From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 1/2 v3] xps: Improvements in TX queue selection
Date: Sun, 24 Oct 2010 15:32:06 -0700 (PDT)
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From: Tom Herbert <therbert@google.com>
Date: Thu, 21 Oct 2010 13:17:08 -0700 (PDT)

> @@ -822,8 +822,10 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
>  							   &md5);
>  	tcp_header_size = tcp_options_size + sizeof(struct tcphdr);
>  
> -	if (tcp_packets_in_flight(tp) == 0)
> +	if (tcp_packets_in_flight(tp) == 0) {
>  		tcp_ca_event(sk, CA_EVENT_TX_START);
> +		skb->ooo_okay = 1;
> +	}
>  

You'll need to clear this flag the moment the first transmit of
this packet happens, otherwise OOO won't be handled correctly in
the event that fast retransmit is necessary later.