memcg: lru_size instead of MEM_CGROUP_ZSTAT

I never understood why we need a MEM_CGROUP_ZSTAT(mz, idx) macro to
obscure the LRU counts.  For easier searching? So call it lru_size
rather than bare count (lru_length sounds better, but would be wrong,
since each huge page raises lru_size hugely).

Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 8 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index e5370db7ad72..6405e78e26e7 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -135,7 +135,7 @@ struct mem_cgroup_reclaim_iter {
  */
 struct mem_cgroup_per_zone {
         struct lruvec           lruvec;
-        unsigned long           count[NR_LRU_LISTS];
+        unsigned long           lru_size[NR_LRU_LISTS];
 
         struct mem_cgroup_reclaim_iter reclaim_iter[DEF_PRIORITY + 1];
 
@@ -147,8 +147,6 @@ struct mem_cgroup_per_zone {
         struct mem_cgroup       *memcg;         /* Back pointer, we cannot */
                                                 /* use container_of        */
 };
-/* Macro for accessing counter */
-#define MEM_CGROUP_ZSTAT(mz, idx)       ((mz)->count[(idx)])
 
 struct mem_cgroup_per_node {
         struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES];
@@ -728,7 +726,7 @@ mem_cgroup_zone_nr_lru_pages(struct mem_cgroup *memcg, int nid, int zid,
 
         for_each_lru(l) {
                 if (BIT(l) & lru_mask)
-                        ret += MEM_CGROUP_ZSTAT(mz, l);
+                        ret += mz->lru_size[l];
         }
         return ret;
 }
@@ -1077,7 +1075,7 @@ struct lruvec *mem_cgroup_lru_add_list(struct zone *zone, struct page *page,
 
         mz = page_cgroup_zoneinfo(memcg, page);
         /* compound_order() is stabilized through lru_lock */
-        MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page);
+        mz->lru_size[lru] += 1 << compound_order(page);
         return &mz->lruvec;
 }
 
@@ -1105,8 +1103,8 @@ void mem_cgroup_lru_del_list(struct page *page, enum lru_list lru)
         VM_BUG_ON(!memcg);
         mz = page_cgroup_zoneinfo(memcg, page);
         /* huge page split is done under lru_lock. so, we have no races. */
-        VM_BUG_ON(MEM_CGROUP_ZSTAT(mz, lru) < (1 << compound_order(page)));
-        MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page);
+        VM_BUG_ON(mz->lru_size[lru] < (1 << compound_order(page)));
+        mz->lru_size[lru] -= 1 << compound_order(page);
 }
 
 void mem_cgroup_lru_del(struct page *page)
@@ -3629,7 +3627,7 @@ static int mem_cgroup_force_empty_list(struct mem_cgroup *memcg,
         mz = mem_cgroup_zoneinfo(memcg, node, zid);
         list = &mz->lruvec.lists[lru];
 
-        loop = MEM_CGROUP_ZSTAT(mz, lru);
+        loop = mz->lru_size[lru];
         /* give some margin against EBUSY etc...*/
         loop += 256;
         busy = NULL;