slub: free_list() cleanup

free_list looked a bit screwy so here is an attempt to clean it up.

free_list is is only used for freeing partial lists. We do not need to return a
parameter if we decrement nr_partial within the function which allows a
simplification of the whole thing.

The current version modifies nr_partial outside of the list_lock which is
technically not correct. It was only ok because we should be the only user of
this slab cache at this point.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>

diff --git a/mm/slub.c b/mm/slub.c
index 378d3f1..c937233 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2372,25 +2372,21 @@ const char *kmem_cache_name(struct kmem_cache *s)
 EXPORT_SYMBOL(kmem_cache_name);
 
 /*
- * Attempt to free all slabs on a node. Return the number of slabs we
- * were unable to free.
+ * Attempt to free all partial slabs on a node.
  */
-static int free_list(struct kmem_cache *s, struct kmem_cache_node *n,
-                       struct list_head *list)
+static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
 {
-       int slabs_inuse = 0;
        unsigned long flags;
        struct page *page, *h;
 
        spin_lock_irqsave(&n->list_lock, flags);
-       list_for_each_entry_safe(page, h, list, lru)
+       list_for_each_entry_safe(page, h, &n->partial, lru)
                if (!page->inuse) {
                        list_del(&page->lru);
                        discard_slab(s, page);
-               } else
-                       slabs_inuse++;
+                       n->nr_partial--;
+               }
        spin_unlock_irqrestore(&n->list_lock, flags);
-       return slabs_inuse;
 }
 
 /*
@@ -2407,8 +2403,8 @@ static inline int kmem_cache_close(struct kmem_cache *s)
        for_each_node_state(node, N_NORMAL_MEMORY) {
                struct kmem_cache_node *n = get_node(s, node);
 
-               n->nr_partial -= free_list(s, n, &n->partial);
-               if (slabs_node(s, node))
+               free_partial(s, n);
+               if (n->nr_partial || slabs_node(s, node))
                        return 1;
        }
        free_kmem_cache_nodes(s);