diff options
Diffstat (limited to 'hw/virtio/virtio.c')
| -rw-r--r-- | hw/virtio/virtio.c | 28 |
1 files changed, 13 insertions, 15 deletions
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 34f977a3c9..6ce5823898 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -31,6 +31,7 @@ #include "hw/qdev-properties.h" #include "hw/virtio/virtio-access.h" #include "system/dma.h" +#include "system/iothread.h" #include "system/runstate.h" #include "virtio-qmp.h" @@ -2654,16 +2655,8 @@ static void virtio_notify_irqfd_deferred_fn(void *opaque) event_notifier_set(notifier); } -void virtio_notify_irqfd(VirtIODevice *vdev, VirtQueue *vq) +static void virtio_irq(VirtQueue *vq) { - WITH_RCU_READ_LOCK_GUARD() { - if (!virtio_should_notify(vdev, vq)) { - return; - } - } - - trace_virtio_notify_irqfd(vdev, vq); - /* * virtio spec 1.0 says ISR bit 0 should be ignored with MSI, but * windows drivers included in virtio-win 1.8.0 (circa 2015) are @@ -2680,13 +2673,18 @@ void virtio_notify_irqfd(VirtIODevice *vdev, VirtQueue *vq) * to an atomic operation. */ virtio_set_isr(vq->vdev, 0x1); - defer_call(virtio_notify_irqfd_deferred_fn, &vq->guest_notifier); -} -static void virtio_irq(VirtQueue *vq) -{ - virtio_set_isr(vq->vdev, 0x1); - virtio_notify_vector(vq->vdev, vq->vector); + /* + * The interrupt code path requires the Big QEMU Lock (BQL), so use the + * notifier instead when in an IOThread. This assumes that device models + * have already called ->set_guest_notifiers() sometime before calling this + * function. + */ + if (qemu_in_iothread()) { + defer_call(virtio_notify_irqfd_deferred_fn, &vq->guest_notifier); + } else { + virtio_notify_vector(vq->vdev, vq->vector); + } } void virtio_notify(VirtIODevice *vdev, VirtQueue *vq) |