net/mlx5e: Fix multicast counter not up-to-date in "ip -s"

Currently the FW does not generate events for counters other than error
counters. Unlike ".get_ethtool_stats", ".ndo_get_stats64" (which ip -s
uses) might run in atomic context, while the FW interface is non atomic.
Thus, 'ip' is not allowed to issue FW commands, so it will only display
cached counters in the driver.

Add a SW counter (mcast_packets) in the driver to count rx multicast
packets. The counter also counts broadcast packets, as we consider it a
special case of multicast.
Use the counter value when calling "ip -s"/"ifconfig".

Fixes: f62b8bb8f2 ("net/mlx5: Extend mlx5_core to support ConnectX-4 Ethernet functionality")
Signed-off-by: Ron Diskin <rondi@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Moshe Shemesh <moshe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

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

@@ -20,6 +20,11 @@ enum mlx5e_icosq_wqe_type {
 };
 
 /* General */
+static inline bool mlx5e_skb_is_multicast(struct sk_buff *skb)
+{
+	return skb->pkt_type == PACKET_MULTICAST || skb->pkt_type == PACKET_BROADCAST;
+}
+
 void mlx5e_trigger_irq(struct mlx5e_icosq *sq);
 void mlx5e_completion_event(struct mlx5_core_cq *mcq, struct mlx5_eqe *eqe);
 void mlx5e_cq_error_event(struct mlx5_core_cq *mcq, enum mlx5_event event);

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

@@ -3569,6 +3569,7 @@ void mlx5e_fold_sw_stats64(struct mlx5e_priv *priv, struct rtnl_link_stats64 *s)
 
 		s->rx_packets   += rq_stats->packets + xskrq_stats->packets;
 		s->rx_bytes     += rq_stats->bytes + xskrq_stats->bytes;
+		s->multicast    += rq_stats->mcast_packets + xskrq_stats->mcast_packets;
 
 		for (j = 0; j < priv->max_opened_tc; j++) {
 			struct mlx5e_sq_stats *sq_stats = &channel_stats->sq[j];
@@ -3584,7 +3585,6 @@ void
 mlx5e_get_stats(struct net_device *dev, struct rtnl_link_stats64 *stats)
 {
 	struct mlx5e_priv *priv = netdev_priv(dev);
-	struct mlx5e_vport_stats *vstats = &priv->stats.vport;
 	struct mlx5e_pport_stats *pstats = &priv->stats.pport;
 
 	/* In switchdev mode, monitor counters doesn't monitor
@@ -3619,12 +3619,6 @@ mlx5e_get_stats(struct net_device *dev, struct rtnl_link_stats64 *stats)
 	stats->rx_errors = stats->rx_length_errors + stats->rx_crc_errors +
 			   stats->rx_frame_errors;
 	stats->tx_errors = stats->tx_aborted_errors + stats->tx_carrier_errors;
-
-	/* vport multicast also counts packets that are dropped due to steering
-	 * or rx out of buffer
-	 */
-	stats->multicast =
-		VPORT_COUNTER_GET(vstats, received_eth_multicast.packets);
 }
 
 static void mlx5e_set_rx_mode(struct net_device *dev)

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

@@ -53,6 +53,7 @@
 #include "en/xsk/rx.h"
 #include "en/health.h"
 #include "en/params.h"
+#include "en/txrx.h"
 
 static struct sk_buff *
 mlx5e_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
@@ -1080,6 +1081,9 @@ static inline void mlx5e_build_rx_skb(struct mlx5_cqe64 *cqe,
 		mlx5e_enable_ecn(rq, skb);
 
 	skb->protocol = eth_type_trans(skb, netdev);
+
+	if (unlikely(mlx5e_skb_is_multicast(skb)))
+		stats->mcast_packets++;
 }
 
 static inline void mlx5e_complete_rx_cqe(struct mlx5e_rq *rq,

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

@@ -119,6 +119,7 @@ struct mlx5e_sw_stats {
 	u64 tx_nop;
 	u64 rx_lro_packets;
 	u64 rx_lro_bytes;
+	u64 rx_mcast_packets;
 	u64 rx_ecn_mark;
 	u64 rx_removed_vlan_packets;
 	u64 rx_csum_unnecessary;
@@ -298,6 +299,7 @@ struct mlx5e_rq_stats {
 	u64 csum_none;
 	u64 lro_packets;
 	u64 lro_bytes;
+	u64 mcast_packets;
 	u64 ecn_mark;
 	u64 removed_vlan_packets;
 	u64 xdp_drop;