[PATCH rdma-next v2 07/14] IB/mlx5: Move IB event processing onto a workqueue

Leon Romanovsky
2018-01-04T15:25:37Z

Because mlx5_ib_event can be called from atomic context move event
handling onto a workqueue. A mutex lock is required to get the IB device
for slave ports, so move event processing onto a work queue. When an IB
event is received, check if the mlx5_core_dev is a slave port, if so
attempt to get the IB device it's affiliated with. If found process the
event for that device, otherwise return.

Signed-off-by: Daniel Jurgens <danielj-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
Reviewed-by: Parav Pandit <parav-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
Signed-off-by: Leon Romanovsky <leon-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
---
drivers/infiniband/hw/mlx5/main.c | 69 +++++++++++++++++++++++++++++++--------
1 file changed, 56 insertions(+), 13 deletions(-)

diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 4fbbe4c7a99b..0ff6da1b885f 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -70,10 +70,19 @@ static char mlx5_version[] =
DRIVER_NAME ": Mellanox Connect-IB Infiniband driver v"
DRIVER_VERSION "\n";

+struct mlx5_ib_event_work {
+ struct work_struct work;
+ struct mlx5_core_dev *dev;
+ void *context;
+ enum mlx5_dev_event event;
+ unsigned long param;
+};
+
enum {
MLX5_ATOMIC_SIZE_QP_8BYTES = 1 << 3,
};

+static struct workqueue_struct *mlx5_ib_event_wq;
static LIST_HEAD(mlx5_ib_unaffiliated_port_list);
static LIST_HEAD(mlx5_ib_dev_list);
/*
@@ -3132,15 +3141,24 @@ static void delay_drop_handler(struct work_struct *work)
mutex_unlock(&delay_drop->lock);
}

-static void mlx5_ib_event(struct mlx5_core_dev *dev, void *context,
- enum mlx5_dev_event event, unsigned long param)
+static void mlx5_ib_handle_event(struct work_struct *_work)
{
- struct mlx5_ib_dev *ibdev = (struct mlx5_ib_dev *)context;
+ struct mlx5_ib_event_work *work =
+ container_of(_work, struct mlx5_ib_event_work, work);
+ struct mlx5_ib_dev *ibdev;
struct ib_event ibev;
bool fatal = false;
u8 port = 0;

- switch (event) {
+ if (mlx5_core_is_mp_slave(work->dev)) {
+ ibdev = mlx5_ib_get_ibdev_from_mpi(work->context);
+ if (!ibdev)
+ goto out;
+ } else {
+ ibdev = work->context;
+ }
+
+ switch (work->event) {
case MLX5_DEV_EVENT_SYS_ERROR:
ibev.event = IB_EVENT_DEVICE_FATAL;
mlx5_ib_handle_internal_error(ibdev);
@@ -3150,39 +3168,39 @@ static void mlx5_ib_event(struct mlx5_core_dev *dev, void *context,
case MLX5_DEV_EVENT_PORT_UP:
case MLX5_DEV_EVENT_PORT_DOWN:
case MLX5_DEV_EVENT_PORT_INITIALIZED:
- port = (u8)param;
+ port = (u8)work->param;

/* In RoCE, port up/down events are handled in
* mlx5_netdev_event().
*/
if (mlx5_ib_port_link_layer(&ibdev->ib_dev, port) ==
IB_LINK_LAYER_ETHERNET)
- return;
+ goto out;

- ibev.event = (event == MLX5_DEV_EVENT_PORT_UP) ?
+ ibev.event = (work->event == MLX5_DEV_EVENT_PORT_UP) ?
IB_EVENT_PORT_ACTIVE : IB_EVENT_PORT_ERR;
break;

case MLX5_DEV_EVENT_LID_CHANGE:
ibev.event = IB_EVENT_LID_CHANGE;
- port = (u8)param;
+ port = (u8)work->param;
break;

case MLX5_DEV_EVENT_PKEY_CHANGE:
ibev.event = IB_EVENT_PKEY_CHANGE;
- port = (u8)param;
+ port = (u8)work->param;

schedule_work(&ibdev->devr.ports[port - 1].pkey_change_work);
break;

case MLX5_DEV_EVENT_GUID_CHANGE:
ibev.event = IB_EVENT_GID_CHANGE;
- port = (u8)param;
+ port = (u8)work->param;
break;

case MLX5_DEV_EVENT_CLIENT_REREG:
ibev.event = IB_EVENT_CLIENT_REREGISTER;
- port = (u8)param;
+ port = (u8)work->param;
break;
case MLX5_DEV_EVENT_DELAY_DROP_TIMEOUT:
schedule_work(&ibdev->delay_drop.delay_drop_work);
@@ -3204,9 +3222,29 @@ static void mlx5_ib_event(struct mlx5_core_dev *dev, void *context,

if (fatal)
ibdev->ib_active = false;
-
out:
- return;
+ kfree(work);
+}
+
+static void mlx5_ib_event(struct mlx5_core_dev *dev, void *context,
+ enum mlx5_dev_event event, unsigned long param)
+{
+ struct mlx5_ib_event_work *work;
+
+ work = kmalloc(sizeof(*work), GFP_ATOMIC);
+ if (work) {
+ INIT_WORK(&work->work, mlx5_ib_handle_event);
+ work->dev = dev;
+ work->param = param;
+ work->context = context;
+ work->event = event;
+
+ queue_work(mlx5_ib_event_wq, &work->work);
+ return;
+ }
+
+ dev_warn(&dev->pdev->dev, "%s: mlx5_dev_event: %d, with param: %lu dropped, couldn't allocate memory.\n",
+ __func__, event, param);
}

static int set_has_smi_cap(struct mlx5_ib_dev *dev)
@@ -4917,6 +4955,10 @@ static int __init mlx5_ib_init(void)
{
int err;

+ mlx5_ib_event_wq = alloc_ordered_workqueue("mlx5_ib_event_wq", 0);
+ if (!mlx5_ib_event_wq)
+ return -ENOMEM;
+
mlx5_ib_odp_init();

err = mlx5_register_interface(&mlx5_ib_interface);
@@ -4927,6 +4969,7 @@ static int __init mlx5_ib_init(void)
static void __exit mlx5_ib_cleanup(void)
{
mlx5_unregister_interface(&mlx5_ib_interface);
+ destroy_workqueue(mlx5_ib_event_wq);
}

module_init(mlx5_ib_init);