slab: introduce helper functions to get/set free object
In the following patches, to get/set free objects from the freelist
is changed so that simple casting doesn't work for it. Therefore,
introduce helper functions.
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
diff --git a/mm/slab.c b/mm/slab.c
index f81176d..878354b 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2548,9 +2548,15 @@
return freelist;
}
-static inline unsigned int *slab_freelist(struct page *page)
+static inline unsigned int get_free_obj(struct page *page, unsigned int idx)
{
- return (unsigned int *)(page->freelist);
+ return ((unsigned int *)page->freelist)[idx];
+}
+
+static inline void set_free_obj(struct page *page,
+ unsigned int idx, unsigned int val)
+{
+ ((unsigned int *)(page->freelist))[idx] = val;
}
static void cache_init_objs(struct kmem_cache *cachep,
@@ -2595,7 +2601,7 @@
if (cachep->ctor)
cachep->ctor(objp);
#endif
- slab_freelist(page)[i] = i;
+ set_free_obj(page, i, i);
}
}
@@ -2614,7 +2620,7 @@
{
void *objp;
- objp = index_to_obj(cachep, page, slab_freelist(page)[page->active]);
+ objp = index_to_obj(cachep, page, get_free_obj(page, page->active));
page->active++;
#if DEBUG
WARN_ON(page_to_nid(virt_to_page(objp)) != nodeid);
@@ -2635,7 +2641,7 @@
/* Verify double free bug */
for (i = page->active; i < cachep->num; i++) {
- if (slab_freelist(page)[i] == objnr) {
+ if (get_free_obj(page, i) == objnr) {
printk(KERN_ERR "slab: double free detected in cache "
"'%s', objp %p\n", cachep->name, objp);
BUG();
@@ -2643,7 +2649,7 @@
}
#endif
page->active--;
- slab_freelist(page)[page->active] = objnr;
+ set_free_obj(page, page->active, objnr);
}
/*
@@ -4216,7 +4222,7 @@
for (j = page->active; j < c->num; j++) {
/* Skip freed item */
- if (slab_freelist(page)[j] == i) {
+ if (get_free_obj(page, j) == i) {
active = false;
break;
}