On Mon, Jun 07, 2021 at 11:13:04AM -0700, Dave Jiang wrote: > So in step 1, we 'tag' the wq to be dedicated to guest usage and put the > hardware wq into enable state. For a dedicated mode wq, we can definitely > just register directly and skip the mdev step. For a shared wq mode, we can > have multiple mdev running on top of a single wq. So we need some way to > create more mdevs. We can either go with the existing established creation > path by mdev, or invent something custom for the driver as Jason suggested > to accomodate additional virtual devices for guests. We implemented the mdev > path originally with consideration of mdev is established and has a known > interface already. It sounds like you could just as easially have a 'create new vfio' file under the idxd sysfs.. Especially since you already have a bus and dynamic vfio specific things being created on this bus. Have you gone over this with Dan? > I think things become more complicated when we go from a dedicated wq to > shared wq where the relationship of wq : mdev is 1 : 1 goes to 1 : N. Also > needing to keep a consistent user config experience is desired, especially > we already have such behavior since kernel 5.6 for host usages. So we really > need try to avoid doing wq configuration differently just for "mdev" wqs. In > the case suggested above, we basically just flipped the configuration steps. > Mdev is first created through mdev sysfs interface. And then the device > paramters are configured. Where for us, we configure the device parameter > first, and then create the mdev. But in the end, it's still the hybrid mdev > setup right? So you don't even use mdev to configure anything? Yuk. Jason
