Re: [PATCH v9 net-next 08/11] net: dsa: microchip: add support for ethtool port counters

[Andrew Lunn]

On Fri, Mar 18, 2022 at 02:25:37PM +0530, Prasanna Vengateshan wrote:
> Added support for get_eth_**_stats() (phy/mac/ctrl) and
> get_stats64()
> 
> Reused the KSZ common APIs for get_ethtool_stats() & get_sset_count()
> along with relevant lan937x hooks for KSZ common layer and added
> support for get_strings()


> +static void lan937x_get_stats64(struct dsa_switch *ds, int port,
> +				struct rtnl_link_stats64 *s)
> +{
> +	struct ksz_device *dev = ds->priv;
> +	struct ksz_port_mib *mib = &dev->ports[port].mib;
> +	u64 *ctr = mib->counters;
> +
> +	mutex_lock(&mib->cnt_mutex);

I think for stats64 you are not allowed to block.

https://lore.kernel.org/netdev/20220218104330.g3vfbpdqltdkp4sr@skbuf/T/

There was talk of changing this. but i don't think it ever happened.

      Andrew