tcp: don't clear retransmit_skb_hint when not necessary

Most importantly avoid doing it with cumulative ACK. Not clearing
means that we no longer need n^2 processing in resolution of each
fast recovery.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 1 deletions

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 220f54cf42ec..ea815723d414 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1037,10 +1037,15 @@ static inline void tcp_mib_init(struct net *net)
 }
 
 /* from STCP */
-static inline void tcp_clear_all_retrans_hints(struct tcp_sock *tp)
+static inline void tcp_clear_retrans_hints_partial(struct tcp_sock *tp)
 {
         tp->lost_skb_hint = NULL;
         tp->scoreboard_skb_hint = NULL;
+}
+
+static inline void tcp_clear_all_retrans_hints(struct tcp_sock *tp)
+{
+        tcp_clear_retrans_hints_partial(tp);
         tp->retransmit_skb_hint = NULL;
 }