mm/sl[aou]b: Move sysfs_slab_add to common

Simplify locking by moving the slab_add_sysfs after all locks have been
dropped. Eases the upcoming move to provide sysfs support for all
allocators.

Reviewed-by: Glauber Costa <glommer@parallels.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

3 files changed, 13 insertions, 13 deletions

diff --git a/mm/slab.h b/mm/slab.h
index 84c28f451d2d..ec7b94429b99 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -39,10 +39,13 @@ struct kmem_cache *__kmem_cache_create(const char *name, size_t size,
 #ifdef CONFIG_SLUB
 struct kmem_cache *__kmem_cache_alias(const char *name, size_t size,
         size_t align, unsigned long flags, void (*ctor)(void *));
+extern int sysfs_slab_add(struct kmem_cache *s);
 #else
 static inline struct kmem_cache *__kmem_cache_alias(const char *name, size_t size,
         size_t align, unsigned long flags, void (*ctor)(void *))
 { return NULL; }
+static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; }
+
 #endif
 
 
diff --git a/mm/slab_common.c b/mm/slab_common.c
index adc42b01b25b..4f722084baed 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -152,6 +152,14 @@ out_locked:
                 return NULL;
         }
 
+        if (s->refcount == 1) {
+                err = sysfs_slab_add(s);
+                if (err)
+                        printk(KERN_WARNING "kmem_cache_create(%s) failed to"
+                                " create sysfs entry. Error %d\n",
+                                        name, err);
+        }
+
         return s;
 }
 EXPORT_SYMBOL(kmem_cache_create);
diff --git a/mm/slub.c b/mm/slub.c
index 64d445e7a27d..8d00fd78df23 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -202,12 +202,10 @@ struct track {
 enum track_item { TRACK_ALLOC, TRACK_FREE };
 
 #ifdef CONFIG_SYSFS
-static int sysfs_slab_add(struct kmem_cache *);
 static int sysfs_slab_alias(struct kmem_cache *, const char *);
 static void sysfs_slab_remove(struct kmem_cache *);
 
 #else
-static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; }
 static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p)
                                                         { return 0; }
 static inline void sysfs_slab_remove(struct kmem_cache *s) { }
@@ -3955,16 +3953,7 @@ struct kmem_cache *__kmem_cache_create(const char *name, size_t size,
         if (s) {
                 if (kmem_cache_open(s, name,
                                 size, align, flags, ctor)) {
-                        int r;
-
-                        mutex_unlock(&slab_mutex);
-                        r = sysfs_slab_add(s);
-                        mutex_lock(&slab_mutex);
-
-                        if (!r)
-                                return s;
-
-                        kmem_cache_close(s);
+                        return s;
                 }
                 kmem_cache_free(kmem_cache, s);
         }
@@ -5258,7 +5247,7 @@ static char *create_unique_id(struct kmem_cache *s)
         return name;
 }
 
-static int sysfs_slab_add(struct kmem_cache *s)
+int sysfs_slab_add(struct kmem_cache *s)
 {
         int err;
         const char *name;