From f168a9a54ec39b3f832c353733898b713b6b5c1f Mon Sep 17 00:00:00 2001
From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Date: Thu, 11 Jul 2019 21:00:20 -0700
Subject: [PATCH] mm: memcontrol: use CSS_TASK_ITER_PROCS at
mem_cgroup_scan_tasks()
Since commit c03cd7738a83 ("cgroup: Include dying leaders with live
threads in PROCS iterations") corrected how CSS_TASK_ITER_PROCS works,
mem_cgroup_scan_tasks() can use CSS_TASK_ITER_PROCS in order to check
only one thread from each thread group.
[penguin-kernel@I-love.SAKURA.ne.jp: remove thread group leader check in oom_evaluate_task()]
Link: http://lkml.kernel.org/r/1560853257-14934-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp
Link: http://lkml.kernel.org/r/c763afc8-f0ae-756a-56a7-395f625b95fc@i-love.sakura.ne.jp
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
mm/memcontrol.c | 2 +-
mm/oom_kill.c | 3 ---
2 files changed, 1 insertion(+), 4 deletions(-)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 2cb7e4e5c51a..773ae5674e12 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1167,7 +1167,7 @@ int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
struct css_task_iter it;
struct task_struct *task;
- css_task_iter_start(&iter->css, 0, &it);
+ css_task_iter_start(&iter->css, CSS_TASK_ITER_PROCS, &it);
while (!ret && (task = css_task_iter_next(&it)))
ret = fn(task, arg);
css_task_iter_end(&it);
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index f719b64741d6..606e5e4c6a3e 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -346,9 +346,6 @@ static int oom_evaluate_task(struct task_struct *task, void *arg)
if (!points || points < oc->chosen_points)
goto next;
- /* Prefer thread group leaders for display purposes */
- if (points == oc->chosen_points && thread_group_leader(oc->chosen))
- goto next;
select:
if (oc->chosen)
put_task_struct(oc->chosen);