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>

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>
Eric Dumazet · David S. Miller
1 parent a00eac0c45
Showing 11 changed files with 26 additions and 34 deletions Side-by-side Diff
drivers/net/loopback.c
include/linux/netdevice.h
net/8021q/vlan.h
net/8021q/vlan_core.c
net/8021q/vlan_dev.c
net/core/dev.c
net/ipv4/ip_gre.c
net/ipv4/ipip.c
net/ipv6/ip6_tunnel.c
net/ipv6/ip6mr.c
net/ipv6/sit.c
@@ -64,7 +64,6 @@
 	u64			packets;
 	u64			bytes;
 	struct u64_stats_sync	syncp;
-	unsigned long		drops;
 };
  
 /*
@@ -90,8 +89,7 @@
 		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 @@
 {
 	u64 bytes = 0;
 	u64 packets = 0;
-	u64 drops = 0;
 	int i;
  
 	for_each_possible_cpu(i) {
  
@@ -115,14 +112,11 @@
 			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;
@@ -884,6 +884,9 @@
 	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).
@@ -25,7 +25,6 @@
  *	@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 @@
 	u64			rx_multicast;
 	struct u64_stats_sync	syncp;
 	unsigned long		rx_errors;
-	unsigned long		rx_dropped;
 };
  
 /**
@@ -33,6 +33,7 @@
 	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 @@
 	return dev_gro_receive(napi, skb);
  
 drop:
+	atomic_long_inc(&skb->dev->rx_dropped);
 	return GRO_DROP;
 }
  
@@ -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;
 }
@@ -1483,8 +1483,9 @@
 	skb_orphan(skb);
 	nf_reset(skb);
  
-	if (!(dev->flags & IFF_UP) ||
-	    (skb->len > (dev->mtu + dev->hard_header_len))) {
+	if (unlikely(!(dev->flags & IFF_UP) ||
+		     (skb->len > (dev->mtu + dev->hard_header_len)))) {
+		atomic_long_inc(&dev->rx_dropped);
 		kfree_skb(skb);
 		return NET_RX_DROP;
 	}
@@ -2548,6 +2549,7 @@
  
 	local_irq_restore(flags);
  
+	atomic_long_inc(&skb->dev->rx_dropped);
 	kfree_skb(skb);
 	return NET_RX_DROP;
 }
@@ -2995,6 +2997,7 @@
 	if (pt_prev) {
 		ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
 	} else {
+		atomic_long_inc(&skb->dev->rx_dropped);
 		kfree_skb(skb);
 		/* Jamal, now you will not able to escape explaining
 		 * me how you were going to use this. :-)
  
  
@@ -5429,14 +5432,14 @@
  
 	if (ops->ndo_get_stats64) {
 		memset(storage, 0, sizeof(*storage));
-		return ops->ndo_get_stats64(dev, storage);
-	}
-	if (ops->ndo_get_stats) {
+		ops->ndo_get_stats64(dev, storage);
+	} else if (ops->ndo_get_stats) {
 		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
-		return storage;
+	} else {
+		netdev_stats_to_stats64(storage, &dev->stats);
+		dev_txq_stats_fold(dev, storage);
 	}
-	netdev_stats_to_stats64(storage, &dev->stats);
-	dev_txq_stats_fold(dev, storage);
+	storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
 	return storage;
 }
 EXPORT_SYMBOL(dev_get_stats);
@@ -679,8 +679,7 @@
 		skb_reset_network_header(skb);
 		ipgre_ecn_decapsulate(iph, skb);
  
-		if (netif_rx(skb) == NET_RX_DROP)
-			tunnel->dev->stats.rx_dropped++;
+		netif_rx(skb);
  
 		rcu_read_unlock();
 		return 0;
@@ -414,8 +414,7 @@
  
 		ipip_ecn_decapsulate(iph, skb);
  
-		if (netif_rx(skb) == NET_RX_DROP)
-			tunnel->dev->stats.rx_dropped++;
+		netif_rx(skb);
  
 		rcu_read_unlock();
 		return 0;
@@ -768,8 +768,7 @@
  
 		dscp_ecn_decapsulate(t, ipv6h, skb);
  
-		if (netif_rx(skb) == NET_RX_DROP)
-			t->dev->stats.rx_dropped++;
+		netif_rx(skb);
  
 		rcu_read_unlock();
 		return 0;
@@ -666,8 +666,7 @@
  
 	skb_tunnel_rx(skb, reg_dev);
  
