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Date:   Fri, 10 Jan 2020 07:50:56 -0800
From:   Stephen Hemminger <stephen@networkplumber.org>
To:     Niu Xilei <niu_xilei@163.com>
Cc:     davem@davemloft.net, tglx@linutronix.de, fw@strlen.de,
        peterz@infradead.org, pabeni@redhat.com, anshuman.khandual@arm.com,
        linyunsheng@huawei.com, bigeasy@linutronix.de,
        jonathan.lemon@gmail.com, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH]     pktgen: create packet use  IPv6 source address
 between src6_min and src6_max.
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In-Reply-To: <20200110102842.13585-1-niu_xilei@163.com>
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On Fri, 10 Jan 2020 18:28:42 +0800
Niu Xilei <niu_xilei@163.com> wrote:

> +/* Kernel not implement __int128's divide and modulo operator. Implement these
> + * operation use shift-subtract division algorithm  adpater from
> + * https://chromium.googlesource.com/chromium/src/third_party/+/master/abseil-cpp/absl/numeric/int128.cc */

Some rewording of this comment is necessary to fix the English grammar.
And Linux style is not to put comment closing on same line.

Something like:

/* The Linux kernel does not implement 128 bit divide and modulus operations.
 * Implement these operations using shift-subtract division algorithm
 * from Chrome.
 * https://chromium.googlesource.com/chromium/src/third_party/+/master/abseil-cpp/absl/numeric/int128.cc
 */

Also, the int128 code you referenced is Apache licensed (not GPL-v2 like kernel).

For div128_u128 the function should be static to avoid name conflicts.

The declarations need to be in reverse christmas tree order as well.

It does seem a bit like overkill since doing source address over a 64 bit
range should be more than enough for any test in this decade.