[PATCH v2 0/4] RSS support for VirtioNet.

[PATCH v2 0/4] RSS support for VirtioNet.

[Andrew Melnychenko]

Virtio-net supports "hardware" RSS with toeplitz key.
Also, it allows receiving calculated hash in vheader
that may be used with RPS.
Added ethtools callbacks to manipulate RSS.

Technically hash calculation may be set only for
SRC+DST and SRC+DST+PORTSRC+PORTDST hashflows.
The completely disabling hash calculation for TCP or UDP
would disable hash calculation for IP.

RSS/RXHASH is disabled by default.

Changes since v1:
* refactored virtnet_set_hashflow
* refactored virtio_net_ctrl_rss
* moved hunks between patches a bit

Changes since rfc:
* code refactored
* patches reformatted
* added feature validation

Andrew Melnychenko (4):
  drivers/net/virtio_net: Fixed padded vheader to use v1 with hash.
  drivers/net/virtio_net: Added basic RSS support.
  drivers/net/virtio_net: Added RSS hash report.
  drivers/net/virtio_net: Added RSS hash report control.

 drivers/net/virtio_net.c | 383 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 370 insertions(+), 13 deletions(-)

-- 
2.34.1

[PATCH v2 1/4] drivers/net/virtio_net: Fixed padded vheader to use v1 with hash.

[Andrew Melnychenko]

The header v1 provides additional info about RSS.
Added changes to computing proper header length.
In the next patches, the header may contain RSS hash info
for the hash population.

Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
---
 drivers/net/virtio_net.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 569eecfbc2cd..05fe5ba32187 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -242,13 +242,13 @@ struct virtnet_info {
 };
 
 struct padded_vnet_hdr {
-	struct virtio_net_hdr_mrg_rxbuf hdr;
+	struct virtio_net_hdr_v1_hash hdr;
 	/*
 	 * hdr is in a separate sg buffer, and data sg buffer shares same page
 	 * with this header sg. This padding makes next sg 16 byte aligned
 	 * after the header.
 	 */
-	char padding[4];
+	char padding[12];
 };
 
 static bool is_xdp_frame(void *ptr)
@@ -1266,7 +1266,8 @@ static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
 					  struct ewma_pkt_len *avg_pkt_len,
 					  unsigned int room)
 {
-	const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+	struct virtnet_info *vi = rq->vq->vdev->priv;
+	const size_t hdr_len = vi->hdr_len;
 	unsigned int len;
 
 	if (room)
@@ -2851,7 +2852,7 @@ static void virtnet_del_vqs(struct virtnet_info *vi)
  */
 static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
 {
-	const unsigned int hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+	const unsigned int hdr_len = vi->hdr_len;
 	unsigned int rq_size = virtqueue_get_vring_size(vq);
 	unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
 	unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
-- 
2.34.1

Re: [PATCH v2 1/4] drivers/net/virtio_net: Fixed padded vheader to use v1 with hash.

[Jason Wang]

在 2022/1/17 下午4:00, Andrew Melnychenko 写道:
> The header v1 provides additional info about RSS.
> Added changes to computing proper header length.
> In the next patches, the header may contain RSS hash info
> for the hash population.
>
> Signed-off-by: Andrew Melnychenko <andrew@daynix.com>


Acked-by: Jason Wang <jasowang@redhat.com>


> ---
>   drivers/net/virtio_net.c | 9 +++++----
>   1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 569eecfbc2cd..05fe5ba32187 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -242,13 +242,13 @@ struct virtnet_info {
>   };
>   
>   struct padded_vnet_hdr {
> -	struct virtio_net_hdr_mrg_rxbuf hdr;
> +	struct virtio_net_hdr_v1_hash hdr;
>   	/*
>   	 * hdr is in a separate sg buffer, and data sg buffer shares same page
>   	 * with this header sg. This padding makes next sg 16 byte aligned
>   	 * after the header.
>   	 */
> -	char padding[4];
> +	char padding[12];
>   };
>   
>   static bool is_xdp_frame(void *ptr)
> @@ -1266,7 +1266,8 @@ static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
>   					  struct ewma_pkt_len *avg_pkt_len,
>   					  unsigned int room)
>   {
> -	const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
> +	struct virtnet_info *vi = rq->vq->vdev->priv;
> +	const size_t hdr_len = vi->hdr_len;
>   	unsigned int len;
>   
>   	if (room)
> @@ -2851,7 +2852,7 @@ static void virtnet_del_vqs(struct virtnet_info *vi)
>    */
>   static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
>   {
> -	const unsigned int hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
> +	const unsigned int hdr_len = vi->hdr_len;
>   	unsigned int rq_size = virtqueue_get_vring_size(vq);
>   	unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
>   	unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;

[PATCH v2 2/4] drivers/net/virtio_net: Added basic RSS support.

