On Tuesday 30 June 2020 9:13:38 PM IST Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
>
> Hoist the code that adjusts the incore quota reservation count
> adjustments into a separate function, both to reduce the level of
> indentation and also to reduce the amount of open-coded logic.
>
The changes are logically consistent with the previous behaviour.
Reviewed-by: Chandan Babu R <chandanrlinux@xxxxxxxxx>
> Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> ---
> fs/xfs/xfs_trans_dquot.c | 103 +++++++++++++++++++++-------------------------
> 1 file changed, 46 insertions(+), 57 deletions(-)
>
>
> diff --git a/fs/xfs/xfs_trans_dquot.c b/fs/xfs/xfs_trans_dquot.c
> index 30a011dc9828..701923ea6c04 100644
> --- a/fs/xfs/xfs_trans_dquot.c
> +++ b/fs/xfs/xfs_trans_dquot.c
> @@ -293,6 +293,37 @@ xfs_trans_dqlockedjoin(
> }
> }
>
> +/* Apply dqtrx changes to the quota reservation counters. */
> +static inline void
> +xfs_apply_quota_reservation_deltas(
> + struct xfs_dquot_res *res,
> + uint64_t reserved,
> + int64_t res_used,
> + int64_t count_delta)
> +{
> + if (reserved != 0) {
> + /*
> + * Subtle math here: If reserved > res_used (the normal case),
> + * we're simply subtracting the unused transaction quota
> + * reservation from the dquot reservation.
> + *
> + * If, however, res_used > reserved, then we have allocated
> + * more quota blocks than were reserved for the transaction.
> + * We must add that excess to the dquot reservation since it
> + * tracks (usage + resv) and by definition we didn't reserve
> + * that excess.
> + */
> + res->reserved -= abs(reserved - res_used);
> + } else if (count_delta != 0) {
> + /*
> + * These blks were never reserved, either inside a transaction
> + * or outside one (in a delayed allocation). Also, this isn't
> + * always a negative number since we sometimes deliberately
> + * skip quota reservations.
> + */
> + res->reserved += count_delta;
> + }
> +}
>
> /*
> * Called by xfs_trans_commit() and similar in spirit to
> @@ -327,6 +358,8 @@ xfs_trans_apply_dquot_deltas(
> xfs_trans_dqlockedjoin(tp, qa);
>
> for (i = 0; i < XFS_QM_TRANS_MAXDQS; i++) {
> + uint64_t blk_res_used;
> +
> qtrx = &qa[i];
> /*
> * The array of dquots is filled
> @@ -396,71 +429,27 @@ xfs_trans_apply_dquot_deltas(
> * In case of delayed allocations, there's no
> * reservation that a transaction structure knows of.
> */
> - if (qtrx->qt_blk_res != 0) {
> - uint64_t blk_res_used = 0;
> + blk_res_used = max_t(int64_t, 0, qtrx->qt_bcount_delta);
> + xfs_apply_quota_reservation_deltas(&dqp->q_blk,
> + qtrx->qt_blk_res, blk_res_used,
> + qtrx->qt_bcount_delta);
>
> - if (qtrx->qt_bcount_delta > 0)
> - blk_res_used = qtrx->qt_bcount_delta;
> -
> - if (qtrx->qt_blk_res != blk_res_used) {
> - if (qtrx->qt_blk_res > blk_res_used)
> - dqp->q_blk.reserved -= (xfs_qcnt_t)
> - (qtrx->qt_blk_res -
> - blk_res_used);
> - else
> - dqp->q_blk.reserved -= (xfs_qcnt_t)
> - (blk_res_used -
> - qtrx->qt_blk_res);
> - }
> - } else {
> - /*
> - * These blks were never reserved, either inside
> - * a transaction or outside one (in a delayed
> - * allocation). Also, this isn't always a
> - * negative number since we sometimes
> - * deliberately skip quota reservations.
> - */
> - if (qtrx->qt_bcount_delta) {
> - dqp->q_blk.reserved +=
> - (xfs_qcnt_t)qtrx->qt_bcount_delta;
> - }
> - }
> /*
> * Adjust the RT reservation.
> */
> - if (qtrx->qt_rtblk_res != 0) {
> - if (qtrx->qt_rtblk_res != qtrx->qt_rtblk_res_used) {
> - if (qtrx->qt_rtblk_res >
> - qtrx->qt_rtblk_res_used)
> - dqp->q_rtb.reserved -= (xfs_qcnt_t)
> - (qtrx->qt_rtblk_res -
> - qtrx->qt_rtblk_res_used);
> - else
> - dqp->q_rtb.reserved -= (xfs_qcnt_t)
> - (qtrx->qt_rtblk_res_used -
> - qtrx->qt_rtblk_res);
> - }
> - } else {
> - if (qtrx->qt_rtbcount_delta)
> - dqp->q_rtb.reserved +=
> - (xfs_qcnt_t)qtrx->qt_rtbcount_delta;
> - }
> + xfs_apply_quota_reservation_deltas(&dqp->q_rtb,
> + qtrx->qt_rtblk_res,
> + qtrx->qt_rtblk_res_used,
> + qtrx->qt_rtbcount_delta);
>
> /*
> * Adjust the inode reservation.
> */
> - if (qtrx->qt_ino_res != 0) {
> - ASSERT(qtrx->qt_ino_res >=
> - qtrx->qt_ino_res_used);
> - if (qtrx->qt_ino_res > qtrx->qt_ino_res_used)
> - dqp->q_ino.reserved -= (xfs_qcnt_t)
> - (qtrx->qt_ino_res -
> - qtrx->qt_ino_res_used);
> - } else {
> - if (qtrx->qt_icount_delta)
> - dqp->q_ino.reserved +=
> - (xfs_qcnt_t)qtrx->qt_icount_delta;
> - }
> + ASSERT(qtrx->qt_ino_res >= qtrx->qt_ino_res_used);
> + xfs_apply_quota_reservation_deltas(&dqp->q_ino,
> + qtrx->qt_ino_res,
> + qtrx->qt_ino_res_used,
> + qtrx->qt_icount_delta);
>
> ASSERT(dqp->q_blk.reserved >= dqp->q_blk.count);
> ASSERT(dqp->q_ino.reserved >= dqp->q_ino.count);
>
>
--
chandan
