Andrew Melnychenko
2021-Oct-31  04:59 UTC
[RFC PATCH 3/4] drivers/net/virtio_net: Added basic RSS support.
Added features for RSS and RSS hash report.
Added initialization, RXHASH feature and ethtool ops.
By default RSS/RXHASH is disabled.
Added ethtools ops to set key and indirection table.
Signed-off-by: Andrew Melnychenko <andrew at daynix.com>
---
 drivers/net/virtio_net.c | 232 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 223 insertions(+), 9 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index abca2e93355d..cff7340f40bb 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -167,6 +167,28 @@ 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 {
+	struct {
+		__le32 hash_types;
+		__le16 indirection_table_mask;
+		__le16 unclassified_queue;
+	} __packed table_info;
+	u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN];
+	struct {
+		u16 max_tx_vq; /* queues */
+		u8 hash_key_length;
+	} __packed key_info;
+	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;
@@ -176,6 +198,7 @@ struct control_buf {
 	u8 allmulti;
 	__virtio16 vid;
 	__virtio64 offloads;
+	struct virtio_net_ctrl_rss rss;
 };
 
 struct virtnet_info {
@@ -204,6 +227,12 @@ 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;
+	bool has_rss_hash_report;
+	u8 rss_key_size;
+	u16 rss_indir_table_size;
+
 	/* Has control virtqueue */
 	bool has_cvq;
 
@@ -1119,6 +1148,8 @@ 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);
@@ -1145,6 +1176,29 @@ static void receive_buf(struct virtnet_info *vi, struct
receive_queue *rq,
 		return;
 
 	hdr = skb_vnet_hdr(skb);
+	if (vi->has_rss_hash_report && (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;
@@ -2167,6 +2221,57 @@ 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 = sizeof(vi->ctrl->rss.table_info);
+	sg_set_buf(&sgs[0], &vi->ctrl->rss.table_info, 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 = sizeof(vi->ctrl->rss.key_info);
+	sg_set_buf(&sgs[2], &vi->ctrl->rss.key_info, 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,
+				  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;
+	}
+	return true;
+}
+
+static void virtnet_init_default_rss(struct virtnet_info *vi)
+{
+	u32 indir_val = 0;
+	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;
+
+	for (; i < vi->rss_indir_table_size; ++i) {
+		indir_val = ethtool_rxfh_indir_default(i, vi->max_queue_pairs);
+		vi->ctrl->rss.indirection_table[i] = indir_val;
+	}
+
+	vi->ctrl->rss.key_info.max_tx_vq = vi->curr_queue_pairs;
+	vi->ctrl->rss.key_info.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)
@@ -2395,6 +2500,71 @@ 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,
@@ -2410,6 +2580,11 @@ 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)
@@ -3040,7 +3215,10 @@ 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"))) {
+			     "VIRTIO_NET_F_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS, "VIRTIO_NET_F_RSS") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT,
+			     "VIRTIO_NET_F_HASH_REPORT"))) {
 		return false;
 	}
 
@@ -3080,13 +3258,14 @@ 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;
@@ -3170,8 +3349,36 @@ 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_MRG_RXBUF) ||
-	    virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
+	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;
+	}
+
+	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->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 &+				~(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 (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);
@@ -3238,6 +3445,12 @@ static int virtnet_probe(struct virtio_device *vdev)
 		}
 	}
 
+	if (vi->has_rss || vi->has_rss_hash_report) {
+		rtnl_lock();
+		virtnet_init_default_rss(vi);
+		rtnl_unlock();
+	}
+
 	err = register_netdev(dev);
 	if (err) {
 		pr_debug("virtio_net: registering device failed\n");
@@ -3369,7 +3582,8 @@ 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, VIRTIO_NET_F_HASH_REPORT
 
