[dpdk-dev] [dpdk-stable] [PATCH] net/i40e: fix packet count for PF

[Ferruh Yigit]

On 8/20/2017 9:05 PM, Qi Zhang wrote:
> Previously, for PF statistics we use VSI register for packet count
> but use port's register for packet bytes, that cause inconsistent
> situation of PF statistics when some VF is active,  since it will
> cover VF's packet bytes but not packet count.
> The patch will take port register for PF packet count back, but still
> exclude main vsi's discard packet count.
> Just like pervious fix, its still not perfect,(since RX packet number
> is over counted when there is VF discard packet) but seems it make the
> overall better).

What does Linux do for stats calculation?
I believe it is good to be consistent with it.

> 
> Fixes: 9aace75fc82e ("i40e: fix statistics")
> Cc: stable at dpdk.org
> 
> Signed-off-by: Qi Zhang <qi.z.zhang at intel.com>
> ---
>  drivers/net/i40e/i40e_ethdev.c | 13 +++++++------
>  1 file changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
> index 5f26e24..63acbb8 100644
> --- a/drivers/net/i40e/i40e_ethdev.c
> +++ b/drivers/net/i40e/i40e_ethdev.c
> @@ -2664,13 +2664,14 @@ i40e_dev_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *stats)
>  	/* call read registers - updates values, now write them to struct */
>  	i40e_read_stats_registers(pf, hw);
>  
> -	stats->ipackets = pf->main_vsi->eth_stats.rx_unicast +
> -			pf->main_vsi->eth_stats.rx_multicast +
> -			pf->main_vsi->eth_stats.rx_broadcast -
> +	stats->ipackets = ns->eth.rx_unicast +
> +			ns->eth.rx_multicast +
> +			ns->eth.rx_broadcast -
> +			ns->eth.rx_discards -
>  			pf->main_vsi->eth_stats.rx_discards;

Both port rx_discards and PF rx_discards excluded, is this intentional?
Won't this cause double exclusion of some rx_discards packets?

> -	stats->opackets = pf->main_vsi->eth_stats.tx_unicast +
> -			pf->main_vsi->eth_stats.tx_multicast +
> -			pf->main_vsi->eth_stats.tx_broadcast;
> +	stats->opackets = ns->eth.tx_unicast +
> +			ns->eth.tx_multicast +
> +			ns->eth.tx_broadcast;
>  	stats->ibytes   = ns->eth.rx_bytes;
>  	stats->obytes   = ns->eth.tx_bytes;
>  	stats->oerrors  = ns->eth.tx_errors +
>