[PATCH v4 09/17] mm/damon: convert to LRU refs based operations for MGLRU

[Kairui Song via B4 Relay]

From: Kairui Song <kasong@xxxxxxxxxxx>

damon_pa_pageout() cleared PG_referenced directly, which under MGLRU
may corrupts the folio's refs count in later commits. That flag is now
bit 0 of the count (LRU_REFS_FLAGS).

Reset the count instead under MGLRU.

Tested-by: zhaozhengzhuo <zhaozhengzhuo@xxxxxxxxxxxxx>
Signed-off-by: Kairui Song <kasong@xxxxxxxxxxx>
---
 mm/damon/paddr.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index 2cfdc356b415..6412ff2396b3 100644
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -279,7 +279,8 @@ static unsigned long damon_pa_pageout(struct damon_region *r,
 		else
 			*sz_filter_passed += folio_size(folio) / addr_unit;
 
-		folio_clear_referenced(folio);
+		/* The regions is cold, better drop the hotness info */
+		folio_clear_lru_refs(folio);
 		folio_test_clear_young(folio);
 		if (!folio_isolate_lru(folio))
 			goto put_folio;

-- 
2.56.0