check RTT lock, not MTU lock

SCCS-vsn: sys/netinet/tcp_input.c 7.26

diff --git a/usr/src/sys/netinet/tcp_input.c b/usr/src/sys/netinet/tcp_input.c
index 18477ae..49cb972 100644 (file)
--- a/usr/src/sys/netinet/tcp_input.c
+++ b/usr/src/sys/netinet/tcp_input.c
@@ -4,7 +4,7 @@
  *
  * %sccs.include.redist.c%
  *
  *
  * %sccs.include.redist.c%
  *

- *     @(#)tcp_input.c 7.25 (Berkeley) %G%
+ *     @(#)tcp_input.c 7.26 (Berkeley) %G%

  */
 
 #include "param.h"
  */
 
 #include "param.h"


@@ -1312,7 +1312,7 @@ tcp_xmit_timer(tp)
                /* 
                 * No rtt measurement yet - use the unsmoothed rtt.
                 * Set the variance to half the rtt (so our first
                /* 
                 * No rtt measurement yet - use the unsmoothed rtt.
                 * Set the variance to half the rtt (so our first

-                * retransmit happens at 2*rtt)
+                * retransmit happens at 3*rtt).

                 */
                tp->t_srtt = tp->t_rtt << TCP_RTT_SHIFT;
                tp->t_rttvar = tp->t_rtt << (TCP_RTTVAR_SHIFT - 1);
                 */
                tp->t_srtt = tp->t_rtt << TCP_RTT_SHIFT;
                tp->t_rttvar = tp->t_rtt << (TCP_RTTVAR_SHIFT - 1);


@@ -1398,7 +1398,11 @@ tcp_mss(tp, offer)
         * to scaled multiples of the slow timeout timer.
         */
        if (tp->t_srtt == 0 && (rtt = rt->rt_rmx.rmx_rtt)) {
         * to scaled multiples of the slow timeout timer.
         */
        if (tp->t_srtt == 0 && (rtt = rt->rt_rmx.rmx_rtt)) {

-               if (rt->rt_rmx.rmx_locks & RTV_MTU)
+               /*
+                * XXX the lock bit for MTU indicates that the value
+                * is also a minimum value; this is subject to time.
+                */
+               if (rt->rt_rmx.rmx_locks & RTV_RTT)

                        tp->t_rttmin = rtt / (RTM_RTTUNIT / PR_SLOWHZ);
                tp->t_srtt = rtt / (RTM_RTTUNIT / (PR_SLOWHZ * TCP_RTT_SCALE));
                if (rt->rt_rmx.rmx_rttvar)
                        tp->t_rttmin = rtt / (RTM_RTTUNIT / PR_SLOWHZ);
                tp->t_srtt = rtt / (RTM_RTTUNIT / (PR_SLOWHZ * TCP_RTT_SCALE));
                if (rt->rt_rmx.rmx_rttvar)