* Re: [PATCH net-next v9] virtio_net: Support RX hash XDP hint
2024-04-17 7:18 [PATCH net-next v9] virtio_net: Support RX hash XDP hint Liang Chen
@ 2024-04-17 7:51 ` Jesper Dangaard Brouer
2024-04-17 7:59 ` Heng Qi
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Jesper Dangaard Brouer @ 2024-04-17 7:51 UTC (permalink / raw)
To: Liang Chen, mst, jasowang, xuanzhuo, hengqi, davem, edumazet,
kuba, pabeni, john.fastabend
Cc: netdev, virtualization, linux-kernel, bpf, daniel, ast
On 17/04/2024 09.18, Liang Chen wrote:
> The RSS hash report is a feature that's part of the virtio specification.
> Currently, virtio backends like qemu, vdpa (mlx5), and potentially vhost
> (still a work in progress as per [1]) support this feature. While the
> capability to obtain the RSS hash has been enabled in the normal path,
> it's currently missing in the XDP path. Therefore, we are introducing
> XDP hints through kfuncs to allow XDP programs to access the RSS hash.
>
> 1.
> https://lore.kernel.org/all/20231015141644.260646-1-akihiko.odaki@daynix.com/#r
>
> Signed-off-by: Liang Chen<liangchen.linux@gmail.com>
LGTM
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH net-next v9] virtio_net: Support RX hash XDP hint
2024-04-17 7:18 [PATCH net-next v9] virtio_net: Support RX hash XDP hint Liang Chen
2024-04-17 7:51 ` Jesper Dangaard Brouer
@ 2024-04-17 7:59 ` Heng Qi
2024-04-18 0:24 ` Jason Wang
2024-04-18 12:00 ` patchwork-bot+netdevbpf
3 siblings, 0 replies; 5+ messages in thread
From: Heng Qi @ 2024-04-17 7:59 UTC (permalink / raw)
To: Liang Chen
Cc: netdev, virtualization, linux-kernel, bpf, daniel, ast,
Michael S. Tsirkin, Jason Wang, Xuan Zhuo, David S . Miller,
Eric Dumazet, Jakub Kicinski, Paolo Abeni, Jesper Dangaard Brouer,
John Fastabend
在 2024/4/17 下午3:18, Liang Chen 写道:
> The RSS hash report is a feature that's part of the virtio specification.
> Currently, virtio backends like qemu, vdpa (mlx5), and potentially vhost
> (still a work in progress as per [1]) support this feature. While the
> capability to obtain the RSS hash has been enabled in the normal path,
> it's currently missing in the XDP path. Therefore, we are introducing
> XDP hints through kfuncs to allow XDP programs to access the RSS hash.
>
> 1.
> https://lore.kernel.org/all/20231015141644.260646-1-akihiko.odaki@daynix.com/#r
>
> Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Reviewed-by: Heng Qi <hengqi@linux.alibaba.com>
Thanks.
> ---
> Changes from v8:
> - move max table macro out of uAPI
> Changes from v7:
> - use table lookup for rss hash type
> Changes from v6:
> - fix a coding style issue
> Changes from v5:
> - Preservation of the hash value has been dropped, following the conclusion
> from discussions in V3 reviews. The virtio_net driver doesn't
> accessing/using the virtio_net_hdr after the XDP program execution, so
> nothing tragic should happen. As to the xdp program, if it smashes the
> entry in virtio header, it is likely buggy anyways. Additionally, looking
> up the Intel IGC driver, it also does not bother with this particular
> aspect.
> ---
> drivers/net/virtio_net.c | 43 ++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 43 insertions(+)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index c22d1118a133..eb99bf6c555e 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -4621,6 +4621,48 @@ static void virtnet_set_big_packets(struct virtnet_info *vi, const int mtu)
> }
> }
>
> +#define VIRTIO_NET_HASH_REPORT_MAX_TABLE 10
> +static enum xdp_rss_hash_type
> +virtnet_xdp_rss_type[VIRTIO_NET_HASH_REPORT_MAX_TABLE] = {
> + [VIRTIO_NET_HASH_REPORT_NONE] = XDP_RSS_TYPE_NONE,
> + [VIRTIO_NET_HASH_REPORT_IPv4] = XDP_RSS_TYPE_L3_IPV4,
> + [VIRTIO_NET_HASH_REPORT_TCPv4] = XDP_RSS_TYPE_L4_IPV4_TCP,
> + [VIRTIO_NET_HASH_REPORT_UDPv4] = XDP_RSS_TYPE_L4_IPV4_UDP,
> + [VIRTIO_NET_HASH_REPORT_IPv6] = XDP_RSS_TYPE_L3_IPV6,
> + [VIRTIO_NET_HASH_REPORT_TCPv6] = XDP_RSS_TYPE_L4_IPV6_TCP,
> + [VIRTIO_NET_HASH_REPORT_UDPv6] = XDP_RSS_TYPE_L4_IPV6_UDP,
> + [VIRTIO_NET_HASH_REPORT_IPv6_EX] = XDP_RSS_TYPE_L3_IPV6_EX,
