From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jakub Kicinski <jakub.kicinski@netronome.com>
Subject: Re: [PATCH net-next 0/3] nfp: flower: speed up stats update loop
Date: Wed, 10 Oct 2018 08:08:14 -0700
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        <CAJ3xEMi4p=XP9fbfjPxgSdd-8c+d++v3wdAUZihCwtf46+LODA@mail.gmail.com>
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Cc: David Miller <davem@davemloft.net>,
        Linux Netdev List <netdev@vger.kernel.org>,
        oss-drivers@netronome.com
To: Or Gerlitz <gerlitz.or@gmail.com>
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On Wed, 10 Oct 2018 16:40:56 +0300, Or Gerlitz wrote:
> On Tue, Oct 9, 2018 at 4:58 AM Jakub Kicinski
> <jakub.kicinski@netronome.com> wrote:
> 
> > Given that our statistic IDs are already array indices, and considering
> > each statistic is only 24B in size, we decided to forego the use  
> 
> 8B packet + 8B bytes --> 16B -- does your FW/HW provide last use? how do
> you express this lastuse value in host jiffies?

24B is the size of the structure we keep in the driver, which costs
host memory.  The message from FW contains this:

struct nfp_fl_stats_frame {
	__be32 stats_con_id;
	__be32 pkt_count;
	__be64 byte_count;
	__be64 stats_cookie;
};