None of the mem_cgroup_same_or_subtree() callers actually require it to
take the RCU lock, either because they hold it themselves or they have css
references. Remove it.
To make the API change clear, rename the leftover helper to
mem_cgroup_is_descendant() to match cgroup_is_descendant().
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *);
struct lruvec *mem_cgroup_page_lruvec(struct page *, struct zone *);
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);
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);
extern struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg);
extern struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css);
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;
{
struct mem_cgroup *task_memcg;
bool match = false;
rcu_read_lock();
task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
if (task_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;
}
rcu_read_unlock();
return match;
}
VM_BUG_ON((long)(*lru_size) < 0);
}
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->use_hierarchy)
+ if (!root->use_hierarchy)
- return cgroup_is_descendant(memcg->css.cgroup, root_memcg->css.cgroup);
-}
-
-static bool mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg,
- struct mem_cgroup *memcg)
-{
- bool ret;
-
- rcu_read_lock();
- ret = __mem_cgroup_same_or_subtree(root_memcg, memcg);
- rcu_read_unlock();
- return ret;
+ return cgroup_is_descendant(memcg->css.cgroup, root->css.cgroup);
-bool task_in_mem_cgroup(struct task_struct *task,
- const struct mem_cgroup *memcg)
+bool task_in_mem_cgroup(struct task_struct *task, 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) {
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 {
/*
task_unlock(p);
} else {
/*
* killed to prevent needlessly killing additional tasks.
*/
rcu_read_lock();
* 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);
- /*
- * 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);
- 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;
unlock:
spin_unlock(&mc.lock);
return ret;
oom_wait_info = container_of(wait, struct oom_wait_info, wait);
oom_wait_memcg = oom_wait_info->memcg;
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);
}
return 0;
return autoremove_wake_function(wait, mode, sync, arg);
}
memcg = stock->cached;
if (!memcg || !stock->nr_pages)
continue;
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)
continue;
if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) {
if (cpu == curcpu)
/* return true if the task is not adequate as candidate victim task. */
static bool oom_unkillable_task(struct task_struct *p,
/* 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;
{
if (is_global_init(p))
return true;
* State information includes task's pid, uid, tgid, vm size, rss, nr_ptes,
* swapents, oom_score_adj value, and name.
*/
* 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;
{
struct task_struct *p;
struct task_struct *task;