> + [VIRTIO_NET_HASH_REPORT_TCPv6_EX] = XDP_RSS_TYPE_L4_IPV6_TCP_EX,
> + [VIRTIO_NET_HASH_REPORT_UDPv6_EX] = XDP_RSS_TYPE_L4_IPV6_UDP_EX
> +};
> +
> +static int virtnet_xdp_rx_hash(const struct xdp_md *_ctx, u32 *hash,
> + enum xdp_rss_hash_type *rss_type)
> +{
> + const struct xdp_buff *xdp = (void *)_ctx;
> + struct virtio_net_hdr_v1_hash *hdr_hash;
> + struct virtnet_info *vi;
> + u16 hash_report;
> +
> + if (!(xdp->rxq->dev->features & NETIF_F_RXHASH))
> + return -ENODATA;
> +
> + vi = netdev_priv(xdp->rxq->dev);
> + hdr_hash = (struct virtio_net_hdr_v1_hash *)(xdp->data - vi->hdr_len);
> + hash_report = __le16_to_cpu(hdr_hash->hash_report);
> +
> + if (hash_report >= VIRTIO_NET_HASH_REPORT_MAX_TABLE)
> + hash_report = VIRTIO_NET_HASH_REPORT_NONE;
> +
> + *rss_type = virtnet_xdp_rss_type[hash_report];
> + *hash = __le32_to_cpu(hdr_hash->hash_value);
> + return 0;
> +}
> +
> +static const struct xdp_metadata_ops virtnet_xdp_metadata_ops = {
> + .xmo_rx_hash = virtnet_xdp_rx_hash,
> +};
> +
> static int virtnet_probe(struct virtio_device *vdev)
> {
> int i, err = -ENOMEM;
> @@ -4747,6 +4789,7 @@ static int virtnet_probe(struct virtio_device *vdev)
> VIRTIO_NET_RSS_HASH_TYPE_UDP_EX);
>
> dev->hw_features |= NETIF_F_RXHASH;
> + dev->xdp_metadata_ops = &virtnet_xdp_metadata_ops;
> }
>
> if (vi->has_rss_hash_report)
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH net-next v9] virtio_net: Support RX hash XDP hint
2024-04-17 7:18 [PATCH net-next v9] virtio_net: Support RX hash XDP hint Liang Chen
2024-04-17 7:51 ` Jesper Dangaard Brouer
2024-04-17 7:59 ` Heng Qi
@ 2024-04-18 0:24 ` Jason Wang
2024-04-18 12:00 ` patchwork-bot+netdevbpf
3 siblings, 0 replies; 5+ messages in thread
From: Jason Wang @ 2024-04-18 0:24 UTC (permalink / raw)
To: Liang Chen
Cc: mst, xuanzhuo, hengqi, davem, edumazet, kuba, pabeni, hawk,
john.fastabend, netdev, virtualization, linux-kernel, bpf, daniel,
ast
On Wed, Apr 17, 2024 at 3:20 PM Liang Chen <liangchen.linux@gmail.com> wrote:
>
> The RSS hash report is a feature that's part of the virtio specification.
> Currently, virtio backends like qemu, vdpa (mlx5), and potentially vhost
> (still a work in progress as per [1]) support this feature. While the
> capability to obtain the RSS hash has been enabled in the normal path,
> it's currently missing in the XDP path. Therefore, we are introducing
> XDP hints through kfuncs to allow XDP programs to access the RSS hash.
>
> 1.
> https://lore.kernel.org/all/20231015141644.260646-1-akihiko.odaki@daynix.com/#r
>
> Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
> ---
Acked-by: Jason Wang <jasowang@redhat.com>
Thanks
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH net-next v9] virtio_net: Support RX hash XDP hint
2024-04-17 7:18 [PATCH net-next v9] virtio_net: Support RX hash XDP hint Liang Chen
` (2 preceding siblings ...)
2024-04-18 0:24 ` Jason Wang
@ 2024-04-18 12:00 ` patchwork-bot+netdevbpf
3 siblings, 0 replies; 5+ messages in thread
From: patchwork-bot+netdevbpf @ 2024-04-18 12:00 UTC (permalink / raw)
To: Liang Chen
Cc: mst, jasowang, xuanzhuo, hengqi, davem, edumazet, kuba, pabeni,
hawk, john.fastabend, netdev, virtualization, linux-kernel, bpf,
daniel, ast
Hello:
This patch was applied to netdev/net-next.git (main)
by Paolo Abeni <pabeni@redhat.com>:
On Wed, 17 Apr 2024 15:18:22 +0800 you wrote:
> The RSS hash report is a feature that's part of the virtio specification.
> Currently, virtio backends like qemu, vdpa (mlx5), and potentially vhost
> (still a work in progress as per [1]) support this feature. While the
> capability to obtain the RSS hash has been enabled in the normal path,
> it's currently missing in the XDP path. Therefore, we are introducing
> XDP hints through kfuncs to allow XDP programs to access the RSS hash.
>
> [...]
Here is the summary with links:
- [net-next,v9] virtio_net: Support RX hash XDP hint
https://git.kernel.org/netdev/net-next/c/aa37f8916d20
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
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^ permalink raw reply [flat|nested] 5+ messages in thread