Jan Kara 5d5a802ec2 fs/drop_caches.c: avoid softlockups in drop_pagecache_sb()
[ Upstream commit c27d82f52f75fc9d8d9d40d120d2a96fdeeada5e ]

When superblock has lots of inodes without any pagecache (like is the
case for /proc), drop_pagecache_sb() will iterate through all of them
without dropping sb->s_inode_list_lock which can lead to softlockups
(one of our customers hit this).

Fix the problem by going to the slow path and doing cond_resched() in
case the process needs rescheduling.

Link: http://lkml.kernel.org/r/20190114085343.15011-1-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-23 08:44:26 +01:00
..
2017-12-20 10:04:56 +01:00
2018-12-13 09:21:27 +01:00
2018-12-17 21:55:12 +01:00
2017-11-30 08:37:20 +00:00
2019-03-23 08:44:21 +01:00
2018-09-15 09:40:41 +02:00
2019-02-20 10:13:09 +01:00
2018-12-21 14:09:50 +01:00
2015-11-10 12:07:22 -08:00
2017-06-14 13:16:24 +02:00
2015-11-16 23:54:45 -08:00
2018-05-16 10:06:51 +02:00
2015-11-16 23:54:45 -08:00
2017-06-14 13:16:24 +02:00
2018-02-16 20:09:43 +01:00
2017-06-14 13:16:24 +02:00
2018-09-09 20:04:36 +02:00