summaryrefslogtreecommitdiff
path: root/hw/virtio-pci.c
diff options
context:
space:
mode:
authorMichael S. Tsirkin <mst@redhat.com>2012-12-20 14:28:58 +0200
committerMichael S. Tsirkin <mst@redhat.com>2013-01-07 19:42:22 +0200
commit2d620f593d9395abd9aa453f8ae0861a51d674d8 (patch)
treed3cab64b07a957ce4334b1a3ad5f1ba1a08c95d4 /hw/virtio-pci.c
parent8e4a424b305e29dc0e454f52df3b35577f342975 (diff)
downloadqemu-2d620f593d9395abd9aa453f8ae0861a51d674d8.tar.gz
virtio: don't waste irqfds on control vqs
Pass nvqs to set_guest_notifiers. This makes it possible to save on irqfds by not allocating one for the control vq for virtio-net. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'hw/virtio-pci.c')
-rw-r--r--hw/virtio-pci.c19
1 files changed, 14 insertions, 5 deletions
diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index c7f0c4d4ed..65a563bdb2 100644
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -535,7 +535,7 @@ static int kvm_virtio_pci_vector_use(PCIDevice *dev, unsigned vector,
VirtIODevice *vdev = proxy->vdev;
int ret, queue_no;
- for (queue_no = 0; queue_no < VIRTIO_PCI_QUEUE_MAX; queue_no++) {
+ for (queue_no = 0; queue_no < proxy->nvqs_with_notifiers; queue_no++) {
if (!virtio_queue_get_num(vdev, queue_no)) {
break;
}
@@ -565,7 +565,7 @@ static void kvm_virtio_pci_vector_release(PCIDevice *dev, unsigned vector)
VirtIODevice *vdev = proxy->vdev;
int queue_no;
- for (queue_no = 0; queue_no < VIRTIO_PCI_QUEUE_MAX; queue_no++) {
+ for (queue_no = 0; queue_no < proxy->nvqs_with_notifiers; queue_no++) {
if (!virtio_queue_get_num(vdev, queue_no)) {
break;
}
@@ -587,7 +587,7 @@ static void kvm_virtio_pci_vector_poll(PCIDevice *dev,
EventNotifier *notifier;
VirtQueue *vq;
- for (queue_no = 0; queue_no < VIRTIO_PCI_QUEUE_MAX; queue_no++) {
+ for (queue_no = 0; queue_no < proxy->nvqs_with_notifiers; queue_no++) {
if (!virtio_queue_get_num(vdev, queue_no)) {
break;
}
@@ -631,7 +631,7 @@ static bool virtio_pci_query_guest_notifiers(DeviceState *d)
return msix_enabled(&proxy->pci_dev);
}
-static int virtio_pci_set_guest_notifiers(DeviceState *d, bool assign)
+static int virtio_pci_set_guest_notifiers(DeviceState *d, int nvqs, bool assign)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
VirtIODevice *vdev = proxy->vdev;
@@ -639,6 +639,15 @@ static int virtio_pci_set_guest_notifiers(DeviceState *d, bool assign)
bool with_irqfd = msix_enabled(&proxy->pci_dev) &&
kvm_msi_via_irqfd_enabled();
+ nvqs = MIN(nvqs, VIRTIO_PCI_QUEUE_MAX);
+
+ /* When deassigning, pass a consistent nvqs value
+ * to avoid leaking notifiers.
+ */
+ assert(assign || nvqs == proxy->nvqs_with_notifiers);
+
+ proxy->nvqs_with_notifiers = nvqs;
+
/* Must unset vector notifier while guest notifier is still assigned */
if (proxy->vector_irqfd && !assign) {
msix_unset_vector_notifiers(&proxy->pci_dev);
@@ -646,7 +655,7 @@ static int virtio_pci_set_guest_notifiers(DeviceState *d, bool assign)
proxy->vector_irqfd = NULL;
}
- for (n = 0; n < VIRTIO_PCI_QUEUE_MAX; n++) {
+ for (n = 0; n < nvqs; n++) {
if (!virtio_queue_get_num(vdev, n)) {
break;
}