct kmem_cache *s)
{
- kfree(s->memcg_params);
+ if (is_root_cache(s))
+ kfree(rcu_access_pointer(s->memcg_params.memcg_caches));
}
-static int memcg_update_cache_params(struct kmem_cache *s, int num_memcgs)
+static int update_memcg_params(struct kmem_cache *s, int new_array_size)
{
- int size;
- struct memcg_cache_params *new_params, *cur_params;
-
- BUG_ON(!is_root_cache(s));
+ struct memcg_cache_array *old, *new;
- size = offsetof(struct memcg_cache_params, memcg_caches);
- size += num_memcgs * sizeof(void *);
+ if (!is_root_cache(s))
+ return 0;
- new_params = kzalloc(size, GFP_KERNEL);
- if (!new_params)
+ new = kzalloc(sizeof(struct memcg_cache_array) +
+ new_array_size * sizeof(void *), GFP_KERNEL);
+ if (!new)
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);
+ old = rcu_dereference_protected(s->memcg_params.memcg_caches,
+ lockdep_is_held(&slab_mutex));
+ if (old)
+ memcpy(new->entries, old->entries,
+ memcg_nr_cache_ids * sizeof(void *));
+ rcu_assign_pointer(s->memcg_params.memcg_caches, new);
+ if (old)
+ kfree_rcu(old, rcu);
return 0;
}
{
struct kmem_cache *s;
int ret = 0;
- mutex_lock(&slab_mutex);
+ mutex_lock(&slab_mutex);
list_for_each_entry(s, &slab_caches, list) {
- if (!is_root_cache(s))
- continue;
-
- ret = memcg_update_cache_params(s, num_memcgs);
+ ret = update_memcg_params(s, num_memcgs);
/*
* Instead of freeing the memory, we'll just leave the caches
* up to this point in an updated state.
*/
if (ret)
- goto out;
+ break;
}
-
- memcg_update_array_size(num_memcgs);
-out:
mutex_unlock(&slab_mutex);
return ret;
}
#else
-static inline int memcg_alloc_cache_params(struct mem_cgroup *memcg,
- struct kmem_cache *s, struct kmem_cache *root_cache)
+static inline int init_memcg_params(struct kmem_cache *s,
+ struct mem_cgroup *memcg, struct kmem_cache *root_cache)
{
return 0;
}
-static inline void memcg_free_cache_params(struct kmem_cache *s)
+static inline void destroy_memcg_params(struct kmem_cache *s)
{
}
#endif /* CONFIG_MEMCG_KMEM */
s->align = align;
s->ctor = ctor;
- err = memcg_alloc_cache_params(memcg, s, root_cache);
+ err = init_memcg_params(s, memcg, root_cache);
if (err)
goto out_free_cache;
return s;
out_free_cache:
- memcg_free_cache_params(s);
- kfree(s);
+ destroy_memcg_params(s);
+ kmem_cache_free(kmem_cache, s);
goto out;
}
get_online_cpus();
get_online_mems();
+ memcg_get_cache_ids();
mutex_lock(&slab_mutex);
out_unlock:
mutex_unlock(&slab_mutex);
+ memcg_put_cache_ids();
put_online_mems();
put_online_cpus();
}
EXPORT_SYMBOL(kmem_cache_create);
+static int do_kmem_cache_shutdown(struct kmem_cache *s,
+ struct list_head *release, bool *need_rcu_barrier)
+{
+ if (__kmem_cache_shutdown(s) != 0) {
+ printk(KERN_ERR "kmem_cache_destroy %s: "
+ "Slab cache still has objects\n", s->name);
+ dump_stack();
+ return -EBUSY;
+ }
+
+ if (s->flags & SLAB_DESTROY_BY_RCU)
+ *need_rcu_barrier = true;
+
+#ifdef CONFIG_MEMCG_KMEM
+ if (!is_root_cache(s))
+ list_del(&s->memcg_params.list);
+#endif
+ list_move(&s->list, release);
+ return 0;
+}
+
+static void do_kmem_cache_release(struct list_head *release,
+ bool need_rcu_barrier)
+{
+ struct kmem_cache *s, *s2;
+
+ if (need_rcu_barrier)
+ rcu_barrier();
+
+ list_for_each_entry_safe(s, s2, release, list) {
+#ifdef SLAB_SUPPORTS_SYSFS
+ sysfs_slab_remove(s);
+#else
+ slab_kmem_cache_release(s);
+#endif
+ }
+}
+
#ifdef CONFIG_MEMCG_KMEM
/*
* memcg_create_kmem_cache - Create a cache for a memory cgroup.
