From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexei Starovoitov <ast@fb.com>
Subject: Re: [net-next PATCH 07/10] bpf: add access to sock fields and pkt
 data from sk_skb programs
Date: Wed, 16 Aug 2017 22:42:12 -0700
Message-ID: <f6bdacf6-7a8c-226f-5a22-f14bebac356b@fb.com>
References: <20170816052338.15445.83732.stgit@john-Precision-Tower-5810>
 <20170816053309.15445.97681.stgit@john-Precision-Tower-5810>
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Cc: <tgraf@suug.ch>, <netdev@vger.kernel.org>, <tom@herbertland.com>
To: John Fastabend <john.fastabend@gmail.com>, <davem@davemloft.net>,
        <daniel@iogearbox.net>
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On 8/15/17 10:33 PM, John Fastabend wrote:
> +static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
> +			   const struct bpf_prog *prog)
> +{
> +	struct bpf_insn *insn = insn_buf;
> +
> +	if (!direct_write)
> +		return 0;
> +
> +	/* if (!skb->cloned)
> +	 *       goto start;
> +	 *
> +	 * (Fast-path, otherwise approximation that we might be
> +	 *  a clone, do the rest in helper.)
> +	 */

iirc we're doing something similar in other prologue generator?
can be consolidated?