cgroup/cpuset: Remove remote_partition_check() & make update_cpumasks_hier() handle remote partition

Browse source

Currently, changes in exclusive CPUs are being handled in
remote_partition_check() by disabling conflicting remote partitions.
However, that may lead to results unexpected by the users. Fix
this problem by removing remote_partition_check() and making
update_cpumasks_hier() handle changes in descendant remote partitions
properly.

The compute_effective_exclusive_cpumask() function is enhanced to check
the exclusive_cpus and effective_xcpus from siblings and excluded them
in its effective exclusive CPUs computation and return a value to show if
there is any sibling conflicts.  This is somewhat like the cpu_exclusive
flag check in validate_change(). This is the initial step to enable us
to retire the use of cpu_exclusive flag in cgroup v2 in the future.

One of the tests in the TEST_MATRIX of the test_cpuset_prs.sh
script has to be updated due to changes in the way a child remote
partition root is being handled (updated instead of invalidation)
in update_cpumasks_hier().

Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

...

This commit is contained in:

Waiman Long 2025-03-30 17:52:42 -04:00 • committed by Tejun Heo

parent 8bf450f3ae

commit f62a5d3936

2 changed files with 143 additions and 119 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

262

kernel/cgroup/cpuset.c

View file

4

tools/testing/selftests/cgroup/test_cpuset_prs.sh

View file