net/mlx5e: Use monitor counters for update stats

- Adding new notifier block (struct mlx5_nb) monitor_counters_nb
  for handeling MONITOR_COUNTER new event type.
- Adding work queue element: monitor_counters_work for re-arm and
  update stats.
- We re-queue the update stat work, only when working over firmware
  that doesn't support the monitored counters.
Signed-off-by: Eyal Davidovich <eyald@mellanox.com>
Reviewed-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/en.h

@@ -685,6 +685,8 @@ struct mlx5e_priv {
 	struct work_struct         set_rx_mode_work;
 	struct work_struct         tx_timeout_work;
 	struct work_struct         update_stats_work;
+	struct work_struct         monitor_counters_work;
+	struct mlx5_nb             monitor_counters_nb;
 
 	struct mlx5_core_dev      *mdev;
 	struct net_device         *netdev;
@@ -940,6 +942,7 @@ int mlx5e_create_tises(struct mlx5e_priv *priv);
 void mlx5e_cleanup_nic_tx(struct mlx5e_priv *priv);
 int mlx5e_close(struct net_device *netdev);
 int mlx5e_open(struct net_device *netdev);
+void mlx5e_update_ndo_stats(struct mlx5e_priv *priv);
 
 void mlx5e_queue_update_stats(struct mlx5e_priv *priv);
 int mlx5e_bits_invert(unsigned long a, int size);

drivers/net/ethernet/mellanox/mlx5/core/en/monitor_stats.c

@@ -3,6 +3,7 @@
 
 #include "en.h"
 #include "monitor_stats.h"
+#include "lib/eq.h"
 
 /* Driver will set the following watch counters list:
  * Ppcnt.802_3:
@@ -45,6 +46,39 @@ void mlx5e_monitor_counter_arm(struct mlx5e_priv *priv)
 	mlx5_cmd_exec(priv->mdev, in, sizeof(in), out, sizeof(out));
 }
 
+static void mlx5e_monitor_counters_work(struct work_struct *work)
+{
+	struct mlx5e_priv *priv = container_of(work, struct mlx5e_priv,
+					       monitor_counters_work);
+
+	mutex_lock(&priv->state_lock);
+	mlx5e_update_ndo_stats(priv);
+	mutex_unlock(&priv->state_lock);
+	mlx5e_monitor_counter_arm(priv);
+}
+
+static int mlx5e_monitor_event_handler(struct notifier_block *nb,
+				       unsigned long event, void *eqe)
+{
+	struct mlx5e_priv *priv = mlx5_nb_cof(nb, struct mlx5e_priv,
+					      monitor_counters_nb);
+	queue_work(priv->wq, &priv->monitor_counters_work);
+	return NOTIFY_OK;
+}
+
+void mlx5e_monitor_counter_start(struct mlx5e_priv *priv)
+{
+	MLX5_NB_INIT(&priv->monitor_counters_nb, mlx5e_monitor_event_handler,
+		     MONITOR_COUNTER);
+	mlx5_eq_notifier_register(priv->mdev, &priv->monitor_counters_nb);
+}
+
+static void mlx5e_monitor_counter_stop(struct mlx5e_priv *priv)
+{
+	mlx5_eq_notifier_unregister(priv->mdev, &priv->monitor_counters_nb);
+	cancel_work_sync(&priv->monitor_counters_work);
+}
+
 static int fill_monitor_counter_ppcnt_set1(int cnt, u32 *in)
 {
 	enum mlx5_monitor_counter_ppcnt ppcnt_cnt;
@@ -108,12 +142,14 @@ static void mlx5e_set_monitor_counter(struct mlx5e_priv *priv)
 /* check if mlx5e_monitor_counter_supported before calling this function*/
 void mlx5e_monitor_counter_init(struct mlx5e_priv *priv)
 {
+	INIT_WORK(&priv->monitor_counters_work, mlx5e_monitor_counters_work);
+	mlx5e_monitor_counter_start(priv);
 	mlx5e_set_monitor_counter(priv);
 	mlx5e_monitor_counter_arm(priv);
+	queue_work(priv->wq, &priv->update_stats_work);
 }
 
-/* check if mlx5e_monitor_counter_supported before calling this function*/
-void mlx5e_monitor_counter_cleanup(struct mlx5e_priv *priv)
+static void mlx5e_monitor_counter_disable(struct mlx5e_priv *priv)
 {
 	u32  in[MLX5_ST_SZ_DW(set_monitor_counter_in)]  = {};
 	u32 out[MLX5_ST_SZ_DW(set_monitor_counter_out)] = {};
@@ -124,3 +160,10 @@ void mlx5e_monitor_counter_cleanup(struct mlx5e_priv *priv)
 
 	mlx5_cmd_exec(priv->mdev, in, sizeof(in), out, sizeof(out));
 }
+
+/* check if mlx5e_monitor_counter_supported before calling this function*/
+void mlx5e_monitor_counter_cleanup(struct mlx5e_priv *priv)
+{
+	mlx5e_monitor_counter_disable(priv);
+	mlx5e_monitor_counter_stop(priv);
+}

drivers/net/ethernet/mellanox/mlx5/core/en_main.c

@@ -50,6 +50,7 @@
 #include "en/port.h"
 #include "en/xdp.h"
 #include "lib/eq.h"
+#include "en/monitor_stats.h"
 
 struct mlx5e_rq_param {
 	u32			rqc[MLX5_ST_SZ_DW(rqc)];
@@ -263,7 +264,7 @@ void mlx5e_update_stats(struct mlx5e_priv *priv)
 			mlx5e_stats_grps[i].update_stats(priv);
 }
 
-static void mlx5e_update_ndo_stats(struct mlx5e_priv *priv)
+void mlx5e_update_ndo_stats(struct mlx5e_priv *priv)
 {
 	int i;
 
@@ -3459,8 +3460,10 @@ mlx5e_get_stats(struct net_device *dev, struct rtnl_link_stats64 *stats)
 	struct mlx5e_vport_stats *vstats = &priv->stats.vport;
 	struct mlx5e_pport_stats *pstats = &priv->stats.pport;
 
-	/* update HW stats in background for next time */
-	mlx5e_queue_update_stats(priv);
+	if (!mlx5e_monitor_counter_supported(priv)) {
+		/* update HW stats in background for next time */
+		mlx5e_queue_update_stats(priv);
+	}
 
 	if (mlx5e_is_uplink_rep(priv)) {
 		stats->rx_packets = PPORT_802_3_GET(pstats, a_frames_received_ok);
@@ -4901,6 +4904,8 @@ static void mlx5e_nic_enable(struct mlx5e_priv *priv)
 	mlx5_lag_add(mdev, netdev);
 
 	mlx5e_enable_async_events(priv);
+	if (mlx5e_monitor_counter_supported(priv))
+		mlx5e_monitor_counter_init(priv);
 
 	if (MLX5_ESWITCH_MANAGER(priv->mdev))
 		mlx5e_register_vport_reps(priv);
@@ -4940,6 +4945,9 @@ static void mlx5e_nic_disable(struct mlx5e_priv *priv)
 	if (MLX5_ESWITCH_MANAGER(priv->mdev))
 		mlx5e_unregister_vport_reps(priv);
 
+	if (mlx5e_monitor_counter_supported(priv))
+		mlx5e_monitor_counter_cleanup(priv);
+
 	mlx5e_disable_async_events(priv);
 	mlx5_lag_remove(mdev);
 }