diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index e32ab948f589..d4575a1d6e99 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -68,10 +68,9 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage, struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *); struct lruvec *mem_cgroup_page_lruvec(struct page *, struct zone *); -bool __mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg, - struct mem_cgroup *memcg); -bool task_in_mem_cgroup(struct task_struct *task, - const struct mem_cgroup *memcg); +bool mem_cgroup_is_descendant(struct mem_cgroup *memcg, + struct mem_cgroup *root); +bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg); extern struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page); extern struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p); @@ -79,8 +78,8 @@ extern struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p); extern struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg); extern struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css); -static inline -bool mm_match_cgroup(const struct mm_struct *mm, const struct mem_cgroup *memcg) +static inline bool mm_match_cgroup(struct mm_struct *mm, + struct mem_cgroup *memcg) { struct mem_cgroup *task_memcg; bool match = false; @@ -88,7 +87,7 @@ bool mm_match_cgroup(const struct mm_struct *mm, const struct mem_cgroup *memcg) rcu_read_lock(); task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); if (task_memcg) - match = __mem_cgroup_same_or_subtree(memcg, task_memcg); + match = mem_cgroup_is_descendant(task_memcg, memcg); rcu_read_unlock(); return match; } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index e5dcebd71dfb..b841bf430179 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1328,41 +1328,24 @@ void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, VM_BUG_ON((long)(*lru_size) < 0); } -/* - * Checks whether given mem is same or in the root_mem_cgroup's - * hierarchy subtree - */ -bool __mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg, - struct mem_cgroup *memcg) +bool mem_cgroup_is_descendant(struct mem_cgroup *memcg, struct mem_cgroup *root) { - if (root_memcg == memcg) + if (root == memcg) return true; - if (!root_memcg->use_hierarchy) + if (!root->use_hierarchy) return false; - return cgroup_is_descendant(memcg->css.cgroup, root_memcg->css.cgroup); + return cgroup_is_descendant(memcg->css.cgroup, root->css.cgroup); } -static bool mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg, - struct mem_cgroup *memcg) +bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg) { - bool ret; - - rcu_read_lock(); - ret = __mem_cgroup_same_or_subtree(root_memcg, memcg); - rcu_read_unlock(); - return ret; -} - -bool task_in_mem_cgroup(struct task_struct *task, - const struct mem_cgroup *memcg) -{ - struct mem_cgroup *curr; + struct mem_cgroup *task_memcg; struct task_struct *p; bool ret; p = find_lock_task_mm(task); if (p) { - curr = get_mem_cgroup_from_mm(p->mm); + task_memcg = get_mem_cgroup_from_mm(p->mm); task_unlock(p); } else { /* @@ -1371,18 +1354,12 @@ bool task_in_mem_cgroup(struct task_struct *task, * killed to prevent needlessly killing additional tasks. */ rcu_read_lock(); - curr = mem_cgroup_from_task(task); - css_get(&curr->css); + task_memcg = mem_cgroup_from_task(task); + css_get(&task_memcg->css); rcu_read_unlock(); } - /* - * We should check use_hierarchy of "memcg" not "curr". Because checking - * use_hierarchy of "curr" here make this function true if hierarchy is - * enabled in "curr" and "curr" is a child of "memcg" in *cgroup* - * hierarchy(even if use_hierarchy is disabled in "memcg"). - */ - ret = mem_cgroup_same_or_subtree(memcg, curr); - css_put(&curr->css); + ret = mem_cgroup_is_descendant(task_memcg, memcg); + css_put(&task_memcg->css); return ret; } @@ -1467,8 +1444,8 @@ static bool mem_cgroup_under_move(struct mem_cgroup *memcg) if (!from) goto unlock; - ret = mem_cgroup_same_or_subtree(memcg, from) - || mem_cgroup_same_or_subtree(memcg, to); + ret = mem_cgroup_is_descendant(from, memcg) || + mem_cgroup_is_descendant(to, memcg); unlock: spin_unlock(&mc.lock); return ret; @@ -1900,12 +1877,8 @@ static int memcg_oom_wake_function(wait_queue_t *wait, oom_wait_info = container_of(wait, struct oom_wait_info, wait); oom_wait_memcg = oom_wait_info->memcg; - /* - * Both of oom_wait_info->memcg and wake_memcg are stable under us. - * Then we can use css_is_ancestor without taking care of RCU. - */ - if (!mem_cgroup_same_or_subtree(oom_wait_memcg, wake_memcg) - && !mem_cgroup_same_or_subtree(wake_memcg, oom_wait_memcg)) + if (!mem_cgroup_is_descendant(wake_memcg, oom_wait_memcg) && + !mem_cgroup_is_descendant(oom_wait_memcg, wake_memcg)) return 0; return autoremove_wake_function(wait, mode, sync, arg); } @@ -2225,7 +2198,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg) memcg = stock->cached; if (!memcg || !stock->nr_pages) continue; - if (!mem_cgroup_same_or_subtree(root_memcg, memcg)) + if (!mem_cgroup_is_descendant(memcg, root_memcg)) continue; if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { if (cpu == curcpu) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 5340f6b91312..3b014d326151 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -119,7 +119,7 @@ found: /* return true if the task is not adequate as candidate victim task. */ static bool oom_unkillable_task(struct task_struct *p, - const struct mem_cgroup *memcg, const nodemask_t *nodemask) + struct mem_cgroup *memcg, const nodemask_t *nodemask) { if (is_global_init(p)) return true; @@ -353,7 +353,7 @@ static struct task_struct *select_bad_process(unsigned int *ppoints, * State information includes task's pid, uid, tgid, vm size, rss, nr_ptes, * swapents, oom_score_adj value, and name. */ -static void dump_tasks(const struct mem_cgroup *memcg, const nodemask_t *nodemask) +static void dump_tasks(struct mem_cgroup *memcg, const nodemask_t *nodemask) { struct task_struct *p; struct task_struct *task;