Re: [PATCH] mlx5: Add ndo_poll_controller() implementation

[Saeed Mahameed]

On Fri, Sep 23, 2016 at 11:13 PM, Calvin Owens  wrote:
> This implements ndo_poll_controller in net_device_ops for mlx5, which is
> necessary to use netconsole with this driver.
>
> Signed-off-by: Calvin Owens 
> ---
>  drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 20 
>  1 file changed, 20 insertions(+)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c 
> b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> index 2459c7f..439476f 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> @@ -2786,6 +2786,20 @@ static void mlx5e_tx_timeout(struct net_device *dev)
> schedule_work(>tx_timeout_work);
>  }
>
> +#ifdef CONFIG_NET_POLL_CONTROLLER
> +/* Fake "interrupt" called by netpoll (eg netconsole) to send skbs without
> + * reenabling interrupts.
> + */
> +static void mlx5e_netpoll(struct net_device *dev)
> +{
> +   struct mlx5e_priv *priv = netdev_priv(dev);
> +   int i, nr_sq = priv->params.num_channels * priv->params.num_tc;
> +
> +   for (i = 0; i < nr_sq; i++)
> +   napi_schedule(priv->txq_to_sq_map[i]->cq.napi);

Hi Calvin,

Basically all CQs on the same channel are sharing the same napi, so
here you will end up calling napi_schedule more than once for each
napi (channel).
iterating over the SQs map is irrelevant here, all you need to do is
to iterate over the channels:

 for (i = 0; i < priv->params.num_channels; i++)
napi_schedule(priv->channel[i]->napi);


Thanks,
Saeed.

> +}
> +#endif
> +
>  static const struct net_device_ops mlx5e_netdev_ops_basic = {
> .ndo_open= mlx5e_open,
> .ndo_stop= mlx5e_close,
> @@ -2805,6 +2819,9 @@ static const struct net_device_ops 
> mlx5e_netdev_ops_basic = {
> .ndo_rx_flow_steer   = mlx5e_rx_flow_steer,
>  #endif
> .ndo_tx_timeout  = mlx5e_tx_timeout,
> +#ifdef CONFIG_NET_POLL_CONTROLLER
> +   .ndo_poll_controller = mlx5e_netpoll,
> +#endif
>  };
>
>  static const struct net_device_ops mlx5e_netdev_ops_sriov = {
> @@ -2836,6 +2853,9 @@ static const struct net_device_ops 
> mlx5e_netdev_ops_sriov = {
> .ndo_set_vf_link_state   = mlx5e_set_vf_link_state,
> .ndo_get_vf_stats= mlx5e_get_vf_stats,
> .ndo_tx_timeout  = mlx5e_tx_timeout,
> +#ifdef CONFIG_NET_POLL_CONTROLLER
> +   .ndo_poll_controller = mlx5e_netpoll,
> +#endif
>  };
>
>  static int mlx5e_check_required_hca_cap(struct mlx5_core_dev *mdev)
> --
> 2.9.3
>

[PATCH] mlx5: Add ndo_poll_controller() implementation

[Calvin Owens]

This implements ndo_poll_controller in net_device_ops for mlx5, which is
necessary to use netconsole with this driver.

Signed-off-by: Calvin Owens 
---
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 20 
 1 file changed, 20 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c 
b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 2459c7f..439476f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -2786,6 +2786,20 @@ static void mlx5e_tx_timeout(struct net_device *dev)
schedule_work(>tx_timeout_work);
 }
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+/* Fake "interrupt" called by netpoll (eg netconsole) to send skbs without
+ * reenabling interrupts.
+ */
+static void mlx5e_netpoll(struct net_device *dev)
+{
+   struct mlx5e_priv *priv = netdev_priv(dev);
+   int i, nr_sq = priv->params.num_channels * priv->params.num_tc;
+
+   for (i = 0; i < nr_sq; i++)
+   napi_schedule(priv->txq_to_sq_map[i]->cq.napi);
+}
+#endif
+
 static const struct net_device_ops mlx5e_netdev_ops_basic = {
.ndo_open= mlx5e_open,
.ndo_stop= mlx5e_close,
@@ -2805,6 +2819,9 @@ static const struct net_device_ops mlx5e_netdev_ops_basic 
= {
.ndo_rx_flow_steer   = mlx5e_rx_flow_steer,
 #endif
.ndo_tx_timeout  = mlx5e_tx_timeout,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+   .ndo_poll_controller = mlx5e_netpoll,
+#endif
 };
 
 static const struct net_device_ops mlx5e_netdev_ops_sriov = {
@@ -2836,6 +2853,9 @@ static const struct net_device_ops mlx5e_netdev_ops_sriov 
= {
.ndo_set_vf_link_state   = mlx5e_set_vf_link_state,
.ndo_get_vf_stats= mlx5e_get_vf_stats,
.ndo_tx_timeout  = mlx5e_tx_timeout,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+   .ndo_poll_controller = mlx5e_netpoll,
+#endif
 };
 
 static int mlx5e_check_required_hca_cap(struct mlx5_core_dev *mdev)
-- 
2.9.3