X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=net%2Fipv4%2Ftcp_output.c;h=a627616314baf0b137a075ce0fb340a0d20ba475;hb=fc8717baa8f52dd8d1b90df9008300ef3ec794ed;hp=ed750f9ceb07caed9ed5479740e664c6a319bc8f;hpb=dd07a8db7283f52f347aee468007556944b5b393;p=linux-2.6

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index ed750f9ceb..a627616314 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -255,7 +255,7 @@ static u16 tcp_select_window(struct sock *sk)
 		 *
 		 * Relax Will Robinson.
 		 */
-		new_win = cur_win;
+		new_win = ALIGN(cur_win, 1 << tp->rx_opt.rcv_wscale);
 	}
 	tp->rcv_wnd = new_win;
 	tp->rcv_wup = tp->rcv_nxt;
@@ -998,7 +998,7 @@ unsigned int tcp_current_mss(struct sock *sk, int large_allowed)
 	xmit_size_goal = mss_now;
 
 	if (doing_tso) {
-		xmit_size_goal = (65535 -
+		xmit_size_goal = ((sk->sk_gso_max_size - 1) -
 				  inet_csk(sk)->icsk_af_ops->net_header_len -
 				  inet_csk(sk)->icsk_ext_hdr_len -
 				  tp->tcp_header_len);
@@ -1035,6 +1035,13 @@ static void tcp_cwnd_validate(struct sock *sk)
  * introducing MSS oddities to segment boundaries. In rare cases where
  * mss_now != mss_cache, we will request caller to create a small skb
  * per input skb which could be mostly avoided here (if desired).
+ *
+ * We explicitly want to create a request for splitting write queue tail
+ * to a small skb for Nagle purposes while avoiding unnecessary modulos,
+ * thus all the complexity (cwnd_len is always MSS multiple which we
+ * return whenever allowed by the other factors). Basically we need the
+ * modulo only when the receiver window alone is the limiting factor or
+ * when we would be allowed to send the split-due-to-Nagle skb fully.
  */
 static unsigned int tcp_mss_split_point(struct sock *sk, struct sk_buff *skb,
 					unsigned int mss_now, unsigned int cwnd)
@@ -1048,10 +1055,11 @@ static unsigned int tcp_mss_split_point(struct sock *sk, struct sk_buff *skb,
 	if (likely(cwnd_len <= window && skb != tcp_write_queue_tail(sk)))
 		return cwnd_len;
 
-	if (skb == tcp_write_queue_tail(sk) && cwnd_len <= skb->len)
+	needed = min(skb->len, window);
+
+	if (skb == tcp_write_queue_tail(sk) && cwnd_len <= needed)
 		return cwnd_len;
 
-	needed = min(skb->len, window);
 	return needed - needed % mss_now;
 }
 
@@ -1274,7 +1282,7 @@ static int tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
 	limit = min(send_win, cong_win);
 
 	/* If a full-sized TSO skb can be sent, do it. */
-	if (limit >= 65536)
+	if (limit >= sk->sk_gso_max_size)
 		goto send_now;
 
 	if (sysctl_tcp_tso_win_divisor) {
@@ -2560,6 +2568,7 @@ void tcp_send_probe0(struct sock *sk)
 	}
 }
 
+EXPORT_SYMBOL(tcp_select_initial_window);
 EXPORT_SYMBOL(tcp_connect);
 EXPORT_SYMBOL(tcp_make_synack);
 EXPORT_SYMBOL(tcp_simple_retransmit);