[PATCH v9 0/7] cgroup/cpuset: Add new cpuset partition type & empty effecitve cpus

[Waiman Long <longman@redhat.com>]

v9:
 - Add a new patch 1 to remove the child cpuset restriction on parent's
   "cpuset.cpus".
 - Relax initial root partition entry limitation to allow cpuset.cpus to
   overlap that of parent's.
 - An "isolated invalid" displayed type is added to
   cpuset.cpus.partition.
 - Resetting partition root to "member" will leave child partition root
   as invalid.
 - Update documentation and test accordingly.

v8:
 - Reorganize the patch series and rationalize the features and
   constraints of a partition.
 - Update patch descriptions and documentation accordingly.

v7:
 - Simplify the documentation patch (patch 5) as suggested by Tejun.
 - Fix a typo in patch 2 and improper commit log in patch 3.

This patchset includes one bug fix and four enhancements to the cpuset v2 code.

 Patch 1: Allow parent to set "cpuset.cpus" that may not be a superset
 of children's "cpuset.cpus" for default hierarchy.

 Patch 2: Enable partition with no task to have empty cpuset.cpus.effective.

 Patch 3: Refining the features and constraints of a cpuset partition
 clarifying what changes are allowed.

 Patch 4: Add a new partition state "isolated" to create a partition
 root without load balancing. This is for handling intermitten workloads
 that have a strict low latency requirement.

 Patch 5: Enable the "cpuset.cpus.partition" file to show the reason
 that causes invalid partition like "root invalid (No cpu available
 due to hotplug)".

Patch 6 updates the cgroup-v2.rst file accordingly. Patch 7 adds a new
cpuset test to test the new cpuset partition code.

Waiman Long (7):
  cgroup/cpuset: Don't let child cpusets restrict parent in default
    hierarchy
  cgroup/cpuset: Allow no-task partition to have empty
    cpuset.cpus.effective
  cgroup/cpuset: Refining features and constraints of a partition
  cgroup/cpuset: Add a new isolated cpus.partition type
  cgroup/cpuset: Show invalid partition reason string
  cgroup/cpuset: Update description of cpuset.cpus.partition in
    cgroup-v2.rst
  kselftest/cgroup: Add cpuset v2 partition root state test

 Documentation/admin-guide/cgroup-v2.rst       | 168 +++--
 kernel/cgroup/cpuset.c                        | 440 +++++++-----
 tools/testing/selftests/cgroup/Makefile       |   5 +-
 .../selftests/cgroup/test_cpuset_prs.sh       | 667 ++++++++++++++++++
 tools/testing/selftests/cgroup/wait_inotify.c |  87 +++
 5 files changed, 1142 insertions(+), 225 deletions(-)
 create mode 100755 tools/testing/selftests/cgroup/test_cpuset_prs.sh
 create mode 100644 tools/testing/selftests/cgroup/wait_inotify.c

-- 
2.27.0