On 8/7/26 4:59 AM, Shaojie Sun wrote:
Add a test case covering the bug fixed by
commit 345f40166694 ("cgroup/cpuset: Return only actually allocated
CPUs during partition invalidation"). The test verifies that when a
sibling partition root changes its cpuset.cpus to overlap with another
partition root, only actually allocated CPUs (effective_xcpus) are
returned to the parent, not all CPUs in cpus_allowed.
Signed-off-by: Shaojie Sun <[email protected]>
---
tools/testing/selftests/cgroup/test_cpuset_prs.sh | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/tools/testing/selftests/cgroup/test_cpuset_prs.sh
b/tools/testing/selftests/cgroup/test_cpuset_prs.sh
index 0d41aa0d343d..a44e92c94081 100755
--- a/tools/testing/selftests/cgroup/test_cpuset_prs.sh
+++ b/tools/testing/selftests/cgroup/test_cpuset_prs.sh
@@ -393,6 +393,12 @@ TEST_MATRIX=(
" C0-1:P1 . . P1:C2-3 C0-2 . . . 0
A1:0-1|XA1:0-1|B1:2-3 A1:P1|B1:P1"
" C0-1 . . P1:C2-3 C0-2 . . . 0 A1:0-1|B1:2-3
A1:P0|B1:P1"
+ # However, a partition root changing its own cpuset.cpus to overlap with
+ # a sibling partition root will invalidate itself. Only actually
allocated
+ # CPUs (effective_xcpus) should be returned to the parent, not all CPUs
+ # in cpus_allowed. The root cgroup effective CPUs must remain unchanged.
+ " C0-1:P1 . . C1-2:P1 . . . C0-1 0 A1:0-1
A1:P1|B1:P-1"
+
The cgroup hierarchy used by TEST_MATRIX may not suitable for doing this
kind of test as you can't easily check the state of the parent cgroup. I
would suggest you use the REMOTE_TEST_MATRIX hierarchy with p1, c11,
c12. After making c12 conflicts with c11, you can check p1 to see if it
has the right state.
Cheers,
Longman
# cpuset.cpus can overlap with sibling cpuset.cpus.exclusive but not
subsumed by it
" C0-3 . . C4-5 X5 . . . 0
A1:0-3|B1:4-5"