[Andrew Melnychenko]

Added features for RSS.
Added initialization, RXHASH feature and ethtool ops.
By default RSS/RXHASH is disabled.
Virtio RSS "IPv6 extensions" hashes disabled.
Added ethtools ops to set key and indirection table.

Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
---
 drivers/net/virtio_net.c | 193 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 187 insertions(+), 6 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 05fe5ba32187..9aae11cb568e 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -169,6 +169,24 @@ struct receive_queue {
 	struct xdp_rxq_info xdp_rxq;
 };
 
+/* This structure can contain rss message with maximum settings for indirection table and keysize
+ * Note, that default structure that describes RSS configuration virtio_net_rss_config
+ * contains same info but can't handle table values.
+ * In any case, structure would be passed to virtio hw through sg_buf split by parts
+ * because table sizes may be differ according to the device configuration.
+ */
+#define VIRTIO_NET_RSS_MAX_KEY_SIZE     40
+#define VIRTIO_NET_RSS_MAX_TABLE_LEN    128
+struct virtio_net_ctrl_rss {
+	u32 hash_types;
+	u16 indirection_table_mask;
+	u16 unclassified_queue;
+	u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN];
+	u16 max_tx_vq;
+	u8 hash_key_length;
+	u8 key[VIRTIO_NET_RSS_MAX_KEY_SIZE];
+};
+
 /* Control VQ buffers: protected by the rtnl lock */
 struct control_buf {
 	struct virtio_net_ctrl_hdr hdr;
@@ -178,6 +196,7 @@ struct control_buf {
 	u8 allmulti;
 	__virtio16 vid;
 	__virtio64 offloads;
+	struct virtio_net_ctrl_rss rss;
 };
 
 struct virtnet_info {
@@ -206,6 +225,12 @@ struct virtnet_info {
 	/* Host will merge rx buffers for big packets (shake it! shake it!) */
 	bool mergeable_rx_bufs;
 
+	/* Host supports rss and/or hash report */
+	bool has_rss;
+	u8 rss_key_size;
+	u16 rss_indir_table_size;
+	u32 rss_hash_types_supported;
+
 	/* Has control virtqueue */
 	bool has_cvq;
 
@@ -2184,6 +2209,56 @@ static void virtnet_get_ringparam(struct net_device *dev,
 	ring->tx_pending = ring->tx_max_pending;
 }
 
+static bool virtnet_commit_rss_command(struct virtnet_info *vi)
+{
+	struct net_device *dev = vi->dev;
+	struct scatterlist sgs[4];
+	unsigned int sg_buf_size;
+
+	/* prepare sgs */
+	sg_init_table(sgs, 4);
+
+	sg_buf_size = offsetof(struct virtio_net_ctrl_rss, indirection_table);
+	sg_set_buf(&sgs[0], &vi->ctrl->rss, sg_buf_size);
+
+	sg_buf_size = sizeof(uint16_t) * vi->rss_indir_table_size;
+	sg_set_buf(&sgs[1], vi->ctrl->rss.indirection_table, sg_buf_size);
+
+	sg_buf_size = offsetof(struct virtio_net_ctrl_rss, key)
+			- offsetof(struct virtio_net_ctrl_rss, max_tx_vq);
+	sg_set_buf(&sgs[2], &vi->ctrl->rss.max_tx_vq, sg_buf_size);
+
+	sg_buf_size = vi->rss_key_size;
+	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)) {
+		dev_warn(&dev->dev, "VIRTIONET issue with committing RSS sgs\n");
+		return false;
+	}
+	return true;
+}
+
+static void virtnet_init_default_rss(struct virtnet_info *vi)
+{
+	u32 indir_val = 0;
+	int i = 0;
+
+	vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
+	vi->ctrl->rss.indirection_table_mask = vi->rss_indir_table_size - 1;
+	vi->ctrl->rss.unclassified_queue = 0;
+
+	for (; i < vi->rss_indir_table_size; ++i) {
+		indir_val = ethtool_rxfh_indir_default(i, vi->curr_queue_pairs);
+		vi->ctrl->rss.indirection_table[i] = indir_val;
+	}
+
+	vi->ctrl->rss.max_tx_vq = vi->curr_queue_pairs;
+	vi->ctrl->rss.hash_key_length = vi->rss_key_size;
+
+	netdev_rss_key_fill(vi->ctrl->rss.key, vi->rss_key_size);
+}
+
 
 static void virtnet_get_drvinfo(struct net_device *dev,
 				struct ethtool_drvinfo *info)
@@ -2412,6 +2487,71 @@ static void virtnet_update_settings(struct virtnet_info *vi)
 		vi->duplex = duplex;
 }
 
