On Wed, Jan 16, 2013 at 10:14:33AM -0600, Anthony Liguori wrote: > "Michael S. Tsirkin" <mst@xxxxxxxxxx> writes: > > > On Wed, Jan 16, 2013 at 09:09:49AM -0600, Anthony Liguori wrote: > >> Jason Wang <jasowang@xxxxxxxxxx> writes: > >> > >> > On 01/15/2013 03:44 AM, Anthony Liguori wrote: > >> >> Jason Wang <jasowang@xxxxxxxxxx> writes: > >> >> > >> >>> Hello all: > >> >>> > >> >>> This seires is an update of last version of multiqueue virtio-net support. > >> >>> > >> >>> Recently, linux tap gets multiqueue support. This series implements basic > >> >>> support for multiqueue tap, nic and vhost. Then use it as an infrastructure to > >> >>> enable the multiqueue support for virtio-net. > >> >>> > >> >>> Both vhost and userspace multiqueue were implemented for virtio-net, but > >> >>> userspace could be get much benefits since dataplane like parallized mechanism > >> >>> were not implemented. > >> >>> > >> >>> User could start a multiqueue virtio-net card through adding a "queues" > >> >>> parameter to tap. > >> >>> > >> >>> ./qemu -netdev tap,id=hn0,queues=2,vhost=on -device virtio-net-pci,netdev=hn0 > >> >>> > >> >>> Management tools such as libvirt can pass multiple pre-created fds through > >> >>> > >> >>> ./qemu -netdev tap,id=hn0,queues=2,fd=X,fd=Y -device > >> >>> virtio-net-pci,netdev=hn0 > >> >> I'm confused/frightened that this syntax works. You shouldn't be > >> >> allowed to have two values for the same property. Better to have a > >> >> syntax like fd[0]=X,fd[1]=Y or something along those lines. > >> > > >> > Yes, but this what current a StringList type works for command line. > >> > Some other parameters such as dnssearch, hostfwd and guestfwd have > >> > already worked in this way. Looks like your suggestions need some > >> > extension on QemuOps visitor, maybe we can do this on top. > >> > >> It's a silly syntax and breaks compatibility. This is valid syntax: > >> > >> -net tap,fd=3,fd=4 > >> > >> In this case, it means 'fd=4' because the last fd overwrites the first > >> one. > >> > >> Now you've changed it to mean something else. Having one thing mean > >> something in one context, but something else in another context is > >> terrible interface design. > >> > >> Regards, > >> > >> Anthony Liguori > > > > Aha so just renaming the field 'fds' would address this issue? > > No, you still have the problem of different meanings. > > -netdev tap,fd=X,fd=Y > > -netdev tap,fds=X,fds=Y > > Would have wildly different behavior. fd=X,fd=Y is more a bug than a feature. It could have failed just as well. > Just do: > > -netdev tap,fds=X:Y > > And then we're staying consistent wrt the interpretation of multiple > properties of the same name. > > Regards, > > Anthony Liguori Issue is ':' would only work for a list of numbers. As Jason points out StringList is already used - do we really want to invent yet another syntax for a list that will work only for this case? -- MST -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
