mptcp: add active MPC mibs

We are not currently tracking the active MPTCP connection
attempts. Let's add the related counters.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mptcp/mib.c

@@ -10,6 +10,8 @@
 
 static const struct snmp_mib mptcp_snmp_list[] = {
 	SNMP_MIB_ITEM("MPCapableSYNRX", MPTCP_MIB_MPCAPABLEPASSIVE),
+	SNMP_MIB_ITEM("MPCapableSYNTX", MPTCP_MIB_MPCAPABLEACTIVE),
+	SNMP_MIB_ITEM("MPCapableSYNACKRX", MPTCP_MIB_MPCAPABLEACTIVEACK),
 	SNMP_MIB_ITEM("MPCapableACKRX", MPTCP_MIB_MPCAPABLEPASSIVEACK),
 	SNMP_MIB_ITEM("MPCapableFallbackACK", MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK),
 	SNMP_MIB_ITEM("MPCapableFallbackSYNACK", MPTCP_MIB_MPCAPABLEACTIVEFALLBACK),

net/mptcp/mib.h

@@ -3,6 +3,8 @@
 enum linux_mptcp_mib_field {
 	MPTCP_MIB_NUM = 0,
 	MPTCP_MIB_MPCAPABLEPASSIVE,	/* Received SYN with MP_CAPABLE */
+	MPTCP_MIB_MPCAPABLEACTIVE,	/* Sent SYN with MP_CAPABLE */
+	MPTCP_MIB_MPCAPABLEACTIVEACK,	/* Received SYN/ACK with MP_CAPABLE */
 	MPTCP_MIB_MPCAPABLEPASSIVEACK,	/* Received third ACK with MP_CAPABLE */
 	MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK,/* Server-side fallback during 3-way handshake */
 	MPTCP_MIB_MPCAPABLEACTIVEFALLBACK, /* Client-side fallback during 3-way handshake */

net/mptcp/protocol.c

@@ -3228,6 +3228,8 @@ static int mptcp_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 		MPTCP_INC_STATS(sock_net(ssock->sk), MPTCP_MIB_TOKENFALLBACKINIT);
 		mptcp_subflow_early_fallback(msk, subflow);
 	}
+	if (likely(!__mptcp_check_fallback(msk)))
+		MPTCP_INC_STATS(sock_net(sock->sk), MPTCP_MIB_MPCAPABLEACTIVE);
 
 do_connect:
 	err = ssock->ops->connect(ssock, uaddr, addr_len, flags);

net/mptcp/subflow.c

@@ -395,6 +395,7 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)
 		subflow->remote_key = mp_opt.sndr_key;
 		pr_debug("subflow=%p, remote_key=%llu", subflow,
 			 subflow->remote_key);
+		MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEACTIVEACK);
 		mptcp_finish_connect(sk);
 	} else if (subflow->request_join) {
 		u8 hmac[SHA256_DIGEST_SIZE];