mm: vmscan: filter out the dirty file folios for node_reclaim()

Patch series "optimize the logic for handling dirty file folios during
reclaim", v2.

Since we no longer attempt to write back filesystem folios during reclaim,
some logic for handling dirty file folios in the reclaim process also
needs to be updated.  Please check the details in each patch.

This patch (of 2):

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.

Link: https://lkml.kernel.org/r/cover.1760687075.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/c91f5ecc5152b647904c7503618a01885d913928.1760687075.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/vmscan.c b/mm/vmscan.c
index aab85ef70c1c7ffa4866cb9c3f8d9937f70a8538..320831e78b92fd520329510879a50d3a0d16eea2 100644 (file)
--- 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))