Re: [PATCHSET cgroup/for-3.15] cgroup: prepare for the default unified hierarchy

[Tejun Heo <tj@kernel.org>]

On Thu, Mar 13, 2014 at 03:50:02PM -0400, Tejun Heo wrote:
> The planned unified hierarchy is just around the corner.  We're gonna
> repurpose the dummy hierarchy to serve as the default unified
> hierarchy.  Controllers which aren't attached to other hierarchies are
> already automatically bound to the dummy hierarchy; however, the dummy
> hierarchy is minimally initialized during boot and can't currently act
> as a full hierarchy.
> 
> This patchset gradually turns the dummy hierarchy into fully
> functional default one and makes it mountable via selecting
> sane_behavior without any subsystems specified.  While this patchset
> does make the default hierarchy mountable, the unified hierarchy
> functionality isn't implemented yet and cgroup creation in the default
> hierarchy is rejected for now.
> 
> This lays down all the boilerplate work for the unified hierarchy.
> The next patchset will implement the actual unified functionality.
> 
> This patchset contains the following eleven patches.
> 
>  0001-cgroup-cgroup-subsys-should-be-cleared-after-the-css.patch
>  0002-cgroup-relocate-setting-of-CGRP_DEAD.patch
>  0003-cgroup-reorganize-cgroup-bootstrapping.patch
>  0004-cgroup-use-cgroup_setup_root-to-initialize-cgroup_du.patch
>  0005-cgroup-remove-NULL-checks-from-pr_cont_-cgroup_-name.patch
>  0006-cgroup-treat-cgroup_dummy_root-as-an-equivalent-hier.patch
>  0007-cgroup-move-subsys_mask-from-cgroupfs_root-to-cgroup.patch
>  0008-cgroup-rename-cgroup_dummy_root-and-related-names.patch
>  0009-cgroup-drop-const-from-buffer-of-cftype-write_string.patch
>  0010-cgroup-make-cgrp_dfl_root-mountable.patch
>  0011-cgroup-implement-CFTYPE_ONLY_ON_DFL.patch

Applied 0002-0011 to libata/for-3.15.  0001 has the possibility to
make css iterators malfunction as they don't exect the csses to be
NULL.  It will be applied after iterators are updated to handle NULL
csses.

Thanks.

-- 
tejun