On Tue, Aug 10, 2021 at 11:06:05PM -0400, Waiman Long wrote: > Currently, a parent partition root cannot distribute all its CPUs to > child partition roots with no CPUs left. However in some use cases, > a management application may want to create a parent partition root as > a management unit with no task associated with it and has all its CPUs > distributed to various child partition roots dynamically according to > their needs. Leaving a cpu in the parent partition root in such a case is > now a waste. > > To accommodate such use cases, a parent partition root can now have > all its CPUs distributed to its child partition roots as long as: > 1) it is not the top cpuset; and > 2) there is no task directly associated with the parent. > > Once an empty parent partition root is formed, no new task can be moved > into it. The above are already enforced by cgroup2 core, right? No intermediate cgroup with controllers enabled can have processes. From controllers' POV, only leaves can have processes. Thanks. -- tejun
