tcp: add more warn of socket in tcp_send_loss_probe()

Add two fields to print in the helper which here covers tcp_send_loss_probe().

Link: https://lore.kernel.org/all/[email protected]/
Suggested-by: Paolo Abeni <[email protected]>
Signed-off-by: Jason Xing <[email protected]>
Cc: Neal Cardwell <[email protected]>
Reviewed-by: David Ahern <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: JasonXing

include/net/tcp.h

@@ -2433,8 +2433,9 @@ void tcp_plb_update_state_upon_rto(struct sock *sk, struct tcp_plb_state *plb);
 static inline void tcp_warn_once(const struct sock *sk, bool cond, const char *str)
 {
 	WARN_ONCE(cond,
-		  "%sout:%u sacked:%u lost:%u retrans:%u tlp_high_seq:%u sk_state:%u ca_state:%u advmss:%u mss_cache:%u pmtu:%u\n",
+		  "%scwn:%u out:%u sacked:%u lost:%u retrans:%u tlp_high_seq:%u sk_state:%u ca_state:%u advmss:%u mss_cache:%u pmtu:%u\n",
 		  str,
+		  tcp_snd_cwnd(tcp_sk(sk)),
 		  tcp_sk(sk)->packets_out, tcp_sk(sk)->sacked_out,
 		  tcp_sk(sk)->lost_out, tcp_sk(sk)->retrans_out,
 		  tcp_sk(sk)->tlp_high_seq, sk->sk_state,

net/ipv4/tcp_output.c

@@ -2954,9 +2954,7 @@ void tcp_send_loss_probe(struct sock *sk)
 	}
 	skb = skb_rb_last(&sk->tcp_rtx_queue);
 	if (unlikely(!skb)) {
-		WARN_ONCE(tp->packets_out,
-			  "invalid inflight: %u state %u cwnd %u mss %d\n",
-			  tp->packets_out, sk->sk_state, tcp_snd_cwnd(tp), mss);
+		tcp_warn_once(sk, tp->packets_out, "invalid inflight: ");
 		smp_store_release(&inet_csk(sk)->icsk_pending, 0);
 		return;
 	}