[TCP]: Congestion control API update.

Do some simple changes to make congestion control API faster/cleaner.
* use ktime_t rather than timeval
* merge rtt sampling into existing ack callback
  this means one indirect call versus two per ack.
* use flags bits to store options/settings

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 3 deletions

diff --git a/net/ipv4/tcp_lp.c b/net/ipv4/tcp_lp.c
index f0ebaf0e21cb..b4e062ab24a1 100644
--- a/net/ipv4/tcp_lp.c
+++ b/net/ipv4/tcp_lp.c
@@ -218,7 +218,7 @@ static u32 tcp_lp_owd_calculator(struct sock *sk)
  *   3. calc smoothed OWD (SOWD).
  * Most ideas come from the original TCP-LP implementation.
  */
-static void tcp_lp_rtt_sample(struct sock *sk, u32 usrtt)
+static void tcp_lp_rtt_sample(struct sock *sk, u32 rtt)
 {
         struct lp *lp = inet_csk_ca(sk);
         s64 mowd = tcp_lp_owd_calculator(sk);
@@ -261,11 +261,13 @@ static void tcp_lp_rtt_sample(struct sock *sk, u32 usrtt)
  * newReno in increase case.
  * We work it out by following the idea from TCP-LP's paper directly
  */
-static void tcp_lp_pkts_acked(struct sock *sk, u32 num_acked)
+static void tcp_lp_pkts_acked(struct sock *sk, u32 num_acked, ktime_t last)
 {
         struct tcp_sock *tp = tcp_sk(sk);
         struct lp *lp = inet_csk_ca(sk);
 
+        tcp_lp_rtt_sample(sk,  ktime_to_ns(net_timedelta(last)) / NSEC_PER_USEC);
+
         /* calc inference */
         if (tcp_time_stamp > tp->rx_opt.rcv_tsecr)
                 lp->inference = 3 * (tcp_time_stamp - tp->rx_opt.rcv_tsecr);
@@ -312,11 +314,11 @@ static void tcp_lp_pkts_acked(struct sock *sk, u32 num_acked)
 }
 
 static struct tcp_congestion_ops tcp_lp = {
+        .flags = TCP_CONG_RTT_STAMP,
         .init = tcp_lp_init,
         .ssthresh = tcp_reno_ssthresh,
         .cong_avoid = tcp_lp_cong_avoid,
         .min_cwnd = tcp_reno_min_cwnd,
-        .rtt_sample = tcp_lp_rtt_sample,
         .pkts_acked = tcp_lp_pkts_acked,
 
         .owner = THIS_MODULE,