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Date:   Fri, 12 Aug 2022 16:55:16 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Cong Wang <xiyou.wangcong@gmail.com>
Cc:     netdev@vger.kernel.org, bpf@vger.kernel.org,
        Cong Wang <cong.wang@bytedance.com>,
        Eric Dumazet <edumazet@google.com>,
        John Fastabend <john.fastabend@gmail.com>,
        Jakub Sitnicki <jakub@cloudflare.com>
Subject: Re: [Patch net v2 3/4] tcp: refactor tcp_read_skb() a bit
Message-ID: <20220812165516.45432ef0@kernel.org>
In-Reply-To: <20220808033106.130263-4-xiyou.wangcong@gmail.com>
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        <20220808033106.130263-4-xiyou.wangcong@gmail.com>
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On Sun,  7 Aug 2022 20:31:05 -0700 Cong Wang wrote:
> From: Cong Wang <cong.wang@bytedance.com>
> 
> As tcp_read_skb() only reads one skb at a time, the while loop is
> unnecessary, we can turn it into an if. This also simplifies the
> code logic.

I think Eric is AFK so we should just apply these, they LGTM.
One minor nit below.

> --- a/net/ipv4/tcp.c
> +++ b/net/ipv4/tcp.c
> @@ -1761,27 +1761,18 @@ int tcp_read_skb(struct sock *sk, skb_read_actor_t recv_actor)
>  	if (sk->sk_state == TCP_LISTEN)
>  		return -ENOTCONN;
>  
> -	while ((skb = tcp_recv_skb(sk, seq, &offset)) != NULL) {
> -		int used;
> -
> +	skb = tcp_recv_skb(sk, seq, &offset);
> +	if (skb) {

if (!skb)
	return 0;

?