Re: [PATCH 03/12] xfs: cleanup calculating the stat optimal I/O size

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Sun, Oct 27, 2019 at 03:55:38PM +0100, Christoph Hellwig wrote:
> Move xfs_preferred_iosize to xfs_iops.c, unobsfucate it and also handle
> the realtime special case in the helper.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Eric Sandeen <sandeen@redhat.com>

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

--D

> ---
>  fs/xfs/xfs_iops.c  | 47 ++++++++++++++++++++++++++++++++++++----------
>  fs/xfs/xfs_mount.h | 24 -----------------------
>  2 files changed, 37 insertions(+), 34 deletions(-)
> 
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index 404f2dd58698..b6dbfd8eb6a1 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -484,6 +484,42 @@ xfs_vn_get_link_inline(
>  	return link;
>  }
>  
> +static uint32_t
> +xfs_stat_blksize(
> +	struct xfs_inode	*ip)
> +{
> +	struct xfs_mount	*mp = ip->i_mount;
> +
> +	/*
> +	 * If the file blocks are being allocated from a realtime volume, then
> +	 * always return the realtime extent size.
> +	 */
> +	if (XFS_IS_REALTIME_INODE(ip))
> +		return xfs_get_extsz_hint(ip) << mp->m_sb.sb_blocklog;
> +
> +	/*
> +	 * Allow large block sizes to be reported to userspace programs if the
> +	 * "largeio" mount option is used.
> +	 *
> +	 * If compatibility mode is specified, simply return the basic unit of
> +	 * caching so that we don't get inefficient read/modify/write I/O from
> +	 * user apps. Otherwise....
> +	 *
> +	 * If the underlying volume is a stripe, then return the stripe width in
> +	 * bytes as the recommended I/O size. It is not a stripe and we've set a
> +	 * default buffered I/O size, return that, otherwise return the compat
> +	 * default.
> +	 */
> +	if (!(mp->m_flags & XFS_MOUNT_COMPAT_IOSIZE)) {
> +		if (mp->m_swidth)
> +			return mp->m_swidth << mp->m_sb.sb_blocklog;
> +		if (mp->m_flags & XFS_MOUNT_DFLT_IOSIZE)
> +			return 1U << max(mp->m_readio_log, mp->m_writeio_log);
> +	}
> +
> +	return PAGE_SIZE;
> +}
> +
>  STATIC int
>  xfs_vn_getattr(
>  	const struct path	*path,
> @@ -543,16 +579,7 @@ xfs_vn_getattr(
>  		stat->rdev = inode->i_rdev;
>  		break;
>  	default:
> -		if (XFS_IS_REALTIME_INODE(ip)) {
> -			/*
> -			 * If the file blocks are being allocated from a
> -			 * realtime volume, then return the inode's realtime
> -			 * extent size or the realtime volume's extent size.
> -			 */
> -			stat->blksize =
> -				xfs_get_extsz_hint(ip) << mp->m_sb.sb_blocklog;
> -		} else
> -			stat->blksize = xfs_preferred_iosize(mp);
> +		stat->blksize = xfs_stat_blksize(ip);
>  		stat->rdev = 0;
>  		break;
>  	}
> diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
> index fdb60e09a9c5..f69e370db341 100644
> --- a/fs/xfs/xfs_mount.h
> +++ b/fs/xfs/xfs_mount.h
> @@ -267,30 +267,6 @@ typedef struct xfs_mount {
>  #define	XFS_WSYNC_READIO_LOG	15	/* 32k */
>  #define	XFS_WSYNC_WRITEIO_LOG	14	/* 16k */
>  
> -/*
> - * Allow large block sizes to be reported to userspace programs if the
> - * "largeio" mount option is used.
> - *
> - * If compatibility mode is specified, simply return the basic unit of caching
> - * so that we don't get inefficient read/modify/write I/O from user apps.
> - * Otherwise....
> - *
> - * If the underlying volume is a stripe, then return the stripe width in bytes
> - * as the recommended I/O size. It is not a stripe and we've set a default
> - * buffered I/O size, return that, otherwise return the compat default.
> - */
> -static inline unsigned long
> -xfs_preferred_iosize(xfs_mount_t *mp)
> -{
> -	if (mp->m_flags & XFS_MOUNT_COMPAT_IOSIZE)
> -		return PAGE_SIZE;
> -	return (mp->m_swidth ?
> -		(mp->m_swidth << mp->m_sb.sb_blocklog) :
> -		((mp->m_flags & XFS_MOUNT_DFLT_IOSIZE) ?
> -			(1 << (int)max(mp->m_readio_log, mp->m_writeio_log)) :
> -			PAGE_SIZE));
> -}
> -
>  #define XFS_LAST_UNMOUNT_WAS_CLEAN(mp)	\
>  				((mp)->m_flags & XFS_MOUNT_WAS_CLEAN)
>  #define XFS_FORCED_SHUTDOWN(mp)	((mp)->m_flags & XFS_MOUNT_FS_SHUTDOWN)
> -- 
> 2.20.1
>