If folios were freed from under us, there's no need to reclaim them. Skip
these folios to save lots of cpu cycles and avoid possible unnecessary
disk IO.
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
mm/vmscan.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/mm/vmscan.c b/mm/vmscan.c
index f7d9a683e3a7..646dd1efad32 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1556,12 +1556,18 @@ static unsigned int shrink_page_list(struct list_head *page_list,
folio = lru_to_folio(page_list);
list_del(&folio->lru);
+ nr_pages = folio_nr_pages(folio);
+ if (folio_ref_count(folio) == 1) {
+ /* folio was freed from under us. So we are done. */
+ WARN_ON(!folio_put_testzero(folio));
+ goto free_it;
+ }
+
if (!folio_trylock(folio))
goto keep;
VM_BUG_ON_FOLIO(folio_test_active(folio), folio);
- nr_pages = folio_nr_pages(folio);
/* Account the number of base pages */
sc->nr_scanned += nr_pages;
--
2.23.0
