Date:   Tue, 30 Nov 2021 09:04:49 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Alexander Lobakin <alexandr.lobakin@intel.com>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Jesse Brandeburg <jesse.brandeburg@intel.com>,
        Michal Swiatkowski <michal.swiatkowski@linux.intel.com>,
        Maciej Fijalkowski <maciej.fijalkowski@intel.com>,
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        Claudiu Manoil <claudiu.manoil@nxp.com>,
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Subject: Re: [PATCH v2 net-next 00/26] net: introduce and use generic XDP
 stats
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On Tue, 30 Nov 2021 17:34:54 +0100 Alexander Lobakin wrote:
> > Another thought on this patch: with individual attributes you could save
> > some overhead by not sending 0 counters to userspace. e.g., define a
> > helper that does:  
> 
> I know about ETHTOOL_STAT_NOT_SET, but RTNL xstats doesn't use this,
> does it?

Not sure if you're asking me or Dave but no, to my knowledge RTNL does
not use such semantics today. But the reason is mostly because there
weren't many driver stats added there. Knowing if an error counter is
not supported or supporter and 0 is important for monitoring. Even if
XDP stats don't have a counter which may not be supported today it's
not a good precedent to make IMO.