linux-kernel - [PATCH] mm/memcontrol: Skip root memcg in memcg_memory_event

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20221215091907.763801-1-haifeng.xu@shopee.com>
Date:   Thu, 15 Dec 2022 09:19:07 +0000
From:   Haifeng Xu <haifeng.xu@...pee.com>
To:     akpm@...ux-foundation.org
Cc:     shakeelb@...gle.com, roman.gushchin@...ux.dev,
        songmuchun@...edance.com, hannes@...xchg.org, vbabka@...e.cz,
        willy@...radead.org, vasily.averin@...ux.dev,
        linux-kernel@...r.kernel.org, Haifeng Xu <haifeng.xu@...pee.com>
Subject: [PATCH] mm/memcontrol: Skip root memcg in memcg_memory_event_mm

The memory events aren't supported on root cgroup, so there is no need
to account MEMCG_OOM_KILL on root memcg.

Signed-off-by: Haifeng Xu <haifeng.xu@...pee.com>
---
 include/linux/memcontrol.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 567f12323f55..09f75161a3bc 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1142,7 +1142,7 @@ static inline void memcg_memory_event_mm(struct mm_struct *mm,
 
 	rcu_read_lock();
 	memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
-	if (likely(memcg))
+	if (likely(memcg && !mem_cgroup_is_root(memcg)))
 		memcg_memory_event(memcg, event);
 	rcu_read_unlock();
 }
-- 
2.25.1