* @memcg: The memory cgroup the new cache is for.
* @root_cache: The parent of the new cache.
- * @memcg_name: The name of the memory cgroup (used for naming the new cache).
*
* This function attempts to create a kmem cache that will serve allocation
* requests going from @memcg to @root_cache. The new cache inherits properties
* from its parent.
*/
-struct kmem_cache *memcg_create_kmem_cache(struct mem_cgroup *memcg,
- struct kmem_cache *root_cache,
- const char *memcg_name)
+void memcg_create_kmem_cache(struct mem_cgroup *memcg,
+ struct kmem_cache *root_cache)
{
+ static char memcg_name_buf[NAME_MAX + 1]; /* protected by slab_mutex */
+ struct cgroup_subsys_state *css = mem_cgroup_css(memcg);
+ struct memcg_cache_array *arr;
struct kmem_cache *s = NULL;
char *cache_name;
+ int idx;
get_online_cpus();
get_online_mems();
mutex_lock(&slab_mutex);
+ /*
+ * The memory cgroup could have been deactivated while the cache
+ * creation work was pending.
+ */
+ if (!memcg_kmem_is_active(memcg))
+ goto out_unlock;
+
+ idx = memcg_cache_id(memcg);
+ arr = rcu_dereference_protected(root_cache->memcg_params.memcg_caches,
+ lockdep_is_held(&slab_mutex));
+
+ /*
+ * Since per-memcg caches are created asynchronously on first
+ * allocation (see memcg_kmem_get_cache()), several threads can try to
+ * create the same cache, but only one of them may succeed.
+ */
+ if (arr->entries[idx])
+ goto out_unlock;
+
+ cgroup_name(css->cgroup, memcg_name_buf, sizeof(memcg_name_buf));
cache_name = kasprintf(GFP_KERNEL, "%s(%d:%s)", root_cache->name,
- memcg_cache_id(memcg), memcg_name);
+ css->id, memcg_name_buf);
if (!cache_name)
goto out_unlock;
root_cache->size, root_cache->align,
root_cache->flags, root_cache->ctor,
memcg, root_cache);
+ /*
+ * If we could not create a memcg cache, do not complain, because
+ * that's not critical at all as we can always proceed with the root
+ * cache.
+ */
if (IS_ERR(s)) {
kfree(cache_name);
- s = NULL;
+ goto out_unlock;
}
+ list_add(&s->memcg_params.list, &root_cache->memcg_params.list);
+
+ /*
+ * Since readers won't lock (see cache_from_memcg_idx()), we need a
+ * barrier here to ensure nobody will see the kmem_cache partially
+ * initialized.
+ */
+ smp_wmb();
+ arr->entries[idx] = s;
+
out_unlock:
mutex_unlock(&slab_mutex);
put_online_mems();
put_online_cpus();
-
- return s;
}
-static int memcg_cleanup_cache_params(struct kmem_cache *s)
+void memcg_deactivate_kmem_caches(struct mem_cgroup *memcg)
{
- int rc;
+ int idx;
+ struct memcg_cache_array *arr;
+ struct kmem_cache *s, *c;
- if (!s->memcg_params ||
- !s->memcg_params->is_root_cache)
- return 0;
+ idx = memcg_cache_id(memcg);
+
+ get_online_cpus();
+ get_online_mems();
- mutex_unlock(&slab_mutex);
- rc = __memcg_cleanup_cache_params(s);
mutex_lock(&slab_mutex);
+ list_for_each_entry(s, &slab_caches, list) {
+ if (!is_root_cache(s))
+ continue;
+
+ arr = rcu_dereference_protected(s->memcg_params.memcg_caches,
+ lockdep_is_held(&slab_mutex));
+ c = arr->entries[idx];
+ if (!c)
+ continue;
- return rc;
+ __kmem_cache_shrink(c, true);
+ arr->entries[idx] = NULL;
+ }
+ mutex_unlock(&slab_mutex);
+
+ put_online_mems();
+ put_online_cpus();
}
-#else
-static int memcg_cleanup_cache_params(struct kmem_cache *s)
+
+void memcg_destroy_kmem_caches(struct mem_cgroup *memcg)
{
- return 0;
+ LIST_HEAD(release);
+ bool need_rcu_barrier = false;
+ struct kmem_cache *s, *s2;
+
+ get_online_cpus();
+ get_online_mems();
+
+ mutex_lock(&slab_mutex);
+ list_for_each_entry_safe(s, s2, &slab_caches, list) {
+ if (is_root_cache(s) || s->memcg_params.memcg != memcg)
+ continue;
+ /*
+ * The cgroup is about to be freed and therefore has no charges
+ * left. Hence, all its caches must be empty by now.
