Re: [PATCH net-next v3 2/3] bnxt: count packets discarded because of netpoll

On Thu, 26 Aug 2021 14:17:45 -0700 Michael Chan wrote:

On Thu, Aug 26, 2021 at 12:18 PM Jakub Kicinski [off-list ref] wrote:

quoted

On Thu, 26 Aug 2021 11:43:58 -0700 Michael Chan wrote:  

quoted

Can we just add these rx_netpoll_discards counters directly to
stats->rx_dropped?  It looks simpler if we do it that way, right?  

To make sure - are you saying that instead of adding

        struct bnxt_sw_stats    sw_stats_prev;

we should accumulate in net_stats_prev->rx_dropped, and have
the ethtool counter only report the discards since last down/up?

Or to use the atomic counter on the netdev and never report
in ethtool (since after patch 3 rx_dropped is a mix of reasons)?  

OK.  I've reviewed the patch again and you need to keep the previous
netpoll discard counter so that you can report the total current and
previous netpoll discard counter under ethtool -S.

My suggestion would lump the previous netpoll discard counter into the
previous rx_dropped counter and you can only report the current
netpoll discard counter under ethtool -S.  But note that all the ring
related counters we currently report are current counters and do not
include old counters before the last reset.

Oh, [rt]x_total_discard_pkts are also just a sum of current counters?
I missed that. In that case if netpoll discards reset it's not a big
deal, I'll respin the patch tomorrow. Let me also rename from
rx_netpoll_discards to rx_total_netpoll_discards, adding the "total_"
will hopefully signal the similarity of semantics?