Re: [PATCH 4/4] drivers/net/virtio_net: Added RSS hash report control.

[Jason Wang <jasowang@redhat.com>]

在 2022/1/10 上午5:06, Andrew Melnychenko 写道:
> Now it's possible to control supported hashflows.
> Also added hashflow set/get callbacks.
> Also, disabling RXH_IP_SRC/DST for TCP would disable then for UDP.
> TCP and UDP supports only:
> ethtool -U eth0 rx-flow-hash tcp4 sd
>      RXH_IP_SRC + RXH_IP_DST
> ethtool -U eth0 rx-flow-hash tcp4 sdfn
>      RXH_IP_SRC + RXH_IP_DST + RXH_L4_B_0_1 + RXH_L4_B_2_3
>
> Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
> ---
>   drivers/net/virtio_net.c | 159 +++++++++++++++++++++++++++++++++++++++
>   1 file changed, 159 insertions(+)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 6e7461b01f87..1b8dd384483c 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -235,6 +235,7 @@ struct virtnet_info {
>   	u8 rss_key_size;
>   	u16 rss_indir_table_size;
>   	u32 rss_hash_types_supported;
> +	u32 rss_hash_types_saved;
>   
>   	/* Has control virtqueue */
>   	bool has_cvq;
> @@ -2275,6 +2276,7 @@ static void virtnet_init_default_rss(struct virtnet_info *vi)
>   	int i = 0;
>   
>   	vi->ctrl->rss.table_info.hash_types = vi->rss_hash_types_supported;
> +	vi->rss_hash_types_saved = vi->rss_hash_types_supported;
>   	vi->ctrl->rss.table_info.indirection_table_mask = vi->rss_indir_table_size - 1;
>   	vi->ctrl->rss.table_info.unclassified_queue = 0;
>   
> @@ -2289,6 +2291,131 @@ static void virtnet_init_default_rss(struct virtnet_info *vi)
>   	netdev_rss_key_fill(vi->ctrl->rss.key, vi->rss_key_size);
>   }
>   
> +static void virtnet_get_hashflow(const struct virtnet_info *vi, struct ethtool_rxnfc *info)
> +{
> +	info->data = 0;
> +	switch (info->flow_type) {
> +	case TCP_V4_FLOW:
> +		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv4) {
> +			info->data = RXH_IP_SRC | RXH_IP_DST |
> +						 RXH_L4_B_0_1 | RXH_L4_B_2_3;
> +		} else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
> +			info->data = RXH_IP_SRC | RXH_IP_DST;
> +		}
> +		break;
> +	case TCP_V6_FLOW:
> +		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv6) {
> +			info->data = RXH_IP_SRC | RXH_IP_DST |
> +						 RXH_L4_B_0_1 | RXH_L4_B_2_3;
> +		} else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
> +			info->data = RXH_IP_SRC | RXH_IP_DST;
> +		}
> +		break;
> +	case UDP_V4_FLOW:
> +		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv4) {
> +			info->data = RXH_IP_SRC | RXH_IP_DST |
> +						 RXH_L4_B_0_1 | RXH_L4_B_2_3;
> +		} else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
> +			info->data = RXH_IP_SRC | RXH_IP_DST;
> +		}
> +		break;
> +	case UDP_V6_FLOW:
> +		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv6) {
> +			info->data = RXH_IP_SRC | RXH_IP_DST |
> +						 RXH_L4_B_0_1 | RXH_L4_B_2_3;
> +		} else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
> +			info->data = RXH_IP_SRC | RXH_IP_DST;
> +		}
> +		break;
> +	case IPV4_FLOW:
> +		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4)
> +			info->data = RXH_IP_SRC | RXH_IP_DST;
> +
> +		break;
> +	case IPV6_FLOW:
> +		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4)
> +			info->data = RXH_IP_SRC | RXH_IP_DST;
> +
> +		break;
> +	default:
> +		info->data = 0;
> +		break;
> +	}
> +}
> +
> +static bool virtnet_set_hashflow(struct virtnet_info *vi, struct ethtool_rxnfc *info)
> +{
> +	u64 is_iphash = info->data & (RXH_IP_SRC | RXH_IP_DST);
> +	u64 is_porthash = info->data & (RXH_L4_B_0_1 | RXH_L4_B_2_3);
> +	u32 new_hashtypes = vi->rss_hash_types_saved;
> +
> +	if ((is_iphash && (is_iphash != (RXH_IP_SRC | RXH_IP_DST))) ||
> +	    (is_porthash && (is_porthash != (RXH_L4_B_0_1 | RXH_L4_B_2_3)))) {
> +		return false;
> +	}
> +
> +	if (!is_iphash && is_porthash)
> +		return false;


This seems not filter out all the combinations:

e.g RXH_VLAN with port hash?


