[PATCH 4.20 70/92] Revert "mm: dont reclaim inodes with many attached pages"

[Greg Kroah-Hartman]

4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dave Chinner <dchinner@xxxxxxxxxx>

commit 69056ee6a8a3d576ed31e38b3b14c70d6c74edcc upstream.

This reverts commit a76cf1a474d7d ("mm: don't reclaim inodes with many
attached pages").

This change causes serious changes to page cache and inode cache
behaviour and balance, resulting in major performance regressions when
combining worklaods such as large file copies and kernel compiles.

  https://bugzilla.kernel.org/show_bug.cgi?id=202441

This change is a hack to work around the problems introduced by changing
how agressive shrinkers are on small caches in commit 172b06c32b94 ("mm:
slowly shrink slabs with a relatively small number of objects").  It
creates more problems than it solves, wasn't adequately reviewed or
tested, so it needs to be reverted.

Link: http://lkml.kernel.org/r/20190130041707.27750-2-david@xxxxxxxxxxxxx
Fixes: a76cf1a474d7d ("mm: don't reclaim inodes with many attached pages")
Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
Cc: Wolfgang Walter <linux@xxxxxxx>
Cc: Roman Gushchin <guro@xxxxxx>
Cc: Spock <dairinin@xxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 fs/inode.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

--- a/fs/inode.c
+++ b/fs/inode.c
@@ -730,11 +730,8 @@ static enum lru_status inode_lru_isolate
 		return LRU_REMOVED;
 	}
 
-	/*
-	 * Recently referenced inodes and inodes with many attached pages
-	 * get one more pass.
-	 */
-	if (inode->i_state & I_REFERENCED || inode->i_data.nrpages > 1) {
+	/* recently referenced inodes get one more pass */
+	if (inode->i_state & I_REFERENCED) {
 		inode->i_state &= ~I_REFERENCED;
 		spin_unlock(&inode->i_lock);
 		return LRU_ROTATE;