-	if (netif_rx(skb) == NET_RX_DROP)
-		reg_dev->stats.rx_dropped++;
+	netif_rx(skb);
  
 	dev_put(reg_dev);
 	return 0;
@@ -600,8 +600,7 @@
  
 		ipip6_ecn_decapsulate(iph, skb);
  
-		if (netif_rx(skb) == NET_RX_DROP)
-			tunnel->dev->stats.rx_dropped++;
+		netif_rx(skb);
  
 		rcu_read_unlock();
 		return 0;
...	...	@@ -64,7 +64,6 @@
64	64	u64 packets;
65	65	u64 bytes;
66	66	struct u64_stats_sync syncp;
67		- unsigned long drops;
68	67	};
69	68
70	69	/*
...	...	@@ -90,8 +89,7 @@
90	89	lb_stats->bytes += len;
91	90	lb_stats->packets++;
92	91	u64_stats_update_end(&lb_stats->syncp);
93		- } else
94		- lb_stats->drops++;
	92	+ }
95	93
96	94	return NETDEV_TX_OK;
97	95	}
...	...	@@ -101,7 +99,6 @@
101	99	{
102	100	u64 bytes = 0;
103	101	u64 packets = 0;
104		- u64 drops = 0;
105	102	int i;
106	103
107	104	for_each_possible_cpu(i) {
108	105
...	...	@@ -115,14 +112,11 @@
115	112	tbytes = lb_stats->bytes;
116	113	tpackets = lb_stats->packets;
117	114	} while (u64_stats_fetch_retry(&lb_stats->syncp, start));
118		- drops += lb_stats->drops;
119	115	bytes += tbytes;
120	116	packets += tpackets;
121	117	}
122	118	stats->rx_packets = packets;
123	119	stats->tx_packets = packets;
124		- stats->rx_dropped = drops;
125		- stats->rx_errors = drops;
126	120	stats->rx_bytes = bytes;
127	121	stats->tx_bytes = bytes;
128	122	return stats;
...	...	@@ -884,6 +884,9 @@
884	884	int iflink;
885	885
886	886	struct net_device_stats stats;
	887	+ atomic_long_t rx_dropped; /* dropped packets by core network
	888	+ * Do not use this in drivers.
	889	+ */
887	890
888	891	#ifdef CONFIG_WIRELESS_EXT
889	892	/* List of functions to handle Wireless Extensions (instead of ioctl).
...	...	@@ -25,7 +25,6 @@
25	25	* @rx_multicast: number of received multicast packets
26	26	* @syncp: synchronization point for 64bit counters
27	27	* @rx_errors: number of errors
28		- * @rx_dropped: number of dropped packets
29	28	*/
30	29	struct vlan_rx_stats {
31	30	u64 rx_packets;
...	...	@@ -33,7 +32,6 @@
33	32	u64 rx_multicast;
34	33	struct u64_stats_sync syncp;
35	34	unsigned long rx_errors;
36		- unsigned long rx_dropped;
37	35	};
38	36
39	37	/**
...	...	@@ -33,6 +33,7 @@
33	33	return polling ? netif_receive_skb(skb) : netif_rx(skb);
34	34
35	35	drop:
	36	+ atomic_long_inc(&skb->dev->rx_dropped);
36	37	dev_kfree_skb_any(skb);
37	38	return NET_RX_DROP;
38	39	}
...	...	@@ -123,6 +124,7 @@
123	124	return dev_gro_receive(napi, skb);
124	125
125	126	drop:
	127	+ atomic_long_inc(&skb->dev->rx_dropped);
126	128	return GRO_DROP;
127	129	}
128	130
...	...	@@ -225,16 +225,15 @@
225	225	}
226	226	}
227	227
228		- if (unlikely(netif_rx(skb) == NET_RX_DROP)) {
229		- if (rx_stats)
230		- rx_stats->rx_dropped++;
231		- }
	228	+ netif_rx(skb);
	229	+
232	230	rcu_read_unlock();
233	231	return NET_RX_SUCCESS;
234	232
235	233	err_unlock:
236	234	rcu_read_unlock();
237	235	err_free:
	236	+ atomic_long_inc(&dev->rx_dropped);
238	237	kfree_skb(skb);
239	238	return NET_RX_DROP;
240	239	}
241	240
242	241
...	...	@@ -846,15 +845,13 @@
846	845	accum.rx_packets += rxpackets;
847	846	accum.rx_bytes += rxbytes;
848	847	accum.rx_multicast += rxmulticast;