+static u32 virtnet_get_rxfh_key_size(struct net_device *dev)
+{
+	return ((struct virtnet_info *)netdev_priv(dev))->rss_key_size;
+}
+
+static u32 virtnet_get_rxfh_indir_size(struct net_device *dev)
+{
+	return ((struct virtnet_info *)netdev_priv(dev))->rss_indir_table_size;
+}
+
+static int virtnet_get_rxfh(struct net_device *dev, u32 *indir, u8 *key, u8 *hfunc)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int i;
+
+	if (indir) {
+		for (i = 0; i < vi->rss_indir_table_size; ++i)
+			indir[i] = vi->ctrl->rss.indirection_table[i];
+	}
+
+	if (key)
+		memcpy(key, vi->ctrl->rss.key, vi->rss_key_size);
+
+	if (hfunc)
+		*hfunc = ETH_RSS_HASH_TOP;
+
+	return 0;
+}
+
+static int virtnet_set_rxfh(struct net_device *dev, const u32 *indir, const u8 *key, const u8 hfunc)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int i;
+
+	if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
+		return -EOPNOTSUPP;
+
+	if (indir) {
+		for (i = 0; i < vi->rss_indir_table_size; ++i)
+			vi->ctrl->rss.indirection_table[i] = indir[i];
+	}
+	if (key)
+		memcpy(vi->ctrl->rss.key, key, vi->rss_key_size);
+
+	virtnet_commit_rss_command(vi);
+
+	return 0;
+}
+
+static int virtnet_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info, u32 *rule_locs)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int rc = 0;
+
+	switch (info->cmd) {
+	case ETHTOOL_GRXRINGS:
+		info->data = vi->curr_queue_pairs;
+		break;
+	default:
+		rc = -EOPNOTSUPP;
+	}
+
+	return rc;
+}
+
 static const struct ethtool_ops virtnet_ethtool_ops = {
 	.supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES,
 	.get_drvinfo = virtnet_get_drvinfo,
@@ -2427,6 +2567,11 @@ static const struct ethtool_ops virtnet_ethtool_ops = {
 	.set_link_ksettings = virtnet_set_link_ksettings,
 	.set_coalesce = virtnet_set_coalesce,
 	.get_coalesce = virtnet_get_coalesce,
+	.get_rxfh_key_size = virtnet_get_rxfh_key_size,
+	.get_rxfh_indir_size = virtnet_get_rxfh_indir_size,
+	.get_rxfh = virtnet_get_rxfh,
+	.set_rxfh = virtnet_set_rxfh,
+	.get_rxnfc = virtnet_get_rxnfc,
 };
 
 static void virtnet_freeze_down(struct virtio_device *vdev)
@@ -2679,6 +2824,16 @@ 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.hash_types = vi->rss_hash_types_supported;
+		else
+			vi->ctrl->rss.hash_types = VIRTIO_NET_HASH_REPORT_NONE;
+
+		if (!virtnet_commit_rss_command(vi))
+			return -EINVAL;
+	}
+
 	return 0;
 }
 
@@ -3073,6 +3228,8 @@ static bool virtnet_validate_features(struct virtio_device *vdev)
 			     "VIRTIO_NET_F_CTRL_VQ") ||
 	     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_CTRL_VQ"))) {
 		return false;
 	}
@@ -3113,13 +3270,14 @@ static int virtnet_probe(struct virtio_device *vdev)
 	u16 max_queue_pairs;
 	int mtu;
 
-	/* Find if host supports multiqueue virtio_net device */
-	err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
-				   struct virtio_net_config,
-				   max_virtqueue_pairs, &max_queue_pairs);
+	/* Find if host supports multiqueue/rss virtio_net device */
+	max_queue_pairs = 0;
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_MQ) || virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
+		max_queue_pairs =
+		     virtio_cread16(vdev, offsetof(struct virtio_net_config, max_virtqueue_pairs));
 
 	/* We need at least 2 queue's */
-	if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
+	if (max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
 	    max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
 	    !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
 		max_queue_pairs = 1;
@@ -3207,6 +3365,25 @@ 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_RSS)) {
+		vi->has_rss = true;
+		vi->rss_indir_table_size =
+			virtio_cread16(vdev, offsetof(struct virtio_net_config,
+						      rss_max_indirection_table_length));
+		vi->rss_key_size =
+			virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size));
+	}
+
+	if (vi->has_rss) {
+		vi->rss_hash_types_supported =
+		    virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types));
+		vi->rss_hash_types_supported &=
+				~(VIRTIO_NET_RSS_HASH_TYPE_IP_EX |
+				  VIRTIO_NET_RSS_HASH_TYPE_TCP_EX |
+				  VIRTIO_NET_RSS_HASH_TYPE_UDP_EX);
+
+		dev->hw_features |= NETIF_F_RXHASH;
+	}
 	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);
@@ -3275,6 +3452,9 @@ static int virtnet_probe(struct virtio_device *vdev)
 		}
 	}
 
