Re: [PATCH 5/9] xfs: don't log the inode in xfs_fs_map_blocks if it wasn't modified

Darrick J. Wong
2019-10-30T19:31:58Z

On Wed, Oct 30, 2019 at 11:04:15AM -0700, Christoph Hellwig wrote:
> Even if we are asked for a write layout there is no point in logging
> the inode unless we actually modified it in some way.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks fine...

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

--D

> ---
> fs/xfs/xfs_pnfs.c | 42 ++++++++++++++++++------------------------
> 1 file changed, 18 insertions(+), 24 deletions(-)
>
> diff --git a/fs/xfs/xfs_pnfs.c b/fs/xfs/xfs_pnfs.c
> index 3634ffff3b07..ada46e9f5ff1 100644
> --- a/fs/xfs/xfs_pnfs.c
> +++ b/fs/xfs/xfs_pnfs.c
> @@ -150,30 +150,24 @@ xfs_fs_map_blocks(
>
> ASSERT(!nimaps || imap.br_startblock != DELAYSTARTBLOCK);
>
> - if (write) {
> - enum xfs_prealloc_flags flags = 0;
> -
> - if (!nimaps || imap.br_startblock == HOLESTARTBLOCK) {
> - /*
> - * xfs_iomap_write_direct() expects to take ownership of
> - * the shared ilock.
> - */
> - xfs_ilock(ip, XFS_ILOCK_SHARED);
> - error = xfs_iomap_write_direct(ip, offset, length,
> - &imap, nimaps);
> - if (error)
> - goto out_unlock;
> -
> - /*
> - * Ensure the next transaction is committed
> - * synchronously so that the blocks allocated and
> - * handed out to the client are guaranteed to be
> - * present even after a server crash.
> - */
> - flags |= XFS_PREALLOC_SET | XFS_PREALLOC_SYNC;
> - }
> -
> - error = xfs_update_prealloc_flags(ip, flags);
> + if (write && (!nimaps || imap.br_startblock == HOLESTARTBLOCK)) {
> + /*
> + * xfs_iomap_write_direct() expects to take ownership of the
> + * shared ilock.
> + */
> + xfs_ilock(ip, XFS_ILOCK_SHARED);
> + error = xfs_iomap_write_direct(ip, offset, length, &imap,
> + nimaps);
> + if (error)
> + goto out_unlock;
> +
> + /*
> + * Ensure the next transaction is committed synchronously so
> + * that the blocks allocated and handed out to the client are
> + * guaranteed to be present even after a server crash.
> + */
> + error = xfs_update_prealloc_flags(ip,
> + XFS_PREALLOC_SET | XFS_PREALLOC_SYNC);
> if (error)
> goto out_unlock;
> }
> --
> 2.20.1
>