Subject: Re: [PATCH net-next v5 2/8] net: ethtool: plumb PHY stats to PHY drivers

From: Jakub Kicinski <[email-masked]>
Date: Tue, 7 Jan 2025 18:02:16 -0800

On Mon,  6 Jan 2025 09:32:55 +0100 Oleksij Rempel wrote:
> +	/**
> +	 * @get_link_stats: Retrieve link statistics.
> +	 * @dev: The PHY device for which the statistics are retrieved.
> +	 * @link_stats: structure where link-specific stats will be stored.
> +	 *
> +	 * Retrieves link-related statistics for the given PHY device. The input
> +	 * structure is pre-initialized with `ETHTOOL_STAT_NOT_SET`, and the
> +	 * driver must only modify members corresponding to supported
> +	 * statistics. Unmodified members will remain set to
> +	 * `ETHTOOL_STAT_NOT_SET` and will not be returned to userspace.
> +	 *
> +	 * Return: 0 on success or a negative error code on failure.

These get callbacks return void

> +	 */
> +	void (*get_link_stats)(struct phy_device *dev,
> +			       struct ethtool_link_ext_stats *link_stats);
>  	/** @get_sset_count: Number of statistic counters */
>  	int (*get_sset_count)(struct phy_device *dev);
>  	/** @get_strings: Names of the statistic counters */
> @@ -1777,6 +1810,49 @@ static inline bool phy_is_pseudo_fixed_link(struct phy_device *phydev)
>  	return phydev->is_pseudo_fixed_link;
>  }
>  
> +/**
> + * phy_ethtool_get_phy_stats - Retrieve standardized PHY statistics
> + * @phydev: Pointer to the PHY device
> + * @phy_stats: Pointer to ethtool_eth_phy_stats structure
> + * @phydev_stats: Pointer to ethtool_phy_stats structure
> + *
> + * Fetches PHY statistics using a kernel-defined interface for consistent
> + * diagnostics. Unlike phy_ethtool_get_stats(), which allows custom stats,
> + * this function enforces a standardized format for better interoperability.
> + */
> +static inline void phy_ethtool_get_phy_stats(struct phy_device *phydev,
> +					struct ethtool_eth_phy_stats *phy_stats,
> +					struct ethtool_phy_stats *phydev_stats)
> +{
> +	if (!phydev->drv || !phydev->drv->get_phy_stats)
> +		return;
> +
> +	mutex_lock(&phydev->lock);
> +	phydev->drv->get_phy_stats(phydev, phy_stats, phydev_stats);
> +	mutex_unlock(&phydev->lock);
> +}
> +
> +/**
> + * phy_ethtool_get_link_ext_stats - Retrieve extended link statistics for a PHY
> + * @phydev: Pointer to the PHY device
> + * @link_stats: Pointer to the structure to store extended link statistics
> + *
> + * Populates the ethtool_link_ext_stats structure with link down event counts
> + * and additional driver-specific link statistics, if available.
> + */
> +static inline void phy_ethtool_get_link_ext_stats(struct phy_device *phydev,
> +				    struct ethtool_link_ext_stats *link_stats)
> +{
> +	link_stats->link_down_events = READ_ONCE(phydev->link_down_events);
> +
> +	if (!phydev->drv || !phydev->drv->get_link_stats)
> +		return;
> +
> +	mutex_lock(&phydev->lock);
> +	phydev->drv->get_link_stats(phydev, link_stats);
> +	mutex_unlock(&phydev->lock);
> +}

Do these have to be static inlines?

Seemds like it will just bloat the header, and make alignment more
painful.