+	if (vi->has_rss)
+		virtnet_init_default_rss(vi);
+
 	err = register_netdev(dev);
 	if (err) {
 		pr_debug("virtio_net: registering device failed\n");
@@ -3406,7 +3586,8 @@ static struct virtio_device_id id_table[] = {
 	VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
 	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_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \
+	VIRTIO_NET_F_RSS
 
 static unsigned int features[] = {
 	VIRTNET_FEATURES,
-- 
2.34.1

Re: [PATCH v2 2/4] drivers/net/virtio_net: Added basic RSS support.

[Jason Wang]

在 2022/1/17 下午4:00, Andrew Melnychenko 写道:
> Added features for RSS.
> Added initialization, RXHASH feature and ethtool ops.
> By default RSS/RXHASH is disabled.
> Virtio RSS "IPv6 extensions" hashes disabled.
> Added ethtools ops to set key and indirection table.
>
> Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
> ---
>   drivers/net/virtio_net.c | 193 +++++++++++++++++++++++++++++++++++++--
>   1 file changed, 187 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 05fe5ba32187..9aae11cb568e 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -169,6 +169,24 @@ struct receive_queue {
>   	struct xdp_rxq_info xdp_rxq;
>   };
>   
> +/* This structure can contain rss message with maximum settings for indirection table and keysize
> + * Note, that default structure that describes RSS configuration virtio_net_rss_config
> + * contains same info but can't handle table values.
> + * In any case, structure would be passed to virtio hw through sg_buf split by parts
> + * because table sizes may be differ according to the device configuration.
> + */
> +#define VIRTIO_NET_RSS_MAX_KEY_SIZE     40
> +#define VIRTIO_NET_RSS_MAX_TABLE_LEN    128
> +struct virtio_net_ctrl_rss {
> +	u32 hash_types;
> +	u16 indirection_table_mask;
> +	u16 unclassified_queue;
> +	u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN];
> +	u16 max_tx_vq;
> +	u8 hash_key_length;
> +	u8 key[VIRTIO_NET_RSS_MAX_KEY_SIZE];
> +};
> +
>   /* Control VQ buffers: protected by the rtnl lock */
>   struct control_buf {
>   	struct virtio_net_ctrl_hdr hdr;
> @@ -178,6 +196,7 @@ struct control_buf {
>   	u8 allmulti;
>   	__virtio16 vid;
>   	__virtio64 offloads;
> +	struct virtio_net_ctrl_rss rss;
>   };
>   
>   struct virtnet_info {
> @@ -206,6 +225,12 @@ struct virtnet_info {
>   	/* Host will merge rx buffers for big packets (shake it! shake it!) */
>   	bool mergeable_rx_bufs;
>   
> +	/* Host supports rss and/or hash report */
> +	bool has_rss;
> +	u8 rss_key_size;
> +	u16 rss_indir_table_size;
> +	u32 rss_hash_types_supported;
> +
>   	/* Has control virtqueue */
>   	bool has_cvq;
>   
> @@ -2184,6 +2209,56 @@ static void virtnet_get_ringparam(struct net_device *dev,
>   	ring->tx_pending = ring->tx_max_pending;
>   }
>   
> +static bool virtnet_commit_rss_command(struct virtnet_info *vi)
> +{
> +	struct net_device *dev = vi->dev;
> +	struct scatterlist sgs[4];
> +	unsigned int sg_buf_size;
> +
> +	/* prepare sgs */
> +	sg_init_table(sgs, 4);
> +
> +	sg_buf_size = offsetof(struct virtio_net_ctrl_rss, indirection_table);
> +	sg_set_buf(&sgs[0], &vi->ctrl->rss, sg_buf_size);
> +
> +	sg_buf_size = sizeof(uint16_t) * vi->rss_indir_table_size;
> +	sg_set_buf(&sgs[1], vi->ctrl->rss.indirection_table, sg_buf_size);
> +
> +	sg_buf_size = offsetof(struct virtio_net_ctrl_rss, key)
> +			- offsetof(struct virtio_net_ctrl_rss, max_tx_vq);
> +	sg_set_buf(&sgs[2], &vi->ctrl->rss.max_tx_vq, sg_buf_size);
> +
> +	sg_buf_size = vi->rss_key_size;
> +	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)) {
> +		dev_warn(&dev->dev, "VIRTIONET issue with committing RSS sgs\n");
> +		return false;
> +	}
> +	return true;
> +}
> +
> +static void virtnet_init_default_rss(struct virtnet_info *vi)
> +{
> +	u32 indir_val = 0;
> +	int i = 0;
> +
> +	vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
