Re: [RFC Patch net-next v1 9/9] r8169: add support for ethtool

Subbaraya Sundeep
2026-04-26T18:34:49Z

Hi,
On 2026-04-20 at 07:49:57, javen (javen_xu@realsil.com.cn) wrote:
> From: Javen Xu <javen_xu@realsil.com.cn>
>
> This patch add support for changing rx queues by ethtool. We can set rx
> 1, 2, 4, 8 by ethtool -L eth1 rx num.
>
> Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
> ---
> drivers/net/ethernet/realtek/r8169_main.c | 68 +++++++++++++++++++++++
> 1 file changed, 68 insertions(+)
>
> diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
> index 6b574fc336d6..57087abe7d88 100644
> --- a/drivers/net/ethernet/realtek/r8169_main.c
> +++ b/drivers/net/ethernet/realtek/r8169_main.c
> @@ -6518,6 +6518,72 @@ static void r8169_init_napi(struct rtl8169_private *tp)
> }
> }
>
> +static void rtl8169_get_channels(struct net_device *dev,
> + struct ethtool_channels *ch)
> +{
> + struct rtl8169_private *tp = netdev_priv(dev);
> +
> + ch->max_rx = tp->HwSuppNumRxQueues ? tp->HwSuppNumRxQueues : 1;
> + ch->max_tx = tp->HwSuppNumTxQueues ? tp->HwSuppNumTxQueues : 1;
> + ch->max_other = 0;
> + ch->max_combined = 0;
> +
> + ch->rx_count = tp->num_rx_rings;
> + ch->tx_count = tp->num_tx_rings;
> + ch->other_count = 0;
> + ch->combined_count = 0;
> +}
> +
> +static int rtl8169_set_channels(struct net_device *dev,
> + struct ethtool_channels *ch)
> +{
> + struct rtl8169_private *tp = netdev_priv(dev);
> + bool if_running = netif_running(dev);
> + int i;
> +
> + if (!tp->rss_support && (ch->rx_count > 1 || ch->tx_count > 1)) {
> + netdev_warn(dev, "This chip does not support multiple channels/RSS.\n");
> + return -EOPNOTSUPP;
> + }
> +
> + if (ch->rx_count == 0 || ch->tx_count == 0)
> + return -EINVAL;
> + if (ch->rx_count > tp->HwSuppNumRxQueues ||
> + ch->tx_count > tp->HwSuppNumTxQueues)
> + return -EINVAL;
> + if (ch->other_count || ch->combined_count)
> + return -EINVAL;
> +
> + if (ch->rx_count == tp->num_rx_rings &&
> + ch->tx_count == tp->num_tx_rings)
> + return 0;
> +
Revisit the above checks, they are not needed since ethtool code does all these.
> + if (if_running)
> + rtl8169_close(dev);
> +
> + tp->num_rx_rings = ch->rx_count;
> + tp->num_tx_rings = ch->tx_count;
> +
> + tp->rss_enable = (tp->num_rx_rings > 1 && tp->rss_support);
Please help me understand your HW..Is there a condition where there are
multi Rx queues but HW do not support RSS? I dont know how traffic is distributed
across queues in that case (maybe - pinning flows to individual queues via
ntuple or TC ?)

Thanks,
Sundeep

> +
> + for (i = 0; i < tp->HwSuppIndirTblEntries; i++) {
> + if (tp->rss_enable)
> + tp->rss_indir_tbl[i] = ethtool_rxfh_indir_default(i, tp->num_rx_rings);
> + else
> + tp->rss_indir_tbl[i] = 0;
> + }
> +
> + if (tp->rss_enable)
> + tp->InitRxDescType = RX_DESC_RING_TYPE_RSS;
> + else
> + tp->InitRxDescType = RX_DESC_RING_TYPE_DEAFULT;
> +
> + if (if_running)
> + return rtl_open(dev);
> +
> + return 0;
> +}
> +
> static const struct ethtool_ops rtl8169_ethtool_ops = {
> .supported_coalesce_params = ETHTOOL_COALESCE_USECS |
> ETHTOOL_COALESCE_MAX_FRAMES,
> @@ -6536,6 +6602,8 @@ static const struct ethtool_ops rtl8169_ethtool_ops = {
> .nway_reset = phy_ethtool_nway_reset,
> .get_eee = rtl8169_get_eee,
> .set_eee = rtl8169_set_eee,
> + .get_channels = rtl8169_get_channels,
> + .set_channels = rtl8169_set_channels,
> .get_link_ksettings = phy_ethtool_get_link_ksettings,
> .set_link_ksettings = rtl8169_set_link_ksettings,
> .get_ringparam = rtl8169_get_ringparam,
> --
> 2.43.0
>