Re: [PATCH] net/mlx4_core: Use refcount_t for refcount

From: Chuhong Yuan
Date: Fri Aug 02 2019 - 12:11:06 EST


Chuhong Yuan <hslester96@xxxxxxxxx> ä2019å8æ2æåä äå8:10åéï
>
> refcount_t is better for reference counters since its
> implementation can prevent overflows.
> So convert atomic_t ref counters to refcount_t.
>
> Also convert refcount from 0-based to 1-based.
>

It seems that directly converting refcount from 0-based
to 1-based is infeasible.
I am sorry for this mistake.

Regards,
Chuhong

> Signed-off-by: Chuhong Yuan <hslester96@xxxxxxxxx>
> ---
> .../ethernet/mellanox/mlx4/resource_tracker.c | 90 +++++++++----------
> 1 file changed, 45 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
> index 4356f3a58002..d7e26935fd76 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
> @@ -114,7 +114,7 @@ struct res_qp {
> struct list_head mcg_list;
> spinlock_t mcg_spl;
> int local_qpn;
> - atomic_t ref_count;
> + refcount_t ref_count;
> u32 qpc_flags;
> /* saved qp params before VST enforcement in order to restore on VGT */
> u8 sched_queue;
> @@ -143,7 +143,7 @@ static inline const char *mtt_states_str(enum res_mtt_states state)
> struct res_mtt {
> struct res_common com;
> int order;
> - atomic_t ref_count;
> + refcount_t ref_count;
> };
>
> enum res_mpt_states {
> @@ -179,7 +179,7 @@ enum res_cq_states {
> struct res_cq {
> struct res_common com;
> struct res_mtt *mtt;
> - atomic_t ref_count;
> + refcount_t ref_count;
> };
>
> enum res_srq_states {
> @@ -192,7 +192,7 @@ struct res_srq {
> struct res_common com;
> struct res_mtt *mtt;
> struct res_cq *cq;
> - atomic_t ref_count;
> + refcount_t ref_count;
> };
>
> enum res_counter_states {
> @@ -1050,7 +1050,7 @@ static struct res_common *alloc_qp_tr(int id)
> ret->local_qpn = id;
> INIT_LIST_HEAD(&ret->mcg_list);
> spin_lock_init(&ret->mcg_spl);
> - atomic_set(&ret->ref_count, 0);
> + refcount_set(&ret->ref_count, 1);
>
> return &ret->com;
> }
> @@ -1066,7 +1066,7 @@ static struct res_common *alloc_mtt_tr(int id, int order)
> ret->com.res_id = id;
> ret->order = order;
> ret->com.state = RES_MTT_ALLOCATED;
> - atomic_set(&ret->ref_count, 0);
> + refcount_set(&ret->ref_count, 1);
>
> return &ret->com;
> }
> @@ -1110,7 +1110,7 @@ static struct res_common *alloc_cq_tr(int id)
>
> ret->com.res_id = id;
> ret->com.state = RES_CQ_ALLOCATED;
> - atomic_set(&ret->ref_count, 0);
> + refcount_set(&ret->ref_count, 1);
>
> return &ret->com;
> }
> @@ -1125,7 +1125,7 @@ static struct res_common *alloc_srq_tr(int id)
>
> ret->com.res_id = id;
> ret->com.state = RES_SRQ_ALLOCATED;
> - atomic_set(&ret->ref_count, 0);
> + refcount_set(&ret->ref_count, 1);
>
> return &ret->com;
> }
> @@ -1325,10 +1325,10 @@ static int add_res_range(struct mlx4_dev *dev, int slave, u64 base, int count,
>
> static int remove_qp_ok(struct res_qp *res)
> {
> - if (res->com.state == RES_QP_BUSY || atomic_read(&res->ref_count) ||