> +	vi->ctrl->rss.indirection_table_mask = vi->rss_indir_table_size - 1;
> +	vi->ctrl->rss.unclassified_queue = 0;
> +
> +	for (; i < vi->rss_indir_table_size; ++i) {
> +		indir_val = ethtool_rxfh_indir_default(i, vi->curr_queue_pairs);
> +		vi->ctrl->rss.indirection_table[i] = indir_val;
> +	}
> +
> +	vi->ctrl->rss.max_tx_vq = vi->curr_queue_pairs;
> +	vi->ctrl->rss.hash_key_length = vi->rss_key_size;
> +
> +	netdev_rss_key_fill(vi->ctrl->rss.key, vi->rss_key_size);
> +}
> +
>   
>   static void virtnet_get_drvinfo(struct net_device *dev,
>   				struct ethtool_drvinfo *info)
> @@ -2412,6 +2487,71 @@ static void virtnet_update_settings(struct virtnet_info *vi)
>   		vi->duplex = duplex;
>   }
>   
> +static u32 virtnet_get_rxfh_key_size(struct net_device *dev)
> +{
> +	return ((struct virtnet_info *)netdev_priv(dev))->rss_key_size;
> +}
> +
> +static u32 virtnet_get_rxfh_indir_size(struct net_device *dev)
> +{
> +	return ((struct virtnet_info *)netdev_priv(dev))->rss_indir_table_size;
> +}
> +
> +static int virtnet_get_rxfh(struct net_device *dev, u32 *indir, u8 *key, u8 *hfunc)
> +{
> +	struct virtnet_info *vi = netdev_priv(dev);
> +	int i;
> +
> +	if (indir) {
> +		for (i = 0; i < vi->rss_indir_table_size; ++i)
> +			indir[i] = vi->ctrl->rss.indirection_table[i];
> +	}
> +
> +	if (key)
> +		memcpy(key, vi->ctrl->rss.key, vi->rss_key_size);
> +
> +	if (hfunc)
> +		*hfunc = ETH_RSS_HASH_TOP;
> +
> +	return 0;
> +}
> +
> +static int virtnet_set_rxfh(struct net_device *dev, const u32 *indir, const u8 *key, const u8 hfunc)
> +{
> +	struct virtnet_info *vi = netdev_priv(dev);
> +	int i;
> +
> +	if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
> +		return -EOPNOTSUPP;
> +
> +	if (indir) {
> +		for (i = 0; i < vi->rss_indir_table_size; ++i)
> +			vi->ctrl->rss.indirection_table[i] = indir[i];
> +	}
> +	if (key)
> +		memcpy(vi->ctrl->rss.key, key, vi->rss_key_size);
> +
> +	virtnet_commit_rss_command(vi);
> +
> +	return 0;
> +}
> +
> +static int virtnet_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info, u32 *rule_locs)
> +{
> +	struct virtnet_info *vi = netdev_priv(dev);
> +	int rc = 0;
> +
> +	switch (info->cmd) {
> +	case ETHTOOL_GRXRINGS:
> +		info->data = vi->curr_queue_pairs;
> +		break;
> +	default:
> +		rc = -EOPNOTSUPP;
> +	}
> +
> +	return rc;
> +}
> +
>   static const struct ethtool_ops virtnet_ethtool_ops = {
>   	.supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES,
>   	.get_drvinfo = virtnet_get_drvinfo,
> @@ -2427,6 +2567,11 @@ static const struct ethtool_ops virtnet_ethtool_ops = {
>   	.set_link_ksettings = virtnet_set_link_ksettings,
>   	.set_coalesce = virtnet_set_coalesce,
>   	.get_coalesce = virtnet_get_coalesce,
> +	.get_rxfh_key_size = virtnet_get_rxfh_key_size,
> +	.get_rxfh_indir_size = virtnet_get_rxfh_indir_size,
> +	.get_rxfh = virtnet_get_rxfh,
> +	.set_rxfh = virtnet_set_rxfh,
> +	.get_rxnfc = virtnet_get_rxnfc,
>   };
>   
>   static void virtnet_freeze_down(struct virtio_device *vdev)
> @@ -2679,6 +2824,16 @@ 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.hash_types = vi->rss_hash_types_supported;
> +		else
> +			vi->ctrl->rss.hash_types = VIRTIO_NET_HASH_REPORT_NONE;
> +
> +		if (!virtnet_commit_rss_command(vi))
> +			return -EINVAL;
> +	}
> +
>   	return 0;
>   }
>   
> @@ -3073,6 +3228,8 @@ static bool virtnet_validate_features(struct virtio_device *vdev)
>   			     "VIRTIO_NET_F_CTRL_VQ") ||
>   	     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_CTRL_VQ"))) {
>   		return false;
>   	}
> @@ -3113,13 +3270,14 @@ static int virtnet_probe(struct virtio_device *vdev)
>   	u16 max_queue_pairs;
>   	int mtu;
>   
> -	/* Find if host supports multiqueue virtio_net device */
> -	err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
> -				   struct virtio_net_config,
> -				   max_virtqueue_pairs, &max_queue_pairs);
> +	/* Find if host supports multiqueue/rss virtio_net device */
> +	max_queue_pairs = 0;