849		- /* rx_errors, rx_dropped are ulong, not protected by syncp */
	848	+ /* rx_errors is ulong, not protected by syncp */
850	849	accum.rx_errors += p->rx_errors;
851		- accum.rx_dropped += p->rx_dropped;
852	850	}
853	851	stats->rx_packets = accum.rx_packets;
854	852	stats->rx_bytes = accum.rx_bytes;
855	853	stats->rx_errors = accum.rx_errors;
856	854	stats->multicast = accum.rx_multicast;
857		- stats->rx_dropped = accum.rx_dropped;
858	855	}
859	856	return stats;
860	857	}
...	...	@@ -1483,8 +1483,9 @@
1483	1483	skb_orphan(skb);
1484	1484	nf_reset(skb);
1485	1485
1486		- if (!(dev->flags & IFF_UP) \|\|
1487		- (skb->len > (dev->mtu + dev->hard_header_len))) {
	1486	+ if (unlikely(!(dev->flags & IFF_UP) \|\|
	1487	+ (skb->len > (dev->mtu + dev->hard_header_len)))) {
	1488	+ atomic_long_inc(&dev->rx_dropped);
1488	1489	kfree_skb(skb);
1489	1490	return NET_RX_DROP;
1490	1491	}
...	...	@@ -2548,6 +2549,7 @@
2548	2549
2549	2550	local_irq_restore(flags);
2550	2551
	2552	+ atomic_long_inc(&skb->dev->rx_dropped);
2551	2553	kfree_skb(skb);
2552	2554	return NET_RX_DROP;
2553	2555	}
...	...	@@ -2995,6 +2997,7 @@
2995	2997	if (pt_prev) {
2996	2998	ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
2997	2999	} else {
	3000	+ atomic_long_inc(&skb->dev->rx_dropped);
2998	3001	kfree_skb(skb);
2999	3002	/* Jamal, now you will not able to escape explaining
3000	3003	* me how you were going to use this. :-)
3001	3004
3002	3005
...	...	@@ -5429,14 +5432,14 @@
5429	5432
5430	5433	if (ops->ndo_get_stats64) {
5431	5434	memset(storage, 0, sizeof(*storage));
5432		- return ops->ndo_get_stats64(dev, storage);
5433		- }
5434		- if (ops->ndo_get_stats) {
	5435	+ ops->ndo_get_stats64(dev, storage);
	5436	+ } else if (ops->ndo_get_stats) {
5435	5437	netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
5436		- return storage;
	5438	+ } else {
	5439	+ netdev_stats_to_stats64(storage, &dev->stats);
	5440	+ dev_txq_stats_fold(dev, storage);
5437	5441	}
5438		- netdev_stats_to_stats64(storage, &dev->stats);
5439		- dev_txq_stats_fold(dev, storage);
	5442	+ storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
5440	5443	return storage;
5441	5444	}
5442	5445	EXPORT_SYMBOL(dev_get_stats);
...	...	@@ -679,8 +679,7 @@
679	679	skb_reset_network_header(skb);
680	680	ipgre_ecn_decapsulate(iph, skb);
681	681
682		- if (netif_rx(skb) == NET_RX_DROP)
683		- tunnel->dev->stats.rx_dropped++;
	682	+ netif_rx(skb);
684	683
685	684	rcu_read_unlock();
686	685	return 0;
...	...	@@ -414,8 +414,7 @@
414	414
415	415	ipip_ecn_decapsulate(iph, skb);
416	416
417		- if (netif_rx(skb) == NET_RX_DROP)
418		- tunnel->dev->stats.rx_dropped++;
	417	+ netif_rx(skb);
419	418
420	419	rcu_read_unlock();
421	420	return 0;
...	...	@@ -768,8 +768,7 @@
768	768
769	769	dscp_ecn_decapsulate(t, ipv6h, skb);
770	770
771		- if (netif_rx(skb) == NET_RX_DROP)
772		- t->dev->stats.rx_dropped++;
	771	+ netif_rx(skb);
773	772
774	773	rcu_read_unlock();
775	774	return 0;
...	...	@@ -666,8 +666,7 @@
666	666
667	667	skb_tunnel_rx(skb, reg_dev);
668	668
669		- if (netif_rx(skb) == NET_RX_DROP)
670		- reg_dev->stats.rx_dropped++;
	669	+ netif_rx(skb);
671	670
672	671	dev_put(reg_dev);
673	672	return 0;