> +
> +	switch (info->flow_type) {
> +	case TCP_V4_FLOW:
> +	case UDP_V4_FLOW:
> +	case IPV4_FLOW:
> +		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv4;
> +		if (is_iphash)
> +			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4;
> +
> +		break;
> +	case TCP_V6_FLOW:
> +	case UDP_V6_FLOW:
> +	case IPV6_FLOW:
> +		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv6;
> +		if (is_iphash)
> +			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6;
> +
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	switch (info->flow_type) {
> +	case TCP_V4_FLOW:
> +		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_TCPv4;


Any way to merge the two switch? The code is hard to be reviewed anyhow.


> +		if (is_porthash)
> +			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_TCPv4;
> +
> +		break;
> +	case UDP_V4_FLOW:
> +		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_UDPv4;
> +		if (is_porthash)
> +			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_UDPv4;
> +
> +		break;
> +	case TCP_V6_FLOW:
> +		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_TCPv6;
> +		if (is_porthash)
> +			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_TCPv6;
> +
> +		break;
> +	case UDP_V6_FLOW:
> +		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_UDPv6;
> +		if (is_porthash)
> +			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_UDPv6;
> +
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	if (new_hashtypes != vi->rss_hash_types_saved) {
> +		vi->rss_hash_types_saved = new_hashtypes;
> +		vi->ctrl->rss.table_info.hash_types = vi->rss_hash_types_saved;
> +		if (vi->dev->features & NETIF_F_RXHASH)
> +			return virtnet_commit_rss_command(vi);
> +	}
> +
> +	return true;
> +}
>   
>   static void virtnet_get_drvinfo(struct net_device *dev,
>   				struct ethtool_drvinfo *info)
> @@ -2574,6 +2701,27 @@ static int virtnet_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
>   	switch (info->cmd) {
>   	case ETHTOOL_GRXRINGS:
>   		info->data = vi->curr_queue_pairs;
> +		break;
> +	case ETHTOOL_GRXFH:
> +		virtnet_get_hashflow(vi, info);
> +		break;
> +	default:
> +		rc = -EOPNOTSUPP;
> +	}
> +
> +	return rc;
> +}
> +
> +static int virtnet_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info)
> +{
> +	struct virtnet_info *vi = netdev_priv(dev);
> +	int rc = 0;
> +
> +	switch (info->cmd) {
> +	case ETHTOOL_SRXFH:
> +		if (!virtnet_set_hashflow(vi, info))
> +			rc = -EINVAL;
> +
>   		break;
>   	default:
>   		rc = -EOPNOTSUPP;
> @@ -2602,6 +2750,7 @@ static const struct ethtool_ops virtnet_ethtool_ops = {
>   	.get_rxfh = virtnet_get_rxfh,
>   	.set_rxfh = virtnet_set_rxfh,
>   	.get_rxnfc = virtnet_get_rxnfc,
> +	.set_rxnfc = virtnet_set_rxnfc,
>   };
>   
>   static void virtnet_freeze_down(struct virtio_device *vdev)
> @@ -2854,6 +3003,16 @@ static int virtnet_set_features(struct net_device *dev,
>   		vi->guest_offloads = offloads;
>   	}
>   
> +	if ((dev->features ^ features) & NETIF_F_RXHASH) {
> +		if (features & NETIF_F_RXHASH)
> +			vi->ctrl->rss.table_info.hash_types = vi->rss_hash_types_saved;
> +		else
> +			vi->ctrl->rss.table_info.hash_types = 0;


I think it's better to use VIRTIO_NET_HASH_REPORT_NONE here.

Thanks


> +
> +		if (!virtnet_commit_rss_command(vi))
> +			return -EINVAL;
> +	}
> +
>   	return 0;
>   }
>