Re: [PATCH v3 2/4] xfs: Add a comment in xfs_log_sb()

["Darrick J. Wong" <djwong@kernel.org>]

On Thu, Feb 19, 2026 at 08:16:48PM +0530, Nirjhar Roy (IBM) wrote:
> From: "Nirjhar Roy (IBM)" <nirjhar.roy.lists@gmail.com>
> 
> Add a comment explaining why the sb_frextents are updated outside the
> if (xfs_has_lazycount(mp) check even though it is a lazycounter.
> RT groups are supported only in v5 filesystems which always have
> lazycounter enabled - so putting it inside the if(xfs_has_lazycount(mp)
> check is redundant.
> 
> Suggested-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Nirjhar Roy (IBM) <nirjhar.roy.lists@gmail.com>

Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

--D

> ---
>  fs/xfs/libxfs/xfs_sb.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
> index 38d16fe1f6d8..47322adb7690 100644
> --- a/fs/xfs/libxfs/xfs_sb.c
> +++ b/fs/xfs/libxfs/xfs_sb.c
> @@ -1347,6 +1347,9 @@ xfs_log_sb(
>  	 * feature was introduced.  This counter can go negative due to the way
>  	 * we handle nearly-lockless reservations, so we must use the _positive
>  	 * variant here to avoid writing out nonsense frextents.
> +	 *
> +	 * RT groups are only supported on v5 file systems, which always
> +	 * have lazy SB counters.
>  	 */
>  	if (xfs_has_rtgroups(mp) && !xfs_has_zoned(mp)) {
>  		mp->m_sb.sb_frextents =
> -- 
> 2.43.5
> 
>