net: ena: add support for reporting of packet drops

1. Add support for getting tx drops from the device and saving them
in the driver.
2. Report tx via netdev stats.

Signed-off-by: Igor Chauskin <igorch@amazon.com>
Signed-off-by: Guy Tzalik <gtzalik@amazon.com>
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/amazon/ena/ena_admin_defs.h

@@ -404,6 +404,10 @@ struct ena_admin_basic_stats {
 	u32 rx_drops_low;
 
 	u32 rx_drops_high;
+
+	u32 tx_drops_low;
+
+	u32 tx_drops_high;
 };
 
 struct ena_admin_acq_get_stats_resp {
@@ -1017,6 +1021,10 @@ struct ena_admin_aenq_keep_alive_desc {
 	u32 rx_drops_low;
 
 	u32 rx_drops_high;
+
+	u32 tx_drops_low;
+
+	u32 tx_drops_high;
 };
 
 struct ena_admin_ena_mmio_req_read_less_resp {

drivers/net/ethernet/amazon/ena/ena_netdev.c

@@ -3172,6 +3172,7 @@ static void ena_get_stats64(struct net_device *netdev,
 	struct ena_ring *rx_ring, *tx_ring;
 	unsigned int start;
 	u64 rx_drops;
+	u64 tx_drops;
 	int i;
 
 	if (!test_bit(ENA_FLAG_DEV_UP, &adapter->flags))
@@ -3206,9 +3207,11 @@ static void ena_get_stats64(struct net_device *netdev,
 	do {
 		start = u64_stats_fetch_begin_irq(&adapter->syncp);
 		rx_drops = adapter->dev_stats.rx_drops;
+		tx_drops = adapter->dev_stats.tx_drops;
 	} while (u64_stats_fetch_retry_irq(&adapter->syncp, start));
 
 	stats->rx_dropped = rx_drops;
+	stats->tx_dropped = tx_drops;
 
 	stats->multicast = 0;
 	stats->collisions = 0;
@@ -4517,14 +4520,17 @@ static void ena_keep_alive_wd(void *adapter_data,
 	struct ena_adapter *adapter = (struct ena_adapter *)adapter_data;
 	struct ena_admin_aenq_keep_alive_desc *desc;
 	u64 rx_drops;
+	u64 tx_drops;
 
 	desc = (struct ena_admin_aenq_keep_alive_desc *)aenq_e;
 	adapter->last_keep_alive_jiffies = jiffies;
 
 	rx_drops = ((u64)desc->rx_drops_high << 32) | desc->rx_drops_low;
+	tx_drops = ((u64)desc->tx_drops_high << 32) | desc->tx_drops_low;
 
 	u64_stats_update_begin(&adapter->syncp);
 	adapter->dev_stats.rx_drops = rx_drops;
+	adapter->dev_stats.tx_drops = tx_drops;
 	u64_stats_update_end(&adapter->syncp);
 }
 

drivers/net/ethernet/amazon/ena/ena_netdev.h

@@ -334,6 +334,7 @@ struct ena_stats_dev {
 	u64 interface_down;
 	u64 admin_q_pause;
 	u64 rx_drops;
+	u64 tx_drops;
 };
 
 enum ena_flags_t {