From: Tahsin Erdogan <tahsin@google.com>
Date: Tue, 16 Feb 2016 21:34:39 +0000 (-0800)
Subject: writeback: initialize inode members that track writeback history
X-Git-Tag: firefly_0821_release~176^2~4^2~11^2~3
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=1f565de67d6f2991f10ab591d819135ba4d3fe0f;p=firefly-linux-kernel-4.4.55.git

writeback: initialize inode members that track writeback history

inode struct members that track cgroup writeback information
should be reinitialized when inode gets allocated from
kmem_cache. Otherwise, their values remain and get used by the
new inode.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Fixes: d10c80955265 ("writeback: implement foreign cgroup inode bdi_writeback switching")
Signed-off-by: Jens Axboe <axboe@fb.com>
(cherry picked from commit 3d65ae4634ed8350aee98a4e6f4e41fe40c7d282)
Signed-off-by: Alex Shi <alex.shi@linaro.org>
---

diff --git a/fs/inode.c b/fs/inode.c
index b0edef500590..2c16b758831d 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -154,6 +154,12 @@ int inode_init_always(struct super_block *sb, struct inode *inode)
 	inode->i_rdev = 0;
 	inode->dirtied_when = 0;
 
+#ifdef CONFIG_CGROUP_WRITEBACK
+	inode->i_wb_frn_winner = 0;
+	inode->i_wb_frn_avg_time = 0;
+	inode->i_wb_frn_history = 0;
+#endif
+
 	if (security_inode_alloc(inode))
 		goto out;
 	spin_lock_init(&inode->i_lock);