RE: [Patch v2] net/netvsc: report correct stats values

[Long Li <longli@microsoft.com>]

> Subject: Re: [Patch v2] net/netvsc: report correct stats values
> 
> On 5/3/2022 7:18 PM, Long Li wrote:
> >> Subject: Re: [Patch v2] net/netvsc: report correct stats values
> >>
> >> On Tue, 26 Apr 2022 22:56:14 +0100
> >> Ferruh Yigit <ferruh.yigit@xilinx.com> wrote:
> >>
> >>>>    		if (i < RTE_ETHDEV_QUEUE_STAT_CNTRS) {
> >>>> -			stats->q_opackets[i] = txq->stats.packets;
> >>>> -			stats->q_obytes[i] = txq->stats.bytes;
> >>>> +			stats->q_opackets[i] += txq->stats.packets;
> >>>> +			stats->q_obytes[i] += txq->stats.bytes;
> >>>
> >>> This is per queue stats, 'stats->q_opackets[i]', in next iteration
> >>> of the loop, 'i' will be increased and 'txq' will be updated, so as
> >>> far as I can see the above change has no affect.
> >>
> >> Agree, that is why it was just assignment originally.
> >
> > The condition here is a little different. NETVSC is a master device with
> another PMD running as a slave. When reporting stats values, it needs to add
> the values from the slave PMD. The original code just overwrites the values
> from its slave PMD.
> 
> Where the initial values are coming from, 'hn_vf_stats_get()'?
> 
> If 'hn_vf_stats_get()' fills the stats, what are the values kept in 'txq->stats.*'
> in above updated loop?

Yes, hn_vf_stats_get() fills in the stats from the slave PMD. txq->stats values are from the master PMD. Those values are different and accounted separated from the values from the slave PMD.