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Date:   Mon, 16 May 2022 08:47:42 -0600
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Subject: Re: [PATCH net-next v3 00/10] UDP/IPv6 refactoring
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To:     Paolo Abeni <pabeni@redhat.com>,
        Pavel Begunkov <asml.silence@gmail.com>,
        netdev@vger.kernel.org, "David S . Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>
Cc:     Eric Dumazet <edumazet@google.com>, linux-kernel@vger.kernel.org
References: <cover.1652368648.git.asml.silence@gmail.com>
 <b9025eb4d8a1efefbcd04013cbe8e55e98ef66e1.camel@redhat.com>
From:   David Ahern <dsahern@kernel.org>
In-Reply-To: <b9025eb4d8a1efefbcd04013cbe8e55e98ef66e1.camel@redhat.com>
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On 5/16/22 7:48 AM, Paolo Abeni wrote:
> Hello,
> 
> On Fri, 2022-05-13 at 16:26 +0100, Pavel Begunkov wrote:
>> Refactor UDP/IPv6 and especially udpv6_sendmsg() paths. The end result looks
>> cleaner than it was before and the series also removes a bunch of instructions
>> and other overhead from the hot path positively affecting performance.
>>
>> Testing over dummy netdev with 16 byte packets yields 2240481 tx/s,
>> comparing to 2203417 tx/s previously, which is around +1.6%
> 
> I personally feel that some patches in this series have a relevant
> chance of introducing functional regressions and e.g. syzbot will not
> help to catch them. That risk is IMHO relevant considered that the
> performance gain here looks quite limited.
> 
> There are a few individual changes that IMHO looks like nice cleanup
> e.g. patch 5, 6, 8, 9 and possibly even patch 1.
> 
> I suggest to reduce the patchset scope to them.
> 

I agree with that sentiment. The set also needs testcases that captures
the various permutations.