| Message ID | 20221014160947.66105-1-philmd@fungible.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | virtio-rng-pci: Allow setting nvectors, so we can use MSI-X | expand |
On Fri, 14 Oct 2022 at 12:10, Philippe Mathieu-Daudé <philmd@fungible.com> wrote: > > From: David Daney <david.daney@fungible.com> > > Most other virtio-pci devices allow MSI-X, let's have it for rng too. > > Signed-off-by: David Daney <david.daney@fungible.com> > Reviewed-by: Marcin Nowakowski <marcin.nowakowski@fungible.com> > Signed-off-by: Philippe Mathieu-Daudé <philmd@fungible.com> > --- > hw/virtio/virtio-rng-pci.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/hw/virtio/virtio-rng-pci.c b/hw/virtio/virtio-rng-pci.c > index 151ece6f94..6e76f8b57b 100644 > --- a/hw/virtio/virtio-rng-pci.c > +++ b/hw/virtio/virtio-rng-pci.c > @@ -13,6 +13,7 @@ > > #include "hw/virtio/virtio-pci.h" > #include "hw/virtio/virtio-rng.h" > +#include "hw/qdev-properties.h" > #include "qapi/error.h" > #include "qemu/module.h" > #include "qom/object.h" > @@ -31,11 +32,23 @@ struct VirtIORngPCI { > VirtIORNG vdev; > }; > > +static Property virtio_rng_properties[] = { > + DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags, > + VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true), ioeventfd is unrelated to MSI-X. It controls whether the virtqueue kick is handled in the vCPU thread (ioctl(KVM_RUN) exit) or the main loop thread (KVM ioeventfd). I took a quick look at virtio-rng.c to see if there is anything that doesn't work in the main loop. It looks okay to me but consider dropping this line to minimize the risk of breaking something. > + DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, > + DEV_NVECTORS_UNSPECIFIED), > + DEFINE_PROP_END_OF_LIST(), > +}; > + > static void virtio_rng_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp) > { > VirtIORngPCI *vrng = VIRTIO_RNG_PCI(vpci_dev); > DeviceState *vdev = DEVICE(&vrng->vdev); > > + if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) { > + vpci_dev->nvectors = 2; Checked against the spec: 1 configuration change notification and 1 virtqueue used buffer notification = 2 MSI-X vectors. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> > + } > + > if (!qdev_realize(vdev, BUS(&vpci_dev->bus), errp)) { > return; > } > @@ -54,6 +67,7 @@ static void virtio_rng_pci_class_init(ObjectClass *klass, void *data) > pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_RNG; > pcidev_k->revision = VIRTIO_PCI_ABI_VERSION; > pcidev_k->class_id = PCI_CLASS_OTHERS; > + device_class_set_props(dc, virtio_rng_properties); > } > > static void virtio_rng_initfn(Object *obj) > -- > 2.37.3 > >
diff --git a/hw/virtio/virtio-rng-pci.c b/hw/virtio/virtio-rng-pci.c index 151ece6f94..6e76f8b57b 100644 --- a/hw/virtio/virtio-rng-pci.c +++ b/hw/virtio/virtio-rng-pci.c @@ -13,6 +13,7 @@ #include "hw/virtio/virtio-pci.h" #include "hw/virtio/virtio-rng.h" +#include "hw/qdev-properties.h" #include "qapi/error.h" #include "qemu/module.h" #include "qom/object.h" @@ -31,11 +32,23 @@ struct VirtIORngPCI { VirtIORNG vdev; }; +static Property virtio_rng_properties[] = { + DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags, + VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true), + DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, + DEV_NVECTORS_UNSPECIFIED), + DEFINE_PROP_END_OF_LIST(), +}; + static void virtio_rng_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp) { VirtIORngPCI *vrng = VIRTIO_RNG_PCI(vpci_dev); DeviceState *vdev = DEVICE(&vrng->vdev); + if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) { + vpci_dev->nvectors = 2; + } + if (!qdev_realize(vdev, BUS(&vpci_dev->bus), errp)) { return; } @@ -54,6 +67,7 @@ static void virtio_rng_pci_class_init(ObjectClass *klass, void *data) pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_RNG; pcidev_k->revision = VIRTIO_PCI_ABI_VERSION; pcidev_k->class_id = PCI_CLASS_OTHERS; + device_class_set_props(dc, virtio_rng_properties); } static void virtio_rng_initfn(Object *obj)