lkml.org 
[lkml]   [2023]   [Oct]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] mm: memcontrol: Don't css_get() on root_mem_cgroup in get_mem_cgroup_from_mm()
Date
As reference counting in the root memcg is disabled, there is no need
to get a reference if root memcg is to be returned.

Signed-off-by: Waiman Long <longman@redhat.com>
---
mm/memcontrol.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 5b009b233ab8..2b3864194042 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1060,8 +1060,10 @@ struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm)
rcu_read_lock();
do {
memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
- if (unlikely(!memcg))
+ if (unlikely(!memcg)) {
memcg = root_mem_cgroup;
+ break;
+ }
} while (!css_tryget(&memcg->css));
rcu_read_unlock();
return memcg;
--
2.39.3
\
 
 \ /
  Last update: 2023-10-12 18:16    [W:0.038 / U:0.692 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site