Commit 8c9e7f03 authored by Leon Romanovsky's avatar Leon Romanovsky Committed by Jason Gunthorpe
Browse files

RDMA/mlx5: Delete device resource mutex that didn't protect anything 

The dev->devr.mutex was intended to protect GSI QP pointer change in the
struct mlx5_ib_port_resources when it is accessed from the
pkey_change_work. However that pointer isn't changed during the runtime
and once IB/core adds MAD, it stays stable.

Link: https://lore.kernel.org/r/6e338c561033df20d92e1371fc6a7a0d93aad945.1627040189.git.leonro@nvidia.com


Signed-off-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent b0791dbf

drivers/infiniband/hw/mlx5/gsi.c

+9 −25
Original line number Diff line number Diff line
@@ -116,8 +116,6 @@ int mlx5_ib_create_gsi(struct ib_pd *pd, struct mlx5_ib_qp *mqp, 
		goto err_free_tx;

	}



	mutex_lock(&dev->devr.mutex);



	if (dev->devr.ports[port_num - 1].gsi) {

		mlx5_ib_warn(dev, "GSI QP already exists on port %d\n",

			     port_num);
@@ -167,15 +165,11 @@ int mlx5_ib_create_gsi(struct ib_pd *pd, struct mlx5_ib_qp *mqp, 
	INIT_LIST_HEAD(&gsi->rx_qp->sig_mrs);



	dev->devr.ports[attr->port_num - 1].gsi = gsi;



	mutex_unlock(&dev->devr.mutex);



	return 0;



err_destroy_cq:

	ib_free_cq(gsi->cq);

err_free_wrs:

	mutex_unlock(&dev->devr.mutex);

	kfree(gsi->outstanding_wrs);

err_free_tx:

	kfree(gsi->tx_qps);
@@ -190,16 +184,13 @@ int mlx5_ib_destroy_gsi(struct mlx5_ib_qp *mqp) 
	int qp_index;

	int ret;



	mutex_lock(&dev->devr.mutex);

	ret = mlx5_ib_destroy_qp(gsi->rx_qp, NULL);

	if (ret) {

		mlx5_ib_warn(dev, "unable to destroy hardware GSI QP. error %d\n",

			     ret);

		mutex_unlock(&dev->devr.mutex);

		return ret;

	}

	dev->devr.ports[port_num - 1].gsi = NULL;

	mutex_unlock(&dev->devr.mutex);

	gsi->rx_qp = NULL;



	for (qp_index = 0; qp_index < gsi->num_qps; ++qp_index) {
@@ -339,23 +330,13 @@ static void setup_qp(struct mlx5_ib_gsi_qp *gsi, u16 qp_index) 
	WARN_ON_ONCE(qp);

}



static void setup_qps(struct mlx5_ib_gsi_qp *gsi)

{

	struct mlx5_ib_dev *dev = to_mdev(gsi->rx_qp->device);

	u16 qp_index;



	mutex_lock(&dev->devr.mutex);

	for (qp_index = 0; qp_index < gsi->num_qps; ++qp_index)

		setup_qp(gsi, qp_index);

	mutex_unlock(&dev->devr.mutex);

}



int mlx5_ib_gsi_modify_qp(struct ib_qp *qp, struct ib_qp_attr *attr,

			  int attr_mask)

{

	struct mlx5_ib_dev *dev = to_mdev(qp->device);

	struct mlx5_ib_qp *mqp = to_mqp(qp);

	struct mlx5_ib_gsi_qp *gsi = &mqp->gsi;

	u16 qp_index;

	int ret;



	mlx5_ib_dbg(dev, "modifying GSI QP to state %d\n", attr->qp_state);
@@ -366,8 +347,11 @@ int mlx5_ib_gsi_modify_qp(struct ib_qp *qp, struct ib_qp_attr *attr, 
		return ret;

	}



	if (to_mqp(gsi->rx_qp)->state == IB_QPS_RTS)

		setup_qps(gsi);

	if (to_mqp(gsi->rx_qp)->state != IB_QPS_RTS)

		return 0;



	for (qp_index = 0; qp_index < gsi->num_qps; ++qp_index)

		setup_qp(gsi, qp_index);

	return 0;

}
@@ -511,8 +495,8 @@ int mlx5_ib_gsi_post_recv(struct ib_qp *qp, const struct ib_recv_wr *wr, 


void mlx5_ib_gsi_pkey_change(struct mlx5_ib_gsi_qp *gsi)

{

	if (!gsi)

		return;

	u16 qp_index;



	setup_qps(gsi);

	for (qp_index = 0; qp_index < gsi->num_qps; ++qp_index)

		setup_qp(gsi, qp_index);

}

drivers/infiniband/hw/mlx5/main.c

+7 −2
Original line number Diff line number Diff line
@@ -2501,6 +2501,13 @@ static void pkey_change_handler(struct work_struct *work) 
		container_of(work, struct mlx5_ib_port_resources,

			     pkey_change_work);



	if (!ports->gsi)

		/*

		 * We got this event before device was fully configured

		 * and MAD registration code wasn't called/finished yet.

		 */

		return;



	mlx5_ib_gsi_pkey_change(ports->gsi);

}
@@ -2795,8 +2802,6 @@ static int mlx5_ib_dev_res_init(struct mlx5_ib_dev *dev) 
	if (!MLX5_CAP_GEN(dev->mdev, xrc))

		return -EOPNOTSUPP;



	mutex_init(&devr->mutex);



	devr->p0 = rdma_zalloc_drv_obj(ibdev, ib_pd);

	if (!devr->p0)

		return -ENOMEM;

drivers/infiniband/hw/mlx5/mlx5_ib.h

+0 −2
Original line number Diff line number Diff line
@@ -795,8 +795,6 @@ struct mlx5_ib_resources { 
	struct ib_srq	*s0;

	struct ib_srq	*s1;

	struct mlx5_ib_port_resources ports[2];

	/* Protects changes to the port resources */

	struct mutex	mutex;

};



struct mlx5_ib_counters {