 static unsigned int features[] = {
 	VIRTNET_FEATURES,
-- 
2.33.1
Willem de Bruijn
2021-Oct-31  15:32 UTC
[RFC PATCH 3/4] drivers/net/virtio_net: Added basic RSS support.
On Sun, Oct 31, 2021 at 1:00 AM Andrew Melnychenko <andrew at daynix.com> wrote:> > Added features for RSS and RSS hash report. > Added initialization, RXHASH feature and ethtool ops. > By default RSS/RXHASH is disabled. > Added ethtools ops to set key and indirection table. > > Signed-off-by: Andrew Melnychenko <andrew at daynix.com> > --- > drivers/net/virtio_net.c | 232 +++++++++++++++++++++++++++++++++++++-- > 1 file changed, 223 insertions(+), 9 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index abca2e93355d..cff7340f40bb 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -167,6 +167,28 @@ 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 40Unless there is a technical reason, this probably should be no shorter than TOEPLITZ_KEY_LEN> +#define VIRTIO_NET_RSS_MAX_TABLE_LEN 128 > +struct virtio_net_ctrl_rss { > + struct { > + __le32 hash_types; > + __le16 indirection_table_mask; > + __le16 unclassified_queue;Is this explicit variable needed?> + } __packed table_info; > + u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN]; > + struct { > + u16 max_tx_vq; /* queues */ > + u8 hash_key_length; > + } __packed key_info; > + 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; > @@ -176,6 +198,7 @@ struct control_buf { > u8 allmulti; > __virtio16 vid; > __virtio64 offloads; > + struct virtio_net_ctrl_rss rss; > }; > > struct virtnet_info { > @@ -204,6 +227,12 @@ 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;Superfluous, can be derived form non-zero rss_key_size?> + bool has_rss_hash_report; > + u8 rss_key_size; > + u16 rss_indir_table_size; > + > /* Has control virtqueue */ > bool has_cvq; > > @@ -1119,6 +1148,8 @@ 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); > @@ -1145,6 +1176,29 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq, > return; > > hdr = skb_vnet_hdr(skb); > + if (vi->has_rss_hash_report && (dev->features & NETIF_F_RXHASH)) {Only the second test is needed? It should be impossible to configure the feature unless the device advertises 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; > + }Is this detailed protocol typing necessary? Most devices only pass a bit is_l4.> + 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; > @@ -2167,6 +2221,57 @@ 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 = sizeof(vi->ctrl->rss.table_info); > + sg_set_buf(&sgs[0], &vi->ctrl->rss.table_info, 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 = sizeof(vi->ctrl->rss.key_info); > + sg_set_buf(&sgs[2], &vi->ctrl->rss.key_info, 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, > + 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; > + } > + return true; > +} > + > +static void virtnet_init_default_rss(struct virtnet_info *vi) > +{ > + u32 indir_val = 0; > + int i = 0; > + > + vi->ctrl->rss.table_info.hash_types = vi->rss_hash_types_supported;Similar to above, and related to the next patch: is this very detailed specification of supported hash types needed? When is this useful? It is not customary to specify RSS to that degree.> + 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; > + > + for (; i < vi->rss_indir_table_size; ++i) { > + indir_val = ethtool_rxfh_indir_default(i, vi->max_queue_pairs); > + vi->ctrl->rss.indirection_table[i] = indir_val; > + } > + > + vi->ctrl->rss.key_info.max_tx_vq = vi->curr_queue_pairs; > + vi->ctrl->rss.key_info.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) > @@ -2395,6 +2500,71 @@ 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, > @@ -2410,6 +2580,11 @@ 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) > @@ -3040,7 +3215,10 @@ 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"))) { > + "VIRTIO_NET_F_CTRL_VQ") || > + VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS, "VIRTIO_NET_F_RSS") || > + VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT, > + "VIRTIO_NET_F_HASH_REPORT"))) { > return false; > } > > @@ -3080,13 +3258,14 @@ 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))Is VIRTIO_NET_F_RSS implied by VIRTIO_NET_F_MQ?> + 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; > @@ -3170,8 +3349,36 @@ 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_MRG_RXBUF) || > - virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) > + 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; > + } > + > + 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)); > + }Please split adding the two features, hash report and rss, into two separate patches.
Andrew Melnichenko
2021-Nov-17  06:00 UTC
[RFC PATCH 3/4] drivers/net/virtio_net: Added basic RSS support.
On Sun, Oct 31, 2021 at 5:33 PM Willem de Bruijn <willemdebruijn.kernel at gmail.com> wrote:> > On Sun, Oct 31, 2021 at 1:00 AM Andrew Melnychenko <andrew at daynix.com> wrote: > > > > Added features for RSS and RSS hash report. > > Added initialization, RXHASH feature and ethtool ops. > > By default RSS/RXHASH is disabled. > > Added ethtools ops to set key and indirection table. > > > > Signed-off-by: Andrew Melnychenko <andrew at daynix.com> > > --- > > drivers/net/virtio_net.c | 232 +++++++++++++++++++++++++++++++++++++-- > > 1 file changed, 223 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > > index abca2e93355d..cff7340f40bb 100644 > > --- a/drivers/net/virtio_net.c > > +++ b/drivers/net/virtio_net.c > > @@ -167,6 +167,28 @@ 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 > > Unless there is a technical reason, this probably should be no shorter > than TOEPLITZ_KEY_LENWell yeah, technically if the device requests for shorter key, we still may provide it. I think we may check and 'disable' RSS if some configurations are inadequate.> > > +#define VIRTIO_NET_RSS_MAX_TABLE_LEN 128 > > +struct virtio_net_ctrl_rss { > > + struct { > > + __le32 hash_types; > > + __le16 indirection_table_mask; > > + __le16 unclassified_queue; > > Is this explicit variable needed?Yes, it's a part of the message to be sent to the device.> > > + } __packed table_info; > > + u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN]; > > + struct { > > + u16 max_tx_vq; /* queues */ > > + u8 hash_key_length; > > + } __packed key_info; > > + 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; > > @@ -176,6 +198,7 @@ struct control_buf { > > u8 allmulti; > > __virtio16 vid; > > __virtio64 offloads; > > + struct virtio_net_ctrl_rss rss; > > }; > > > > struct virtnet_info { > > @@ -204,6 +227,12 @@ 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; > > Superfluous, can be derived form non-zero rss_key_size?I think that the explicit 'has_rss' field is better. "non-zero rss_key_size" should work, I'll change RSS derivation in the next patches.> > > + bool has_rss_hash_report; > > + u8 rss_key_size; > > + u16 rss_indir_table_size; > > + > > /* Has control virtqueue */ > > bool has_cvq; > > > > @@ -1119,6 +1148,8 @@ 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); > > @@ -1145,6 +1176,29 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq, > > return; > > > > hdr = skb_vnet_hdr(skb); > > + if (vi->has_rss_hash_report && (dev->features & NETIF_F_RXHASH)) { > > Only the second test is needed? It should be impossible to configure > the feature unless the device advertises has_rss_hash_reportWell, you can have RSS without a hash population. So, need to check, is the device supports hash population and rxhash is enabled(g.e. through ethtool).> > > + 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; > > + } > > Is this detailed protocol typing necessary? Most devices only pass a bit is_l4.Yes, in theory, there is real hardware that may support only L3 hash calculations.> > > + 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; > > @@ -2167,6 +2221,57 @@ 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 = sizeof(vi->ctrl->rss.table_info); > > + sg_set_buf(&sgs[0], &vi->ctrl->rss.table_info, 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 = sizeof(vi->ctrl->rss.key_info); > > + sg_set_buf(&sgs[2], &vi->ctrl->rss.key_info, 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, > > + 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; > > + } > > + return true; > > +} > > + > > +static void virtnet_init_default_rss(struct virtnet_info *vi) > > +{ > > + u32 indir_val = 0; > > + int i = 0; > > + > > + vi->ctrl->rss.table_info.hash_types = vi->rss_hash_types_supported; > > Similar to above, and related to the next patch: is this very detailed > specification of supported hash types needed? When is this useful? It > is not customary to specify RSS to that degree.In theory, there are real devices that implement virtio_net with(or without) some supported hashes.> > > + 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; > > + > > + for (; i < vi->rss_indir_table_size; ++i) { > > + indir_val = ethtool_rxfh_indir_default(i, vi->max_queue_pairs); > > + vi->ctrl->rss.indirection_table[i] = indir_val; > > + } > > + > > + vi->ctrl->rss.key_info.max_tx_vq = vi->curr_queue_pairs; > > + vi->ctrl->rss.key_info.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) > > @@ -2395,6 +2500,71 @@ 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, > > @@ -2410,6 +2580,11 @@ 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) > > @@ -3040,7 +3215,10 @@ 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"))) { > > + "VIRTIO_NET_F_CTRL_VQ") || > > + VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS, "VIRTIO_NET_F_RSS") || > > + VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT, > > + "VIRTIO_NET_F_HASH_REPORT"))) { > > return false; > > } > > > > @@ -3080,13 +3258,14 @@ 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)) > > Is VIRTIO_NET_F_RSS implied by VIRTIO_NET_F_MQ?MQ and/or RSS sets multiqueue, like so:> virtio_net_set_multiqueue(n, > virtio_has_feature(features, VIRTIO_NET_F_RSS) || > virtio_has_feature(features, VIRTIO_NET_F_MQ));So, technically it's possible to create a virtual net only with RSS without mq.> > > + 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; > > @@ -3170,8 +3349,36 @@ 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_MRG_RXBUF) || > > - virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) > > + 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; > > + } > > + > > + 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)); > > + } > > Please split adding the two features, hash report and rss, into two > separate patches.It may provide dead code that will be replaced by code in 'hash report' report patch.