From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cong Wang <xiyou.wangcong@gmail.com>
Subject: Re: [PATCH v5 2/2] sock: Move the socket inuse to namespace.
Date: Thu, 7 Dec 2017 13:28:43 -0800
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Cc: Tonghao Zhang <xiangxia.m.yue@gmail.com>,
        David Miller <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Willem de Bruijn <willemb@google.com>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Thu, Dec 7, 2017 at 9:20 AM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> On Thu, 2017-12-07 at 08:45 -0800, Tonghao Zhang wrote:
>> In some case, we want to know how many sockets are in use in
>> different _net_ namespaces. It's a key resource metric.
>>
>
> ...
>
>> +static void sock_inuse_add(struct net *net, int val)
>> +{
>> +     if (net->core.prot_inuse)
>> +             this_cpu_add(*net->core.sock_inuse, val);
>> +}
>
> This is very confusing.
>
> Why testing net->core.prot_inuse for NULL is needed at all ?
>
> Why not testing net->core.sock_inuse instead ?

I bet that is copy-n-paste error given that sock_inuse_exit_net()
has a similar typo.