[TCP]: congestion control API pass RTT in microseconds

This patch changes the API for the callback that is done after an ACK is
received. It solves a couple of issues:

  * Some congestion controls want higher resolution value of RTT
    (controlled by TCP_CONG_RTT_SAMPLE flag). These don't really want a ktime, but
    all compute a RTT in microseconds.

  * Other congestion control could use RTT at jiffies resolution.

To keep API consistent the units should be the same for both cases, just the
resolution should change.

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

1 files changed, 1 insertions, 1 deletions

diff --git a/net/ipv4/tcp_vegas.h b/net/ipv4/tcp_vegas.h
index 502fa8183634..6c0eea2f8249 100644
--- a/net/ipv4/tcp_vegas.h
+++ b/net/ipv4/tcp_vegas.h
@@ -17,7 +17,7 @@ struct vegas {
 
 extern void tcp_vegas_init(struct sock *sk);
 extern void tcp_vegas_state(struct sock *sk, u8 ca_state);
-extern void tcp_vegas_pkts_acked(struct sock *sk, u32 cnt, ktime_t last);
+extern void tcp_vegas_pkts_acked(struct sock *sk, u32 cnt, s32 rtt_us);
 extern void tcp_vegas_cwnd_event(struct sock *sk, enum tcp_ca_event event);
 extern void tcp_vegas_get_info(struct sock *sk, u32 ext, struct sk_buff *skb);