tcp: record pkts sent and retransmistted

Add two stats in SCM_TIMESTAMPING_OPT_STATS:

TCP_NLA_DATA_SEGS_OUT: total data packets sent including retransmission
TCP_NLA_TOTAL_RETRANS: total data packets retransmitted

The names are picked to be consistent with corresponding fields in
TCP_INFO. This allows applications that are using the timestamping
API to measure latency stats to also retrive retransmission rate
of application write.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 1 deletions

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 2ed472ebf3b5..b751abc56935 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2870,7 +2870,7 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk)
 	struct sk_buff *stats;
 	struct tcp_info info;
 
-	stats = alloc_skb(3 * nla_total_size_64bit(sizeof(u64)), GFP_ATOMIC);
+	stats = alloc_skb(5 * nla_total_size_64bit(sizeof(u64)), GFP_ATOMIC);
 	if (!stats)
 		return NULL;
 
@@ -2881,6 +2881,10 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk)
 			  info.tcpi_rwnd_limited, TCP_NLA_PAD);
 	nla_put_u64_64bit(stats, TCP_NLA_SNDBUF_LIMITED,
 			  info.tcpi_sndbuf_limited, TCP_NLA_PAD);
+	nla_put_u64_64bit(stats, TCP_NLA_DATA_SEGS_OUT,
+			  tp->data_segs_out, TCP_NLA_PAD);
+	nla_put_u64_64bit(stats, TCP_NLA_TOTAL_RETRANS,
+			  tp->total_retrans, TCP_NLA_PAD);
 	return stats;
 }