11546 Track TCP round-trip time in nanoseconds
Portions contributed by: Cody Peter Mello <cody.mello@joyent.com>
Portions contributed by: Brandon Baker <bbaker@delphix.com>
Reviewed by: Jason King <jason.king@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Dan McDonald <danmcd@joyent.com>

*** 21,31 ****
  
  /*
   * Copyright (c) 1991, 2010, Oracle and/or its affiliates. All rights reserved.
   * Copyright (c) 2011, Joyent Inc. All rights reserved.
   * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved.
!  * Copyright (c) 2013,2014 by Delphix. All rights reserved.
   * Copyright 2014, OmniTI Computer Consulting, Inc. All rights reserved.
   */
  /* Copyright (c) 1990 Mentat Inc. */
  
  #include <sys/types.h>
--- 21,31 ----
  
  /*
   * Copyright (c) 1991, 2010, Oracle and/or its affiliates. All rights reserved.
   * Copyright (c) 2011, Joyent Inc. All rights reserved.
   * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved.
!  * Copyright (c) 2013, 2016 by Delphix. All rights reserved.
   * Copyright 2014, OmniTI Computer Consulting, Inc. All rights reserved.
   */
  /* Copyright (c) 1990 Mentat Inc. */
  
  #include <sys/types.h>
*** 264,275 ****
  } tcpt_t;
  
  /*
   * Functions called directly via squeue having a prototype of edesc_t.
   */
- void            tcp_input_listener(void *arg, mblk_t *mp, void *arg2,
-     ip_recv_attr_t *ira);
  void            tcp_input_data(void *arg, mblk_t *mp, void *arg2,
      ip_recv_attr_t *ira);
  static void     tcp_linger_interrupted(void *arg, mblk_t *mp, void *arg2,
      ip_recv_attr_t *dummy);
  
--- 264,273 ----
*** 638,656 ****
                  return (error);
  
          tcp->tcp_localnet = uinfo.iulp_localnet;
  
          if (uinfo.iulp_rtt != 0) {
!                 clock_t rto;
! 
!                 tcp->tcp_rtt_sa = uinfo.iulp_rtt;
!                 tcp->tcp_rtt_sd = uinfo.iulp_rtt_sd;
!                 rto = (tcp->tcp_rtt_sa >> 3) + tcp->tcp_rtt_sd +
!                     tcps->tcps_rexmit_interval_extra +
!                     (tcp->tcp_rtt_sa >> 5);
! 
!                 TCP_SET_RTO(tcp, rto);
          }
          if (uinfo.iulp_ssthresh != 0)
                  tcp->tcp_cwnd_ssthresh = uinfo.iulp_ssthresh;
          else
                  tcp->tcp_cwnd_ssthresh = TCP_MAX_LARGEWIN;
--- 636,648 ----
                  return (error);
  
          tcp->tcp_localnet = uinfo.iulp_localnet;
  
          if (uinfo.iulp_rtt != 0) {
!                 tcp->tcp_rtt_sa = MSEC2NSEC(uinfo.iulp_rtt);
!                 tcp->tcp_rtt_sd = MSEC2NSEC(uinfo.iulp_rtt_sd);
!                 tcp->tcp_rto = tcp_calculate_rto(tcp, tcps, 0);
          }
          if (uinfo.iulp_ssthresh != 0)
                  tcp->tcp_cwnd_ssthresh = uinfo.iulp_ssthresh;
          else
                  tcp->tcp_cwnd_ssthresh = TCP_MAX_LARGEWIN;
*** 2332,2342 ****
  void
  tcp_init_values(tcp_t *tcp, tcp_t *parent)
  {
          tcp_stack_t     *tcps = tcp->tcp_tcps;
          conn_t          *connp = tcp->tcp_connp;
-         clock_t         rto;
  
          ASSERT((connp->conn_family == AF_INET &&
              connp->conn_ipversion == IPV4_VERSION) ||
              (connp->conn_family == AF_INET6 &&
              (connp->conn_ipversion == IPV4_VERSION ||
--- 2324,2333 ----
*** 2401,2416 ****
           * will be close to tcp_rexmit_interval_initial.  By doing this, we
           * allow the algorithm to adjust slowly to large fluctuations of RTT
           * during first few transmissions of a connection as seen in slow
           * links.
           */
!         tcp->tcp_rtt_sa = tcp->tcp_rto_initial << 2;
!         tcp->tcp_rtt_sd = tcp->tcp_rto_initial >> 1;
!         rto = (tcp->tcp_rtt_sa >> 3) + tcp->tcp_rtt_sd +
!             tcps->tcps_rexmit_interval_extra + (tcp->tcp_rtt_sa >> 5) +
!             tcps->tcps_conn_grace_period;
!         TCP_SET_RTO(tcp, rto);
  
          tcp->tcp_timer_backoff = 0;
          tcp->tcp_ms_we_have_waited = 0;
          tcp->tcp_last_recv_time = ddi_get_lbolt();
          tcp->tcp_cwnd_max = tcps->tcps_cwnd_max_;
--- 2392,2405 ----
           * will be close to tcp_rexmit_interval_initial.  By doing this, we
           * allow the algorithm to adjust slowly to large fluctuations of RTT
           * during first few transmissions of a connection as seen in slow
           * links.
           */
!         tcp->tcp_rtt_sa = MSEC2NSEC(tcp->tcp_rto_initial) << 2;
!         tcp->tcp_rtt_sd = MSEC2NSEC(tcp->tcp_rto_initial) >> 1;
!         tcp->tcp_rto = tcp_calculate_rto(tcp, tcps,
!             tcps->tcps_conn_grace_period);
  
          tcp->tcp_timer_backoff = 0;
          tcp->tcp_ms_we_have_waited = 0;
          tcp->tcp_last_recv_time = ddi_get_lbolt();
          tcp->tcp_cwnd_max = tcps->tcps_cwnd_max_;