On 1/15/07, Balbir Singh <balbir at in.ibm.com> wrote: > > While writing/extending the cpuacct container, I found it useful to > know if the container resource group we are controlling is really mounted. > Controllers can try and avoid doing work when not mounted and start > when the subsystem is mounted. Also, without these callbacks, one has no > definite way of checking if the top_container is dummy or for real. > That's somewhat intentional - my aim was that the controllers shouldn't really care whether they're connected to the default hierarchy or have been bound to some mounted hierarchy. Having said thay, they can determine it by checking <foo>_subsys.hierarchy if they really want to. If that's 0 then they're in the default hierarchy (and can assume that all tasks are in one top-level container). Paul