Re: [PATCH net-next v3 1/2] gve: Add RSS device option

[Hariprasad Kelam <hkelam@marvell.com>]

On 2024-08-13 at 03:50:12, Praveen Kaligineedi (pkaligineedi@google.com) wrote:
> From: Ziwei Xiao <ziweixiao@google.com>
> 
> Add a device option to inform the driver about the hash key size and
> hash table size used by the device. This information will be stored and
> made available for RSS ethtool operations.
> 
> Signed-off-by: Ziwei Xiao <ziweixiao@google.com>
> Signed-off-by: Praveen Kaligineedi <pkaligineedi@google.com>
> Reviewed-by: Praveen Kaligineedi <pkaligineedi@google.com>
> Reviewed-by: Harshitha Ramamurthy <hramamurthy@google.com>
> Reviewed-by: Willem de Bruijn <willemb@google.com>
> ---
> Changes in v2:
> 	- Unify the RSS argument order in related functions(Jakub Kicinski)
> 
>  drivers/net/ethernet/google/gve/gve.h        |  3 ++
>  drivers/net/ethernet/google/gve/gve_adminq.c | 36 ++++++++++++++++++--
>  drivers/net/ethernet/google/gve/gve_adminq.h | 15 +++++++-
>  3 files changed, 51 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ethernet/google/gve/gve.h b/drivers/net/ethernet/google/gve/gve.h
> index 84ac004d3953..6c21f3c53619 100644
> --- a/drivers/net/ethernet/google/gve/gve.h
> +++ b/drivers/net/ethernet/google/gve/gve.h
> @@ -831,6 +831,9 @@ struct gve_priv {
>  	u32 num_flow_rules;
>  
>  	struct gve_flow_rules_cache flow_rules_cache;
> +
> +	u16 rss_key_size;
> +	u16 rss_lut_size;
>  };
>  
>  enum gve_service_task_flags_bit {
> diff --git a/drivers/net/ethernet/google/gve/gve_adminq.c b/drivers/net/ethernet/google/gve/gve_adminq.c
> index c5bbc1b7524e..b5c801d2f8b5 100644
> --- a/drivers/net/ethernet/google/gve/gve_adminq.c
> +++ b/drivers/net/ethernet/google/gve/gve_adminq.c
> @@ -45,6 +45,7 @@ void gve_parse_device_option(struct gve_priv *priv,
>  			     struct gve_device_option_dqo_qpl **dev_op_dqo_qpl,
>  			     struct gve_device_option_buffer_sizes **dev_op_buffer_sizes,
>  			     struct gve_device_option_flow_steering **dev_op_flow_steering,
> +			     struct gve_device_option_rss_config **dev_op_rss_config,
>  			     struct gve_device_option_modify_ring **dev_op_modify_ring)
>  {
>  	u32 req_feat_mask = be32_to_cpu(option->required_features_mask);
> @@ -207,6 +208,23 @@ void gve_parse_device_option(struct gve_priv *priv,
>  				 "Flow Steering");
>  		*dev_op_flow_steering = (void *)(option + 1);
>  		break;
> +	case GVE_DEV_OPT_ID_RSS_CONFIG:
> +		if (option_length < sizeof(**dev_op_rss_config) ||
> +		    req_feat_mask != GVE_DEV_OPT_REQ_FEAT_MASK_RSS_CONFIG) {
> +			dev_warn(&priv->pdev->dev, GVE_DEVICE_OPTION_ERROR_FMT,
> +				 "RSS config",
> +				 (int)sizeof(**dev_op_rss_config),
> +				 GVE_DEV_OPT_REQ_FEAT_MASK_RSS_CONFIG,
> +				 option_length, req_feat_mask);
> +			break;
> +		}
> +
> +		if (option_length > sizeof(**dev_op_rss_config))
> +			dev_warn(&priv->pdev->dev,
> +				 GVE_DEVICE_OPTION_TOO_BIG_FMT,
> +				 "RSS config");
> +		*dev_op_rss_config = (void *)(option + 1);
> +		break;
>  	default:
>  		/* If we don't recognize the option just continue
>  		 * without doing anything.
> @@ -227,6 +245,7 @@ gve_process_device_options(struct gve_priv *priv,
>  			   struct gve_device_option_dqo_qpl **dev_op_dqo_qpl,
>  			   struct gve_device_option_buffer_sizes **dev_op_buffer_sizes,
>  			   struct gve_device_option_flow_steering **dev_op_flow_steering,
> +			   struct gve_device_option_rss_config **dev_op_rss_config,
>  			   struct gve_device_option_modify_ring **dev_op_modify_ring)
>  {
>  	const int num_options = be16_to_cpu(descriptor->num_device_options);
> @@ -249,7 +268,8 @@ gve_process_device_options(struct gve_priv *priv,
>  					dev_op_gqi_rda, dev_op_gqi_qpl,
>  					dev_op_dqo_rda, dev_op_jumbo_frames,
>  					dev_op_dqo_qpl, dev_op_buffer_sizes,