+ */
+ BUG_ON(do_kmem_cache_shutdown(s, &release, &need_rcu_barrier));
+ }
+ mutex_unlock(&slab_mutex);
+
+ put_online_mems();
+ put_online_cpus();
+
+ do_kmem_cache_release(&release, need_rcu_barrier);
}
#endif /* CONFIG_MEMCG_KMEM */
void slab_kmem_cache_release(struct kmem_cache *s)
{
+ destroy_memcg_params(s);
kfree(s->name);
kmem_cache_free(kmem_cache, s);
}
void kmem_cache_destroy(struct kmem_cache *s)
{
+ struct kmem_cache *c, *c2;
+ LIST_HEAD(release);
+ bool need_rcu_barrier = false;
+ bool busy = false;
+
+ BUG_ON(!is_root_cache(s));
+
get_online_cpus();
get_online_mems();
if (s->refcount)
goto out_unlock;
- if (memcg_cleanup_cache_params(s) != 0)
- goto out_unlock;
-
- if (__kmem_cache_shutdown(s) != 0) {
- printk(KERN_ERR "kmem_cache_destroy %s: "
- "Slab cache still has objects\n", s->name);
- dump_stack();
- goto out_unlock;
+ for_each_memcg_cache_safe(c, c2, s) {
+ if (do_kmem_cache_shutdown(c, &release, &need_rcu_barrier))
+ busy = true;
}
- list_del(&s->list);
-
- mutex_unlock(&slab_mutex);
- if (s->flags & SLAB_DESTROY_BY_RCU)
- rcu_barrier();
-
- memcg_free_cache_params(s);
-#ifdef SLAB_SUPPORTS_SYSFS
- sysfs_slab_remove(s);
-#else
- slab_kmem_cache_release(s);
-#endif
- goto out;
+ if (!busy)
+ do_kmem_cache_shutdown(s, &release, &need_rcu_barrier);
out_unlock:
mutex_unlock(&slab_mutex);
-out:
+
put_online_mems();
put_online_cpus();
+
+ do_kmem_cache_release(&release, need_rcu_barrier);
}
EXPORT_SYMBOL(kmem_cache_destroy);
get_online_cpus();
get_online_mems();
- ret = __kmem_cache_shrink(cachep);
+ ret = __kmem_cache_shrink(cachep, false);
put_online_mems();
put_online_cpus();
return ret;
s->name = name;
s->size = s->object_size = size;
s->align = calculate_alignment(flags, ARCH_KMALLOC_MINALIGN, size);
+
+ slab_init_memcg_params(s);
+
err = __kmem_cache_create(s, flags);
if (err)
{
struct kmem_cache *c;
struct slabinfo sinfo;
- int i;
if (!is_root_cache(s))
return;
- for_each_memcg_cache_index(i) {
- c = cache_from_memcg_idx(s, i);
- if (!c)
- continue;
-
+ for_each_memcg_cache(c, s) {
memset(&sinfo, 0, sizeof(sinfo));
get_slabinfo(c, &sinfo);
if (p == slab_caches.next)
print_slabinfo_header(m);
- if (!is_root_cache(s) && s->memcg_params->memcg == memcg)
+ if (!is_root_cache(s) && s->memcg_params.memcg == memcg)
cache_show(s, m);
return 0;
}
projects / linux-2.6-microblaze.git / blobdiff