[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>
diff --git a/net/ipv4/tcp_westwood.c b/net/ipv4/tcp_westwood.c
index ae1026a..e61e09d 100644
--- a/net/ipv4/tcp_westwood.c
+++ b/net/ipv4/tcp_westwood.c
@@ -100,7 +100,7 @@
  * Called after processing group of packets.
  * but all westwood needs is the last sample of srtt.
  */
-static void tcp_westwood_pkts_acked(struct sock *sk, u32 cnt)
+static void tcp_westwood_pkts_acked(struct sock *sk, u32 cnt, ktime_t last)
 {
 	struct westwood *w = inet_csk_ca(sk);
 	if (cnt > 0)