Merge branch 'replace-tcp_set_state-tracepoint-with-inet_sock_set_state'

Yafang Shao says:

====================
replace tcp_set_state tracepoint with inet_sock_set_state

According to the discussion in the mail thread
https://patchwork.kernel.org/patch/10099243/,
tcp_set_state tracepoint is renamed to inet_sock_set_state tracepoint and is
moved to include/trace/events/sock.h.

With this new tracepoint, we can trace AF_INET/AF_INET6 sock state transitions.
As there's only one single tracepoint for inet, so I didn't create a new trace
file named trace/events/inet_sock.h, and just place it in
include/trace/events/sock.h

Currently TCP/DCCP/SCTP state transitions are traced with this tracepoint.

- Why not more protocol ?
If we really think that anonter protocol should be traced, I will modify the
code to trace it.
I just want to make the code easy and not output useless information.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 25 insertions, 0 deletions

diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 39efb968b7a4..0a671c32d6b9 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -291,6 +291,31 @@ static inline void inet_sk_copy_descendant(struct sock *sk_to,
 
 int inet_sk_rebuild_header(struct sock *sk);
 
+/**
+ * inet_sk_state_load - read sk->sk_state for lockless contexts
+ * @sk: socket pointer
+ *
+ * Paired with inet_sk_state_store(). Used in places we don't hold socket lock:
+ * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ...
+ */
+static inline int inet_sk_state_load(const struct sock *sk)
+{
+	/* state change might impact lockless readers. */
+	return smp_load_acquire(&sk->sk_state);
+}
+
+/**
+ * inet_sk_state_store - update sk->sk_state
+ * @sk: socket pointer
+ * @newstate: new state
+ *
+ * Paired with inet_sk_state_load(). Should be used in contexts where
+ * state change might impact lockless readers.
+ */
+void inet_sk_state_store(struct sock *sk, int newstate);
+
+void inet_sk_set_state(struct sock *sk, int state);
+
 static inline unsigned int __inet_ehashfn(const __be32 laddr,
 					  const __u16 lport,
 					  const __be32 faddr,