Re: [PATCH net-next 10/15] ethtool: provide ring sizes with RINGS_GET request

[Jakub Kicinski]

On Wed, 11 Mar 2020 22:40:53 +0100 (CET) Michal Kubecek wrote:
> +static int rings_prepare_data(const struct ethnl_req_info *req_base,
> +			      struct ethnl_reply_data *reply_base,
> +			      struct genl_info *info)
> +{
> +	struct rings_reply_data *data = RINGS_REPDATA(reply_base);
> +	struct net_device *dev = reply_base->dev;
> +	int ret;
> +
> +	if (!dev->ethtool_ops->get_ringparam)
> +		return -EOPNOTSUPP;
> +	ret = ethnl_ops_begin(dev);
> +	if (ret < 0)
> +		return ret;
> +	dev->ethtool_ops->get_ringparam(dev, &data->ringparam);
> +	ret = 0;
> +	ethnl_ops_complete(dev);
> +
> +	return ret;

nit: just return 0 and drop ret = 0 above, there is no goto here

> +}
> +
> +static int rings_reply_size(const struct ethnl_req_info *req_base,
> +			    const struct ethnl_reply_data *reply_base)
> +{
> +	return 8 * nla_total_size(sizeof(u32))

nit: 8 is a little bit of a magic constant

> +		+ 0;

nit: personally not a huge fan

> +}
> +
> +static int rings_fill_reply(struct sk_buff *skb,
> +			    const struct ethnl_req_info *req_base,
> +			    const struct ethnl_reply_data *reply_base)
> +{
> +	const struct rings_reply_data *data = RINGS_REPDATA(reply_base);
> +	const struct ethtool_ringparam *ringparam = &data->ringparam;
> +
> +	if (nla_put_u32(skb, ETHTOOL_A_RINGS_RX_MAX,
> +			ringparam->rx_max_pending) ||
> +	    nla_put_u32(skb, ETHTOOL_A_RINGS_RX_MINI_MAX,
> +			ringparam->rx_mini_max_pending) ||
> +	    nla_put_u32(skb, ETHTOOL_A_RINGS_RX_JUMBO_MAX,
> +			ringparam->rx_jumbo_max_pending) ||
> +	    nla_put_u32(skb, ETHTOOL_A_RINGS_TX_MAX,
> +			ringparam->tx_max_pending) ||
> +	    nla_put_u32(skb, ETHTOOL_A_RINGS_RX,
> +			ringparam->rx_pending) ||
> +	    nla_put_u32(skb, ETHTOOL_A_RINGS_RX_MINI,
> +			ringparam->rx_mini_pending) ||
> +	    nla_put_u32(skb, ETHTOOL_A_RINGS_RX_JUMBO,
> +			ringparam->rx_jumbo_pending) ||
> +	    nla_put_u32(skb, ETHTOOL_A_RINGS_TX,
> +			ringparam->tx_pending))
> +		return -EMSGSIZE;

nit: I wonder if it's necessary to report the zero values..

Reviewed-by: Jakub Kicinski <kuba@xxxxxxxxxx>