Re: [PATCH 16/18] xfs: move quota locking into xrep_quota_item

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

On Mon, Nov 10, 2025 at 02:23:08PM +0100, Christoph Hellwig wrote:
> Drop two redundant lock roundtrips by not requiring q_lock to be held on
> entry and return.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Same here! :)
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

--D

> ---
>  fs/xfs/scrub/quota_repair.c | 16 ++++++----------
>  1 file changed, 6 insertions(+), 10 deletions(-)
> 
> diff --git a/fs/xfs/scrub/quota_repair.c b/fs/xfs/scrub/quota_repair.c
> index dae4889bdc84..b1d661aa5f06 100644
> --- a/fs/xfs/scrub/quota_repair.c
> +++ b/fs/xfs/scrub/quota_repair.c
> @@ -184,17 +184,13 @@ xrep_quota_item(
>  	/*
>  	 * We might need to fix holes in the bmap record for the storage
>  	 * backing this dquot, so we need to lock the dquot and the quota file.
> -	 * dqiterate gave us a locked dquot, so drop the dquot lock to get the
> -	 * ILOCK_EXCL.
>  	 */
> -	mutex_unlock(&dq->q_qlock);
>  	xchk_ilock(sc, XFS_ILOCK_EXCL);
>  	mutex_lock(&dq->q_qlock);
> -
>  	error = xrep_quota_item_bmap(sc, dq, &dirty);
>  	xchk_iunlock(sc, XFS_ILOCK_EXCL);
>  	if (error)
> -		return error;
> +		goto out_unlock_dquot;
>  
>  	/* Check the limits. */
>  	if (dq->q_blk.softlimit > dq->q_blk.hardlimit) {
> @@ -246,7 +242,7 @@ xrep_quota_item(
>  	xrep_quota_item_timer(sc, &dq->q_rtb, &dirty);
>  
>  	if (!dirty)
> -		return 0;
> +		goto out_unlock_dquot;
>  
>  	trace_xrep_dquot_item(sc->mp, dq->q_type, dq->q_id);
>  
> @@ -257,8 +253,10 @@ xrep_quota_item(
>  		xfs_qm_adjust_dqtimers(dq);
>  	}
>  	xfs_trans_log_dquot(sc->tp, dq);
> -	error = xfs_trans_roll(&sc->tp);
> -	mutex_lock(&dq->q_qlock);
> +	return xfs_trans_roll(&sc->tp);
> +
> +out_unlock_dquot:
> +	mutex_unlock(&dq->q_qlock);
>  	return error;
>  }
>  
> @@ -512,9 +510,7 @@ xrep_quota_problems(
>  
>  	xchk_dqiter_init(&cursor, sc, dqtype);
>  	while ((error = xchk_dquot_iter(&cursor, &dq)) == 1) {
> -		mutex_lock(&dq->q_qlock);
>  		error = xrep_quota_item(&rqi, dq);
> -		mutex_unlock(&dq->q_qlock);
>  		xfs_qm_dqrele(dq);
>  		if (error)
>  			break;
> -- 
> 2.47.3
> 
>