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 8990f468a (net: rx_dropped
accounting), thus reverting it.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index f6fbcc0..f54251e 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -225,16 +225,15 @@
}
}
- 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 @@
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;
}