[08/19] mm/memcg: add debug checking in lock_page_memcg

Commit Message

Andrew Morton Dec. 15, 2020, 8:33 p.m. UTC

From: Alex Shi <[e-mail]>
Subject: 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.

Link: https://lkml.kernel.org/r/[e-mail]
Suggested-by: Johannes Weiner <[e-mail]>
Signed-off-by: Alex Shi <[e-mail]>
Acked-by: Hugh Dickins <[e-mail]>
Acked-by: Johannes Weiner <[e-mail]>
Cc: Michal Hocko <[e-mail]>
Cc: Vladimir Davydov <[e-mail]>
Cc: Alexander Duyck <[e-mail]>
Cc: Andrea Arcangeli <[e-mail]>
Cc: Andrey Ryabinin <[e-mail]>
Cc: "Chen, Rong A" <[e-mail]>
Cc: Daniel Jordan <[e-mail]>
Cc: "Huang, Ying" <[e-mail]>
Cc: Jann Horn <[e-mail]>
Cc: Joonsoo Kim <[e-mail]>
Cc: Kirill A. Shutemov <[e-mail]>
Cc: Kirill A. Shutemov <[e-mail]>
Cc: Konstantin Khlebnikov <[e-mail]>
Cc: Matthew Wilcox (Oracle) <[e-mail]>
Cc: Mel Gorman <[e-mail]>
Cc: Michal Hocko <[e-mail]>
Cc: Mika Penttilä <[e-mail]>
Cc: Minchan Kim <[e-mail]>
Cc: Shakeel Butt <[e-mail]>
Cc: Tejun Heo <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Vlastimil Babka <[e-mail]>
Cc: Wei Yang <[e-mail]>
Cc: Yang Shi <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 mm/memcontrol.c |    6 ++++++
 1 file changed, 6 insertions(+)

Patch

--- a/mm/memcontrol.c~mm-memcg-add-debug-checking-in-lock_page_memcg
+++ a/mm/memcontrol.c
@@ -2150,6 +2150,12 @@  again:
 	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;