diff mbox series

[v11,38/40] virtio_net: support rx queue resize

Message ID 20220629065656.54420-39-xuanzhuo@linux.alibaba.com (mailing list archive)
State Deferred, archived
Headers show
Series virtio pci support VIRTIO_F_RING_RESET | expand

Commit Message

Xuan Zhuo June 29, 2022, 6:56 a.m. UTC
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(+)

Comments

Jason Wang July 4, 2022, 3:44 a.m. UTC | #1
在 2022/6/29 14:56, 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 9fe222a3663a..6ab16fd193e5 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);


Do we need to cancel the refill work here?

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
Xuan Zhuo July 5, 2022, 1:59 a.m. UTC | #2
On Mon, 4 Jul 2022 11:44:12 +0800, Jason Wang <jasowang@redhat.com> wrote:
>
> 在 2022/6/29 14:56, 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 9fe222a3663a..6ab16fd193e5 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);
>
>
> Do we need to cancel the refill work here?


I think no, napi_disable is mutually exclusive, which ensures that there will be
no conflicts between them.

Thanks.

>
> 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
>
Jason Wang July 8, 2022, 6:20 a.m. UTC | #3
On Tue, Jul 5, 2022 at 10:00 AM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
>
> On Mon, 4 Jul 2022 11:44:12 +0800, Jason Wang <jasowang@redhat.com> wrote:
> >
> > 在 2022/6/29 14:56, 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 9fe222a3663a..6ab16fd193e5 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);
> >
> >
> > Do we need to cancel the refill work here?
>
>
> I think no, napi_disable is mutually exclusive, which ensures that there will be
> no conflicts between them.

So this sounds similar to what I've fixed recently.

1) NAPI schedule delayed work.
2) we disable NAPI here
3) delayed work get schedule and call NAPI again

?

Thanks

>
> Thanks.
>
> >
> > 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
> >
>
Xuan Zhuo July 15, 2022, 8:36 a.m. UTC | #4
On Fri, 8 Jul 2022 14:20:52 +0800, Jason Wang <jasowang@redhat.com> wrote:
> On Tue, Jul 5, 2022 at 10:00 AM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
> >
> > On Mon, 4 Jul 2022 11:44:12 +0800, Jason Wang <jasowang@redhat.com> wrote:
> > >
> > > 在 2022/6/29 14:56, 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 9fe222a3663a..6ab16fd193e5 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);
> > >
> > >
> > > Do we need to cancel the refill work here?
> >
> >
> > I think no, napi_disable is mutually exclusive, which ensures that there will be
> > no conflicts between them.
>
> So this sounds similar to what I've fixed recently.
>
> 1) NAPI schedule delayed work.
> 2) we disable NAPI here
> 3) delayed work get schedule and call NAPI again
>
> ?

Yes, but I don't think there are any negative effects.

Thanks.

>
> Thanks
>
> >
> > Thanks.
> >
> > >
> > > 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
> > >
> >
>
Jason Wang July 18, 2022, 8:56 a.m. UTC | #5
On Fri, Jul 15, 2022 at 4:37 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
>
> On Fri, 8 Jul 2022 14:20:52 +0800, Jason Wang <jasowang@redhat.com> wrote:
> > On Tue, Jul 5, 2022 at 10:00 AM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
> > >
> > > On Mon, 4 Jul 2022 11:44:12 +0800, Jason Wang <jasowang@redhat.com> wrote:
> > > >
> > > > 在 2022/6/29 14:56, 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 9fe222a3663a..6ab16fd193e5 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);
> > > >
> > > >
> > > > Do we need to cancel the refill work here?
> > >
> > >
> > > I think no, napi_disable is mutually exclusive, which ensures that there will be
> > > no conflicts between them.
> >
> > So this sounds similar to what I've fixed recently.
> >
> > 1) NAPI schedule delayed work.
> > 2) we disable NAPI here
> > 3) delayed work get schedule and call NAPI again
> >
> > ?
>
> Yes, but I don't think there are any negative effects.

An infinite wait on the napi_disable()?

Thanks

>
> Thanks.
>
> >
> > Thanks
> >
> > >
> > > Thanks.
> > >
> > > >
> > > > 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
> > > >
> > >
> >
>
Xuan Zhuo July 18, 2022, 8:58 a.m. UTC | #6
On Mon, 18 Jul 2022 16:56:24 +0800, Jason Wang <jasowang@redhat.com> wrote:
> On Fri, Jul 15, 2022 at 4:37 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
> >
> > On Fri, 8 Jul 2022 14:20:52 +0800, Jason Wang <jasowang@redhat.com> wrote:
> > > On Tue, Jul 5, 2022 at 10:00 AM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
> > > >
> > > > On Mon, 4 Jul 2022 11:44:12 +0800, Jason Wang <jasowang@redhat.com> wrote:
> > > > >
> > > > > 在 2022/6/29 14:56, 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 9fe222a3663a..6ab16fd193e5 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);
> > > > >
> > > > >
> > > > > Do we need to cancel the refill work here?
> > > >
> > > >
> > > > I think no, napi_disable is mutually exclusive, which ensures that there will be
> > > > no conflicts between them.
> > >
> > > So this sounds similar to what I've fixed recently.
> > >
> > > 1) NAPI schedule delayed work.
> > > 2) we disable NAPI here
> > > 3) delayed work get schedule and call NAPI again
> > >
> > > ?
> >
> > Yes, but I don't think there are any negative effects.
>
> An infinite wait on the napi_disable()?

Yes.

Thanks.


>
> Thanks
>
> >
> > Thanks.
> >
> > >
> > > Thanks
> > >
> > > >
> > > > Thanks.
> > > >
> > > > >
> > > > > 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
> > > > >
> > > >
> > >
> >
>
diff mbox series

Patch

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 9fe222a3663a..6ab16fd193e5 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);
+
+	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