net: sock: replace sk_state_load with inet_sk_state_load and remove sk_state_store

sk_state_load is only used by AF_INET/AF_INET6, so rename it to
inet_sk_state_load and move it into inet_sock.h.

sk_state_store is removed as it is not used any more.

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

1 files changed, 24 insertions, 1 deletions

diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index a3431a4ff9cc..0a671c32d6b9 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -290,9 +290,32 @@ static inline void inet_sk_copy_descendant(struct sock *sk_to,
 #endif
 
 int inet_sk_rebuild_header(struct sock *sk);
-void inet_sk_set_state(struct sock *sk, int state);
+
+/**
+ * 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,