x86/asm/entry: Drop now unused ENABLE_INTERRUPTS_SYSEXIT32
[sfrench/cifs-2.6.git] / mm / slab_common.c
index 6e1e4cf65836cbc5eff3570bd19278a420ec3185..999bb3424d44df71eb9b92d3ae6da75287a391d4 100644 (file)
@@ -106,62 +106,67 @@ static inline 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)
+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;
 }
 
@@ -169,34 +174,28 @@ int memcg_update_all_caches(int num_memcgs)
 {
        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 */
@@ -296,8 +295,8 @@ unsigned long calculate_alignment(unsigned long flags,
 }
 
 static struct kmem_cache *
-do_kmem_cache_create(char *name, size_t object_size, size_t size, size_t align,
-                    unsigned long flags, void (*ctor)(void *),
+do_kmem_cache_create(const char *name, size_t object_size, size_t size,
+                    size_t align, unsigned long flags, void (*ctor)(void *),
                     struct mem_cgroup *memcg, struct kmem_cache *root_cache)
 {
        struct kmem_cache *s;
@@ -314,7 +313,7 @@ do_kmem_cache_create(char *name, size_t object_size, size_t size, size_t align,
        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;
 
@@ -330,7 +329,7 @@ out:
        return s;
 
 out_free_cache:
-       memcg_free_cache_params(s);
+       destroy_memcg_params(s);
        kmem_cache_free(kmem_cache, s);
        goto out;
 }
@@ -364,11 +363,12 @@ kmem_cache_create(const char *name, size_t size, size_t align,
                  unsigned long flags, void (*ctor)(void *))
 {
        struct kmem_cache *s;
-       char *cache_name;
+       const char *cache_name;
        int err;
 
        get_online_cpus();
        get_online_mems();
+       memcg_get_cache_ids();
 
        mutex_lock(&slab_mutex);
 
@@ -390,7 +390,7 @@ kmem_cache_create(const char *name, size_t size, size_t align,
        if (s)
                goto out_unlock;
 
-       cache_name = kstrdup(name, GFP_KERNEL);
+       cache_name = kstrdup_const(name, GFP_KERNEL);
        if (!cache_name) {
                err = -ENOMEM;
                goto out_unlock;
@@ -401,12 +401,13 @@ kmem_cache_create(const char *name, size_t size, size_t align,
                                 flags, ctor, NULL, NULL);
        if (IS_ERR(s)) {
                err = PTR_ERR(s);
-               kfree(cache_name);
+               kfree_const(cache_name);
        }
 
 out_unlock:
        mutex_unlock(&slab_mutex);
 
+       memcg_put_cache_ids();
        put_online_mems();
        put_online_cpus();
 
@@ -439,13 +440,8 @@ static int do_kmem_cache_shutdown(struct kmem_cache *s,
                *need_rcu_barrier = true;
 
 #ifdef CONFIG_MEMCG_KMEM
-       if (!is_root_cache(s)) {
-               struct kmem_cache *root_cache = s->memcg_params->root_cache;
-               int memcg_id = memcg_cache_id(s->memcg_params->memcg);
-
-               BUG_ON(root_cache->memcg_params->memcg_caches[memcg_id] != s);
-               root_cache->memcg_params->memcg_caches[memcg_id] = NULL;
-       }
+       if (!is_root_cache(s))
+               list_del(&s->memcg_params.list);
 #endif
        list_move(&s->list, release);
        return 0;
@@ -482,27 +478,39 @@ 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 */
-       int memcg_id = memcg_cache_id(memcg);
+       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 (cache_from_memcg_idx(root_cache, memcg_id))
+       if (arr->entries[idx])
                goto out_unlock;
 
-       cgroup_name(mem_cgroup_css(memcg)->cgroup,
-                   memcg_name_buf, sizeof(memcg_name_buf));
+       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_buf);
+                              css->id, memcg_name_buf);
        if (!cache_name)
                goto out_unlock;
 
