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Subject: Re: [PATCH net-next] tcp: minor optimization for calculating
 packets_out in tcp connect
To:     Yafang Shao <laoar.shao@gmail.com>, edumazet@google.com,
        davem@davemloft.net
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org
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From:   Eric Dumazet <eric.dumazet@gmail.com>
Message-ID: <48971720-96e1-a48f-a1f5-3a96aa3fae7a@gmail.com>
Date:   Sat, 15 Dec 2018 04:59:00 -0800
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On 12/15/2018 01:33 AM, Yafang Shao wrote:
> When we building a syn packet, the tcp_skb_pcount(skb) is always 1,
> which is set in tcp_init_nondata_skb().
> Regarding the syn_data, it is set through
> memcpy(syn_data->cb, syn->cb, sizeof(syn->cb)),
> which is always 1 as well.
> 
> So we don't need to use tcp_skb_pcount(skb), that could give us a
> little improvement.
>

I dunno, I find current code more self-documented.

This is not fast path, so I would suggest we keep it.

Thanks.