diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 8ab1d42664f..3878cfe399d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2236,7 +2236,12 @@ static int mem_cgroup_move_account(struct page_cgroup *pc, { int ret = -EINVAL; unsigned long flags; - + /* + * The page is isolated from LRU. So, collapse function + * will not handle this page. But page splitting can happen. + * Do this check under compound_page_lock(). The caller should + * hold it. + */ if ((charge_size > PAGE_SIZE) && !PageTransHuge(pc->page)) return -EBUSY; @@ -2268,7 +2273,7 @@ static int mem_cgroup_move_parent(struct page_cgroup *pc, struct cgroup *cg = child->css.cgroup; struct cgroup *pcg = cg->parent; struct mem_cgroup *parent; - int charge = PAGE_SIZE; + int page_size = PAGE_SIZE; unsigned long flags; int ret; @@ -2281,22 +2286,24 @@ static int mem_cgroup_move_parent(struct page_cgroup *pc, goto out; if (isolate_lru_page(page)) goto put; - /* The page is isolated from LRU and we have no race with splitting */ - charge = PAGE_SIZE << compound_order(page); + + if (PageTransHuge(page)) + page_size = HPAGE_SIZE; parent = mem_cgroup_from_cont(pcg); - ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false, charge); + ret = __mem_cgroup_try_charge(NULL, gfp_mask, + &parent, false, page_size); if (ret || !parent) goto put_back; - if (charge > PAGE_SIZE) + if (page_size > PAGE_SIZE) flags = compound_lock_irqsave(page); - ret = mem_cgroup_move_account(pc, child, parent, true, charge); + ret = mem_cgroup_move_account(pc, child, parent, true, page_size); if (ret) - mem_cgroup_cancel_charge(parent, charge); + mem_cgroup_cancel_charge(parent, page_size); - if (charge > PAGE_SIZE) + if (page_size > PAGE_SIZE) compound_unlock_irqrestore(page, flags); put_back: putback_lru_page(page);