tcp: deferring in middle of queue makes very little sense

If skb can be sent right away, we certainly should do that
if it's in the middle of the queue because it won't get
more data into it.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 2471cd4f66db7f99a1855e7837f94b9cb4a3ed3c..fa3c81aa4e6af23203892d60ad40ebe7be3a5100 100644 (file)
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1356,6 +1356,10 @@ static int tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
        if (limit >= sk->sk_gso_max_size)
                goto send_now;
 
+       /* Middle in queue won't get any more data, full sendable already? */
+       if ((skb != tcp_write_queue_tail(sk)) && (limit >= skb->len))
+               goto send_now;
+
        if (sysctl_tcp_tso_win_divisor) {
                u32 chunk = min(tp->snd_wnd, tp->snd_cwnd * tp->mss_cache);