From: Leon Romanovsky <leonro@nvidia.com>
Date: Fri, 23 Jul 2021 14:39:47 +0300
Subject: RDMA/mlx5: Delete device resource mutex that didn't protect anything
Patch-mainline: v5.15-rc1
Git-commit: 8c9e7f0325fe57ef55bacfa82d10857b4433fef3
References: jsc#SLE-19250
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: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/infiniband/hw/mlx5/gsi.c | 34 +++++++++-------------------------
drivers/infiniband/hw/mlx5/main.c | 9 +++++++--
drivers/infiniband/hw/mlx5/mlx5_ib.h | 2 --
3 files changed, 16 insertions(+), 29 deletions(-)
--- a/drivers/infiniband/hw/mlx5/gsi.c
+++ b/drivers/infiniband/hw/mlx5/gsi.c
@@ -116,8 +116,6 @@ int mlx5_ib_create_gsi(struct ib_pd *pd,
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,
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_q
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 @@ err_destroy_qp:
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 *
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 *
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);
}
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -2511,6 +2511,13 @@ static void pkey_change_handler(struct w
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);
}
@@ -2805,8 +2812,6 @@ static int mlx5_ib_dev_res_init(struct m
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;
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -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 {