[Intel-wired-lan] [PATCH iwl-next v1 2/3] igc: expose RSS key via ethtool get_rxfh

[Loktionov, Aleksandr]

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces at osuosl.org> On Behalf
> Of Kohei Enju
> Sent: Saturday, October 25, 2025 5:02 PM
> To: intel-wired-lan at lists.osuosl.org; netdev at vger.kernel.org
> Cc: Nguyen, Anthony L <anthony.l.nguyen at intel.com>; Kitszel,
> Przemyslaw <przemyslaw.kitszel at intel.com>; Andrew Lunn
> <andrew+netdev at lunn.ch>; David S. Miller <davem at davemloft.net>; Eric
> Dumazet <edumazet at google.com>; Jakub Kicinski <kuba at kernel.org>; Paolo
> Abeni <pabeni at redhat.com>; kohei.enju at gmail.com; Kohei Enju
> <enjuk at amazon.com>
> Subject: [Intel-wired-lan] [PATCH iwl-next v1 2/3] igc: expose RSS key
> via ethtool get_rxfh
> 
> Implement igc_ethtool_get_rxfh_key_size() and extend
> igc_ethtool_get_rxfh() to return the RSS key to userspace.
> 
> This can be tested using `ethtool -x <dev>`.
> 
> Signed-off-by: Kohei Enju <enjuk at amazon.com>
> ---
>  drivers/net/ethernet/intel/igc/igc_ethtool.c | 17 +++++++++++++----
>  1 file changed, 13 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/igc/igc_ethtool.c
> b/drivers/net/ethernet/intel/igc/igc_ethtool.c
> index f89c2cbaace0..0482e590bc5a 100644
> --- a/drivers/net/ethernet/intel/igc/igc_ethtool.c
> +++ b/drivers/net/ethernet/intel/igc/igc_ethtool.c
> @@ -1490,6 +1490,11 @@ void igc_write_rss_indir_tbl(struct igc_adapter
> *adapter)
>  	}
>  }
> 
> +static u32 igc_ethtool_get_rxfh_key_size(struct net_device *netdev) {
> +	return IGC_RSS_KEY_SIZE;
> +}
> +
>  static u32 igc_ethtool_get_rxfh_indir_size(struct net_device *netdev)
> {
>  	return IGC_RETA_SIZE;
> @@ -1502,10 +1507,13 @@ static int igc_ethtool_get_rxfh(struct
> net_device *netdev,
>  	int i;
> 
>  	rxfh->hfunc = ETH_RSS_HASH_TOP;
> -	if (!rxfh->indir)
> -		return 0;
> -	for (i = 0; i < IGC_RETA_SIZE; i++)
> -		rxfh->indir[i] = adapter->rss_indir_tbl[i];
> +
> +	if (rxfh->indir)
> +		for (i = 0; i < IGC_RETA_SIZE; i++)
> +			rxfh->indir[i] = adapter->rss_indir_tbl[i];
> +
> +	if (rxfh->key)
> +		memcpy(rxfh->key, adapter->rss_key, sizeof(adapter-
> >rss_key));
> 
>  	return 0;
>  }
> @@ -2182,6 +2190,7 @@ static const struct ethtool_ops igc_ethtool_ops
> = {
>  	.set_coalesce		= igc_ethtool_set_coalesce,
>  	.get_rxnfc		= igc_ethtool_get_rxnfc,
>  	.set_rxnfc		= igc_ethtool_set_rxnfc,
> +	.get_rxfh_key_size	= igc_ethtool_get_rxfh_key_size,
>  	.get_rxfh_indir_size	= igc_ethtool_get_rxfh_indir_size,
>  	.get_rxfh		= igc_ethtool_get_rxfh,
>  	.set_rxfh		= igc_ethtool_set_rxfh,
> --
> 2.51.0

Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov at intel.com>