Commit 93ab4881 authored by Yeounsu Moon's avatar Yeounsu Moon Committed by Jakub Kicinski
Browse files

net: natsemi: fix `rx_dropped` double accounting on `netif_rx()` failure 



`netif_rx()` already increments `rx_dropped` core stat when it fails.
The driver was also updating `ndev->stats.rx_dropped` in the same path.
Since both are reported together via `ip -s -s` command, this resulted
in drops being counted twice in user-visible stats.

Keep the driver update on `if (unlikely(!skb))`, but skip it after
`netif_rx()` errors.

Fixes: caf586e5 ("net: add a core netdev->rx_dropped counter")
Signed-off-by: default avatarYeounsu Moon <yyyynoom@gmail.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250913060135.35282-3-yyyynoom@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 97499e28

drivers/net/ethernet/natsemi/ns83820.c

+6 −7
Original line number Diff line number Diff line
@@ -820,7 +820,7 @@ static void rx_irq(struct net_device *ndev) 
	struct ns83820 *dev = PRIV(ndev);

	struct rx_info *info = &dev->rx_info;

	unsigned next_rx;

	int rx_rc, len;

	int len;

	u32 cmdsts;

	__le32 *desc;

	unsigned long flags;
@@ -881,8 +881,10 @@ static void rx_irq(struct net_device *ndev) 
		if (likely(CMDSTS_OK & cmdsts)) {

#endif

			skb_put(skb, len);

			if (unlikely(!skb))

			if (unlikely(!skb)) {

				ndev->stats.rx_dropped++;

				goto netdev_mangle_me_harder_failed;

			}

			if (cmdsts & CMDSTS_DEST_MULTI)

				ndev->stats.multicast++;

			ndev->stats.rx_packets++;
@@ -901,15 +903,12 @@ static void rx_irq(struct net_device *ndev) 
				__vlan_hwaccel_put_tag(skb, htons(ETH_P_IPV6), tag);

			}

#endif

			rx_rc = netif_rx(skb);

			if (NET_RX_DROP == rx_rc) {

netdev_mangle_me_harder_failed:

				ndev->stats.rx_dropped++;

			}

			netif_rx(skb);

		} else {

			dev_kfree_skb_irq(skb);

		}



netdev_mangle_me_harder_failed:

		nr++;

		next_rx = info->next_rx;

		desc = info->descs + (DESC_SIZE * next_rx);