tcp: replace cnt & rtt with struct in pkts_acked()

Replace 2 arguments (cnt and rtt) in the congestion control modules'
pkts_acked() function with a struct. This will allow adding more
information without having to modify existing congestion control
modules (tcp_nv in particular needs bytes in flight when packet
was sent).

As proposed by Neal Cardwell in his comments to the tcp_nv patch.

Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 2 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index a914e0607895..d6c8f4cd0800 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3248,8 +3248,12 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
                 tcp_rearm_rto(sk);
         }
 
-        if (icsk->icsk_ca_ops->pkts_acked)
-                icsk->icsk_ca_ops->pkts_acked(sk, pkts_acked, ca_rtt_us);
+        if (icsk->icsk_ca_ops->pkts_acked) {
+                struct ack_sample sample = { .pkts_acked = pkts_acked,
+                                             .rtt_us = ca_rtt_us };
+
+                icsk->icsk_ca_ops->pkts_acked(sk, &sample);
+        }
 
 #if FASTRETRANS_DEBUG > 0
         WARN_ON((int)tp->sacked_out < 0);