Re: [PATCH v12 38/40] virtio_net: support rx queue resize

Jason Wang
2022-07-21T09:26:25Z

在 2022/7/20 11:04, Xuan Zhuo 写道:
> This patch implements the resize function of the rx queues.
> Based on this function, it is possible to modify the ring num of the
> queue.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> ---
> drivers/net/virtio_net.c | 22 ++++++++++++++++++++++
> 1 file changed, 22 insertions(+)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index fe4dc43c05a1..1115a8b59a08 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -278,6 +278,8 @@ struct padded_vnet_hdr {
> char padding[12];
> };
>
> +static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf);
> +
> static bool is_xdp_frame(void *ptr)
> {
> return (unsigned long)ptr & VIRTIO_XDP_FLAG;
> @@ -1846,6 +1848,26 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
> return NETDEV_TX_OK;
> }
>
> +static int virtnet_rx_resize(struct virtnet_info *vi,
> + struct receive_queue *rq, u32 ring_num)
> +{
> + int err, qindex;
> +
> + qindex = rq - vi->rq;
> +
> + napi_disable(&rq->napi);

We need to disable refill work as well. So this series might need
rebasing on top of

https://lore.kernel.org/netdev/20220704074859.16912-1-jasowang@redhat.com/

I will send a new version (probably tomorrow).

Thanks

> +
> + err = virtqueue_resize(rq->vq, ring_num, virtnet_rq_free_unused_buf);
> + if (err)
> + netdev_err(vi->dev, "resize rx fail: rx queue index: %d err: %d\n", qindex, err);
> +
> + if (!try_fill_recv(vi, rq, GFP_KERNEL))
> + schedule_delayed_work(&vi->refill, 0);
> +
> + virtnet_napi_enable(rq->vq, &rq->napi);
> + return err;
> +}
> +
> /*
> * Send command via the control virtqueue and check status. Commands
> * supported by the hypervisor, as indicated by feature bits, should