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

From: Andrew Melnichenko
Date: Mon Jan 17 2022 - 02:59:01 EST


Hi all,

> e.g RXH_VLAN with port hash?
> Any way to merge the two switch? The code is hard to be reviewed anyhow.
I'll refactor virtnet_set_hashflow.

> I think it's better to use VIRTIO_NET_HASH_REPORT_NONE here.
Yes, I'll fix that.

On Tue, Jan 11, 2022 at 6:33 AM Jason Wang <jasowang@xxxxxxxxxx> wrote:
>
>
> 在 2022/1/10 上午5:06, Andrew Melnychenko 写道:
> > Now it's possible to control supported hashflows.
> > Also added hashflow set/get callbacks.
> > Also, disabling RXH_IP_SRC/DST for TCP would disable then for UDP.
> > TCP and UDP supports only:
> > ethtool -U eth0 rx-flow-hash tcp4 sd
> > RXH_IP_SRC + RXH_IP_DST
> > ethtool -U eth0 rx-flow-hash tcp4 sdfn
> > RXH_IP_SRC + RXH_IP_DST + RXH_L4_B_0_1 + RXH_L4_B_2_3
> >
> > Signed-off-by: Andrew Melnychenko <andrew@xxxxxxxxxx>
> > ---
> > drivers/net/virtio_net.c | 159 +++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 159 insertions(+)
> >
> > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > index 6e7461b01f87..1b8dd384483c 100644
> > --- a/drivers/net/virtio_net.c
> > +++ b/drivers/net/virtio_net.c
> > @@ -235,6 +235,7 @@ struct virtnet_info {
> > u8 rss_key_size;
> > u16 rss_indir_table_size;
> > u32 rss_hash_types_supported;
> > + u32 rss_hash_types_saved;
> >
> > /* Has control virtqueue */
> > bool has_cvq;
> > @@ -2275,6 +2276,7 @@ static void virtnet_init_default_rss(struct virtnet_info *vi)
> > int i = 0;
> >
> > vi->ctrl->rss.table_info.hash_types = vi->rss_hash_types_supported;
> > + vi->rss_hash_types_saved = vi->rss_hash_types_supported;
> > vi->ctrl->rss.table_info.indirection_table_mask = vi->rss_indir_table_size - 1;
> > vi->ctrl->rss.table_info.unclassified_queue = 0;
> >
> > @@ -2289,6 +2291,131 @@ static void virtnet_init_default_rss(struct virtnet_info *vi)
> > netdev_rss_key_fill(vi->ctrl->rss.key, vi->rss_key_size);
> > }
> >
> > +static void virtnet_get_hashflow(const struct virtnet_info *vi, struct ethtool_rxnfc *info)
> > +{
> > + info->data = 0;
> > + switch (info->flow_type) {
> > + case TCP_V4_FLOW:
> > + if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv4) {
> > + info->data = RXH_IP_SRC | RXH_IP_DST |
> > + RXH_L4_B_0_1 | RXH_L4_B_2_3;
> > + } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
> > + info->data = RXH_IP_SRC | RXH_IP_DST;
> > + }
> > + break;
> > + case TCP_V6_FLOW:
> > + if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv6) {
> > + info->data = RXH_IP_SRC | RXH_IP_DST |
> > + RXH_L4_B_0_1 | RXH_L4_B_2_3;
> > + } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
> > + info->data = RXH_IP_SRC | RXH_IP_DST;
> > + }
> > + break;
> > + case UDP_V4_FLOW:
> > + if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv4) {
> > + info->data = RXH_IP_SRC | RXH_IP_DST |
> > + RXH_L4_B_0_1 | RXH_L4_B_2_3;
> > + } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
> > + info->data = RXH_IP_SRC | RXH_IP_DST;
> > + }
> > + break;
> > + case UDP_V6_FLOW:
> > + if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv6) {
> > + info->data = RXH_IP_SRC | RXH_IP_DST |
> > + RXH_L4_B_0_1 | RXH_L4_B_2_3;
> > + } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
> > + info->data = RXH_IP_SRC | RXH_IP_DST;
> > + }
> > + break;
> > + case IPV4_FLOW:
> > + if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4)
> > + info->data = RXH_IP_SRC | RXH_IP_DST;
> > +
> > + break;
> > + case IPV6_FLOW:
> > + if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4)
> > + info->data = RXH_IP_SRC | RXH_IP_DST;
> > +
> > + break;
> > + default:
> > + info->data = 0;
> > + break;
> > + }
> > +}
> > +
> > +static bool virtnet_set_hashflow(struct virtnet_info *vi, struct ethtool_rxnfc *info)
> > +{
> > + u64 is_iphash = info->data & (RXH_IP_SRC | RXH_IP_DST);
> > + u64 is_porthash = info->data & (RXH_L4_B_0_1 | RXH_L4_B_2_3);
