[PATCH net-next v5] ixgbe: implement get_queue_stats_rx

Hook into the netdev_stat_ops interface to expose per RX queue
statistics through the netdev generic netlink API.

The following counters are filled:
 - bytes: maps directly to bytes
 - packets: maps directly to packets
 - alloc_fail: sum of alloc_rx_page_failed and alloc_rx_buff_failed
 - csum_bad: maps directly to csum_err, which is incremented for both
   IP header and L4 checksum errors in ixgbe_rx_checksum().

The new per-queue stats can be observed with:
  $ ynltool qstats show scope queue

Signed-off-by: Kshitiz Bartariya <[email protected]>
---
v5:
 - Added READ_ONCE() and NULL check for accessing adapter->rx_ring[i]
 - Added u64_stats_fetch_begin before reading stats from rx_ring
 Suggested by Simon Horman

v4:
 - Changed comment format from // to /* */
 - Moved ixgbe_stat_ops declaration next to the ixgbe_netdev_ops
 Suggested by Jedrzej Jagielski.
https://lore.kernel.org/lkml/[email protected]/

v3:
 - Added bytes and packets stats counters
 - Implemented ixgbe_get_base_stats function
 As suggested by AI on 
 https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260603174857.78666-1-kshitiz.bartariya%40zohomail.in
 https://lore.kernel.org/lkml/[email protected]/

v2:
 Amended commit message with command to get RX queue stats as 
 suggested by Jedrzej Jagielski.
 https://lore.kernel.org/lkml/[email protected]/

v1: 
 https://lore.kernel.org/lkml/[email protected]/

 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 45 +++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 8873a8cc4a18..560177f135ff 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -9760,6 +9760,45 @@ static void ixgbe_get_stats64(struct net_device *netdev,
 	stats->rx_missed_errors	= netdev->stats.rx_missed_errors;
 }
 
+static void ixgbe_get_queue_stats_rx(struct net_device *dev, int idx,
+				     struct netdev_queue_stats_rx *stats)
+{
+	struct ixgbe_adapter *adapter = ixgbe_from_netdev(dev);
+	struct ixgbe_ring *ring = READ_ONCE(adapter->rx_ring[idx]);
+	u64 bytes, packets, alloc_rx_page_failed, alloc_rx_buff_failed,
+		csum_err;
+	unsigned int start;
+
+	if (ring) {
+		do {
+			start = u64_stats_fetch_begin(&ring->syncp);
+			bytes = ring->stats.bytes;
+			packets = ring->stats.packets;
+			alloc_rx_page_failed =
+				ring->rx_stats.alloc_rx_page_failed;
+			alloc_rx_buff_failed =
+				ring->rx_stats.alloc_rx_buff_failed;
+			csum_err = ring->rx_stats.csum_err;
+		} while (u64_stats_fetch_retry(&ring->syncp, start));
+	}
+
+	stats->bytes = bytes;
+	stats->packets = packets;
+	stats->alloc_fail = alloc_rx_page_failed + alloc_rx_buff_failed;
+	stats->csum_bad = csum_err;
+}
+
+static void ixgbe_get_base_stats(struct net_device *dev,
+				 struct netdev_queue_stats_rx *rx,
+				 struct netdev_queue_stats_tx *tx)
+{
+	/* ixgbe has no inactive queues */
+	rx->bytes = 0;
+	rx->packets = 0;
+	rx->alloc_fail = 0;
+	rx->csum_bad = 0;
+}
+
 static int ixgbe_ndo_get_vf_stats(struct net_device *netdev, int vf,
 				  struct ifla_vf_stats *vf_stats)
 {
@@ -11117,6 +11156,11 @@ static const struct net_device_ops ixgbe_netdev_ops = {
 	.ndo_hwtstamp_set	= ixgbe_ptp_hwtstamp_set,
 };
 
+static const struct netdev_stat_ops ixgbe_stat_ops = {
+	.get_queue_stats_rx = ixgbe_get_queue_stats_rx,
+	.get_base_stats = ixgbe_get_base_stats,
+};
+
 static void ixgbe_disable_txr_hw(struct ixgbe_adapter *adapter,
 				 struct ixgbe_ring *tx_ring)
 {
@@ -11663,6 +11707,7 @@ static int ixgbe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	hw->phy.mdio.mdio_write = ixgbe_mdio_write;
 
 	netdev->netdev_ops = &ixgbe_netdev_ops;
+	netdev->stat_ops = &ixgbe_stat_ops;
 	ixgbe_set_ethtool_ops(netdev);
 	netdev->watchdog_timeo = 5 * HZ;
 	strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name));
-- 
2.50.1 (Apple Git-155)