Re: [Qemu-devel] [PATCH] hw/virtio: enable common virtio feature for mmio device

[Paolo Bonzini <pbonzini@redhat.com>]

Il 09/06/2014 10:00, Ming Lei ha scritto:
> On Wed, Jun 4, 2014 at 10:05 AM, Ming Lei <ming.lei@canonical.com> wrote:
>> 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.maydell@linaro.org>
>> Signed-off-by: Ming Lei <ming.lei@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

Looks good.  Can you look into moving DEFINE_VIRTIO_COMMON_FEATURES from 
all virtio pci devices to TYPE_VIRTIO_PCI, too?

Thanks,

Paolo