[PATCH net-next v2] ip_tunnel: Move stats update to iptunnel_xmit()

[PATCH net-next v2] ip_tunnel: Move stats update to iptunnel_xmit()

[Pravin B Shelar]

By moving stats update into iptunnel_xmit(), we can simplify
iptunnel_xmit() usage. With this change there is no need to
call another function (iptunnel_xmit_stats()) to update stats
in tunnel xmit code path.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
---
v1-v2:
- keep iptunnel_xmit_stats() stats update same.
---
 drivers/net/geneve.c      | 17 ++++++++---------
 drivers/net/vxlan.c       |  9 ++++-----
 include/net/ip6_tunnel.h  | 17 ++++-------------
 include/net/ip_tunnels.h  | 24 +++++++++++++-----------
 include/net/udp_tunnel.h  |  8 ++++----
 net/ipv4/ip_gre.c         |  7 +++----
 net/ipv4/ip_tunnel.c      |  7 ++-----
 net/ipv4/ip_tunnel_core.c |  9 +++++----
 net/ipv4/ip_vti.c         |  2 +-
 net/ipv4/udp_tunnel.c     | 11 +++++------
 net/ipv6/sit.c            |  7 ++-----
 net/tipc/udp_media.c      | 12 +++---------
 12 files changed, 54 insertions(+), 76 deletions(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index e6e0092..20dd664 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -918,12 +918,11 @@ static netdev_tx_t geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 		ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);
 		df = 0;
 	}
-	err = udp_tunnel_xmit_skb(rt, gs4->sock->sk, skb, fl4.saddr, fl4.daddr,
-				  tos, ttl, df, sport, geneve->dst_port,
-				  !net_eq(geneve->net, dev_net(geneve->dev)),
-				  !(flags & GENEVE_F_UDP_CSUM));
+	udp_tunnel_xmit_skb(rt, gs4->sock->sk, skb, fl4.saddr, fl4.daddr,
+			    tos, ttl, df, sport, geneve->dst_port,
+			    !net_eq(geneve->net, dev_net(geneve->dev)),
+			    !(flags & GENEVE_F_UDP_CSUM));
 
-	iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
 	return NETDEV_TX_OK;
 
 tx_error:
@@ -1005,10 +1004,10 @@ static netdev_tx_t geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 			ttl = 1;
 		ttl = ttl ? : ip6_dst_hoplimit(dst);
 	}
-	err = udp_tunnel6_xmit_skb(dst, gs6->sock->sk, skb, dev,
-				   &fl6.saddr, &fl6.daddr, prio, ttl,
-				   sport, geneve->dst_port,
-				   !!(flags & GENEVE_F_UDP_ZERO_CSUM6_TX));
+	udp_tunnel6_xmit_skb(dst, gs6->sock->sk, skb, dev,
+			     &fl6.saddr, &fl6.daddr, prio, ttl,
+			     sport, geneve->dst_port,
+			     !!(flags & GENEVE_F_UDP_ZERO_CSUM6_TX));
 	return NETDEV_TX_OK;
 
 tx_error:
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index ba363ce..fecf7b6 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -1841,9 +1841,10 @@ static int vxlan_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *sk
 
 	skb_set_inner_protocol(skb, htons(ETH_P_TEB));
 
-	return udp_tunnel_xmit_skb(rt, sk, skb, src, dst, tos,
-				   ttl, df, src_port, dst_port, xnet,
-				   !(vxflags & VXLAN_F_UDP_CSUM));
+	udp_tunnel_xmit_skb(rt, sk, skb, src, dst, tos, ttl, df,
+			    src_port, dst_port, xnet,
+			    !(vxflags & VXLAN_F_UDP_CSUM));
+	return 0;
 }
 
 #if IS_ENABLED(CONFIG_IPV6)
@@ -2056,8 +2057,6 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 			skb = NULL;
 			goto rt_tx_error;
 		}
-
-		iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
 #if IS_ENABLED(CONFIG_IPV6)
 	} else {
 		struct dst_entry *ndst;
diff --git a/include/net/ip6_tunnel.h b/include/net/ip6_tunnel.h
index ff788b6..2ef06cd 100644
--- a/include/net/ip6_tunnel.h
+++ b/include/net/ip6_tunnel.h
@@ -5,6 +5,7 @@
 #include <linux/netdevice.h>
 #include <linux/if_tunnel.h>
 #include <linux/ip6_tunnel.h>
+#include <net/ip_tunnels.h>
 
 #define IP6TUNNEL_ERR_TIMEO (30*HZ)
 
@@ -83,22 +84,12 @@ int ip6_tnl_get_iflink(const struct net_device *dev);
 static inline void ip6tunnel_xmit(struct sock *sk, struct sk_buff *skb,
 				  struct net_device *dev)
 {
-	struct net_device_stats *stats = &dev->stats;
 	int pkt_len, err;
 
 	pkt_len = skb->len - skb_inner_network_offset(skb);
 	err = ip6_local_out(dev_net(skb_dst(skb)->dev), sk, skb);
-
-	if (net_xmit_eval(err) == 0) {
-		struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats);
-		u64_stats_update_begin(&tstats->syncp);
-		tstats->tx_bytes += pkt_len;
-		tstats->tx_packets++;
-		u64_stats_update_end(&tstats->syncp);
-		put_cpu_ptr(tstats);
-	} else {
-		stats->tx_errors++;
-		stats->tx_aborted_errors++;
-	}
+	if (likely(!net_xmit_eval(err)))
+		err = pkt_len;
+	iptunnel_xmit_stats(dev, err);
 }
 #endif
diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
index 62a750a..4df8f4e 100644
--- a/include/net/ip_tunnels.h
+++ b/include/net/ip_tunnels.h
@@ -273,32 +273,34 @@ static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
 }
 
 int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto);
-int iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
-		  __be32 src, __be32 dst, u8 proto,
-		  u8 tos, u8 ttl, __be16 df, bool xnet);
+void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
+		   __be32 src, __be32 dst, u8 proto,
+		   u8 tos, u8 ttl, __be16 df, bool xnet);
 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md,
 					     gfp_t flags);
 
 struct sk_buff *iptunnel_handle_offloads(struct sk_buff *skb, bool gre_csum,
 					 int gso_type_mask);
 
-static inline void iptunnel_xmit_stats(int err,
-				       struct net_device_stats *err_stats,
-				       struct pcpu_sw_netstats __percpu *stats)
+static inline void iptunnel_xmit_stats(struct net_device *dev, int err)
 {
 	if (err > 0) {
-		struct pcpu_sw_netstats *tstats = get_cpu_ptr(stats);
+		struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats);
 
 		u64_stats_update_begin(&tstats->syncp);
 		tstats->tx_bytes += err;
 		tstats->tx_packets++;
 		u64_stats_update_end(&tstats->syncp);
 		put_cpu_ptr(tstats);
-	} else if (err < 0) {
-		err_stats->tx_errors++;
-		err_stats->tx_aborted_errors++;
 	} else {
-		err_stats->tx_dropped++;
+		struct net_device_stats *err_stats = &dev->stats;
+
+		if (err < 0) {
+			err_stats->tx_errors++;
+			err_stats->tx_aborted_errors++;
+		} else {
+			err_stats->tx_dropped++;
+		}
 	}
 }
 
diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h
index cb2f89f..cca2ad3 100644
--- a/include/net/udp_tunnel.h
+++ b/include/net/udp_tunnel.h
@@ -78,10 +78,10 @@ void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
 			   struct udp_tunnel_sock_cfg *sock_cfg);
 
 /* Transmit the skb using UDP encapsulation. */
-int udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
-			__be32 src, __be32 dst, __u8 tos, __u8 ttl,
-			__be16 df, __be16 src_port, __be16 dst_port,
-			bool xnet, bool nocheck);
+void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
+			 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
+			 __be16 df, __be16 src_port, __be16 dst_port,
+			 bool xnet, bool nocheck);
 
 #if IS_ENABLED(CONFIG_IPV6)
 int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sock *sk,
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 04a48c0..7c51c4e 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -561,10 +561,9 @@ static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev)
 		     tunnel_id_to_key(tun_info->key.tun_id), 0);
 
 	df = key->tun_flags & TUNNEL_DONT_FRAGMENT ?  htons(IP_DF) : 0;
-	err = iptunnel_xmit(skb->sk, rt, skb, fl.saddr,
-			    key->u.ipv4.dst, IPPROTO_GRE,
-			    key->tos, key->ttl, df, false);
-	iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
+
+	iptunnel_xmit(skb->sk, rt, skb, fl.saddr, key->u.ipv4.dst, IPPROTO_GRE,
+		      key->tos, key->ttl, df, false);
 	return;
 
 err_free_rt:
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 0f6e9ee..c7bd72e 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -656,7 +656,6 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 	struct rtable *rt;		/* Route to the other host */
 	unsigned int max_headroom;	/* The extra header space needed */
 	__be32 dst;
-	int err;
 	bool connected;
 
 	inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
@@ -794,10 +793,8 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 		return;
 	}
 
-	err = iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol,
-			    tos, ttl, df, !net_eq(tunnel->net, dev_net(dev)));
-	iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
-
+	iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
+		      df, !net_eq(tunnel->net, dev_net(dev)));
 	return;
 
 #if IS_ENABLED(CONFIG_IPV6)
diff --git a/net/ipv4/ip_tunnel_core.c b/net/ipv4/ip_tunnel_core.c
index 1db8418..eb52ce9 100644
--- a/net/ipv4/ip_tunnel_core.c
+++ b/net/ipv4/ip_tunnel_core.c
@@ -47,12 +47,13 @@
 #include <net/rtnetlink.h>
 #include <net/dst_metadata.h>
 
-int iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
-		  __be32 src, __be32 dst, __u8 proto,
-		  __u8 tos, __u8 ttl, __be16 df, bool xnet)
+void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
+		   __be32 src, __be32 dst, __u8 proto,
+		   __u8 tos, __u8 ttl, __be16 df, bool xnet)
 {
 	int pkt_len = skb->len - skb_inner_network_offset(skb);
 	struct net *net = dev_net(rt->dst.dev);
+	struct net_device *dev = skb->dev;
 	struct iphdr *iph;
 	int err;
 
@@ -81,7 +82,7 @@ int iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
 	err = ip_local_out(net, sk, skb);
 	if (unlikely(net_xmit_eval(err)))
 		pkt_len = 0;
-	return pkt_len;
+	iptunnel_xmit_stats(dev, pkt_len);
 }
 EXPORT_SYMBOL_GPL(iptunnel_xmit);
 
diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
index 02d9c21..5cf10b7 100644
--- a/net/ipv4/ip_vti.c
+++ b/net/ipv4/ip_vti.c
@@ -199,7 +199,7 @@ static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev,
 	err = dst_output(tunnel->net, skb->sk, skb);
 	if (net_xmit_eval(err) == 0)
 		err = skb->len;
-	iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
+	iptunnel_xmit_stats(dev, err);
 	return NETDEV_TX_OK;
 
 tx_error_icmp:
diff --git a/net/ipv4/udp_tunnel.c b/net/ipv4/udp_tunnel.c
index aba4286..0ec0881 100644
--- a/net/ipv4/udp_tunnel.c
+++ b/net/ipv4/udp_tunnel.c
@@ -74,10 +74,10 @@ void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
 }
 EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
 
-int udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
-			__be32 src, __be32 dst, __u8 tos, __u8 ttl,
-			__be16 df, __be16 src_port, __be16 dst_port,
-			bool xnet, bool nocheck)
+void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
+			 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
+			 __be16 df, __be16 src_port, __be16 dst_port,
+			 bool xnet, bool nocheck)
 {
 	struct udphdr *uh;
 
@@ -91,8 +91,7 @@ int udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
 
 	udp_set_csum(nocheck, skb, src, dst, skb->len);
 
-	return iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP,
-			     tos, ttl, df, xnet);
+	iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP, tos, ttl, df, xnet);
 }
 EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb);
 
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index dcccae8..e794ef6 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -820,7 +820,6 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
 	const struct in6_addr *addr6;
 	int addr_type;
 	u8 ttl;
-	int err;
 	u8 protocol = IPPROTO_IPV6;
 	int t_hlen = tunnel->hlen + sizeof(struct iphdr);
 
@@ -983,10 +982,8 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
 
 	skb_set_inner_ipproto(skb, IPPROTO_IPV6);
 
-	err = iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr,
-			    protocol, tos, ttl, df,
-			    !net_eq(tunnel->net, dev_net(dev)));
-	iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
+	iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
+		      df, !net_eq(tunnel->net, dev_net(dev)));
 	return NETDEV_TX_OK;
 
 tx_error_icmp:
diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
index 6af78c6..d63a911 100644
--- a/net/tipc/udp_media.c
+++ b/net/tipc/udp_media.c
@@ -182,15 +182,9 @@ static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
 			goto tx_error;
 		}
 		ttl = ip4_dst_hoplimit(&rt->dst);
-		err = udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb,
-					  src->ipv4.s_addr,
-					  dst->ipv4.s_addr, 0, ttl, 0,
-					  src->udp_port, dst->udp_port,
-					  false, true);
-		if (err < 0) {
-			ip_rt_put(rt);
-			goto tx_error;
-		}
+		udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
+				    dst->ipv4.s_addr, 0, ttl, 0, src->udp_port,
+				    dst->udp_port, false, true);
 #if IS_ENABLED(CONFIG_IPV6)
 	} else {
 		struct dst_entry *ndst;
-- 
1.8.3.1

Re: [PATCH net-next v2] ip_tunnel: Move stats update to iptunnel_xmit()

[David Miller]

From: Pravin B Shelar <pshelar@nicira.com>
Date: Wed, 23 Dec 2015 15:52:03 -0800

>  	} else {
> -		err_stats->tx_dropped++;
> +		struct net_device_stats *err_stats = &dev->stats;
> +
> +		if (err < 0) {
> +			err_stats->tx_errors++;
> +			err_stats->tx_aborted_errors++;
> +		} else {
> +			err_stats->tx_dropped++;
> +		}

The original code did not have this "tx_dropped" code path
and you aren't explaining in your commit message why you
are adding this new behavior.

Re: [PATCH net-next v2] ip_tunnel: Move stats update to iptunnel_xmit()

[Pravin Shelar]

On Wed, Dec 23, 2015 at 6:57 PM, David Miller <davem@davemloft.net> wrote:
> From: Pravin B Shelar <pshelar@nicira.com>
> Date: Wed, 23 Dec 2015 15:52:03 -0800
>
>>       } else {
>> -             err_stats->tx_dropped++;
>> +             struct net_device_stats *err_stats = &dev->stats;
>> +
>> +             if (err < 0) {
>> +                     err_stats->tx_errors++;
>> +                     err_stats->tx_aborted_errors++;
>> +             } else {
>> +                     err_stats->tx_dropped++;
>> +             }
>
> The original code did not have this "tx_dropped" code path
> and you aren't explaining in your commit message why you
> are adding this new behavior.

There is "tx_dropped" code path in existing iptunnel_xmit_stats(). I
have only moved err_stats variable definition to local block.
There is no new behavior in this patch.

Re: [PATCH net-next v2] ip_tunnel: Move stats update to iptunnel_xmit()

[Nicolas Dichtel]

Le 24/12/2015 05:37, Pravin Shelar a écrit :
> On Wed, Dec 23, 2015 at 6:57 PM, David Miller <davem@davemloft.net> wrote:
>> From: Pravin B Shelar <pshelar@nicira.com>
>> Date: Wed, 23 Dec 2015 15:52:03 -0800
>>
>>>        } else {
>>> -             err_stats->tx_dropped++;
>>> +             struct net_device_stats *err_stats = &dev->stats;
>>> +
>>> +             if (err < 0) {
>>> +                     err_stats->tx_errors++;
>>> +                     err_stats->tx_aborted_errors++;
>>> +             } else {
>>> +                     err_stats->tx_dropped++;
>>> +             }
>>
>> The original code did not have this "tx_dropped" code path
>> and you aren't explaining in your commit message why you
>> are adding this new behavior.
>
> There is "tx_dropped" code path in existing iptunnel_xmit_stats(). I
> have only moved err_stats variable definition to local block.
> There is no new behavior in this patch.
>
Yes, I think it's ok now. There is no functional change. The prototype
of the function has changed: err_stats is not provided anymore in the arguments.

Re: [PATCH net-next v2] ip_tunnel: Move stats update to iptunnel_xmit()

[Nicolas Dichtel]

Le 24/12/2015 00:52, Pravin B Shelar a écrit :
[snip]
> @@ -83,22 +84,12 @@ int ip6_tnl_get_iflink(const struct net_device *dev);
>   static inline void ip6tunnel_xmit(struct sock *sk, struct sk_buff *skb,
>   				  struct net_device *dev)
>   {
> -	struct net_device_stats *stats = &dev->stats;
>   	int pkt_len, err;
>
>   	pkt_len = skb->len - skb_inner_network_offset(skb);
>   	err = ip6_local_out(dev_net(skb_dst(skb)->dev), sk, skb);
> -
> -	if (net_xmit_eval(err) == 0) {
> -		struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats);
> -		u64_stats_update_begin(&tstats->syncp);
> -		tstats->tx_bytes += pkt_len;
> -		tstats->tx_packets++;
> -		u64_stats_update_end(&tstats->syncp);
> -		put_cpu_ptr(tstats);
> -	} else {
> -		stats->tx_errors++;
> -		stats->tx_aborted_errors++;
> -	}
> +	if (likely(!net_xmit_eval(err)))
> +		err = pkt_len;
> +	iptunnel_xmit_stats(dev, err);
I don't think this is an equivalent change.
For example, if err == NET_XMIT_DROP, then '!net_xmit_eval(err)' is false and
iptunnel_xmit_stats() is called with err set to a positive value (NET_XMIT_DROP
value is 0x01), ie not an error.

Re: [PATCH net-next v2] ip_tunnel: Move stats update to iptunnel_xmit()

[Nicolas Dichtel]

Le 24/12/2015 00:52, Pravin B Shelar a écrit :
[snip]
> diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
> index 6af78c6..d63a911 100644
> --- a/net/tipc/udp_media.c
> +++ b/net/tipc/udp_media.c
> @@ -182,15 +182,9 @@ static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
>   			goto tx_error;
>   		}
>   		ttl = ip4_dst_hoplimit(&rt->dst);
> -		err = udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb,
> -					  src->ipv4.s_addr,
> -					  dst->ipv4.s_addr, 0, ttl, 0,
> -					  src->udp_port, dst->udp_port,
> -					  false, true);
> -		if (err < 0) {
> -			ip_rt_put(rt);
> -			goto tx_error;
> -		}
> +		udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
> +				    dst->ipv4.s_addr, 0, ttl, 0, src->udp_port,
> +				    dst->udp_port, false, true);
I don't know how tipc works, but this change is clearly suspect. What make the
error path not needed anymore after your patch?

Re: [PATCH net-next v2] ip_tunnel: Move stats update to iptunnel_xmit()

[Thadeu Lima de Souza Cascardo]

On Thu, Dec 24, 2015 at 10:21:27AM +0100, Nicolas Dichtel wrote:
> Le 24/12/2015 00:52, Pravin B Shelar a écrit :
> [snip]
> >diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
> >index 6af78c6..d63a911 100644
> >--- a/net/tipc/udp_media.c
> >+++ b/net/tipc/udp_media.c
> >@@ -182,15 +182,9 @@ static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
> >  			goto tx_error;
> >  		}
> >  		ttl = ip4_dst_hoplimit(&rt->dst);
> >-		err = udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb,
> >-					  src->ipv4.s_addr,
> >-					  dst->ipv4.s_addr, 0, ttl, 0,
> >-					  src->udp_port, dst->udp_port,
> >-					  false, true);
> >-		if (err < 0) {
> >-			ip_rt_put(rt);
> >-			goto tx_error;
> >-		}
> >+		udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
> >+				    dst->ipv4.s_addr, 0, ttl, 0, src->udp_port,
> >+				    dst->udp_port, false, true);
> I don't know how tipc works, but this change is clearly suspect. What make the
> error path not needed anymore after your patch?

