2020-10-29 10:47:30

by Alex Shi

Subject: [PATCH v20 09/20] mm/memcg: add debug checking in lock_page_memcg

Add a debug checking in lock_page_memcg, then we could get alarm
if anything wrong here.

Suggested-by: Johannes Weiner <[email protected]>
Signed-off-by: Alex Shi <[email protected]>
Acked-by: Hugh Dickins <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Vladimir Davydov <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
---
mm/memcontrol.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index e46b9f9501c2..599aa8863111 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2142,6 +2142,12 @@ struct mem_cgroup *lock_page_memcg(struct page *page)
if (unlikely(!memcg))
return NULL;

+#ifdef CONFIG_PROVE_LOCKING
+ local_irq_save(flags);
+ might_lock(&memcg->move_lock);
+ local_irq_restore(flags);
+#endif
+
if (atomic_read(&memcg->moving_account) <= 0)
return memcg;

--
1.8.3.1

2020-11-02 14:49:30

by Johannes Weiner

Subject: Re: [PATCH v20 09/20] mm/memcg: add debug checking in lock_page_memcg

On Thu, Oct 29, 2020 at 06:44:54PM +0800, Alex Shi wrote:
> Add a debug checking in lock_page_memcg, then we could get alarm
> if anything wrong here.
>
> Suggested-by: Johannes Weiner <[email protected]>
> Signed-off-by: Alex Shi <[email protected]>
> Acked-by: Hugh Dickins <[email protected]>
> Cc: Johannes Weiner <[email protected]>
> Cc: Michal Hocko <[email protected]>
> Cc: Vladimir Davydov <[email protected]>
> Cc: Andrew Morton <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]

Acked-by: Johannes Weiner <[email protected]>