diff mbox series

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

Message ID 20220720030436.79520-39-xuanzhuo@linux.alibaba.com (mailing list archive)
State Superseded
Headers show
Series virtio pci support VIRTIO_F_RING_RESET | expand

Commit Message

Xuan Zhuo July 20, 2022, 3:04 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 21, 2022, 9:25 a.m. UTC | #1
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
Xuan Zhuo July 25, 2022, 6:38 a.m. UTC | #2
On Thu, 21 Jul 2022 17:25:59 +0800, Jason Wang <jasowang@redhat.com> wrote:
>
> 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 understand that your patch is used to solve the situation where dev is
destoryed but refill work is running.

And is there such a possibility here? Or is there any other scenario that I'm
not expecting?

Thanks.


>
> 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
>
Jason Wang July 25, 2022, 6:57 a.m. UTC | #3
On Mon, Jul 25, 2022 at 2:43 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
>
> On Thu, 21 Jul 2022 17:25:59 +0800, Jason Wang <jasowang@redhat.com> wrote:
> >
> > 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 understand that your patch is used to solve the situation where dev is
> destoryed but refill work is running.
>
> And is there such a possibility here?

E.g the refill work runs in parallel with this function?

Thanks

> Or is there any other scenario that I'm
> not expecting?
>
> Thanks.
>
>
> >
> > 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
> >
>
Xuan Zhuo July 25, 2022, 7:21 a.m. UTC | #4
On Mon, 25 Jul 2022 14:57:11 +0800, Jason Wang <jasowang@redhat.com> wrote:
> On Mon, Jul 25, 2022 at 2:43 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
> >
> > On Thu, 21 Jul 2022 17:25:59 +0800, Jason Wang <jasowang@redhat.com> wrote:
> > >
> > > 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 understand that your patch is used to solve the situation where dev is
> > destoryed but refill work is running.
> >
> > And is there such a possibility here?
>
> E.g the refill work runs in parallel with this function?

napi_disable enables lock-like functionality. So I think it's safe.

Thanks.

>
> Thanks
>
> > Or is there any other scenario that I'm
> > not expecting?
> >
> > Thanks.
> >
> >
> > >
> > > 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
> > >
> >
>
Jason Wang July 25, 2022, 7:28 a.m. UTC | #5
On Mon, Jul 25, 2022 at 3:23 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
>
> On Mon, 25 Jul 2022 14:57:11 +0800, Jason Wang <jasowang@redhat.com> wrote:
> > On Mon, Jul 25, 2022 at 2:43 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
> > >
> > > On Thu, 21 Jul 2022 17:25:59 +0800, Jason Wang <jasowang@redhat.com> wrote:
> > > >
> > > > 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 understand that your patch is used to solve the situation where dev is
> > > destoryed but refill work is running.
> > >
> > > And is there such a possibility here?
> >
> > E.g the refill work runs in parallel with this function?
>
> napi_disable enables lock-like functionality. So I think it's safe.
>

Ok, right, since there will be a napi_enable() soon afterwards.

So

Acked-by: Jason Wang <jasowang@redhat.com>

Thanks

> Thanks.
>
> >
> > Thanks
> >
> > > Or is there any other scenario that I'm
> > > not expecting?
> > >
> > > Thanks.
> > >
> > >
> > > >
> > > > 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
> > > >
> > >
> >
>
diff mbox series

Patch

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);
+
+	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