From e38cf302b2e92a870f23e07c4390e04685779340 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@redhat.com>
Date: Mon, 11 Dec 2017 06:35:22 -0500
Subject: [PATCH 19/24] fs: only set S_VERSION when updating times if necessary
Git-commit: e38cf302b2e92a870f23e07c4390e04685779340
Patch-mainline: v4.16-rc1
References: bsc#1081186
We only really need to update i_version if someone has queried for it
since we last incremented it. By doing that, we can avoid having to
update the inode if the times haven't changed.
If the times have changed, then we go ahead and forcibly increment the
counter, under the assumption that we'll be going to the storage
anyway, and the increment itself is relatively cheap.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Jan Kara <jack@suse.cz>
---
fs/inode.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/fs/inode.c b/fs/inode.c
index e10145ba2261..89de4cd4e2d8 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1622,17 +1622,21 @@ static int relatime_need_update(const struct path *path, struct inode *inode,
int generic_update_time(struct inode *inode, struct timespec *time, int flags)
{
int iflags = I_DIRTY_TIME;
+ bool dirty = false;
if (flags & S_ATIME)
inode->i_atime = *time;
if (flags & S_VERSION)
- inode_inc_iversion(inode);
+ dirty = inode_maybe_inc_iversion(inode, false);
if (flags & S_CTIME)
inode->i_ctime = *time;
if (flags & S_MTIME)
inode->i_mtime = *time;
+ if ((flags & (S_ATIME | S_CTIME | S_MTIME)) &&
+ !(inode->i_sb->s_flags & MS_LAZYTIME))
+ dirty = true;
- if (!(inode->i_sb->s_flags & MS_LAZYTIME) || (flags & S_VERSION))
+ if (dirty)
iflags |= I_DIRTY_SYNC;
__mark_inode_dirty(inode, iflags);
return 0;
@@ -1851,7 +1855,7 @@ int file_update_time(struct file *file)
if (!timespec_equal(&inode->i_ctime, &now))
sync_it |= S_CTIME;
- if (IS_I_VERSION(inode))
+ if (IS_I_VERSION(inode) && inode_iversion_need_inc(inode))
sync_it |= S_VERSION;
if (!sync_it)
--
2.10.0