[PATCH net-next V4 9/9] eth: fbnic: Report XDP stats via ethtool

[Mohsin Bashir <mohsin.bashr@gmail.com>]

Add support to collect XDP stats via ethtool API. We record
packets and bytes sent, and packets dropped on the XDP_TX path.

ethtool -S eth0 | grep xdp | grep -v "0"
     xdp_tx_queue_13_packets: 2
     xdp_tx_queue_13_bytes: 16126

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Mohsin Bashir <mohsin.bashr@gmail.com>
---
 .../net/ethernet/meta/fbnic/fbnic_ethtool.c   | 50 ++++++++++++++++++-
 1 file changed, 49 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c b/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c
index 742b557d0e56..ceb8f88ae41c 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c
@@ -112,6 +112,20 @@ static const struct fbnic_stat fbnic_gstrings_hw_q_stats[] = {
 	 FBNIC_HW_RXB_DEQUEUE_STATS_LEN * FBNIC_RXB_DEQUEUE_INDICES + \
 	 FBNIC_HW_Q_STATS_LEN * FBNIC_MAX_QUEUES)
 
+#define FBNIC_QUEUE_STAT(name, stat) \
+	FBNIC_STAT_FIELDS(fbnic_ring, name, stat)
+
+static const struct fbnic_stat fbnic_gstrings_xdp_stats[] = {
+	FBNIC_QUEUE_STAT("xdp_tx_queue_%u_packets", stats.packets),
+	FBNIC_QUEUE_STAT("xdp_tx_queue_%u_bytes", stats.bytes),
+	FBNIC_QUEUE_STAT("xdp_tx_queue_%u_dropped", stats.dropped),
+};
+
+#define FBNIC_XDP_STATS_LEN ARRAY_SIZE(fbnic_gstrings_xdp_stats)
+
+#define FBNIC_STATS_LEN \
+	(FBNIC_HW_STATS_LEN + FBNIC_XDP_STATS_LEN * FBNIC_MAX_XDPQS)
+
 static void
 fbnic_get_drvinfo(struct net_device *netdev, struct ethtool_drvinfo *drvinfo)
 {
@@ -422,6 +436,16 @@ static void fbnic_get_rxb_dequeue_strings(u8 **data, unsigned int idx)
 		ethtool_sprintf(data, stat->string, idx);
 }
 
+static void fbnic_get_xdp_queue_strings(u8 **data, unsigned int idx)
+{
+	const struct fbnic_stat *stat;
+	int i;
+
+	stat = fbnic_gstrings_xdp_stats;
+	for (i = 0; i < FBNIC_XDP_STATS_LEN; i++, stat++)
+		ethtool_sprintf(data, stat->string, idx);
+}
+
 static void fbnic_get_strings(struct net_device *dev, u32 sset, u8 *data)
 {
 	const struct fbnic_stat *stat;
@@ -447,6 +471,9 @@ static void fbnic_get_strings(struct net_device *dev, u32 sset, u8 *data)
 			for (i = 0; i < FBNIC_HW_Q_STATS_LEN; i++, stat++)
 				ethtool_sprintf(&data, stat->string, idx);
 		}
+
+		for (i = 0; i < FBNIC_MAX_XDPQS; i++)
+			fbnic_get_xdp_queue_strings(&data, i);
 		break;
 	}
 }
@@ -464,6 +491,24 @@ static void fbnic_report_hw_stats(const struct fbnic_stat *stat,
 	}
 }
 
+static void fbnic_get_xdp_queue_stats(struct fbnic_ring *ring, u64 **data)
+{
+	const struct fbnic_stat *stat;
+	int i;
+
+	if (!ring) {
+		*data += FBNIC_XDP_STATS_LEN;
+		return;
+	}
+
+	stat = fbnic_gstrings_xdp_stats;
+	for (i = 0; i < FBNIC_XDP_STATS_LEN; i++, stat++, (*data)++) {
+		u8 *p = (u8 *)ring + stat->offset;
+
+		**data = *(u64 *)p;
+	}
+}
+
 static void fbnic_get_ethtool_stats(struct net_device *dev,
 				    struct ethtool_stats *stats, u64 *data)
 {
@@ -511,13 +556,16 @@ static void fbnic_get_ethtool_stats(struct net_device *dev,
 				      FBNIC_HW_Q_STATS_LEN, &data);
 	}
 	spin_unlock(&fbd->hw_stats_lock);
+
+	for (i = 0; i < FBNIC_MAX_XDPQS; i++)
+		fbnic_get_xdp_queue_stats(fbn->tx[i + FBNIC_MAX_TXQS], &data);
 }
 
 static int fbnic_get_sset_count(struct net_device *dev, int sset)
 {
 	switch (sset) {
 	case ETH_SS_STATS:
-		return FBNIC_HW_STATS_LEN;
+		return FBNIC_STATS_LEN;
 	default:
 		return -EOPNOTSUPP;
 	}
-- 
2.47.3