mptcp: add CurrEstab MIB counter support
Add a new MIB counter named MPTCP_MIB_CURRESTAB to count current
established MPTCP connections, similar to TCP_MIB_CURRESTAB. This is
useful to quickly list the number of MPTCP connections without having to
iterate over all of them.
This patch adds a new helper function mptcp_set_state(): if the state
switches from or to ESTABLISHED state, this newly added counter is
incremented. This helper is going to be used in the following patch.
Similar to MPTCP_INC_STATS(), a new helper called MPTCP_DEC_STATS() is
also needed to decrement a MIB counter.
Signed-off-by: Geliang Tang <geliang.tang@linux.dev>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 91e5845d..a77a609 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -2871,6 +2871,24 @@ void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how)
release_sock(ssk);
}
+void mptcp_set_state(struct sock *sk, int state)
+{
+ int oldstate = sk->sk_state;
+
+ switch (state) {
+ case TCP_ESTABLISHED:
+ if (oldstate != TCP_ESTABLISHED)
+ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_CURRESTAB);
+ break;
+
+ default:
+ if (oldstate == TCP_ESTABLISHED)
+ MPTCP_DEC_STATS(sock_net(sk), MPTCP_MIB_CURRESTAB);
+ }
+
+ inet_sk_state_store(sk, state);
+}
+
static const unsigned char new_state[16] = {
/* current state: new state: action: */
[0 /* (Invalid) */] = TCP_CLOSE,