Do we need to initialize this to 1? Otherwise we won't pass the below 
check against VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN.


> +	if (virtio_has_feature(vdev, VIRTIO_NET_F_MQ) || virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
> +		max_queue_pairs =
> +		     virtio_cread16(vdev, offsetof(struct virtio_net_config, max_virtqueue_pairs));
>   
>   	/* We need at least 2 queue's */
> -	if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
> +	if (max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
>   	    max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
>   	    !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
>   		max_queue_pairs = 1;
> @@ -3207,6 +3365,25 @@ 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_RSS)) {
> +		vi->has_rss = true;
> +		vi->rss_indir_table_size =
> +			virtio_cread16(vdev, offsetof(struct virtio_net_config,
> +						      rss_max_indirection_table_length));
> +		vi->rss_key_size =
> +			virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size));
> +	}
> +
> +	if (vi->has_rss) {


We don't need this check, we can simple reuse the above one.


Thanks


> +		vi->rss_hash_types_supported =
> +		    virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types));
> +		vi->rss_hash_types_supported &=
> +				~(VIRTIO_NET_RSS_HASH_TYPE_IP_EX |
> +				  VIRTIO_NET_RSS_HASH_TYPE_TCP_EX |
> +				  VIRTIO_NET_RSS_HASH_TYPE_UDP_EX);
> +
> +		dev->hw_features |= NETIF_F_RXHASH;
> +	}
>   	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);
> @@ -3275,6 +3452,9 @@ static int virtnet_probe(struct virtio_device *vdev)
>   		}
>   	}
>   
> +	if (vi->has_rss)
> +		virtnet_init_default_rss(vi);
> +
>   	err = register_netdev(dev);
>   	if (err) {
>   		pr_debug("virtio_net: registering device failed\n");
> @@ -3406,7 +3586,8 @@ static struct virtio_device_id id_table[] = {
>   	VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
>   	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_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \
> +	VIRTIO_NET_F_RSS
>   
>   static unsigned int features[] = {
>   	VIRTNET_FEATURES,

[PATCH v2 3/4] drivers/net/virtio_net: Added RSS hash report.

[Andrew Melnychenko]

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 | 58 ++++++++++++++++++++++++++++++++--------
 1 file changed, 47 insertions(+), 11 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 9aae11cb568e..2c61f96ce3e6 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -227,6 +227,7 @@ 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;
@@ -420,7 +421,9 @@ 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);
@@ -1156,6 +1159,8 @@ 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);
@@ -1182,6 +1187,29 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
 		return;
 
 	hdr = skb_vnet_hdr(skb);
+	if (dev->features & NETIF_F_RXHASH && vi->has_rss_hash_report) {
+		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;
@@ -2232,7 +2260,8 @@ 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;
 	}
@@ -3230,6 +3259,8 @@ static bool virtnet_validate_features(struct virtio_device *vdev)
 	     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_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT,
 			     "VIRTIO_NET_F_CTRL_VQ"))) {
 		return false;
 	}
@@ -3365,16 +3396,18 @@ 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_RSS)) {
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT))
+		vi->has_rss_hash_report = true;
+
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
 		vi->has_rss = true;
+
+	if (vi->has_rss || vi->has_rss_hash_report) {
 		vi->rss_indir_table_size =
 			virtio_cread16(vdev, offsetof(struct virtio_net_config,
-						      rss_max_indirection_table_length));
+					rss_max_indirection_table_length));
 		vi->rss_key_size =
 			virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size));
-	}
-
-	if (vi->has_rss) {
 		vi->rss_hash_types_supported =
 		    virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types));
 		vi->rss_hash_types_supported &=
@@ -3384,8 +3417,11 @@ 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);
@@ -3452,7 +3488,7 @@ static int virtnet_probe(struct virtio_device *vdev)
 		}
 	}
 
-	if (vi->has_rss)
+	if (vi->has_rss || vi->has_rss_hash_report)
 		virtnet_init_default_rss(vi);
 
 	err = register_netdev(dev);
@@ -3587,7 +3623,7 @@ 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,
-- 
2.34.1

Re: [PATCH v2 3/4] drivers/net/virtio_net: Added RSS hash report.

