Both 'indirect_desc' and 'event_idx' are bus independent features,
and they should be enabled for mmio devices too.
On arm64 quad core VM(qemu-kvm), the patch can increase block I/O
performance a lot with latest linux tree:
- without the patch: 14K IOPS
- with the patch: 34K IOPS
fio script:
[global]
direct=1
bsrange=4k-4k
timeout=10
numjobs=4
ioengine=libaio
iodepth=64
filename=/dev/vdc
group_reporting=1
[f1]
rw=randread
Cc: Peter Maydell <peter.mayd...@linaro.org>
Signed-off-by: Ming Lei <ming....@canonical.com>
---
hw/virtio/virtio-mmio.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/hw/virtio/virtio-mmio.c b/hw/virtio/virtio-mmio.c
index 8829eb0..18c6e5b 100644
--- a/hw/virtio/virtio-mmio.c
+++ b/hw/virtio/virtio-mmio.c
@@ -369,10 +369,16 @@ static void virtio_mmio_realizefn(DeviceState *d, Error
**errp)
sysbus_init_mmio(sbd, &proxy->iomem);
}
+static Property virtio_mmio_properties[] = {
+ DEFINE_VIRTIO_COMMON_FEATURES(VirtIOMMIOProxy, host_features),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
static void virtio_mmio_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
+ dc->props = virtio_mmio_properties;
dc->realize = virtio_mmio_realizefn;
dc->reset = virtio_mmio_reset;
set_bit(DEVICE_CATEGORY_MISC, dc->categories);
--
1.7.9.5
