Re: [PATCH net-next v5 3/7] bnxt_en: add support for tcp-data-split ethtool command

[Andy Gospodarek <andrew.gospodarek@broadcom.com>]

On Wed, Nov 13, 2024 at 05:32:17PM +0000, Taehee Yoo wrote:
> NICs that uses bnxt_en driver supports tcp-data-split feature by the
> name of HDS(header-data-split).
> But there is no implementation for the HDS to enable by ethtool.
> Only getting the current HDS status is implemented and The HDS is just
> automatically enabled only when either LRO, HW-GRO, or JUMBO is enabled.
> The hds_threshold follows rx-copybreak value. and it was unchangeable.
> 
> This implements `ethtool -G <interface name> tcp-data-split <value>`
> command option.
> The value can be <on> and <auto>.
> The value is <auto> and one of LRO/GRO/JUMBO is enabled, HDS is
> automatically enabled and all LRO/GRO/JUMBO are disabled, HDS is
> automatically disabled.
> 
> HDS feature relies on the aggregation ring.
> So, if HDS is enabled, the bnxt_en driver initializes the aggregation ring.
> This is the reason why BNXT_FLAG_AGG_RINGS contains HDS condition.
> 
> Tested-by: Stanislav Fomichev <sdf@fomichev.me>
> Signed-off-by: Taehee Yoo <ap420073@gmail.com>

Tested-by: Andy Gospodarek <gospo@broadcom.com>

> ---
> 
> v5:
>  - Do not set HDS if XDP is attached.
>  - Enable tcp-data-split only when tcp_data_split_mod is true.
> 
> v4:
>  - Do not support disable tcp-data-split.
>  - Add Test tag from Stanislav.
> 
> v3:
>  - No changes.
> 
> v2:
>  - Do not set hds_threshold to 0.
> 
>  drivers/net/ethernet/broadcom/bnxt/bnxt.c     |  2 +-
>  drivers/net/ethernet/broadcom/bnxt/bnxt.h     |  5 +++--
>  .../net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 19 +++++++++++++++++++
>  3 files changed, 23 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> index d521b8918c02..608bcca71676 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> @@ -4474,7 +4474,7 @@ void bnxt_set_ring_params(struct bnxt *bp)
>  	bp->rx_agg_ring_size = 0;
>  	bp->rx_agg_nr_pages = 0;
>  
> -	if (bp->flags & BNXT_FLAG_TPA)
> +	if (bp->flags & BNXT_FLAG_TPA || bp->flags & BNXT_FLAG_HDS)
>  		agg_factor = min_t(u32, 4, 65536 / BNXT_RX_PAGE_SIZE);
>  
>  	bp->flags &= ~BNXT_FLAG_JUMBO;
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
> index d1eef880eec5..3a7d2f3ebb2a 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
> @@ -2202,8 +2202,6 @@ struct bnxt {
>  	#define BNXT_FLAG_TPA		(BNXT_FLAG_LRO | BNXT_FLAG_GRO)
>  	#define BNXT_FLAG_JUMBO		0x10
>  	#define BNXT_FLAG_STRIP_VLAN	0x20
> -	#define BNXT_FLAG_AGG_RINGS	(BNXT_FLAG_JUMBO | BNXT_FLAG_GRO | \
> -					 BNXT_FLAG_LRO)
>  	#define BNXT_FLAG_RFS		0x100
>  	#define BNXT_FLAG_SHARED_RINGS	0x200
>  	#define BNXT_FLAG_PORT_STATS	0x400
> @@ -2224,6 +2222,9 @@ struct bnxt {
>  	#define BNXT_FLAG_ROCE_MIRROR_CAP	0x4000000
>  	#define BNXT_FLAG_TX_COAL_CMPL	0x8000000
>  	#define BNXT_FLAG_PORT_STATS_EXT	0x10000000
> +	#define BNXT_FLAG_HDS		0x20000000
> +	#define BNXT_FLAG_AGG_RINGS	(BNXT_FLAG_JUMBO | BNXT_FLAG_GRO | \
> +					 BNXT_FLAG_LRO | BNXT_FLAG_HDS)
>  
>  	#define BNXT_FLAG_ALL_CONFIG_FEATS (BNXT_FLAG_TPA |		\
>  					    BNXT_FLAG_RFS |		\
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
> index adf30d1f738f..b0054eef389b 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
> @@ -840,6 +840,8 @@ static int bnxt_set_ringparam(struct net_device *dev,
>  			      struct kernel_ethtool_ringparam *kernel_ering,
>  			      struct netlink_ext_ack *extack)
>  {
> +	u8 tcp_data_split_mod = kernel_ering->tcp_data_split_mod;
> +	u8 tcp_data_split = kernel_ering->tcp_data_split;
>  	struct bnxt *bp = netdev_priv(dev);
>  
>  	if ((ering->rx_pending > BNXT_MAX_RX_DESC_CNT) ||
> @@ -847,9 +849,25 @@ static int bnxt_set_ringparam(struct net_device *dev,
>  	    (ering->tx_pending < BNXT_MIN_TX_DESC_CNT))
>  		return -EINVAL;
>  
> +	if (tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_DISABLED &&
> +	    tcp_data_split_mod)
> +		return -EOPNOTSUPP;
> +
> +	if (tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_ENABLED &&
> +	    tcp_data_split_mod && BNXT_RX_PAGE_MODE(bp)) {
> +		NL_SET_ERR_MSG_MOD(extack, "tcp-data-split is disallowed when XDP is attached");
> +		return -EOPNOTSUPP;
> +	}
> +
>  	if (netif_running(dev))
>  		bnxt_close_nic(bp, false, false);
>  
> +	if (tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_ENABLED &&
> +	    tcp_data_split_mod)
> +		bp->flags |= BNXT_FLAG_HDS;
> +	else if (tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_UNKNOWN)
> +		bp->flags &= ~BNXT_FLAG_HDS;
> +
>  	bp->rx_ring_size = ering->rx_pending;
>  	bp->tx_ring_size = ering->tx_pending;
>  	bnxt_set_ring_params(bp);
> @@ -5345,6 +5363,7 @@ const struct ethtool_ops bnxt_ethtool_ops = {
>  				     ETHTOOL_COALESCE_STATS_BLOCK_USECS |
>  				     ETHTOOL_COALESCE_USE_ADAPTIVE_RX |
>  				     ETHTOOL_COALESCE_USE_CQE,
> +	.supported_ring_params	= ETHTOOL_RING_USE_TCP_DATA_SPLIT,
>  	.get_link_ksettings	= bnxt_get_link_ksettings,
>  	.set_link_ksettings	= bnxt_set_link_ksettings,
>  	.get_fec_stats		= bnxt_get_fec_stats,
> -- 
> 2.34.1
>