Commit caf586e5 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: add a core netdev->rx_dropped counter 



In various situations, a device provides a packet to our stack and we
drop it before it enters protocol stack :
- softnet backlog full (accounted in /proc/net/softnet_stat)
- bad vlan tag (not accounted)
- unknown/unregistered protocol (not accounted)

We can handle a per-device counter of such dropped frames at core level,
and automatically adds it to the device provided stats (rx_dropped), so
that standard tools can be used (ifconfig, ip link, cat /proc/net/dev)

This is a generalization of commit 8990f468 (net: rx_dropped
accounting), thus reverting it.

Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a00eac0c

drivers/net/loopback.c

+1 −7
Original line number Diff line number Diff line
@@ -64,7 +64,6 @@ struct pcpu_lstats { 
	u64			packets;

	u64			bytes;

	struct u64_stats_sync	syncp;

	unsigned long		drops;

};



/*
@@ -90,8 +89,7 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb, 
		lb_stats->bytes += len;

		lb_stats->packets++;

		u64_stats_update_end(&lb_stats->syncp);

	} else

		lb_stats->drops++;

	}



	return NETDEV_TX_OK;

}
@@ -101,7 +99,6 @@ static struct rtnl_link_stats64 *loopback_get_stats64(struct net_device *dev, 
{

	u64 bytes = 0;

	u64 packets = 0;

	u64 drops = 0;

	int i;



	for_each_possible_cpu(i) {
@@ -115,14 +112,11 @@ static struct rtnl_link_stats64 *loopback_get_stats64(struct net_device *dev, 
			tbytes = lb_stats->bytes;

			tpackets = lb_stats->packets;

		} while (u64_stats_fetch_retry(&lb_stats->syncp, start));

		drops   += lb_stats->drops;

		bytes   += tbytes;

		packets += tpackets;

	}

	stats->rx_packets = packets;

	stats->tx_packets = packets;

	stats->rx_dropped = drops;

	stats->rx_errors  = drops;

	stats->rx_bytes   = bytes;

	stats->tx_bytes   = bytes;

	return stats;

include/linux/netdevice.h

+3 −0
Original line number Diff line number Diff line
@@ -884,6 +884,9 @@ struct net_device { 
	int			iflink;



	struct net_device_stats	stats;

	atomic_long_t		rx_dropped; /* dropped packets by core network

					     * Do not use this in drivers.

					     */



#ifdef CONFIG_WIRELESS_EXT

	/* List of functions to handle Wireless Extensions (instead of ioctl).

net/8021q/vlan.h

+0 −2
Original line number Diff line number Diff line
@@ -25,7 +25,6 @@ struct vlan_priority_tci_mapping { 
 *	@rx_multicast: number of received multicast packets

 *	@syncp: synchronization point for 64bit counters

 *	@rx_errors: number of errors

 *	@rx_dropped: number of dropped packets

 */

struct vlan_rx_stats {

	u64			rx_packets;
@@ -33,7 +32,6 @@ struct vlan_rx_stats { 
	u64			rx_multicast;

	struct u64_stats_sync	syncp;

	unsigned long		rx_errors;

	unsigned long		rx_dropped;

};



/**

net/8021q/vlan_core.c

+2 −0
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp, 
	return polling ? netif_receive_skb(skb) : netif_rx(skb);



drop:

	atomic_long_inc(&skb->dev->rx_dropped);

	dev_kfree_skb_any(skb);

	return NET_RX_DROP;

}
@@ -123,6 +124,7 @@ vlan_gro_common(struct napi_struct *napi, struct vlan_group *grp, 
	return dev_gro_receive(napi, skb);



drop:

	atomic_long_inc(&skb->dev->rx_dropped);

	return GRO_DROP;

}

net/8021q/vlan_dev.c

+4 −7
Original line number Diff line number Diff line
@@ -225,16 +225,15 @@ int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev, 
		}

	}



	if (unlikely(netif_rx(skb) == NET_RX_DROP)) {

		if (rx_stats)

			rx_stats->rx_dropped++;

	}

	netif_rx(skb);



	rcu_read_unlock();

	return NET_RX_SUCCESS;



err_unlock:

	rcu_read_unlock();

err_free:

	atomic_long_inc(&dev->rx_dropped);

	kfree_skb(skb);

	return NET_RX_DROP;

}
@@ -846,15 +845,13 @@ static struct rtnl_link_stats64 *vlan_dev_get_stats64(struct net_device *dev, st 
			accum.rx_packets += rxpackets;

			accum.rx_bytes   += rxbytes;

			accum.rx_multicast += rxmulticast;

			/* rx_errors, rx_dropped are ulong, not protected by syncp */

			/* rx_errors is ulong, not protected by syncp */

			accum.rx_errors  += p->rx_errors;

			accum.rx_dropped += p->rx_dropped;

		}

		stats->rx_packets = accum.rx_packets;

		stats->rx_bytes   = accum.rx_bytes;

		stats->rx_errors  = accum.rx_errors;

		stats->multicast  = accum.rx_multicast;

		stats->rx_dropped = accum.rx_dropped;

	}

	return stats;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE