[PATCH v1 net-next 11/15] fou: Store struct sock in struct fou.

[Kuniyuki Iwashima <kuniyu@google.com>]

fou does not need to access struct socket itself in the fast
path; it only reads struct sock, and struct socket is only used
for tunnel setup and teardown.

Let's store struct sock directly in struct fou.

fou_release() frees struct fou with kfree_rcu(), so fou no
longer needs synchronize_rcu() in udp_tunnel_sock_release().

Note that the error path in fou_create() looks buggy; once the
tunnel is set up and fou_add_to_port_list() fails, struct fou
should be freed with kfree_rcu() _after_ udp_tunnel_sock_release().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
---
 net/ipv4/fou_core.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/net/ipv4/fou_core.c b/net/ipv4/fou_core.c
index 6bed0e1dbe0e..865bd7205122 100644
--- a/net/ipv4/fou_core.c
+++ b/net/ipv4/fou_core.c
@@ -22,7 +22,7 @@
 #include "fou_nl.h"
 
 struct fou {
-	struct socket *sock;
+	struct sock *sk;
 	u8 protocol;
 	u8 flags;
 	__be16 port;
@@ -508,8 +508,8 @@ static int gue_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff)
 
 static bool fou_cfg_cmp(struct fou *fou, struct fou_cfg *cfg)
 {
-	struct sock *sk = fou->sock->sk;
 	struct udp_port_cfg *udp_cfg = &cfg->udp_config;
+	struct sock *sk = fou->sk;
 
 	if (fou->family != udp_cfg->family ||
 	    fou->port != udp_cfg->local_udp_port ||
@@ -559,7 +559,7 @@ static int fou_add_to_port_list(struct net *net, struct fou *fou,
 static void fou_release(struct fou *fou)
 {
 	list_del(&fou->list);
-	udp_tunnel_sock_release(fou->sock->sk);
+	udp_tunnel_sock_release(fou->sk);
 	kfree_rcu(fou, rcu);
 }
 
@@ -590,7 +590,7 @@ static int fou_create(struct net *net, struct fou_cfg *cfg,
 	fou->family = cfg->udp_config.family;
 	fou->flags = cfg->flags;
 	fou->type = cfg->type;
-	fou->sock = sock;
+	fou->sk = sk;
 
 	memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
 	tunnel_cfg.encap_type = 1;
@@ -776,9 +776,9 @@ int fou_nl_del_doit(struct sk_buff *skb, struct genl_info *info)
 
 static int fou_fill_info(struct fou *fou, struct sk_buff *msg)
 {
-	struct sock *sk = fou->sock->sk;
+	struct sock *sk = fou->sk;
 
-	if (nla_put_u8(msg, FOU_ATTR_AF, fou->sock->sk->sk_family) ||
+	if (nla_put_u8(msg, FOU_ATTR_AF, sk->sk_family) ||
 	    nla_put_be16(msg, FOU_ATTR_PORT, fou->port) ||
 	    nla_put_be16(msg, FOU_ATTR_PEER_PORT, sk->sk_dport) ||
 	    nla_put_u8(msg, FOU_ATTR_IPPROTO, fou->protocol) ||
@@ -790,7 +790,7 @@ static int fou_fill_info(struct fou *fou, struct sk_buff *msg)
 		if (nla_put_flag(msg, FOU_ATTR_REMCSUM_NOPARTIAL))
 			return -1;
 
-	if (fou->sock->sk->sk_family == AF_INET) {
+	if (sk->sk_family == AF_INET) {
 		if (nla_put_in_addr(msg, FOU_ATTR_LOCAL_V4, sk->sk_rcv_saddr))
 			return -1;
 
-- 
2.54.0.545.g6539524ca2-goog