Re: [dpdk-dev] [PATCH v3] net/nfb: new netcope driver

[David Marchand <david.marchand@redhat.com>]

On Fri, Mar 1, 2019 at 3:38 PM Rastislav Cernay <cernay@netcope.com> wrote:

> diff --git a/drivers/net/nfb/nfb_stats.c b/drivers/net/nfb/nfb_stats.c
> new file mode 100644
> index 0000000..ffc27a5
> --- /dev/null
> +++ b/drivers/net/nfb/nfb_stats.c
> @@ -0,0 +1,78 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright(c) 2018 Cesnet
> + * Copyright(c) 2018 Netcope Technologies, a.s. <info@netcope.com>
> + * All rights reserved.
> + */
> +
> +#include "nfb_stats.h"
> +#include "nfb.h"
> +
> +int
> +nfb_eth_stats_get(struct rte_eth_dev *dev,
> +       struct rte_eth_stats *stats)
> +{
> +       uint16_t i;
> +       uint16_t nb_rx = dev->data->nb_rx_queues;
> +       uint16_t nb_tx = dev->data->nb_tx_queues;
> +       uint64_t rx_total = 0;
> +       uint64_t tx_total = 0;
> +       uint64_t tx_err_total = 0;
> +       uint64_t rx_total_bytes = 0;
> +       uint64_t tx_total_bytes = 0;
> +
> +       struct ndp_rx_queue *rx_queue = *((struct ndp_rx_queue **)
> +               dev->data->rx_queues);
> +       struct ndp_tx_queue *tx_queue = *((struct ndp_tx_queue **)
> +               dev->data->tx_queues);
> +
> +       for (i = 0; i < nb_rx; i++) {
> +               if (i < RTE_ETHDEV_QUEUE_STAT_CNTRS) {
> +                       stats->q_ipackets[i] = rx_queue[i].rx_pkts;
> +                       stats->q_ibytes[i] = rx_queue[i].rx_bytes;
> +               }
> +               rx_total += stats->q_ipackets[i];
> +               rx_total_bytes += stats->q_ibytes[i];
> +       }
>

What is the point of adding when i >= RTE_ETHDEV_QUEUE_STAT_CNTRS ?
Hopefully, ethdev passes a zero'd structure, but still I find it confusing.



> +
> +       for (i = 0; i < nb_tx; i++) {
> +               if (i < RTE_ETHDEV_QUEUE_STAT_CNTRS) {
> +                       stats->q_opackets[i] = tx_queue[i].tx_pkts;
> +                       stats->q_obytes[i] = tx_queue[i].tx_bytes;
> +                       stats->q_errors[i] = tx_queue[i].err_pkts;
> +               }
> +               tx_total += stats->q_opackets[i];
> +               tx_total_bytes += stats->q_obytes[i];
> +               tx_err_total += stats->q_errors[i];
> +       }
>

Idem.
Besides, q_errors[] is for reception errors.

+
> +       stats->ipackets = rx_total;
> +       stats->opackets = tx_total;
> +       stats->ibytes = rx_total_bytes;
> +       stats->obytes = tx_total_bytes;
> +       stats->oerrors = tx_err_total;
> +       return 0;
> +}
>
>
-- 
David Marchand