[Jason Wang]

在 2022/1/17 下午4:00, 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 | 58 ++++++++++++++++++++++++++++++++--------
>   1 file changed, 47 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 9aae11cb568e..2c61f96ce3e6 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -227,6 +227,7 @@ 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;
> @@ -420,7 +421,9 @@ 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);


This seems wrong, add_recvbuf_big() will always try to use sizeof(struct 
padded_vnet_hdr).

This can be tested by disabling mrg_rxbuf.


> +	else if (vi->mergeable_rx_bufs)
>   		hdr_padded_len = sizeof(*hdr);
>   	else
>   		hdr_padded_len = sizeof(struct padded_vnet_hdr);
> @@ -1156,6 +1159,8 @@ 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);
> @@ -1182,6 +1187,29 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
>   		return;
>   
>   	hdr = skb_vnet_hdr(skb);
> +	if (dev->features & NETIF_F_RXHASH && vi->has_rss_hash_report) {
> +		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;
> @@ -2232,7 +2260,8 @@ 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;
>   	}
> @@ -3230,6 +3259,8 @@ static bool virtnet_validate_features(struct virtio_device *vdev)
>   	     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_CTRL_VQ") ||
> +	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT,
>   			     "VIRTIO_NET_F_CTRL_VQ"))) {
>   		return false;
>   	}
> @@ -3365,16 +3396,18 @@ 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_RSS)) {
> +	if (virtio_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT))
> +		vi->has_rss_hash_report = true;
> +
> +	if (virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
>   		vi->has_rss = true;
> +
> +	if (vi->has_rss || vi->has_rss_hash_report) {
>   		vi->rss_indir_table_size =
>   			virtio_cread16(vdev, offsetof(struct virtio_net_config,
> -						      rss_max_indirection_table_length));
> +					rss_max_indirection_table_length));


Unnecessary changes.


>   		vi->rss_key_size =
>   			virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size));
> -	}
> -
> -	if (vi->has_rss) {


This can be squashed into previous patch.

Thanks


>   		vi->rss_hash_types_supported =
>   		    virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types));
>   		vi->rss_hash_types_supported &=
> @@ -3384,8 +3417,11 @@ 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);
> @@ -3452,7 +3488,7 @@ static int virtnet_probe(struct virtio_device *vdev)
>   		}
>   	}
>   
> -	if (vi->has_rss)
> +	if (vi->has_rss || vi->has_rss_hash_report)
>   		virtnet_init_default_rss(vi);
>   
>   	err = register_netdev(dev);
> @@ -3587,7 +3623,7 @@ 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,

[PATCH v2 4/4] drivers/net/virtio_net: Added RSS hash report control.

[Andrew Melnychenko]

Now it's possible to control supported hashflows.
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 | 141 ++++++++++++++++++++++++++++++++++++++-
 1 file changed, 140 insertions(+), 1 deletion(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 2c61f96ce3e6..f837d3257eb6 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -231,6 +231,7 @@ 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;
@@ -2274,6 +2275,7 @@ static void virtnet_init_default_rss(struct virtnet_info *vi)
 	int i = 0;
 
 	vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
+	vi->rss_hash_types_saved = vi->rss_hash_types_supported;
 	vi->ctrl->rss.indirection_table_mask = vi->rss_indir_table_size - 1;
 	vi->ctrl->rss.unclassified_queue = 0;
 
