ip6tnl: percpu stats accounting
Maintain per_cpu tx_bytes, tx_packets, rx_bytes, rx_packets.
Other seldom used fields are kept in netdev->stats structure, possibly
unsafe.
This is a preliminary work to support lockless transmit path, and
correct RX stats, that are already unsafe.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index f6d9f68..8be3c45 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -75,7 +75,7 @@
(addr)->s6_addr32[2] ^ (addr)->s6_addr32[3]) & \
(HASH_SIZE - 1))
-static void ip6_tnl_dev_init(struct net_device *dev);
+static int ip6_tnl_dev_init(struct net_device *dev);
static void ip6_tnl_dev_setup(struct net_device *dev);
static int ip6_tnl_net_id __read_mostly;
@@ -88,6 +88,34 @@
struct ip6_tnl __rcu **tnls[2];
};
+/* often modified stats are per cpu, other are shared (netdev->stats) */
+struct pcpu_tstats {
+ unsigned long rx_packets;
+ unsigned long rx_bytes;
+ unsigned long tx_packets;
+ unsigned long tx_bytes;
+};
+
+static struct net_device_stats *ip6_get_stats(struct net_device *dev)
+{
+ struct pcpu_tstats sum = { 0 };
+ int i;
+
+ for_each_possible_cpu(i) {
+ const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
+
+ sum.rx_packets += tstats->rx_packets;
+ sum.rx_bytes += tstats->rx_bytes;
+ sum.tx_packets += tstats->tx_packets;
+ sum.tx_bytes += tstats->tx_bytes;
+ }
+ dev->stats.rx_packets = sum.rx_packets;
+ dev->stats.rx_bytes = sum.rx_bytes;
+ dev->stats.tx_packets = sum.tx_packets;
+ dev->stats.tx_bytes = sum.tx_bytes;
+ return &dev->stats;
+}
+
/*
* Locking : hash tables are protected by RCU and RTNL
*/
@@ -216,6 +244,12 @@
}
}
+static void ip6_dev_free(struct net_device *dev)
+{
+ free_percpu(dev->tstats);
+ free_netdev(dev);
+}
+
/**
* ip6_tnl_create() - create a new tunnel
* @p: tunnel parameters
@@ -254,7 +288,9 @@
t = netdev_priv(dev);
t->parms = *p;
- ip6_tnl_dev_init(dev);
+ err = ip6_tnl_dev_init(dev);
+ if (err < 0)
+ goto failed_free;
if ((err = register_netdevice(dev)) < 0)
goto failed_free;
@@ -264,7 +300,7 @@
return t;
failed_free:
- free_netdev(dev);
+ ip6_dev_free(dev);
failed:
return NULL;
}
@@ -700,6 +736,8 @@
if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr,
&ipv6h->daddr)) != NULL) {
+ struct pcpu_tstats *tstats;
+
if (t->parms.proto != ipproto && t->parms.proto != 0) {
rcu_read_unlock();
goto discard;
@@ -722,7 +760,11 @@
skb->pkt_type = PACKET_HOST;
memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
- skb_tunnel_rx(skb, t->dev);
+ tstats = this_cpu_ptr(t->dev->tstats);
+ tstats->rx_packets++;
+ tstats->rx_bytes += skb->len;
+
+ __skb_tunnel_rx(skb, t->dev);
dscp_ecn_decapsulate(t, ipv6h, skb);
@@ -935,8 +977,10 @@
err = ip6_local_out(skb);
if (net_xmit_eval(err) == 0) {
- stats->tx_bytes += pkt_len;
- stats->tx_packets++;
+ struct pcpu_tstats *tstats = this_cpu_ptr(t->dev->tstats);
+
+ tstats->tx_bytes += pkt_len;
+ tstats->tx_packets++;
} else {
stats->tx_errors++;
stats->tx_aborted_errors++;
@@ -1301,12 +1345,14 @@
static const struct net_device_ops ip6_tnl_netdev_ops = {
- .ndo_uninit = ip6_tnl_dev_uninit,
+ .ndo_uninit = ip6_tnl_dev_uninit,
.ndo_start_xmit = ip6_tnl_xmit,
- .ndo_do_ioctl = ip6_tnl_ioctl,
+ .ndo_do_ioctl = ip6_tnl_ioctl,
.ndo_change_mtu = ip6_tnl_change_mtu,
+ .ndo_get_stats = ip6_get_stats,
};
+
/**
* ip6_tnl_dev_setup - setup virtual tunnel device
* @dev: virtual device associated with tunnel
@@ -1318,7 +1364,7 @@
static void ip6_tnl_dev_setup(struct net_device *dev)
{
dev->netdev_ops = &ip6_tnl_netdev_ops;
- dev->destructor = free_netdev;
+ dev->destructor = ip6_dev_free;
dev->type = ARPHRD_TUNNEL6;
dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr);
@@ -1334,12 +1380,17 @@
* @dev: virtual device associated with tunnel
**/
-static inline void
+static inline int
ip6_tnl_dev_init_gen(struct net_device *dev)
{
struct ip6_tnl *t = netdev_priv(dev);
+
t->dev = dev;
strcpy(t->parms.name, dev->name);
+ dev->tstats = alloc_percpu(struct pcpu_tstats);
+ if (!dev->tstats)
+ return -ENOMEM;
+ return 0;
}
/**
@@ -1347,11 +1398,15 @@
* @dev: virtual device associated with tunnel
**/
-static void ip6_tnl_dev_init(struct net_device *dev)
+static int ip6_tnl_dev_init(struct net_device *dev)
{
struct ip6_tnl *t = netdev_priv(dev);
- ip6_tnl_dev_init_gen(dev);
+ int err = ip6_tnl_dev_init_gen(dev);
+
+ if (err)
+ return err;
ip6_tnl_link_config(t);
+ return 0;
}
/**
@@ -1361,16 +1416,20 @@
* Return: 0
**/
-static void __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
+static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
{
struct ip6_tnl *t = netdev_priv(dev);
struct net *net = dev_net(dev);
struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
+ int err = ip6_tnl_dev_init_gen(dev);
- ip6_tnl_dev_init_gen(dev);
+ if (err)
+ return err;
+
t->parms.proto = IPPROTO_IPV6;
dev_hold(dev);
rcu_assign_pointer(ip6n->tnls_wc[0], t);
+ return 0;
}
static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
@@ -1420,7 +1479,9 @@
goto err_alloc_dev;
dev_net_set(ip6n->fb_tnl_dev, net);
- ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
+ err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
+ if (err < 0)
+ goto err_register;
err = register_netdev(ip6n->fb_tnl_dev);
if (err < 0)
@@ -1428,7 +1489,7 @@
return 0;
err_register:
- free_netdev(ip6n->fb_tnl_dev);
+ ip6_dev_free(ip6n->fb_tnl_dev);
err_alloc_dev:
return err;
}