From: "andrew.yang" <andrew.yang@xxxxxxxxxxxx>
damon_get_folio() would always increase folio _refcount and
folio_isolate_lru() would increase folio _refcount if the folio's lru
flag is set.
If an unevictable folio isolated successfully, there will be two more
_refcount. The one from folio_isolate_lru() will be decreased in
folio_puback_lru(), but the other one from damon_get_folio() will be
left behind. This causes a pin page.
Whatever the case, the _refcount from damon_get_folio() should be
decreased.
Signed-off-by: andrew.yang <andrew.yang@xxxxxxxxxxxx>
---
v2:
according to David's suggestion
1. revise subject
according to SeongJae's suggestions
1. rebase to mm-unstable tree
2. remove braces for th single statements
---
mm/damon/paddr.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index 607bb69e526c..6c655d9b5639 100644
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -250,12 +250,11 @@ static unsigned long damon_pa_pageout(struct damon_region *r, struct damos *s)
folio_put(folio);
continue;
}
- if (folio_test_unevictable(folio)) {
+ if (folio_test_unevictable(folio))
folio_putback_lru(folio);
- } else {
+ else
list_add(&folio->lru, &folio_list);
- folio_put(folio);
- }
+ folio_put(folio);
}
applied = reclaim_pages(&folio_list);
cond_resched();
--
2.18.0
