mm/slab_common: commonize slab merge logic

Slab merge is good feature to reduce fragmentation.  Now, it is only
applied to SLUB, but, it would be good to apply it to SLAB.  This patch is
preparation step to apply slab merge to SLAB by commonizing slab merge
logic.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/mm/slab.h b/mm/slab.h
index 6599f2084e80..c44d28b60609 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -88,15 +88,30 @@ extern void create_boot_cache(struct kmem_cache *, const char *name,
                         size_t size, unsigned long flags);
 
 struct mem_cgroup;
+
+int slab_unmergeable(struct kmem_cache *s);
+struct kmem_cache *find_mergeable(size_t size, size_t align,
+                unsigned long flags, const char *name, void (*ctor)(void *));
 #ifdef CONFIG_SLUB
 struct kmem_cache *
 __kmem_cache_alias(const char *name, size_t size, size_t align,
                    unsigned long flags, void (*ctor)(void *));
+
+unsigned long kmem_cache_flags(unsigned long object_size,
+        unsigned long flags, const char *name,
+        void (*ctor)(void *));
 #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 unsigned long kmem_cache_flags(unsigned long object_size,
+        unsigned long flags, const char *name,
+        void (*ctor)(void *))
+{
+        return flags;
+}
 #endif