From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yuchung Cheng <ycheng@google.com>
Subject: Re: [PATCH net-next 1/3] tcp: remove hdrlen argument from tcp_queue_rcv()
Date: Wed, 21 Nov 2018 14:41:14 -0800
Message-ID: <CAK6E8=cWKNt0asFejZ+d9gRH4NvBqW5gSQfn1fkLvNearSm_Ug@mail.gmail.com>
References: <20181121175240.6075-1-edumazet@google.com> <20181121175240.6075-2-edumazet@google.com>
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Cc: "David S . Miller" <davem@davemloft.net>,
        netdev <netdev@vger.kernel.org>,
        Jean-Louis Dupond <jean-louis@dupond.be>,
        Neal Cardwell <ncardwell@google.com>,
        Eric Dumazet <eric.dumazet@gmail.com>
To: Eric Dumazet <edumazet@google.com>
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On Wed, Nov 21, 2018 at 9:52 AM, Eric Dumazet <edumazet@google.com> wrote:
> Only one caller needs to pull TCP headers, so lets
> move __skb_pull() to the caller side.
>
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
Acked-by: Yuchung Cheng <ycheng@google.com>

>  net/ipv4/tcp_input.c | 13 ++++++-------
>  1 file changed, 6 insertions(+), 7 deletions(-)
>
> diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
> index edaaebfbcd4693ef6689f3f4c71733b3888c7c2c..e0ad7d3825b5945049c099171ce36e5c8bb9ba99 100644
> --- a/net/ipv4/tcp_input.c
> +++ b/net/ipv4/tcp_input.c
> @@ -4602,13 +4602,12 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb)
>         }
>  }
>
> -static int __must_check tcp_queue_rcv(struct sock *sk, struct sk_buff *skb, int hdrlen,
> -                 bool *fragstolen)
> +static int __must_check tcp_queue_rcv(struct sock *sk, struct sk_buff *skb,
> +                                     bool *fragstolen)
>  {
>         int eaten;
>         struct sk_buff *tail = skb_peek_tail(&sk->sk_receive_queue);
>
> -       __skb_pull(skb, hdrlen);
>         eaten = (tail &&
>                  tcp_try_coalesce(sk, tail,
>                                   skb, fragstolen)) ? 1 : 0;
> @@ -4659,7 +4658,7 @@ int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size)
>         TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq + size;
>         TCP_SKB_CB(skb)->ack_seq = tcp_sk(sk)->snd_una - 1;
>
> -       if (tcp_queue_rcv(sk, skb, 0, &fragstolen)) {
> +       if (tcp_queue_rcv(sk, skb, &fragstolen)) {
>                 WARN_ON_ONCE(fragstolen); /* should not happen */
>                 __kfree_skb(skb);
>         }
> @@ -4719,7 +4718,7 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
>                         goto drop;
>                 }
>
> -               eaten = tcp_queue_rcv(sk, skb, 0, &fragstolen);
> +               eaten = tcp_queue_rcv(sk, skb, &fragstolen);
>                 if (skb->len)
>                         tcp_event_data_recv(sk, skb);
>                 if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
> @@ -5585,8 +5584,8 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb)
>                         NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHPHITS);
>
>                         /* Bulk data transfer: receiver */
> -                       eaten = tcp_queue_rcv(sk, skb, tcp_header_len,
> -                                             &fragstolen);
> +                       __skb_pull(skb, tcp_header_len);
> +                       eaten = tcp_queue_rcv(sk, skb, &fragstolen);
>
>                         tcp_event_data_recv(sk, skb);
>
> --
> 2.19.1.1215.g8438c0b245-goog
>