[SLAB] Introduce kmem_cache_name

This is for use with slab users that pass a dynamically allocated slab name in
kmem_cache_create, so that before destroying the slab one can retrieve the name
and free its memory.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/mm/slab.c b/mm/slab.c
index 8407426..c78d343 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2620,6 +2620,12 @@
 }
 EXPORT_SYMBOL(kmem_cache_size);
 
+const char *kmem_cache_name(kmem_cache_t *cachep)
+{
+	return cachep->name;
+}
+EXPORT_SYMBOL_GPL(kmem_cache_name);
+
 struct ccupdate_struct {
 	kmem_cache_t *cachep;
 	struct array_cache *new[NR_CPUS];