Re: [PATCH] xfs: only bother with sync_filesystem during readonly remount

[Dave Chinner <david@fromorbit.com>]

On Tue, Feb 08, 2022 at 12:09:08PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@kernel.org>
> 
> In commit 02b9984d6408, we pushed a sync_filesystem() call from the VFS
> into xfs_fs_remount.  The only time that we ever need to push dirty file
> data or metadata to disk for a remount is if we're remounting the
> filesystem read only, so this really could be moved to xfs_remount_ro.
> 
> Once we've moved the call site, actually check the return value from
> sync_filesystem.
> 
> Fixes: 02b9984d6408 ("fs: push sync_filesystem() down to the file system's remount_fs()")
> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> ---
>  fs/xfs/xfs_super.c |    7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index 4c0dee78b2f8..d84714e4e46a 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -1753,6 +1753,11 @@ xfs_remount_ro(
>  	};
>  	int			error;
>  
> +	/* Flush all the dirty data to disk. */
> +	error = sync_filesystem(mp->m_super);
> +	if (error)
> +		return error;
> +
>  	/*
>  	 * Cancel background eofb scanning so it cannot race with the final
>  	 * log force+buftarg wait and deadlock the remount.
> @@ -1831,8 +1836,6 @@ xfs_fs_reconfigure(
>  	if (error)
>  		return error;
>  
> -	sync_filesystem(mp->m_super);
> -
>  	/* inode32 -> inode64 */
>  	if (xfs_has_small_inums(mp) && !xfs_has_small_inums(new_mp)) {
>  		mp->m_features &= ~XFS_FEAT_SMALL_INUMS;

Looks ok.

Reviewed-by: Dave Chinner <dchinner@redhat.com>

-- 
Dave Chinner
david@fromorbit.com