@@ -2288,6 +2290,121 @@ 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_IPv6)
+			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)
+{
+	u32 new_hashtypes = vi->rss_hash_types_saved;
+	bool is_disable = info->data & RXH_DISCARD;
+	bool is_l4 = info->data == (RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3);
+
+	/* supports only 'sd', 'sdfn' and 'r' */
+	if (!((info->data == (RXH_IP_SRC | RXH_IP_DST)) | is_l4 | is_disable))
+		return false;
+
+	switch (info->flow_type) {
+	case TCP_V4_FLOW:
+		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_TCPv4);
+		if (!is_disable)
+			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
+				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv4 : 0);
+		break;
+	case UDP_V4_FLOW:
+		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_UDPv4);
+		if (!is_disable)
+			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
+				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv4 : 0);
+		break;
+	case IPV4_FLOW:
+		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv4;
+		if (!is_disable)
+			new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv4;
+		break;
+	case TCP_V6_FLOW:
+		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_TCPv6);
+		if (!is_disable)
+			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
+				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv6 : 0);
+		break;
+	case UDP_V6_FLOW:
+		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_UDPv6);
+		if (!is_disable)
+			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
+				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv6 : 0);
+		break;
+	case IPV6_FLOW:
+		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv6;
+		if (!is_disable)
+			new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv6;
+		break;
+	default:
+		/* unsupported flow */
+		return false;
+	}
+
+	/* if unsupported hashtype was set */
+	if (new_hashtypes != (new_hashtypes & vi->rss_hash_types_supported))
+		return false;
+
+	if (new_hashtypes != vi->rss_hash_types_saved) {
+		vi->rss_hash_types_saved = new_hashtypes;
+		vi->ctrl->rss.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)
@@ -2573,6 +2690,27 @@ 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;
@@ -2601,6 +2739,7 @@ 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)
@@ -2855,7 +2994,7 @@ static int virtnet_set_features(struct net_device *dev,
 
 	if ((dev->features ^ features) & NETIF_F_RXHASH) {
 		if (features & NETIF_F_RXHASH)
-			vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
+			vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
 		else
 			vi->ctrl->rss.hash_types = VIRTIO_NET_HASH_REPORT_NONE;
 
-- 
2.34.1

Re: [PATCH v2 4/4] drivers/net/virtio_net: Added RSS hash report control.

[Jason Wang]

在 2022/1/17 下午4:00, Andrew Melnychenko 写道:
> Now it's possible to control supported hashflows.
> 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>


Acked-by: Jason Wang <jasowang@redhat.com>


> ---
>   drivers/net/virtio_net.c | 141 ++++++++++++++++++++++++++++++++++++++-
>   1 file changed, 140 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 2c61f96ce3e6..f837d3257eb6 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -231,6 +231,7 @@ 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;
> @@ -2274,6 +2275,7 @@ static void virtnet_init_default_rss(struct virtnet_info *vi)
>   	int i = 0;
>   
>   	vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
> +	vi->rss_hash_types_saved = vi->rss_hash_types_supported;
>   	vi->ctrl->rss.indirection_table_mask = vi->rss_indir_table_size - 1;
>   	vi->ctrl->rss.unclassified_queue = 0;
>   
> @@ -2288,6 +2290,121 @@ 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_IPv6)
> +			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)
> +{
> +	u32 new_hashtypes = vi->rss_hash_types_saved;
> +	bool is_disable = info->data & RXH_DISCARD;
> +	bool is_l4 = info->data == (RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3);
> +
> +	/* supports only 'sd', 'sdfn' and 'r' */
> +	if (!((info->data == (RXH_IP_SRC | RXH_IP_DST)) | is_l4 | is_disable))
> +		return false;
> +
> +	switch (info->flow_type) {
> +	case TCP_V4_FLOW:
> +		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_TCPv4);
> +		if (!is_disable)
> +			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
> +				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv4 : 0);
> +		break;
> +	case UDP_V4_FLOW:
> +		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_UDPv4);
> +		if (!is_disable)
> +			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
> +				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv4 : 0);
> +		break;
> +	case IPV4_FLOW:
> +		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv4;
> +		if (!is_disable)
> +			new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv4;
> +		break;
> +	case TCP_V6_FLOW:
> +		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_TCPv6);
> +		if (!is_disable)
> +			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
> +				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv6 : 0);
> +		break;
> +	case UDP_V6_FLOW:
> +		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_UDPv6);
> +		if (!is_disable)
> +			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
> +				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv6 : 0);
> +		break;
> +	case IPV6_FLOW:
> +		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv6;
> +		if (!is_disable)
> +			new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv6;
> +		break;
> +	default:
> +		/* unsupported flow */
> +		return false;
> +	}
> +
> +	/* if unsupported hashtype was set */
> +	if (new_hashtypes != (new_hashtypes & vi->rss_hash_types_supported))
> +		return false;
> +
> +	if (new_hashtypes != vi->rss_hash_types_saved) {
> +		vi->rss_hash_types_saved = new_hashtypes;
> +		vi->ctrl->rss.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)
> @@ -2573,6 +2690,27 @@ 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;
> @@ -2601,6 +2739,7 @@ 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)
> @@ -2855,7 +2994,7 @@ static int virtnet_set_features(struct net_device *dev,
>   
>   	if ((dev->features ^ features) & NETIF_F_RXHASH) {
>   		if (features & NETIF_F_RXHASH)
> -			vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
> +			vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
>   		else
>   			vi->ctrl->rss.hash_types = VIRTIO_NET_HASH_REPORT_NONE;
>