Now that there is not anymore a switch from the generic ioeventfd handler to the dataplane handler, virtio_bus_set_host_notifier(assign=true) is always called with !bus->ioeventfd_started, hence virtio_bus_stop_ioeventfd does nothing in this case. Move the invocation to vhost.c, which is the only place that needs it.
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> --- hw/virtio/vhost.c | 3 +++ hw/virtio/virtio-bus.c | 23 ++++++++--------------- include/hw/virtio/virtio-bus.h | 6 ------ 3 files changed, 11 insertions(+), 21 deletions(-) diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index c5a1fe0..284bee1 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -1182,6 +1182,7 @@ int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) goto fail; } + virtio_device_stop_ioeventfd(vdev); for (i = 0; i < hdev->nvqs; ++i) { r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, true); @@ -1201,6 +1202,7 @@ fail_vq: } assert (e >= 0); } + virtio_device_start_ioeventfd(vdev); fail: return r; } @@ -1223,6 +1225,7 @@ void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) } assert (r >= 0); } + virtio_device_start_ioeventfd(vdev); } /* Test and clear event pending status. diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c index c196ba1..ef8f622 100644 --- a/hw/virtio/virtio-bus.c +++ b/hw/virtio/virtio-bus.c @@ -188,7 +188,7 @@ int virtio_bus_start_ioeventfd(VirtioBusState *bus) if (!k->ioeventfd_assign || !k->ioeventfd_enabled(proxy)) { return -ENOSYS; } - if (bus->ioeventfd_started || bus->ioeventfd_disabled) { + if (bus->ioeventfd_started) { return 0; } r = vdc->start_ioeventfd(vdev); @@ -221,8 +221,8 @@ bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus) } /* - * This function switches from/to the generic ioeventfd handler. - * assign==false means 'use generic ioeventfd handler'. + * This function switches ioeventfd on/off in the device. + * The caller must set or clear the handlers for the EventNotifier. */ int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign) { @@ -232,19 +232,12 @@ int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign) if (!k->ioeventfd_assign) { return -ENOSYS; } - bus->ioeventfd_disabled = assign; if (assign) { - /* - * Stop using the generic ioeventfd, we are doing eventfd handling - * ourselves below - * - * FIXME: We should just switch the handler and not deassign the - * ioeventfd. - * Otherwise, there's a window where we don't have an - * ioeventfd and we may end up with a notification where - * we don't expect one. - */ - virtio_bus_stop_ioeventfd(bus); + assert(!bus->ioeventfd_started); + } else { + if (!bus->ioeventfd_started) { + return 0; + } } return set_host_notifier_internal(proxy, bus, n, assign); } diff --git a/include/hw/virtio/virtio-bus.h b/include/hw/virtio/virtio-bus.h index 0abc890..b812cad 100644 --- a/include/hw/virtio/virtio-bus.h +++ b/include/hw/virtio/virtio-bus.h @@ -94,12 +94,6 @@ struct VirtioBusState { BusState parent_obj; /* - * Set if the default ioeventfd handlers are disabled by vhost - * or dataplane. - */ - bool ioeventfd_disabled; - - /* * Set if ioeventfd has been started. */ bool ioeventfd_started; -- 2.7.4