On Thu, Jan 16, 2025 at 3:57 PM Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> wrote:
>
> On Thu, 16 Jan 2025 05:52:58 +0000, Joe Damato <jdamato@xxxxxxxxxx> wrote:
> > Use netif_queue_set_napi to map NAPIs to queue IDs so that the mapping
> > can be accessed by user apps.
> >
> > $ ethtool -i ens4 | grep driver
> > driver: virtio_net
> >
> > $ sudo ethtool -L ens4 combined 4
> >
> > $ ./tools/net/ynl/pyynl/cli.py \
> > --spec Documentation/netlink/specs/netdev.yaml \
> > --dump queue-get --json='{"ifindex": 2}'
> > [{'id': 0, 'ifindex': 2, 'napi-id': 8289, 'type': 'rx'},
> > {'id': 1, 'ifindex': 2, 'napi-id': 8290, 'type': 'rx'},
> > {'id': 2, 'ifindex': 2, 'napi-id': 8291, 'type': 'rx'},
> > {'id': 3, 'ifindex': 2, 'napi-id': 8292, 'type': 'rx'},
> > {'id': 0, 'ifindex': 2, 'type': 'tx'},
> > {'id': 1, 'ifindex': 2, 'type': 'tx'},
> > {'id': 2, 'ifindex': 2, 'type': 'tx'},
> > {'id': 3, 'ifindex': 2, 'type': 'tx'}]
> >
> > Note that virtio_net has TX-only NAPIs which do not have NAPI IDs, so
> > the lack of 'napi-id' in the above output is expected.
> >
> > Signed-off-by: Joe Damato <jdamato@xxxxxxxxxx>
> > ---
> > v2:
> > - Eliminate RTNL code paths using the API Jakub introduced in patch 1
> > of this v2.
> > - Added virtnet_napi_disable to reduce code duplication as
> > suggested by Jason Wang.
> >
> > drivers/net/virtio_net.c | 34 +++++++++++++++++++++++++++++-----
> > 1 file changed, 29 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > index cff18c66b54a..c6fda756dd07 100644
> > --- a/drivers/net/virtio_net.c
> > +++ b/drivers/net/virtio_net.c
> > @@ -2803,9 +2803,18 @@ static void virtnet_napi_do_enable(struct virtqueue *vq,
> > local_bh_enable();
> > }
> >
> > -static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
> > +static void virtnet_napi_enable(struct virtqueue *vq,
> > + struct napi_struct *napi)
> > {
> > + struct virtnet_info *vi = vq->vdev->priv;
> > + int q = vq2rxq(vq);
> > + u16 curr_qs;
> > +
> > virtnet_napi_do_enable(vq, napi);
> > +
> > + curr_qs = vi->curr_queue_pairs - vi->xdp_queue_pairs;
> > + if (!vi->xdp_enabled || q < curr_qs)
> > + netif_queue_set_napi(vi->dev, q, NETDEV_QUEUE_TYPE_RX, napi);
>
> So what case the check of xdp_enabled is for?
+1 and I think the XDP related checks should be done by the caller not here.
>
> And I think we should merge this to last commit.
>
> Thanks.
>
Thanks
> > }
> >
> > static void virtnet_napi_tx_enable(struct virtnet_info *vi,
> > @@ -2826,6 +2835,20 @@ static void virtnet_napi_tx_enable(struct virtnet_info *vi,
> > virtnet_napi_do_enable(vq, napi);
> > }
> >
> > +static void virtnet_napi_disable(struct virtqueue *vq,
> > + struct napi_struct *napi)
> > +{
> > + struct virtnet_info *vi = vq->vdev->priv;
> > + int q = vq2rxq(vq);
> > + u16 curr_qs;
> > +
> > + curr_qs = vi->curr_queue_pairs - vi->xdp_queue_pairs;
> > + if (!vi->xdp_enabled || q < curr_qs)
> > + netif_queue_set_napi(vi->dev, q, NETDEV_QUEUE_TYPE_RX, NULL);
> > +
> > + napi_disable(napi);
> > +}
> > +
> > static void virtnet_napi_tx_disable(struct napi_struct *napi)
> > {
> > if (napi->weight)
> > @@ -2842,7 +2865,8 @@ static void refill_work(struct work_struct *work)
> > for (i = 0; i < vi->curr_queue_pairs; i++) {
> > struct receive_queue *rq = &vi->rq[i];
> >
> > - napi_disable(&rq->napi);
> > + virtnet_napi_disable(rq->vq, &rq->napi);
> > +
> > still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
> > virtnet_napi_enable(rq->vq, &rq->napi);
> >
> > @@ -3042,7 +3066,7 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
> > static void virtnet_disable_queue_pair(struct virtnet_info *vi, int qp_index)
> > {
> > virtnet_napi_tx_disable(&vi->sq[qp_index].napi);
> > - napi_disable(&vi->rq[qp_index].napi);
> > + virtnet_napi_disable(vi->rq[qp_index].vq, &vi->rq[qp_index].napi);
> > xdp_rxq_info_unreg(&vi->rq[qp_index].xdp_rxq);
> > }
> >
> > @@ -3313,7 +3337,7 @@ static void virtnet_rx_pause(struct virtnet_info *vi, struct receive_queue *rq)
> > bool running = netif_running(vi->dev);
> >
> > if (running) {
> > - napi_disable(&rq->napi);
> > + virtnet_napi_disable(rq->vq, &rq->napi);
> > virtnet_cancel_dim(vi, &rq->dim);
> > }
> > }
> > @@ -5932,7 +5956,7 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
> > /* Make sure NAPI is not using any XDP TX queues for RX. */
> > if (netif_running(dev)) {
> > for (i = 0; i < vi->max_queue_pairs; i++) {
> > - napi_disable(&vi->rq[i].napi);
> > + virtnet_napi_disable(vi->rq[i].vq, &vi->rq[i].napi);
> > virtnet_napi_tx_disable(&vi->sq[i].napi);
> > }
> > }
> > --
> > 2.25.1
> >
>
