v6:
- Rebase on top of the latest v7.0 pre-RC linux tree.
- Add another fix patch to fix found during code inspection.
- Revert back to the v4 idea of just deferring the housekeeping_update()
call to workqueue to make it simple as v5 change will add quite a
bit more complexity to the cpuset code.
v5:
- https://lore.kernel.org/lkml/[email protected]/
After booting the latest linux debug kernel with the latest cgroup
changes as well as Federic's "cpuset/isolation: Honour kthreads
preferred affinity" patch series [1] merged on top and running the
test-cpuset-prs.sh test, a circular locking dependency lockdep splat
was reported. See patch 5 for details.
To fix this issue, the cpuset code is modified to not call
housekeeping_update() with cpu_hotplug_lock held. The cpuset hotplug
code is also modified to defer the housekeeping_update() call, if needed,
to workqueue. A new top level cpuset_top_mutex is added to have more
exclusion control.
With these changes in place, the cpuset test ran to completion with no
failure and no lockdep splat.
[1] https://lore.kernel.org/lkml/[email protected]/
Waiman Long (8):
cgroup/cpuset: Fix incorrect change to effective_xcpus in
partition_xcpus_del()
cgroup/cpuset: Fix incorrect use of cpuset_update_tasks_cpumask() in
update_cpumasks_hier()
cgroup/cpuset: Clarify exclusion rules for cpuset internal variables
cgroup/cpuset: Set isolated_cpus_updating only if isolated_cpus is
changed
kselftest/cgroup: Simplify test_cpuset_prs.sh by removing "S+" command
cgroup/cpuset: Move housekeeping_update()/rebuild_sched_domains()
together
cgroup/cpuset: Defer housekeeping_update() calls from CPU hotplug to
workqueue
cgroup/cpuset: Call housekeeping_update() without holding
cpus_read_lock
kernel/cgroup/cpuset.c | 220 +++++++++++------
kernel/sched/isolation.c | 4 +-
kernel/time/timer_migration.c | 4 +-
.../selftests/cgroup/test_cpuset_prs.sh | 225 +++++++++---------
4 files changed, 265 insertions(+), 188 deletions(-)
--
2.53.0
