v12: - Change patch 1 to enable update_tasks_cpumask() for top_cpuset except for percpu kthreads. - Add 2 more patches to make exclusivity rule violations invalidate the partition and its siblings instead of failing the change to make it consistent with other cpuset changes. - Update documentation and test script accordingly.
v11: - Fix incorrect spacing in patch 7 and include documentation suggestions by Michal. - Move partition_is_populated() check to the last one in list of conditions to be checked.
v10: - Relax constraints for changes made to "cpuset.cpus" and "cpuset.cpus.partition" as suggested. Now almost all changes are allowed. - Add patch 1 to signal that we may need to do additional work in the future to relax the constraint that tasks' cpumask may need some adjustment if child partitions are present. - Add patch 2 for miscellaneous cleanups.
The first patch fixes the problem that tasks in the top_cpuset will not have its cpus_mask properly set to reflect the reduced set of cpus available in the top_cpuset when a partition is enabled.
This patchset also includes the following enhancements to the cpuset v2 partition code.
1) Allow partitions that have no task to have empty effective cpus. 2) Relax the constraints on what changes are allowed in cpuset.cpus and cpuset.cpus.partition. However, the partition remain invalid until the constraints of a valid partition root is satisfied. 3) Add a new "isolated" partition type for partitions with no load balancing which is available in v1 but not yet in v2. 4) Allow the reading of cpuset.cpus.partition to include a reason string as to why the partition remain invalid.
In addition, the cgroup-v2.rst documentation file is updated and a self test is added to verify the correctness the partition code.
Waiman Long (10): cgroup/cpuset: Enable update_tasks_cpumask() on top_cpuset cgroup/cpuset: Miscellaneous cleanups & add helper functions cgroup/cpuset: Allow no-task partition to have empty cpuset.cpus.effective cgroup/cpuset: Relax constraints to partition & cpus changes cgroup/cpuset: Add a new isolated cpus.partition type cgroup/cpuset: Show invalid partition reason string cgroup/cpuset: Relocate a code block in validate_change() cgroup/cpuset: Make partition invalid if cpumask change violates exclusivity rule 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 | 150 ++-- kernel/cgroup/cpuset.c | 817 ++++++++++++------ tools/testing/selftests/cgroup/.gitignore | 1 + tools/testing/selftests/cgroup/Makefile | 5 +- .../selftests/cgroup/test_cpuset_prs.sh | 674 +++++++++++++++ tools/testing/selftests/cgroup/wait_inotify.c | 87 ++ 6 files changed, 1385 insertions(+), 349 deletions(-) create mode 100755 tools/testing/selftests/cgroup/test_cpuset_prs.sh create mode 100644 tools/testing/selftests/cgroup/wait_inotify.c