On Tue, Feb 8, 2022 at 1:19 PM Andrew Melnychenko <andrew@xxxxxxxxxx> wrote:
>
> 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@xxxxxxxxxx>
> ---
> drivers/net/virtio_net.c | 191 +++++++++++++++++++++++++++++++++++++--
> 1 file changed, 185 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 1404e683a2fd..495aed524e33 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
Future proof, may want to support larger sizes.
netdevice.h defines NETDEV_RSS_KEY_LEN at 52.
tools/testing/selftests/net/toeplitz.c supports up to 60
> +#define VIRTIO_NET_RSS_MAX_TABLE_LEN 128
> +struct virtio_net_ctrl_rss {
> + u32 hash_types;
conversely, u32 is a bit extreme?
> + 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;
Is table size always a power of two?
> + 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 = 1;
> + 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));
Instead of testing either feature and treating them as somewhat equal,
shouldn't RSS be dependent on MQ?
>
> /* 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 +3365,23 @@ 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));
> +
> + 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;
Only make the feature visible when the hash is actually reported in
the skb, patch 3.
Also, clearly separate the feature patches (2) rss, (3) rxhash, (4)
rxhash config.
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