On Tue, Jan 12, 2010 at 04:39:52PM -0600, Anthony Liguori wrote:
> On 01/11/2010 11:22 AM, Michael S. Tsirkin wrote:
>> Looks like order got mixed up: vhost_net header
>> is added by a follow-up patch. Will be fixed
>> in the next revision.
>>
>> Signed-off-by: Michael S. Tsirkin<m...@redhat.com>
>> ---
>> net.c | 8 ++++++++
>> net/tap.c | 29 +++++++++++++++++++++++++++++
>> qemu-options.hx | 4 +++-
>> 3 files changed, 40 insertions(+), 1 deletions(-)
>>
>> diff --git a/net.c b/net.c
>> index 6ef93e6..b942d03 100644
>> --- a/net.c
>> +++ b/net.c
>> @@ -976,6 +976,14 @@ static struct {
>> .name = "vnet_hdr",
>> .type = QEMU_OPT_BOOL,
>> .help = "enable the IFF_VNET_HDR flag on the tap interface"
>> + }, {
>> + .name = "vhost",
>> + .type = QEMU_OPT_BOOL,
>> + .help = "enable vhost-net network accelerator",
>> + }, {
>> + .name = "vhostfd",
>> + .type = QEMU_OPT_STRING,
>> + .help = "file descriptor of an already opened vhost net
>> device",
>> },
>>
>
> Semantically, I think making vhost it's own backend makes more sense
> from a user perspective.
It doesn't. Users mostly do not care that vhost is used: they just get
fast virtio and that's all. Users do care about e.g. tap because they
need setup scripts, understand bridging etc.
Do you propose -net tap be replaced with -net vhost? This means vhost will
need to get tap flags if it is attached to tap and raw flags if attached
to raw, etc.
A separate backend that only works with virtio frontend is also
ugly. OTOH an option that has effect only with virtio frontend
is pretty usual, vnet_hdr is one such example.
>
> I don't think it's a significant code change.
>
> Regards,
>
> Anthony Liguori
--
MST