> + if (res->com.state == RES_QP_BUSY || refcount_read(&res->ref_count) != 1 ||
> !list_empty(&res->mcg_list)) {
> pr_err("resource tracker: fail to remove qp, state %d, ref_count %d\n",
> - res->com.state, atomic_read(&res->ref_count));
> + res->com.state, refcount_read(&res->ref_count));
> return -EBUSY;
> } else if (res->com.state != RES_QP_RESERVED) {
> return -EPERM;
> @@ -1340,11 +1340,11 @@ static int remove_qp_ok(struct res_qp *res)
> static int remove_mtt_ok(struct res_mtt *res, int order)
> {
> if (res->com.state == RES_MTT_BUSY ||
> - atomic_read(&res->ref_count)) {
> + refcount_read(&res->ref_count) != 1) {
> pr_devel("%s-%d: state %s, ref_count %d\n",
> __func__, __LINE__,
> mtt_states_str(res->com.state),
> - atomic_read(&res->ref_count));
> + refcount_read(&res->ref_count));
> return -EBUSY;
> } else if (res->com.state != RES_MTT_ALLOCATED)
> return -EPERM;
> @@ -1675,7 +1675,7 @@ static int cq_res_start_move_to(struct mlx4_dev *dev, int slave, int cqn,
> } else if (state == RES_CQ_ALLOCATED) {
> if (r->com.state != RES_CQ_HW)
> err = -EINVAL;
> - else if (atomic_read(&r->ref_count))
> + else if (refcount_read(&r->ref_count) != 1)
> err = -EBUSY;
> else
> err = 0;
> @@ -1715,7 +1715,7 @@ static int srq_res_start_move_to(struct mlx4_dev *dev, int slave, int index,
> } else if (state == RES_SRQ_ALLOCATED) {
> if (r->com.state != RES_SRQ_HW)
> err = -EINVAL;
> - else if (atomic_read(&r->ref_count))
> + else if (refcount_read(&r->ref_count) != 1)
> err = -EBUSY;
> } else if (state != RES_SRQ_HW || r->com.state != RES_SRQ_ALLOCATED) {
> err = -EINVAL;
> @@ -2808,7 +2808,7 @@ int mlx4_SW2HW_MPT_wrapper(struct mlx4_dev *dev, int slave,
> goto ex_put;
>
> if (!phys) {
> - atomic_inc(&mtt->ref_count);
> + refcount_inc(&mtt->ref_count);
> put_res(dev, slave, mtt->com.res_id, RES_MTT);
> }
>
> @@ -2845,7 +2845,7 @@ int mlx4_HW2SW_MPT_wrapper(struct mlx4_dev *dev, int slave,
> goto ex_abort;
>
> if (mpt->mtt)
> - atomic_dec(&mpt->mtt->ref_count);
> + refcount_dec(&mpt->mtt->ref_count);
>
> res_end_move(dev, slave, RES_MPT, id);
> return 0;
> @@ -3007,18 +3007,18 @@ int mlx4_RST2INIT_QP_wrapper(struct mlx4_dev *dev, int slave,
> err = mlx4_DMA_wrapper(dev, slave, vhcr, inbox, outbox, cmd);
> if (err)
> goto ex_put_srq;
> - atomic_inc(&mtt->ref_count);
> + refcount_inc(&mtt->ref_count);
> qp->mtt = mtt;
> - atomic_inc(&rcq->ref_count);
> + refcount_inc(&rcq->ref_count);
> qp->rcq = rcq;
> - atomic_inc(&scq->ref_count);
> + refcount_inc(&scq->ref_count);
> qp->scq = scq;
>
> if (scqn != rcqn)
> put_res(dev, slave, scqn, RES_CQ);
>
> if (use_srq) {
> - atomic_inc(&srq->ref_count);
> + refcount_inc(&srq->ref_count);
> put_res(dev, slave, srqn, RES_SRQ);
> qp->srq = srq;
> }
> @@ -3113,7 +3113,7 @@ int mlx4_SW2HW_EQ_wrapper(struct mlx4_dev *dev, int slave,
> if (err)
> goto out_put;
>
