Re: 2.6.10 TCP troubles -- suggested patch

[Stephen Hemminger <shemminger@xxxxxxxx>]

Please try this patch, based on Alexey's suggestion:

> That's one quick and simple idea: set PSH on each tso segment.
> Seems, it is always good. Hardware will preserve it only on the last skb and
> everyone will be happy.

# This is a BitKeeper generated diff -Nru style patch.
#
# ChangeSet
#   2005/02/09 11:00:57-08:00 shemminger@xxxxxxxxxx 
#   Always set PUSH on TSO multi-segment frames
#   to workaround bugs in MacOSX
# 
# net/ipv4/tcp_output.c
#   2005/02/09 11:00:44-08:00 shemminger@xxxxxxxxxx +8 -0
#   Always set PUSH on TSO multi-segment frames
#   to workaround bugs in MacOSX
# 
diff -Nru a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
--- a/net/ipv4/tcp_output.c     2005-02-09 11:01:12 -08:00
+++ b/net/ipv4/tcp_output.c     2005-02-09 11:01:12 -08:00
@@ -754,6 +754,14 @@
                                        break;
                        }
 
+                       /* Force push to be on for any large TSO frames
+                        * to workaround problems with busted implementations
+                        * like MacOSX that hold off delivery of data until
+                        * push.
+                        */
+                       if (tcp_skb_pcount(skb) > 1)
+                           TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
+
                        TCP_SKB_CB(skb)->when = tcp_time_stamp;
                        if (tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC)))
                                break;