On Sun, 2017-10-22 at 09:49 -0700, Eric Dumazet wrote: > Here is the test I cooked. > > Note that it actually passes just fine, do I am wondering if your patch > is needed after all.. >
Oh this is because tcp_mstamp_refresh() is called from tcp_write_xmit() and tcp_write_xmit() is directly called from tcp_tsq_handler() So it looks your patch has no observable effect. (Even with usec TS as we use here at Google, it has no effect since TCP stack does not consider RTT samples being valid if skb was ever retransmitted)
