[PATCH 5/8] xfs: log timestamp updates

[Mark Tinguely]

On 02/29/12 03:53, Christoph Hellwig wrote:
> Timestamps on regular files are the last metadata that XFS does not update
> transactionally.  Now that we use the delaylog mode exclusively and made
> the log scode scale extremly well there is no need to bypass that code for
> timestamp updates.  Logging all updates allows to drop a lot of code, and
> will allow for further performance improvements later on.
>
> Note that this patch drops optimized handling of fdatasync - it will be
> added back in a separate commit.
>
> Reviewed-by: Dave Chinner<dchinner at redhat.com>
> Signed-off-by: Christoph Hellwig<hch at lst.de>
>
> ---
...

> @@ -659,9 +598,6 @@ restart:
>   		return error;
>   	}
>
> -	if (likely(!(file->f_mode&  FMODE_NOCMTIME)))
> -		file_update_time(file);
> -
>   	/*
>   	 * If the offset is beyond the size of the file, we need to zero any
>   	 * blocks that fall between the existing EOF and the start of this
> @@ -685,6 +621,15 @@ restart:
>   		return error;
>
>   	/*
> +	 * Updating the timestamps will grab the ilock again from
> +	 * xfs_fs_dirty_inode, so we have to call it after dropping the
> +	 * lock above.  Eventually we should look into a way to avoid
> +	 * the pointless lock roundtrip.
> +	 */
> +	if (likely(!(file->f_mode&  FMODE_NOCMTIME)))
> +		file_update_time(file);
> +

I see the inode timestamp update was taken out of the dio path. Are 
those being updated in xfs_trans_ichgtime()?

Reviewed-by: Mark Tinguely