net: tracepoint: replace tcp_set_state tracepoint with inet_sock_set_state tracepoint

As sk_state is a common field for struct sock, so the state
transition tracepoint should not be a TCP specific feature.
Currently it traces all AF_INET state transition, so I rename this
tracepoint to inet_sock_set_state tracepoint with some minor changes and move it
into trace/events/sock.h.
We dont need to create a file named trace/events/inet_sock.h for this one single
tracepoint.

Two helpers are introduced to trace sk_state transition
    - void inet_sk_state_store(struct sock *sk, int newstate);
    - void inet_sk_set_state(struct sock *sk, int state);
As trace header should not be included in other header files,
so they are defined in sock.c.

The protocol such as SCTP maybe compiled as a ko, hence export
inet_sk_set_state().

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 0 deletions

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index f00499a46927..bab98a4fedad 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -121,6 +121,7 @@
 #endif
 #include <net/l3mdev.h>
 
+#include <trace/events/sock.h>
 
 /* The inetsw table contains everything that inet_create needs to
  * build a new socket.
@@ -1220,6 +1221,19 @@ int inet_sk_rebuild_header(struct sock *sk)
 }
 EXPORT_SYMBOL(inet_sk_rebuild_header);
 
+void inet_sk_set_state(struct sock *sk, int state)
+{
+	trace_inet_sock_set_state(sk, sk->sk_state, state);
+	sk->sk_state = state;
+}
+EXPORT_SYMBOL(inet_sk_set_state);
+
+void inet_sk_state_store(struct sock *sk, int newstate)
+{
+	trace_inet_sock_set_state(sk, sk->sk_state, newstate);
+	smp_store_release(&sk->sk_state, newstate);
+}
+
 struct sk_buff *inet_gso_segment(struct sk_buff *skb,
 				 netdev_features_t features)
 {