> - atomic_inc(&mtt->ref_count);
> + refcount_inc(&mtt->ref_count);
> eq->mtt = mtt;
> put_res(dev, slave, mtt->com.res_id, RES_MTT);
> res_end_move(dev, slave, RES_EQ, res_id);
> @@ -3310,7 +3310,7 @@ int mlx4_HW2SW_EQ_wrapper(struct mlx4_dev *dev, int slave,
> if (err)
> goto ex_put;
>
> - atomic_dec(&eq->mtt->ref_count);
> + refcount_dec(&eq->mtt->ref_count);
> put_res(dev, slave, eq->mtt->com.res_id, RES_MTT);
> res_end_move(dev, slave, RES_EQ, res_id);
> rem_res_range(dev, slave, res_id, 1, RES_EQ, 0);
> @@ -3445,7 +3445,7 @@ int mlx4_SW2HW_CQ_wrapper(struct mlx4_dev *dev, int slave,
> err = mlx4_DMA_wrapper(dev, slave, vhcr, inbox, outbox, cmd);
> if (err)
> goto out_put;
> - atomic_inc(&mtt->ref_count);
> + refcount_inc(&mtt->ref_count);
> cq->mtt = mtt;
> put_res(dev, slave, mtt->com.res_id, RES_MTT);
> res_end_move(dev, slave, RES_CQ, cqn);
> @@ -3474,7 +3474,7 @@ int mlx4_HW2SW_CQ_wrapper(struct mlx4_dev *dev, int slave,
> err = mlx4_DMA_wrapper(dev, slave, vhcr, inbox, outbox, cmd);
> if (err)
> goto out_move;
> - atomic_dec(&cq->mtt->ref_count);
> + refcount_dec(&cq->mtt->ref_count);
> res_end_move(dev, slave, RES_CQ, cqn);
> return 0;
>
> @@ -3539,9 +3539,9 @@ static int handle_resize(struct mlx4_dev *dev, int slave,
> err = mlx4_DMA_wrapper(dev, slave, vhcr, inbox, outbox, cmd);
> if (err)
> goto ex_put1;
> - atomic_dec(&orig_mtt->ref_count);
> + refcount_dec(&orig_mtt->ref_count);
> put_res(dev, slave, orig_mtt->com.res_id, RES_MTT);
> - atomic_inc(&mtt->ref_count);
> + refcount_inc(&mtt->ref_count);
> cq->mtt = mtt;
> put_res(dev, slave, mtt->com.res_id, RES_MTT);
> return 0;
> @@ -3627,7 +3627,7 @@ int mlx4_SW2HW_SRQ_wrapper(struct mlx4_dev *dev, int slave,
> if (err)
> goto ex_put_mtt;
>
> - atomic_inc(&mtt->ref_count);
> + refcount_inc(&mtt->ref_count);
> srq->mtt = mtt;
> put_res(dev, slave, mtt->com.res_id, RES_MTT);
> res_end_move(dev, slave, RES_SRQ, srqn);
> @@ -3657,9 +3657,9 @@ int mlx4_HW2SW_SRQ_wrapper(struct mlx4_dev *dev, int slave,
> err = mlx4_DMA_wrapper(dev, slave, vhcr, inbox, outbox, cmd);
> if (err)
> goto ex_abort;
> - atomic_dec(&srq->mtt->ref_count);
> + refcount_dec(&srq->mtt->ref_count);
> if (srq->cq)
> - atomic_dec(&srq->cq->ref_count);
> + refcount_dec(&srq->cq->ref_count);
> res_end_move(dev, slave, RES_SRQ, srqn);
>
> return 0;
> @@ -3988,11 +3988,11 @@ int mlx4_2RST_QP_wrapper(struct mlx4_dev *dev, int slave,
> if (err)
> goto ex_abort;
>
> - atomic_dec(&qp->mtt->ref_count);
> - atomic_dec(&qp->rcq->ref_count);
> - atomic_dec(&qp->scq->ref_count);
> + refcount_dec(&qp->mtt->ref_count);
> + refcount_dec(&qp->rcq->ref_count);
> + refcount_dec(&qp->scq->ref_count);
> if (qp->srq)
> - atomic_dec(&qp->srq->ref_count);
> + refcount_dec(&qp->srq->ref_count);
> res_end_move(dev, slave, RES_QP, qpn);
> return 0;
>
> @@ -4456,7 +4456,7 @@ int mlx4_QP_FLOW_STEERING_ATTACH_wrapper(struct mlx4_dev *dev, int slave,
