From: Octavian Purdila <redacted>
Date: Thu, 27 Aug 2009 02:08:31 +0300

This fixes a temporary performance issue we noticed in back to back
TSO - LRO tests when such tests are run within five minutes after
boot.

The TSval field of TCP packets is filled in based on the current
jiffie, which is initialized at -300*HZ. That means that in 5 minutes
after reboot it will wrap to zero.

RFC1323 says we absolutely must ignore zero TSecr values.

It is a bug that the stack emits a zero value when it means to give a
real TSecr value that will be used.

Probably we can do something like emit '1' when we would emit '0'
based upon jiffies.

And this would be an improvement from now in that having a off-by-one
TSecr in this situation is better than emitting one which we can
guarentee will be ignored.