[folded-merged] mm-readahead-dont-decrease-mmap_miss-when-folio-has-workingset-flags-fix.patch removed from -mm tree

[folded-merged] mm-readahead-dont-decrease-mmap_miss-when-folio-has-workingset-flags-fix.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: mm/filemap: don't decrease mmap_miss when folio has workingset flag
has been removed from the -mm tree.  Its filename was
     mm-readahead-dont-decrease-mmap_miss-when-folio-has-workingset-flags-fix.patch

This patch was dropped because it was folded into mm-readahead-dont-decrease-mmap_miss-when-folio-has-workingset-flags.patch

------------------------------------------------------
From: Liu Shixin <liushixin2@huawei.com>
Subject: mm/filemap: don't decrease mmap_miss when folio has workingset flag
Date: Tue, 26 Mar 2024 14:50:26 +0800

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Link: https://lkml.kernel.org/r/20240326065026.1910584-1-liushixin2@huawei.com
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jinjiang Tu <tujinjiang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/filemap.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/mm/filemap.c~mm-readahead-dont-decrease-mmap_miss-when-folio-has-workingset-flags-fix
+++ a/mm/filemap.c
@@ -3492,6 +3492,13 @@ static vm_fault_t filemap_map_folio_rang
 		if (PageHWPoison(page + count))
 			goto skip;
 
+		/*
+		 * If there are too many folios that are recently evicted
+		 * in a file, they will probably continue to be evicted.
+		 * In such situation, read-ahead is only a waste of IO.
+		 * Don't decrease mmap_miss in this scenario to make sure
+		 * we can stop read-ahead.
+		 */
 		if (!folio_test_workingset(folio))
 			(*mmap_miss)++;
 
@@ -3542,6 +3549,7 @@ static vm_fault_t filemap_map_order0_fol
 	if (PageHWPoison(page))
 		return ret;
 
+	/* See comment of filemap_map_folio_range() */
 	if (!folio_test_workingset(folio))
 		(*mmap_miss)++;
 
_

Patches currently in -mm which might be from liushixin2@huawei.com are

mm-readahead-break-read-ahead-loop-if-filemap_add_folio-return-enomem.patch
mm-readahead-dont-decrease-mmap_miss-when-folio-has-workingset-flags.patch