Re: [PATCH 3/4] drivers/net/virtio_net: Added RSS hash report.

[Jason Wang <jasowang@redhat.com>]

在 2022/1/10 上午5:06, Andrew Melnychenko 写道:
> Added features for RSS hash report.
> If hash is provided - it sets to skb.
> Added checks if rss and/or hash are enabled together.
>
> Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
> ---
>   drivers/net/virtio_net.c | 56 ++++++++++++++++++++++++++++++++++------
>   1 file changed, 48 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 21794731fc75..6e7461b01f87 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -231,6 +231,7 @@ struct virtnet_info {
>   
>   	/* Host supports rss and/or hash report */
>   	bool has_rss;
> +	bool has_rss_hash_report;
>   	u8 rss_key_size;
>   	u16 rss_indir_table_size;
>   	u32 rss_hash_types_supported;
> @@ -424,7 +425,9 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi,
>   	hdr_p = p;
>   
>   	hdr_len = vi->hdr_len;
> -	if (vi->mergeable_rx_bufs)
> +	if (vi->has_rss_hash_report)
> +		hdr_padded_len = sizeof(struct virtio_net_hdr_v1_hash);
> +	else if (vi->mergeable_rx_bufs)
>   		hdr_padded_len = sizeof(*hdr);
>   	else
>   		hdr_padded_len = sizeof(struct padded_vnet_hdr);
> @@ -1160,6 +1163,8 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
>   	struct net_device *dev = vi->dev;
>   	struct sk_buff *skb;
>   	struct virtio_net_hdr_mrg_rxbuf *hdr;
> +	struct virtio_net_hdr_v1_hash *hdr_hash;
> +	enum pkt_hash_types rss_hash_type;
>   
>   	if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
>   		pr_debug("%s: short packet %i\n", dev->name, len);
> @@ -1186,6 +1191,29 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
>   		return;
>   
>   	hdr = skb_vnet_hdr(skb);
> +	if (dev->features & NETIF_F_RXHASH) {
> +		hdr_hash = (struct virtio_net_hdr_v1_hash *)(hdr);
> +
> +		switch (hdr_hash->hash_report) {
> +		case VIRTIO_NET_HASH_REPORT_TCPv4:
> +		case VIRTIO_NET_HASH_REPORT_UDPv4:
> +		case VIRTIO_NET_HASH_REPORT_TCPv6:
> +		case VIRTIO_NET_HASH_REPORT_UDPv6:
> +		case VIRTIO_NET_HASH_REPORT_TCPv6_EX:
> +		case VIRTIO_NET_HASH_REPORT_UDPv6_EX:
> +			rss_hash_type = PKT_HASH_TYPE_L4;
> +			break;
> +		case VIRTIO_NET_HASH_REPORT_IPv4:
> +		case VIRTIO_NET_HASH_REPORT_IPv6:
> +		case VIRTIO_NET_HASH_REPORT_IPv6_EX:
> +			rss_hash_type = PKT_HASH_TYPE_L3;
> +			break;
> +		case VIRTIO_NET_HASH_REPORT_NONE:
> +		default:
> +			rss_hash_type = PKT_HASH_TYPE_NONE;
> +		}
> +		skb_set_hash(skb, hdr_hash->hash_value, rss_hash_type);
> +	}
>   
>   	if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
>   		skb->ip_summed = CHECKSUM_UNNECESSARY;
> @@ -2233,7 +2261,8 @@ static bool virtnet_commit_rss_command(struct virtnet_info *vi)
>   	sg_set_buf(&sgs[3], vi->ctrl->rss.key, sg_buf_size);
>   
>   	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
> -				  VIRTIO_NET_CTRL_MQ_RSS_CONFIG, sgs)) {
> +				  vi->has_rss ? VIRTIO_NET_CTRL_MQ_RSS_CONFIG
> +				  : VIRTIO_NET_CTRL_MQ_HASH_CONFIG, sgs)) {
>   		dev_warn(&dev->dev, "VIRTIONET issue with committing RSS sgs\n");
>   		return false;
>   	}
> @@ -3220,7 +3249,9 @@ static bool virtnet_validate_features(struct virtio_device *vdev)
>   	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
>   	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
>   			     "VIRTIO_NET_F_CTRL_VQ") ||
> -	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS, "VIRTIO_NET_F_RSS"))) {
> +	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS, "VIRTIO_NET_F_RSS") ||


I think we should make RSS depend on CTRL_VQ.


> +	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT,
> +			     "VIRTIO_NET_F_HASH_REPORT"))) {


Need to depend on CTRL_VQ here.


>   		return false;
>   	}
>   
> @@ -3355,6 +3386,12 @@ static int virtnet_probe(struct virtio_device *vdev)
>   	if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
>   		vi->mergeable_rx_bufs = true;
>   
> +	if (virtio_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT)) {
> +		vi->has_rss_hash_report = true;
> +		vi->rss_indir_table_size = 1;
> +		vi->rss_key_size = VIRTIO_NET_RSS_MAX_KEY_SIZE;


Any reason to initialize RSS feature here not the init_default_rss()?

Thanks


> +	}
> +
>   	if (virtio_has_feature(vdev, VIRTIO_NET_F_RSS)) {
>   		vi->has_rss = true;
>   		vi->rss_indir_table_size =
> @@ -3364,7 +3401,7 @@ static int virtnet_probe(struct virtio_device *vdev)
>   			virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size));
>   	}
>   
> -	if (vi->has_rss) {
> +	if (vi->has_rss || vi->has_rss_hash_report) {
>   		vi->rss_hash_types_supported =
>   		    virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types));
>   		vi->rss_hash_types_supported &=
> @@ -3374,8 +3411,11 @@ static int virtnet_probe(struct virtio_device *vdev)
>   
>   		dev->hw_features |= NETIF_F_RXHASH;
>   	}
> -	if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
> -	    virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
> +
> +	if (vi->has_rss_hash_report)
> +		vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash);
> +	else if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
> +		 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
>   		vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
>   	else
>   		vi->hdr_len = sizeof(struct virtio_net_hdr);
> @@ -3442,7 +3482,7 @@ static int virtnet_probe(struct virtio_device *vdev)
>   		}
>   	}
>   
> -	if (vi->has_rss) {
> +	if (vi->has_rss || vi->has_rss_hash_report) {
>   		rtnl_lock();
>   		virtnet_init_default_rss(vi);
>   		rtnl_unlock();
> @@ -3580,7 +3620,7 @@ static struct virtio_device_id id_table[] = {
>   	VIRTIO_NET_F_CTRL_MAC_ADDR, \
>   	VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \
>   	VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \
> -	VIRTIO_NET_F_RSS
> +	VIRTIO_NET_F_RSS, VIRTIO_NET_F_HASH_REPORT
>   
>   static unsigned int features[] = {
>   	VIRTNET_FEATURES,