[PATCH 1/2] mm: vmscan: filter out the dirty file folios for node_reclaim()

[Baolin Wang]

After commit 6b0dfabb3555 ("fs: Remove aops->writepage"), we no longer
attempt to write back filesystem folios in pageout(), and only tmpfs/shmem
folios and anonymous swapcache folios can be written back. Therefore,
we should also filter out the dirty filesystem folios for node_reclaim()
to avoid unnecessary LRU scans.

Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
---
 mm/vmscan.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index aadbee50a851..f347865edc70 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -7601,9 +7601,11 @@ static unsigned long node_pagecache_reclaimable(struct pglist_data *pgdat)
 	else
 		nr_pagecache_reclaimable = node_unmapped_file_pages(pgdat);
 
-	/* If we can't clean pages, remove dirty pages from consideration */
-	if (!(node_reclaim_mode & RECLAIM_WRITE))
-		delta += node_page_state(pgdat, NR_FILE_DIRTY);
+	/*
+	 * Since we can't clean folios through reclaim, remove dirty file
+	 * folios from consideration.
+	 */
+	delta += node_page_state(pgdat, NR_FILE_DIRTY);
 
 	/* Watch for any possible underflows due to delta */
 	if (unlikely(delta > nr_pagecache_reclaimable))
-- 
2.43.7