The swap charges the actual number of swap entries on cgroup v2.
If a swap cache page is charged successful, and then we uncharge
the swap counter. It is wrong on cgroup v2. Because the swap
entry is not freed.
Fixes: 2d1c498072de ("mm: memcontrol: make swap tracking an integral part of memory control")
Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
mm/memcontrol.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c737c8f05992..be6bc5044150 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -6753,7 +6753,7 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
memcg_check_events(memcg, page);
local_irq_enable();
- if (PageSwapCache(page)) {
+ if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && PageSwapCache(page)) {
swp_entry_t entry = { .val = page_private(page) };
/*
* The swap entry might not get freed for a long time,
--
2.11.0