> if (mlx4_is_bonded(dev))
> mlx4_do_mirror_rule(dev, rrule);
>
> - atomic_inc(&rqp->ref_count);
> + refcount_inc(&rqp->ref_count);
>
> err_put_rule:
> put_res(dev, slave, vhcr->out_param, RES_FS_RULE);
> @@ -4540,7 +4540,7 @@ int mlx4_QP_FLOW_STEERING_DETACH_wrapper(struct mlx4_dev *dev, int slave,
> MLX4_QP_FLOW_STEERING_DETACH, MLX4_CMD_TIME_CLASS_A,
> MLX4_CMD_NATIVE);
> if (!err)
> - atomic_dec(&rqp->ref_count);
> + refcount_dec(&rqp->ref_count);
> out:
> put_res(dev, slave, qpn, RES_QP);
> return err;
> @@ -4702,11 +4702,11 @@ static void rem_slave_qps(struct mlx4_dev *dev, int slave)
> if (err)
> mlx4_dbg(dev, "rem_slave_qps: failed to move slave %d qpn %d to reset\n",
> slave, qp->local_qpn);
> - atomic_dec(&qp->rcq->ref_count);
> - atomic_dec(&qp->scq->ref_count);
> - atomic_dec(&qp->mtt->ref_count);
> + refcount_dec(&qp->rcq->ref_count);
> + refcount_dec(&qp->scq->ref_count);
> + refcount_dec(&qp->mtt->ref_count);
> if (qp->srq)
> - atomic_dec(&qp->srq->ref_count);
> + refcount_dec(&qp->srq->ref_count);
> state = RES_QP_MAPPED;
> break;
> default:
> @@ -4768,9 +4768,9 @@ static void rem_slave_srqs(struct mlx4_dev *dev, int slave)
> mlx4_dbg(dev, "rem_slave_srqs: failed to move slave %d srq %d to SW ownership\n",
> slave, srqn);
>
> - atomic_dec(&srq->mtt->ref_count);
> + refcount_dec(&srq->mtt->ref_count);
> if (srq->cq)
> - atomic_dec(&srq->cq->ref_count);
> + refcount_dec(&srq->cq->ref_count);
> state = RES_SRQ_ALLOCATED;
> break;
>
> @@ -4805,7 +4805,7 @@ static void rem_slave_cqs(struct mlx4_dev *dev, int slave)
> spin_lock_irq(mlx4_tlock(dev));
> list_for_each_entry_safe(cq, tmp, cq_list, com.list) {
> spin_unlock_irq(mlx4_tlock(dev));
> - if (cq->com.owner == slave && !atomic_read(&cq->ref_count)) {
> + if (cq->com.owner == slave && refcount_read(&cq->ref_count) == 1) {
> cqn = cq->com.res_id;
> state = cq->com.from_state;
> while (state != 0) {
> @@ -4832,7 +4832,7 @@ static void rem_slave_cqs(struct mlx4_dev *dev, int slave)
> if (err)
> mlx4_dbg(dev, "rem_slave_cqs: failed to move slave %d cq %d to SW ownership\n",
> slave, cqn);
> - atomic_dec(&cq->mtt->ref_count);
> + refcount_dec(&cq->mtt->ref_count);
> state = RES_CQ_ALLOCATED;
> break;
>
> @@ -4900,7 +4900,7 @@ static void rem_slave_mrs(struct mlx4_dev *dev, int slave)
> mlx4_dbg(dev, "rem_slave_mrs: failed to move slave %d mpt %d to SW ownership\n",
> slave, mptn);
> if (mpt->mtt)
> - atomic_dec(&mpt->mtt->ref_count);
> + refcount_dec(&mpt->mtt->ref_count);
> state = RES_MPT_MAPPED;
> break;
> default:
> @@ -5144,7 +5144,7 @@ static void rem_slave_eqs(struct mlx4_dev *dev, int slave)
> if (err)
> mlx4_dbg(dev, "rem_slave_eqs: failed to move slave %d eqs %d to SW ownership\n",
> slave, eqn & 0x3ff);
> - atomic_dec(&eq->mtt->ref_count);
> + refcount_dec(&eq->mtt->ref_count);
> state = RES_EQ_RESERVED;
> break;
>
> --
> 2.20.1
>