> > + u32 new_hashtypes = vi->rss_hash_types_saved;
> > +
> > + if ((is_iphash && (is_iphash != (RXH_IP_SRC | RXH_IP_DST))) ||
> > + (is_porthash && (is_porthash != (RXH_L4_B_0_1 | RXH_L4_B_2_3)))) {
> > + return false;
> > + }
> > +
> > + if (!is_iphash && is_porthash)
> > + return false;
>
>
> This seems not filter out all the combinations:
>
> e.g RXH_VLAN with port hash?
>
>
> > +
> > + switch (info->flow_type) {
> > + case TCP_V4_FLOW:
> > + case UDP_V4_FLOW:
> > + case IPV4_FLOW:
> > + new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv4;
> > + if (is_iphash)
> > + new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4;
> > +
> > + break;
> > + case TCP_V6_FLOW:
> > + case UDP_V6_FLOW:
> > + case IPV6_FLOW:
> > + new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv6;
> > + if (is_iphash)
> > + new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6;
> > +
> > + break;
> > + default:
> > + break;
> > + }
> > +
> > + switch (info->flow_type) {
> > + case TCP_V4_FLOW:
> > + new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_TCPv4;
>
>
> Any way to merge the two switch? The code is hard to be reviewed anyhow.
>
>
> > + if (is_porthash)
> > + new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_TCPv4;
> > +
> > + break;
> > + case UDP_V4_FLOW:
> > + new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_UDPv4;
> > + if (is_porthash)
> > + new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_UDPv4;
> > +
> > + break;
> > + case TCP_V6_FLOW:
> > + new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_TCPv6;
> > + if (is_porthash)
> > + new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_TCPv6;
> > +
> > + break;
> > + case UDP_V6_FLOW:
> > + new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_UDPv6;
> > + if (is_porthash)
> > + new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_UDPv6;
> > +
> > + break;
> > + default:
> > + break;
> > + }
> > +
> > + if (new_hashtypes != vi->rss_hash_types_saved) {
> > + vi->rss_hash_types_saved = new_hashtypes;
> > + vi->ctrl->rss.table_info.hash_types = vi->rss_hash_types_saved;
> > + if (vi->dev->features & NETIF_F_RXHASH)
> > + return virtnet_commit_rss_command(vi);
> > + }
> > +
> > + return true;
> > +}
> >
> > static void virtnet_get_drvinfo(struct net_device *dev,
> > struct ethtool_drvinfo *info)
> > @@ -2574,6 +2701,27 @@ static int virtnet_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
> > switch (info->cmd) {
> > case ETHTOOL_GRXRINGS:
> > info->data = vi->curr_queue_pairs;
> > + break;
> > + case ETHTOOL_GRXFH:
> > + virtnet_get_hashflow(vi, info);
> > + break;
> > + default:
> > + rc = -EOPNOTSUPP;
> > + }
> > +
> > + return rc;
> > +}
> > +
> > +static int virtnet_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info)
> > +{
> > + struct virtnet_info *vi = netdev_priv(dev);
> > + int rc = 0;
> > +
> > + switch (info->cmd) {
> > + case ETHTOOL_SRXFH:
> > + if (!virtnet_set_hashflow(vi, info))
> > + rc = -EINVAL;
> > +
> > break;
> > default:
> > rc = -EOPNOTSUPP;
> > @@ -2602,6 +2750,7 @@ static const struct ethtool_ops virtnet_ethtool_ops = {
> > .get_rxfh = virtnet_get_rxfh,
> > .set_rxfh = virtnet_set_rxfh,
> > .get_rxnfc = virtnet_get_rxnfc,
> > + .set_rxnfc = virtnet_set_rxnfc,
> > };
> >
> > static void virtnet_freeze_down(struct virtio_device *vdev)
> > @@ -2854,6 +3003,16 @@ static int virtnet_set_features(struct net_device *dev,
> > vi->guest_offloads = offloads;
> > }
> >
> > + if ((dev->features ^ features) & NETIF_F_RXHASH) {
> > + if (features & NETIF_F_RXHASH)
> > + vi->ctrl->rss.table_info.hash_types = vi->rss_hash_types_saved;
> > + else
> > + vi->ctrl->rss.table_info.hash_types = 0;
>
>
> I think it's better to use VIRTIO_NET_HASH_REPORT_NONE here.
>
> Thanks
>
>
> > +
> > + if (!virtnet_commit_rss_command(vi))
> > + return -EINVAL;
> > + }
> > +
> > return 0;
> > }
> >
>