struct dccp_rx_hist_entry *packet;
        struct timeval now;
        u8 win_count;
-       u32 p_prev;
+       u32 p_prev, r_sample, t_elapsed;
        int ins;
 
        if (hcrx == NULL)
                        break;
                p_prev = hcrx->ccid3hcrx_rtt;
                do_gettimeofday(&now);
-               hcrx->ccid3hcrx_rtt = timeval_usecs(&now) -
-                                    (opt_recv->dccpor_timestamp_echo -
-                                     opt_recv->dccpor_elapsed_time) * 10;
+               timeval_sub_usecs(&now, opt_recv->dccpor_timestamp_echo * 10);
+               r_sample = timeval_usecs(&now);
+               t_elapsed = opt_recv->dccpor_elapsed_time * 10;
+
+               if (unlikely(r_sample <= t_elapsed))
+                       LIMIT_NETDEBUG(KERN_WARNING
+                                      "%s: r_sample=%uus, t_elapsed=%uus\n",
+                                      __FUNCTION__, r_sample, t_elapsed);
+               else
+                       r_sample -= t_elapsed;
+
+               if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)
+                       hcrx->ccid3hcrx_rtt = r_sample;
+               else
+                       hcrx->ccid3hcrx_rtt = (hcrx->ccid3hcrx_rtt * 9) / 10 +
+                                             r_sample / 10;
+
                if (p_prev != hcrx->ccid3hcrx_rtt)
                        ccid3_pr_debug("%s, New RTT=%luus, elapsed time=%u\n",
                                       dccp_role(sk), hcrx->ccid3hcrx_rtt,