1 files changed, 2 insertions, 10 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 750ed144995..ad7f36f676f 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1031,8 +1031,6 @@ void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru)
         mz = page_cgroup_zoneinfo(pc->mem_cgroup, page);
         /* huge page split is done under lru_lock. so, we have no races. */
         MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page);
-        if (mem_cgroup_is_root(pc->mem_cgroup))
-                return;
         VM_BUG_ON(list_empty(&pc->lru));
         list_del_init(&pc->lru);
 }
@@ -1057,13 +1055,11 @@ void mem_cgroup_rotate_reclaimable_page(struct page *page)
                 return;
 
         pc = lookup_page_cgroup(page);
-        /* unused or root page is not rotated. */
+        /* unused page is not rotated. */
         if (!PageCgroupUsed(pc))
                 return;
         /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */
         smp_rmb();
-        if (mem_cgroup_is_root(pc->mem_cgroup))
-                return;
         mz = page_cgroup_zoneinfo(pc->mem_cgroup, page);
         list_move_tail(&pc->lru, &mz->lists[lru]);
 }
@@ -1077,13 +1073,11 @@ void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru)
                 return;
 
         pc = lookup_page_cgroup(page);
-        /* unused or root page is not rotated. */
+        /* unused page is not rotated. */
         if (!PageCgroupUsed(pc))
                 return;
         /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */
         smp_rmb();
-        if (mem_cgroup_is_root(pc->mem_cgroup))
-                return;
         mz = page_cgroup_zoneinfo(pc->mem_cgroup, page);
         list_move(&pc->lru, &mz->lists[lru]);
 }
@@ -1115,8 +1109,6 @@ void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru)
         /* huge page split is done under lru_lock. so, we have no races. */
         MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page);
         SetPageCgroupAcctLRU(pc);
-        if (mem_cgroup_is_root(pc->mem_cgroup))
-                return;
         list_add(&pc->lru, &mz->lists[lru]);
 }