@@ -520,13 +528,15 @@ void memcg_create_kmem_cache(struct mem_cgroup *memcg,
                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();
-       root_cache->memcg_params->memcg_caches[memcg_id] = s;
+       arr->entries[idx] = s;
 
 out_unlock:
        mutex_unlock(&slab_mutex);
@@ -535,6 +545,37 @@ out_unlock:
        put_online_cpus();
 }
 
+void memcg_deactivate_kmem_caches(struct mem_cgroup *memcg)
+{
+       int idx;
+       struct memcg_cache_array *arr;
+       struct kmem_cache *s, *c;
+
+       idx = memcg_cache_id(memcg);
+
+       get_online_cpus();
+       get_online_mems();
+
+       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;
+
+               __kmem_cache_shrink(c, true);
+               arr->entries[idx] = NULL;
+       }
+       mutex_unlock(&slab_mutex);
+
+       put_online_mems();
+       put_online_cpus();
+}
+
 void memcg_destroy_kmem_caches(struct mem_cgroup *memcg)
 {
        LIST_HEAD(release);
@@ -546,7 +587,7 @@ void memcg_destroy_kmem_caches(struct mem_cgroup *memcg)
 
        mutex_lock(&slab_mutex);
        list_for_each_entry_safe(s, s2, &slab_caches, list) {
-               if (is_root_cache(s) || s->memcg_params->memcg != memcg)
+               if (is_root_cache(s) || s->memcg_params.memcg != memcg)
                        continue;
                /*
                 * The cgroup is about to be freed and therefore has no charges
@@ -565,18 +606,20 @@ void memcg_destroy_kmem_caches(struct mem_cgroup *memcg)
 
 void slab_kmem_cache_release(struct kmem_cache *s)
 {
-       memcg_free_cache_params(s);
-       kfree(s->name);
+       destroy_memcg_params(s);
+       kfree_const(s->name);
        kmem_cache_free(kmem_cache, s);
 }
 
 void kmem_cache_destroy(struct kmem_cache *s)
 {
-       int i;
+       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();
 
@@ -586,10 +629,8 @@ void kmem_cache_destroy(struct kmem_cache *s)
        if (s->refcount)
                goto out_unlock;
 
-       for_each_memcg_cache_index(i) {
-               struct kmem_cache *c = cache_from_memcg_idx(s, i);
-
-               if (c && do_kmem_cache_shutdown(c, &release, &need_rcu_barrier))
+       for_each_memcg_cache_safe(c, c2, s) {
+               if (do_kmem_cache_shutdown(c, &release, &need_rcu_barrier))
                        busy = true;
        }
 
@@ -619,7 +660,7 @@ int kmem_cache_shrink(struct kmem_cache *cachep)
 
        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;
@@ -641,6 +682,9 @@ void __init create_boot_cache(struct kmem_cache *s, const char *name, size_t siz
        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)
@@ -854,6 +898,7 @@ void *kmalloc_order(size_t size, gfp_t flags, unsigned int order)
        page = alloc_kmem_pages(flags, order);
        ret = page ? page_address(page) : NULL;
        kmemleak_alloc(ret, size, 1, flags);
+       kasan_kmalloc_large(ret, size);
        return ret;
 }
 EXPORT_SYMBOL(kmalloc_order);
@@ -920,16 +965,11 @@ memcg_accumulate_slabinfo(struct kmem_cache *s, struct slabinfo *info)
 {
        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);
 
@@ -981,7 +1021,7 @@ int memcg_slab_show(struct seq_file *m, void *p)
 
        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;
 }
@@ -1038,8 +1078,10 @@ static __always_inline void *__do_krealloc(const void *p, size_t new_size,
        if (p)
                ks = ksize(p);
 
-       if (ks >= new_size)
+       if (ks >= new_size) {
+               kasan_krealloc((void *)p, new_size);
                return (void *)p;
+       }
 
        ret = kmalloc_track_caller(new_size, flags);
        if (ret && p)