tcp_grow_window(sk, skb);
}
+static u32 tcp_rto_min(struct sock *sk)
+{
+ struct dst_entry *dst = __sk_dst_get(sk);
+ u32 rto_min = TCP_RTO_MIN;
+
+ if (dst_metric_locked(dst, RTAX_RTO_MIN))
+ rto_min = dst->metrics[RTAX_RTO_MIN-1];
+ return rto_min;
+}
+
/* Called to compute a smoothed rtt estimate. The data fed to this
* routine either comes from timestamps, or from segments that were
* known _not_ to have been retransmitted [see Karn/Partridge
if (tp->mdev_max < tp->rttvar)
tp->rttvar -= (tp->rttvar-tp->mdev_max)>>2;
tp->rtt_seq = tp->snd_nxt;
- tp->mdev_max = TCP_RTO_MIN;
+ tp->mdev_max = tcp_rto_min(sk);
}
} else {
/* no previous measure. */
tp->srtt = m<<3; /* take the measured time to be rtt */
tp->mdev = m<<1; /* make sure rto = 3*rtt */
- tp->mdev_max = tp->rttvar = max(tp->mdev, TCP_RTO_MIN);
+ tp->mdev_max = tp->rttvar = max(tp->mdev, tcp_rto_min(sk));
tp->rtt_seq = tp->snd_nxt;
}
}
}
}
-/* Numbers are taken from RFC2414. */
+/* Numbers are taken from RFC3390.
+ *
+ * John Heffner states:
+ *
+ * The RFC specifies a window of no more than 4380 bytes
+ * unless 2*MSS > 4380. Reading the pseudocode in the RFC
+ * is a bit misleading because they use a clamp at 4380 bytes
+ * rather than use a multiplier in the relevant range.
+ */
__u32 tcp_init_cwnd(struct tcp_sock *tp, struct dst_entry *dst)
{
__u32 cwnd = (dst ? dst_metric(dst, RTAX_INITCWND) : 0);