Re: [PATCH-next v3 0/3] cgroup/cpuset: Support multiple destination cpusets for cpuset_*attach()

From: Waiman Long

Date: Thu Jul 16 2026 - 15:48:21 EST



On 7/16/26 3:42 PM, Tejun Heo wrote:
Hello,

On Sun, