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From:   Eric Dumazet <edumazet@google.com>
Date:   Thu, 7 May 2020 06:49:46 -0700
Message-ID: <CANn89iLiCh-LDw9WsB=3Wm=V-Ey80JRrC8yf8fsy=vbVc9FuPQ@mail.gmail.com>
Subject: Re: [PATCH] net: optimize cmpxchg in ip_idents_reserve
To:     Shaokun Zhang <zhangshaokun@hisilicon.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Eric Dumazet <eric.dumazet@gmail.com>,
        Arvind Sankar <nivedita@alum.mit.edu>,
        David Miller <davem@davemloft.net>,
        netdev <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, jinyuqi@huawei.com,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        guoyang2@huawei.com, Will Deacon <will@kernel.org>
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On Thu, May 7, 2020 at 2:12 AM Shaokun Zhang <zhangshaokun@hisilicon.com> wrote:
>
> Hi Peter/Eric,
>
> Shall we use atomic_add_return() unconditionally and add some comments? Or I missed
> something.
>


Yes. A big fat comment, because I do not want yet another bogus
complaint from someone playing with a buggy UBSAN.