Re: [PATCH v6 7/9] virtio-pci: add support for configure interrupt

[Cindy Lu]

On Tue, Apr 27, 2021 at 3:12 PM Jason Wang <jasowang@redhat.com> wrote:
>
>
> 在 2021/4/27 上午11:39, Cindy Lu 写道:
> > Add support for configure interrupt, use kvm_irqfd_assign and set the
> > gsi to kernel. When the configure notifier was eventfd_signal by host
> > kernel, this will finally inject an msix interrupt to guest
> > ---
> >   hw/virtio/virtio-pci.c | 186 ++++++++++++++++++++++++++---------------
> >   1 file changed, 120 insertions(+), 66 deletions(-)
> >
> > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> > index 2b7e6cc0d9..07d28dd367 100644
> > --- a/hw/virtio/virtio-pci.c
> > +++ b/hw/virtio/virtio-pci.c
> > @@ -664,12 +664,10 @@ static uint32_t virtio_read_config(PCIDevice *pci_dev,
> >   }
> >
> >   static int kvm_virtio_pci_vq_vector_use(VirtIOPCIProxy *proxy,
> > -                                        unsigned int queue_no,
> >                                           unsigned int vector)
> >   {
> >       VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
> >       int ret;
> > -
>
>
> Unnecessary changes.
>
will fix this
>
> >       if (irqfd->users == 0) {
> >           ret = kvm_irqchip_add_msi_route(kvm_state, vector, 
> > &proxy->pci_dev);
> >           if (ret < 0) {
> > @@ -708,93 +706,120 @@ static void 
> > kvm_virtio_pci_irqfd_release(VirtIOPCIProxy *proxy,
> >       ret = kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, n, 
> > irqfd->virq);
> >       assert(ret == 0);
> >   }
> > -
>
>
> So did here.
>
will fix this
>
> > -static int kvm_virtio_pci_vector_use(VirtIOPCIProxy *proxy, int nvqs)
> > + static int virtio_pci_get_notifier(VirtIOPCIProxy *proxy, int queue_no,
> > +                                      EventNotifier **n, unsigned int 
> > *vector)
>
>
> The indentation looks not correct.
>
>
> >   {
> >       PCIDevice *dev = &proxy->pci_dev;
> >       VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
> > -    VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
> > -    unsigned int vector;
> > -    int ret, queue_no;
> >       VirtQueue *vq;
> > -    EventNotifier *n;
> > -    for (queue_no = 0; queue_no < nvqs; queue_no++) {
> > +
> > +    if (queue_no == -1) {
> > +        *n = virtio_get_config_notifier(vdev);
> > +        *vector = vdev->config_vector;
> > +    } else {
> >           if (!virtio_queue_get_num(vdev, queue_no)) {
> > -            break;
> > -        }
> > -        vector = virtio_queue_vector(vdev, queue_no);
> > -        if (vector >= msix_nr_vectors_allocated(dev)) {
> > -            continue;
> > -        }
> > -        ret = kvm_virtio_pci_vq_vector_use(proxy, queue_no, vector);
> > -        if (ret < 0) {
> > -            goto undo;
> > -        }
> > -        /* If guest supports masking, set up irqfd now.
> > -         * Otherwise, delay until unmasked in the frontend.
> > -         */
> > -        if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
> > -            vq = virtio_get_queue(vdev, queue_no);
> > -            n = virtio_queue_get_guest_notifier(vq);
> > -            ret = kvm_virtio_pci_irqfd_use(proxy, n, vector);
> > -            if (ret < 0) {
> > -                kvm_virtio_pci_vq_vector_release(proxy, vector);
> > -                goto undo;
> > -            }
> > +            return -1;
> >           }
> > +        *vector = virtio_queue_vector(vdev, queue_no);
> > +        vq = virtio_get_queue(vdev, queue_no);
> > +        *n = virtio_queue_get_guest_notifier(vq);
> > +    }
> > +    if (*vector >= msix_nr_vectors_allocated(dev)) {
> > +        return -1;
> >       }
> >       return 0;
> > +}
> >
> > +static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int 
> > queue_no)
> > +{
>
>
> Let's use separate patch for the introducing of
> kvm_virtio_pci_vector_user/release_one().
>
> And then do the config interrupt support on top.
>
Sure, will fix this
> Thanks
>