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Date:   Sun, 11 Oct 2020 15:41:50 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Heiner Kallweit <hkallweit1@gmail.com>
Cc:     David Miller <davem@davemloft.net>,
        =?UTF-8?B?QmrDuHJu?= Mork <bjorn@mork.no>,
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        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>,
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        Vladimir Oltean <olteanv@gmail.com>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Johannes Berg <johannes@sipsolutions.net>,
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Subject: Re: [PATCH net-next 00/12] net: add and use function
 dev_fetch_sw_netstats for fetching pcpu_sw_netstats
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On Mon, 12 Oct 2020 00:29:52 +0200 Heiner Kallweit wrote:
> 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.

struct net_device::stats? That's not per-cpu.
Or do you mean struct net_device::tx_dropped? That'd work nicely.