On Fri, Jan 12, 2024 at 8:36 PM Ferruh Yigit <ferruh.yigit@amd.com> wrote:

On 12/22/2023 3:39 PM, Rushil Gupta wrote:
> Read from shared region to retrieve imissed statistics for GQ from device.
> Tested using `show port xstats <port-id>` in interactive mode.
> This metric can be triggered by using queues > cores.
>

Looks good but please check following comments:

Checkpatch gives warning on the patch title, and this patch adds
'imissed' support so it can be added to the patch title, something like:
"net/gve: enable imissed stats for GQ format"

<...>

> +static int gve_alloc_stats_report(struct gve_priv *priv,
> +             uint16_t nb_tx_queues, uint16_t nb_rx_queues)
> +{
> +     char z_name[RTE_MEMZONE_NAMESIZE];
> +     int tx_stats_cnt;
> +     int rx_stats_cnt;
> +
> +     tx_stats_cnt = (GVE_TX_STATS_REPORT_NUM + NIC_TX_STATS_REPORT_NUM) *
> +             nb_tx_queues;
> +     rx_stats_cnt = (GVE_RX_STATS_REPORT_NUM + NIC_RX_STATS_REPORT_NUM) *
> +             nb_rx_queues;
> +     priv->stats_report_len = sizeof(struct gve_stats_report) +
> +             sizeof(struct stats) * (tx_stats_cnt + rx_stats_cnt);
> +
> +     snprintf(z_name, sizeof(z_name), "stats_report_%s", priv->pci_dev->device.name);
>

Can you please add 'gve_' prefix to the memzone name, to prevent any
possible collision.

Done. 

<...>

> +static void gve_free_stats_report(struct rte_eth_dev *dev)
> +{
> +     struct gve_priv *priv = dev->data->dev_private;
> +     rte_memzone_free(priv->stats_report_mem);
>

What will happen if user asks stats/xstats after port stopped?

Good catch. I have added a null check so that the driver doesn't try to read stats from memory region that doesn't exist. 

<...>

>  gve_dev_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *stats)
>  {
>       uint16_t i;
> +     if (gve_is_gqi(dev->data->dev_private))
> +             gve_get_imissed_from_nic(dev);
> 

This updates imissed in RxQ struct for all queues for basic stats, but
what if user only calls xstats, I guess in that case stat won't be updated.

 

Yes; that is expected. Since imissed is a member of rte_eth_stats; calling gve_dev_stats_get is the right way to get this stat.