Hello, Waiman. My apologies for the delay. On Mon, Aug 27, 2018 at 01:50:18PM -0400, Waiman Long wrote: > My current code has explicitly assumed the following relationship for > partition root. > > cpus_allowed = effective_cpus + reserved_cpus > > Also effective_cpus cannot be empty. Specifically, cpus_allowed has to > be equal to effective_cpus before a cpuset can be made a partition root. > > Any changes that break the above conditions will turn off the partition > flag forcefully. The only exception is cpu offlining where cpus_allowed > > effective_cpus + reserved_cpus can happen. > > One reason for doing so is because reserved_cpus is hidden. So the main > way to infer that is to do cpus_allowed - effective_cpus. > > It is probably doable to make cpus_allowed >= effective_cpus + > reserved_cpus in general, but we may need to expose reserved_cpus as a > read-only file, for instance. There may also be other complications that > we will need to take care of if this is supported. My current preference > is to not doing that unless there is compelling reason to do so. So, if we're gonna make this hierarchical, I think it probably would be better to go in all the way. It's kinda weird to mix the two approaches - the normal cpuset operation following the usual convention (it'd be really great to fix the removal part too) and parition code doing something else. I think adding another interface file should be fine here. Thanks. -- tejun
