Re: [PATCH net-next v3] virtio-net: xsk: support tx wake up

[Menglong Dong]

On 2026/6/22 06:06 Jakub Kicinski <kuba@xxxxxxxxxx> write:
> On Tue, 16 Jun 2026 19:59:12 +0800 Menglong Dong wrote:
> > For now, XDP_RING_NEED_WAKEUP is not supported properly by the virtio-net
> > in the tx path for example: we set xsk_set_tx_need_wakeup() in
> > virtnet_xsk_xmit(), but we didn't call xsk_clear_tx_need_wakeup()
> > anywhere, which means the user will call send() for every packet.
> > 
> > We call xsk_set_tx_need_wakeup() after virtnet_xsk_xmit_batch() if sq->vq
> > is empty, as we can't be wakeup by the skb_xmit_done() in this case.
> > Otherwise, we will clear the wakeup flag.
> > 
> > Race condition is considered for tx path.
> 
> Seems to follow what mlx5 does so presumably this is fine but IDK if

Yeah, I followed the logic of mlx5. It's amazing that you found it :)

> there's anything virtio-specific that we need to be worried about.
> 
> Xuan Zhuo, please TAL?
> -- 
> mping: VIRTIO NET DRIVER
> 
>