sfc: add XDP counters to ethtool stats

Count XDP packet drops, error drops, transmissions and redirects and
expose these counters via the ethtool stats command.

Signed-off-by: Charles McLachlan <cmclachlan@solarflare.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/sfc/ethtool.c

@@ -83,6 +83,10 @@ static const struct efx_sw_stat_desc efx_sw_stat_desc[] = {
 	EFX_ETHTOOL_UINT_CHANNEL_STAT(rx_frm_trunc),
 	EFX_ETHTOOL_UINT_CHANNEL_STAT(rx_merge_events),
 	EFX_ETHTOOL_UINT_CHANNEL_STAT(rx_merge_packets),
+	EFX_ETHTOOL_UINT_CHANNEL_STAT(rx_xdp_drops),
+	EFX_ETHTOOL_UINT_CHANNEL_STAT(rx_xdp_bad_drops),
+	EFX_ETHTOOL_UINT_CHANNEL_STAT(rx_xdp_tx),
+	EFX_ETHTOOL_UINT_CHANNEL_STAT(rx_xdp_redirect),
 };
 
 #define EFX_ETHTOOL_SW_STAT_COUNT ARRAY_SIZE(efx_sw_stat_desc)
@@ -399,6 +403,19 @@ static size_t efx_describe_per_queue_stats(struct efx_nic *efx, u8 *strings)
 			}
 		}
 	}
+	if (efx->xdp_tx_queue_count && efx->xdp_tx_queues) {
+		unsigned short xdp;
+
+		for (xdp = 0; xdp < efx->xdp_tx_queue_count; xdp++) {
+			n_stats++;
+			if (strings) {
+				snprintf(strings, ETH_GSTRING_LEN,
+					 "tx-xdp-cpu-%hu.tx_packets", xdp);
+				strings += ETH_GSTRING_LEN;
+			}
+		}
+	}
+
 	return n_stats;
 }
 
@@ -509,6 +526,14 @@ static void efx_ethtool_get_stats(struct net_device *net_dev,
 			data++;
 		}
 	}
+	if (efx->xdp_tx_queue_count && efx->xdp_tx_queues) {
+		int xdp;
+
+		for (xdp = 0; xdp < efx->xdp_tx_queue_count; xdp++) {
+			data[0] = efx->xdp_tx_queues[xdp]->tx_packets;
+			data++;
+		}
+	}
 
 	efx_ptp_update_stats(efx, data);
 }

drivers/net/ethernet/sfc/net_driver.h

@@ -453,6 +453,10 @@ enum efx_sync_events_state {
  *	lack of descriptors
  * @n_rx_merge_events: Number of RX merged completion events
  * @n_rx_merge_packets: Number of RX packets completed by merged events
+ * @n_rx_xdp_drops: Count of RX packets intentionally dropped due to XDP
+ * @n_rx_xdp_bad_drops: Count of RX packets dropped due to XDP errors
+ * @n_rx_xdp_tx: Count of RX packets retransmitted due to XDP
+ * @n_rx_xdp_redirect: Count of RX packets redirected to a different NIC by XDP
  * @rx_pkt_n_frags: Number of fragments in next packet to be delivered by
  *	__efx_rx_packet(), or zero if there is none
  * @rx_pkt_index: Ring index of first buffer for next packet to be delivered
@@ -506,6 +510,10 @@ struct efx_channel {
 	unsigned int n_rx_nodesc_trunc;
 	unsigned int n_rx_merge_events;
 	unsigned int n_rx_merge_packets;
+	unsigned int n_rx_xdp_drops;
+	unsigned int n_rx_xdp_bad_drops;
+	unsigned int n_rx_xdp_tx;
+	unsigned int n_rx_xdp_redirect;
 
 	unsigned int rx_pkt_n_frags;
 	unsigned int rx_pkt_index;

drivers/net/ethernet/sfc/rx.c

@@ -677,6 +677,7 @@ static bool efx_do_xdp(struct efx_nic *efx, struct efx_channel *channel,
 			netif_err(efx, rx_err, efx->net_dev,
 				  "XDP is not possible with multiple receive fragments (%d)\n",
 				  channel->rx_pkt_n_frags);
+		channel->n_rx_xdp_bad_drops++;
 		return false;
 	}
 
@@ -722,6 +723,9 @@ static bool efx_do_xdp(struct efx_nic *efx, struct efx_channel *channel,
 			if (net_ratelimit())
 				netif_err(efx, rx_err, efx->net_dev,
 					  "XDP TX failed (%d)\n", err);
+			channel->n_rx_xdp_bad_drops++;
+		} else {
+			channel->n_rx_xdp_tx++;
 		}
 		break;
 
@@ -732,12 +736,16 @@ static bool efx_do_xdp(struct efx_nic *efx, struct efx_channel *channel,
 			if (net_ratelimit())
 				netif_err(efx, rx_err, efx->net_dev,
 					  "XDP redirect failed (%d)\n", err);
+			channel->n_rx_xdp_bad_drops++;
+		} else {
+			channel->n_rx_xdp_redirect++;
 		}
 		break;
 
 	default:
 		bpf_warn_invalid_xdp_action(xdp_act);
 		efx_free_rx_buffers(rx_queue, rx_buf, 1);
+		channel->n_rx_xdp_bad_drops++;
 		break;
 
 	case XDP_ABORTED:
@@ -745,6 +753,7 @@ static bool efx_do_xdp(struct efx_nic *efx, struct efx_channel *channel,
 		/* Fall through */
 	case XDP_DROP:
 		efx_free_rx_buffers(rx_queue, rx_buf, 1);
+		channel->n_rx_xdp_drops++;
 		break;
 	}