FS-Cache: Release page->private after failed readahead

[safe/jmp/linux-2.6] / mm / page_cgroup.c

diff --git a/mm/page_cgroup.c b/mm/page_cgroup.c
index 7006a11..791905c 100644 (file)
--- a/mm/page_cgroup.c
+++ b/mm/page_cgroup.c
@@ -114,7 +114,8 @@ static int __init_refok init_section_page_cgroup(unsigned long pfn)
                nid = page_to_nid(pfn_to_page(pfn));
                table_size = sizeof(struct page_cgroup) * PAGES_PER_SECTION;
                if (slab_is_available()) {
-                       base = kmalloc_node(table_size, GFP_KERNEL, nid);
+                       base = kmalloc_node(table_size,
+                                       GFP_KERNEL | __GFP_NOWARN, nid);
                        if (!base)
                                base = vmalloc_node(table_size, nid);
                } else {
@@ -284,12 +285,8 @@ struct swap_cgroup_ctrl {
 
 struct swap_cgroup_ctrl swap_cgroup_ctrl[MAX_SWAPFILES];
 
-/*
- * This 8bytes seems big..maybe we can reduce this when we can use "id" for
- * cgroup rather than pointer.
- */
 struct swap_cgroup {
-       struct mem_cgroup       *val;
+       unsigned short          id;
 };
 #define SC_PER_PAGE    (PAGE_SIZE/sizeof(struct swap_cgroup))
 #define SC_POS_MASK    (SC_PER_PAGE - 1)
@@ -341,10 +338,10 @@ not_enough_page:
  * @ent: swap entry to be recorded into
  * @mem: mem_cgroup to be recorded
  *
- * Returns old value at success, NULL at failure.
- * (Of course, old value can be NULL.)
+ * Returns old value at success, 0 at failure.
+ * (Of course, old value can be 0.)
  */
-struct mem_cgroup *swap_cgroup_record(swp_entry_t ent, struct mem_cgroup *mem)
+unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id)
 {
        int type = swp_type(ent);
        unsigned long offset = swp_offset(ent);
@@ -353,18 +350,18 @@ struct mem_cgroup *swap_cgroup_record(swp_entry_t ent, struct mem_cgroup *mem)
        struct swap_cgroup_ctrl *ctrl;
        struct page *mappage;
        struct swap_cgroup *sc;
-       struct mem_cgroup *old;
+       unsigned short old;
 
        if (!do_swap_account)
-               return NULL;
+               return 0;
 
        ctrl = &swap_cgroup_ctrl[type];
 
        mappage = ctrl->map[idx];
        sc = page_address(mappage);
        sc += pos;
-       old = sc->val;
-       sc->val = mem;
+       old = sc->id;
+       sc->id = id;
 
        return old;
 }
@@ -373,9 +370,9 @@ struct mem_cgroup *swap_cgroup_record(swp_entry_t ent, struct mem_cgroup *mem)
  * lookup_swap_cgroup - lookup mem_cgroup tied to swap entry
  * @ent: swap entry to be looked up.
  *
- * Returns pointer to mem_cgroup at success. NULL at failure.
+ * Returns CSS ID of mem_cgroup at success. 0 at failure. (0 is invalid ID)
  */
-struct mem_cgroup *lookup_swap_cgroup(swp_entry_t ent)
+unsigned short lookup_swap_cgroup(swp_entry_t ent)
 {
        int type = swp_type(ent);
        unsigned long offset = swp_offset(ent);
@@ -384,16 +381,16 @@ struct mem_cgroup *lookup_swap_cgroup(swp_entry_t ent)
        struct swap_cgroup_ctrl *ctrl;
        struct page *mappage;
        struct swap_cgroup *sc;
-       struct mem_cgroup *ret;
+       unsigned short ret;
 
        if (!do_swap_account)
-               return NULL;
+               return 0;
 
        ctrl = &swap_cgroup_ctrl[type];
        mappage = ctrl->map[idx];
        sc = page_address(mappage);
        sc += pos;
-       ret = sc->val;
+       ret = sc->id;
        return ret;
 }
 
@@ -429,13 +426,6 @@ int swap_cgroup_swapon(int type, unsigned long max_pages)
        }
        mutex_unlock(&swap_cgroup_mutex);
 
-       printk(KERN_INFO
-               "swap_cgroup: uses %ld bytes of vmalloc for pointer array space"
-               " and %ld bytes to hold mem_cgroup pointers on swap\n",
-               array_size, length * PAGE_SIZE);
-       printk(KERN_INFO
-       "swap_cgroup can be disabled by noswapaccount boot option.\n");
-
        return 0;
 nomem:
        printk(KERN_INFO "couldn't allocate enough memory for swap_cgroup.\n");