> -					dev_op_flow_steering, dev_op_modify_ring);
> +					dev_op_flow_steering, dev_op_rss_config,
> +					dev_op_modify_ring);
>  		dev_opt = next_opt;
>  	}
>  
> @@ -867,6 +887,8 @@ static void gve_enable_supported_features(struct gve_priv *priv,
>  					  *dev_op_buffer_sizes,
>  					  const struct gve_device_option_flow_steering
>  					  *dev_op_flow_steering,
> +					  const struct gve_device_option_rss_config
> +					  *dev_op_rss_config,
>  					  const struct gve_device_option_modify_ring
>  					  *dev_op_modify_ring)
>  {
> @@ -931,6 +953,14 @@ static void gve_enable_supported_features(struct gve_priv *priv,
>  				 priv->max_flow_rules);
>  		}
>  	}
> +
> +	if (dev_op_rss_config &&
> +	    (supported_features_mask & GVE_SUP_RSS_CONFIG_MASK)) {
> +		priv->rss_key_size =
> +			be16_to_cpu(dev_op_rss_config->hash_key_size);
> +		priv->rss_lut_size =
> +			be16_to_cpu(dev_op_rss_config->hash_lut_size);
> +	}
>  }
>  
>  int gve_adminq_describe_device(struct gve_priv *priv)
> @@ -939,6 +969,7 @@ int gve_adminq_describe_device(struct gve_priv *priv)
>  	struct gve_device_option_buffer_sizes *dev_op_buffer_sizes = NULL;
>  	struct gve_device_option_jumbo_frames *dev_op_jumbo_frames = NULL;
>  	struct gve_device_option_modify_ring *dev_op_modify_ring = NULL;
> +	struct gve_device_option_rss_config *dev_op_rss_config = NULL;
>  	struct gve_device_option_gqi_rda *dev_op_gqi_rda = NULL;
>  	struct gve_device_option_gqi_qpl *dev_op_gqi_qpl = NULL;
>  	struct gve_device_option_dqo_rda *dev_op_dqo_rda = NULL;
> @@ -973,6 +1004,7 @@ int gve_adminq_describe_device(struct gve_priv *priv)
>  					 &dev_op_jumbo_frames, &dev_op_dqo_qpl,
>  					 &dev_op_buffer_sizes,
>  					 &dev_op_flow_steering,
> +					 &dev_op_rss_config,
>  					 &dev_op_modify_ring);
>  	if (err)
>  		goto free_device_descriptor;
> @@ -1035,7 +1067,7 @@ int gve_adminq_describe_device(struct gve_priv *priv)
>  	gve_enable_supported_features(priv, supported_features_mask,
>  				      dev_op_jumbo_frames, dev_op_dqo_qpl,
>  				      dev_op_buffer_sizes, dev_op_flow_steering,
> -				      dev_op_modify_ring);
> +				      dev_op_rss_config, dev_op_modify_ring);
>  
>  free_device_descriptor:
>  	dma_pool_free(priv->adminq_pool, descriptor, descriptor_bus);
> diff --git a/drivers/net/ethernet/google/gve/gve_adminq.h b/drivers/net/ethernet/google/gve/gve_adminq.h
> index ed1370c9b197..7d9ef9a12fef 100644
> --- a/drivers/net/ethernet/google/gve/gve_adminq.h
> +++ b/drivers/net/ethernet/google/gve/gve_adminq.h
> @@ -164,6 +164,14 @@ struct gve_device_option_flow_steering {
>  
>  static_assert(sizeof(struct gve_device_option_flow_steering) == 12);
>  
> +struct gve_device_option_rss_config {
> +	__be32 supported_features_mask;
> +	__be16 hash_key_size;
> +	__be16 hash_lut_size;
> +};
> +
> +static_assert(sizeof(struct gve_device_option_rss_config) == 8);
> +
>  /* Terminology:
>   *
>   * RDA - Raw DMA Addressing - Buffers associated with SKBs are directly DMA
> @@ -182,6 +190,7 @@ enum gve_dev_opt_id {
>  	GVE_DEV_OPT_ID_JUMBO_FRAMES		= 0x8,
>  	GVE_DEV_OPT_ID_BUFFER_SIZES		= 0xa,
>  	GVE_DEV_OPT_ID_FLOW_STEERING		= 0xb,
> +	GVE_DEV_OPT_ID_RSS_CONFIG		= 0xe,
>  };
>  
>  enum gve_dev_opt_req_feat_mask {
> @@ -194,6 +203,7 @@ enum gve_dev_opt_req_feat_mask {
>  	GVE_DEV_OPT_REQ_FEAT_MASK_BUFFER_SIZES		= 0x0,
>  	GVE_DEV_OPT_REQ_FEAT_MASK_MODIFY_RING		= 0x0,
>  	GVE_DEV_OPT_REQ_FEAT_MASK_FLOW_STEERING		= 0x0,
> +	GVE_DEV_OPT_REQ_FEAT_MASK_RSS_CONFIG		= 0x0,
>  };
>  
>  enum gve_sup_feature_mask {
> @@ -201,6 +211,7 @@ enum gve_sup_feature_mask {
>  	GVE_SUP_JUMBO_FRAMES_MASK	= 1 << 2,
>  	GVE_SUP_BUFFER_SIZES_MASK	= 1 << 4,
>  	GVE_SUP_FLOW_STEERING_MASK	= 1 << 5,
> +	GVE_SUP_RSS_CONFIG_MASK		= 1 << 7,
Use BIT()

Thanks,
Hariprasad k
>  };