I looked into it as well. As far as I see, err could only be positive or 0, so
if there is a tipc bug here, Pravin's patch introduces no regression. Or did I
fail to see how udp_tunnel_xmit_skb could return a negative value?

Cascardo.

Re: [PATCH net-next v2] ip_tunnel: Move stats update to iptunnel_xmit()

[Nicolas Dichtel]

Le 24/12/2015 13:46, Thadeu Lima de Souza Cascardo a écrit :
> On Thu, Dec 24, 2015 at 10:21:27AM +0100, Nicolas Dichtel wrote:
>> Le 24/12/2015 00:52, Pravin B Shelar a écrit :
>> [snip]
>>> diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
>>> index 6af78c6..d63a911 100644
>>> --- a/net/tipc/udp_media.c
>>> +++ b/net/tipc/udp_media.c
>>> @@ -182,15 +182,9 @@ static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
>>>   			goto tx_error;
>>>   		}
>>>   		ttl = ip4_dst_hoplimit(&rt->dst);
>>> -		err = udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb,
>>> -					  src->ipv4.s_addr,
>>> -					  dst->ipv4.s_addr, 0, ttl, 0,
>>> -					  src->udp_port, dst->udp_port,
>>> -					  false, true);
>>> -		if (err < 0) {
>>> -			ip_rt_put(rt);
>>> -			goto tx_error;
>>> -		}
>>> +		udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
>>> +				    dst->ipv4.s_addr, 0, ttl, 0, src->udp_port,
>>> +				    dst->udp_port, false, true);
>> I don't know how tipc works, but this change is clearly suspect. What make the
>> error path not needed anymore after your patch?
>
> I looked into it as well. As far as I see, err could only be positive or 0, so
> if there is a tipc bug here, Pravin's patch introduces no regression. Or did I
> fail to see how udp_tunnel_xmit_skb could return a negative value?
You're probably right. But I think it needs a separate patch in that case.


Regards,
Nicolas

Re: [PATCH net-next v2] ip_tunnel: Move stats update to iptunnel_xmit()

[Pravin Shelar]

On Thu, Dec 24, 2015 at 1:14 AM, Nicolas Dichtel
<nicolas.dichtel@6wind.com> wrote:
> Le 24/12/2015 00:52, Pravin B Shelar a écrit :
> [snip]
>>
>> @@ -83,22 +84,12 @@ int ip6_tnl_get_iflink(const struct net_device *dev);
>>   static inline void ip6tunnel_xmit(struct sock *sk, struct sk_buff *skb,
>>                                   struct net_device *dev)
>>   {
>> -       struct net_device_stats *stats = &dev->stats;
>>         int pkt_len, err;
>>
>>         pkt_len = skb->len - skb_inner_network_offset(skb);
>>         err = ip6_local_out(dev_net(skb_dst(skb)->dev), sk, skb);
>> -
>> -       if (net_xmit_eval(err) == 0) {
>> -               struct pcpu_sw_netstats *tstats =
>> get_cpu_ptr(dev->tstats);
>> -               u64_stats_update_begin(&tstats->syncp);
>> -               tstats->tx_bytes += pkt_len;
>> -               tstats->tx_packets++;
>> -               u64_stats_update_end(&tstats->syncp);
>> -               put_cpu_ptr(tstats);
>> -       } else {
>> -               stats->tx_errors++;
>> -               stats->tx_aborted_errors++;
>> -       }
>> +       if (likely(!net_xmit_eval(err)))
>> +               err = pkt_len;
>> +       iptunnel_xmit_stats(dev, err);
>
> I don't think this is an equivalent change.
> For example, if err == NET_XMIT_DROP, then '!net_xmit_eval(err)' is false
> and
> iptunnel_xmit_stats() is called with err set to a positive value
> (NET_XMIT_DROP
> value is 0x01), ie not an error.

I have sent out updated patch handle it correctly.
Thanks.