slab common: add functions for kmem_cache_node access

The patchset provides two new functions in mm/slab.h and modifies SLAB
and SLUB to use these.  The kmem_cache_node structure is shared between
both allocators and the use of common accessors will allow us to move
more code into slab_common.c in the future.

This patch (of 3):

These functions allow to eliminate repeatedly used code in both SLAB and
SLUB and also allow for the insertion of debugging code that may be
needed in the development process.

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

diff --git a/mm/slab.h b/mm/slab.h
index 961a3fb1f5a2c69454e123e5a2d7c34b652c2a1c..3f9766e393a3b9b83ca01d5908ba25428e736415 100644 (file)
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -262,7 +262,7 @@ static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
 }
 #endif
 
-
+#ifndef CONFIG_SLOB
 /*
  * The slab lists for all objects.
  */
@@ -294,5 +294,20 @@ struct kmem_cache_node {
 
 };
 
+static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
+{
+       return s->node[node];
+}
+
+/*
+ * Iterator over all nodes. The body will be executed for each node that has
+ * a kmem_cache_node structure allocated (which is true for all online nodes)
+ */
+#define for_each_kmem_cache_node(__s, __node, __n) \
+       for (__node = 0; __n = get_node(__s, __node), __node < nr_node_ids; __node++) \
+                if (__n)
+
+#endif
+
 void *slab_next(struct seq_file *m, void *p, loff_t *pos);
 void slab_stop(struct seq_file *m, void *p);

diff --git a/mm/slub.c b/mm/slub.c
index 73004808537ea841e05c85e0b68312ea645eb114..2569802aa7cc2f210b72ba2ac13e619e4656f0ec 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -233,11 +233,6 @@ static inline void stat(const struct kmem_cache *s, enum stat_item si)
  *                     Core slab cache functions
  *******************************************************************/
 
-static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
-{
-       return s->node[node];
-}
-
 /* Verify that a pointer has an address that is valid within a slab page */
 static inline int check_valid_pointer(struct kmem_cache *s,
                                struct page *page, const void *object)