Re: [dpdk-dev] [PATCH 2/2] net/cxgbe: remove queue stats from basic stats

[Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>]

Hi Rahul,

On 7/1/21 6:26 PM, Rahul Lakkireddy wrote:
> Hi Andrew,
> 
> On Thursday, July 07/01/21, 2021 at 17:50:19 +0300, Andrew Rybchenko wrote:
>> On 6/3/21 6:30 PM, Rahul Lakkireddy wrote:
>>> Remove queue stats from basic stats because they're now available
>>> via xstats API. Also remove RTE_ETH_DEV_AUTOFILL_QUEUE_XSTATS flag.
>>>
>>> Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
>>> ---
>>>  drivers/net/cxgbe/cxgbe_ethdev.c | 18 +++---------------
>>>  1 file changed, 3 insertions(+), 15 deletions(-)
>>>
>>> diff --git a/drivers/net/cxgbe/cxgbe_ethdev.c b/drivers/net/cxgbe/cxgbe_ethdev.c
>>> index 8dee3fc3b6..141a2de808 100644
>>> --- a/drivers/net/cxgbe/cxgbe_ethdev.c
>>> +++ b/drivers/net/cxgbe/cxgbe_ethdev.c
>>> @@ -747,22 +747,12 @@ static int cxgbe_dev_stats_get(struct rte_eth_dev *eth_dev,
>>>  	eth_stats->oerrors  = ps.tx_error_frames;
>>>  
>>>  	for (i = 0; i < pi->n_rx_qsets; i++) {
>>> -		struct sge_eth_rxq *rxq =
>>> -			&s->ethrxq[pi->first_rxqset + i];
>>> +		struct sge_eth_rxq *rxq = &s->ethrxq[pi->first_rxqset + i];
>>>  
>>> -		eth_stats->q_ipackets[i] = rxq->stats.pkts;
>>> -		eth_stats->q_ibytes[i] = rxq->stats.rx_bytes;
>>> -		eth_stats->ipackets += eth_stats->q_ipackets[i];
>>> -		eth_stats->ibytes += eth_stats->q_ibytes[i];
>>> +		eth_stats->ipackets += rxq->stats.pkts;
>>> +		eth_stats->ibytes += rxq->stats.rx_bytes;
>>>  	}
>>>  
>>> -	for (i = 0; i < pi->n_tx_qsets; i++) {
>>> -		struct sge_eth_txq *txq =
>>> -			&s->ethtxq[pi->first_txqset + i];
>>> -
>>> -		eth_stats->q_opackets[i] = txq->stats.pkts;
>>> -		eth_stats->q_obytes[i] = txq->stats.tx_bytes;
>>> -	}
>>>  	return 0;
>>>  }
>>>  
>>> @@ -1697,8 +1687,6 @@ static int eth_cxgbe_dev_init(struct rte_eth_dev *eth_dev)
>>>  		return 0;
>>>  	}
>>>  
>>> -	eth_dev->data->dev_flags |= RTE_ETH_DEV_AUTOFILL_QUEUE_XSTATS;
>>> -
>>>  	snprintf(name, sizeof(name), "cxgbeadapter%d", eth_dev->data->port_id);
>>>  	adapter = rte_zmalloc(name, sizeof(*adapter), 0);
>>>  	if (!adapter)
>>>
>>
>> As I understand it is correct to remove
>> RTE_ETH_DEV_AUTOFILL_QUEUE_XSTATS to avoid duplication of per-queue
>> stats in xstats. But I don't understand why per-queue
>> stats are removed from basic stats. It still makes sense and
>> useful. Am I missing something?
> 
> The per-queue stats are being removed from basic stats here because
> these will be removed from rte_eth_stats, as per the below deprecation
> notice.
> 
> * ethdev: Queue specific stats fields will be removed from ``struct rte_eth_stats``.
>   Mentioned fields are: ``q_ipackets``, ``q_opackets``, ``q_ibytes``, ``q_obytes``,
>   ``q_errors``.
>   Instead queue stats will be received via xstats API. Current method support
>   will be limited to maximum 256 queues.
>   Also compile time flag ``RTE_ETHDEV_QUEUE_STAT_CNTRS`` will be removed.

Thanks a lot. It is bad that I've lost it from my view.
Clear now.

Andrew.