On Wed, Mar 03, 2021 at 06:55:13PM -0800, Jacob Pan wrote: > Hi Vipin, > > On Tue, 2 Mar 2021 00:17:05 -0800, Vipin Sharma <vipinsh@xxxxxxxxxx> wrote: > > > +Migration and Ownership > > +~~~~~~~~~~~~~~~~~~~~~~~ > > + > > +A miscellaneous scalar resource is charged to the cgroup in which it is > > used +first, and stays charged to that cgroup until that resource is > > freed. Migrating +a process to a different cgroup does not move the > > charge to the destination +cgroup where the process has moved. > > + > I am trying to see if IOASIDs cgroup can also fit in this misc controller > as yet another resource type. > https://lore.kernel.org/linux-iommu/20210303131726.7a8cb169@jacob-builder/T/#u > However, unlike sev IOASIDs need to be migrated if the process is moved to > another cgroup. i.e. charge the destination and uncharge the source. > > Do you think this behavior can be achieved by differentiating resource > types? i.e. add attach callbacks for certain types. Having a single misc > interface seems cleaner than creating another controller. I think it makes sense to add support for migration for the resources which need it. Resources like SEV, SEV-ES will not participate in migration and won't stop can_attach() to succeed, other resources which need migration will allow or stop based on their limits and capacity in the destination.
