Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [PATCH net-next 00/12] net: add and use function
 dev_fetch_sw_netstats for fetching pcpu_sw_netstats
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     David Miller <davem@davemloft.net>,
        =?UTF-8?Q?Bj=c3=b8rn_Mork?= <bjorn@mork.no>,
        Oliver Neukum <oneukum@suse.com>,
        Igor Mitsyanko <imitsyanko@quantenna.com>,
        Sergey Matyukevich <geomatsi@gmail.com>,
        Kalle Valo <kvalo@codeaurora.org>,
        Roopa Prabhu <roopa@nvidia.com>,
        Nikolay Aleksandrov <nikolay@nvidia.com>,
        Andrew Lunn <andrew@lunn.ch>,
        Vivien Didelot <vivien.didelot@gmail.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Johannes Berg <johannes@sipsolutions.net>,
        Pravin B Shelar <pshelar@ovn.org>,
        Steffen Klassert <steffen.klassert@secunet.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        linux-rdma@vger.kernel.org,
        Linux USB Mailing List <linux-usb@vger.kernel.org>,
        linux-wireless <linux-wireless@vger.kernel.org>,
        bridge@lists.linux-foundation.org
References: <a46f539e-a54d-7e92-0372-cd96bb280729@gmail.com>
 <20201011151030.05ad88dd@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
From:   Heiner Kallweit <hkallweit1@gmail.com>
Message-ID: <1f1dceab-bab0-ff9e-dae6-ed35be504a9c@gmail.com>
Date:   Mon, 12 Oct 2020 00:29:52 +0200
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101
 Thunderbird/68.12.1
MIME-Version: 1.0
In-Reply-To: <20201011151030.05ad88dd@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 12.10.2020 00:10, Jakub Kicinski wrote:
> On Sun, 11 Oct 2020 21:34:58 +0200 Heiner Kallweit wrote:
>> In several places the same code is used to populate rtnl_link_stats64
>> fields with data from pcpu_sw_netstats. Therefore factor out this code
>> to a new function dev_fetch_sw_netstats().
> 
> FWIW probably fine to convert nfp_repr_get_host_stats64() as well, just
> take out the drop counter and make it a separate atomic. If you're up
> for that.
> 
Looking at nfp_repr_get_host_stats64() I'm not sure why the authors
decided to add a 64bit tx drop counter, struct net_device_stats has
an unsigned long tx_dropped counter already. And that the number of
dropped tx packets exceeds 32bit (on 32bit systems) seems not very
likely.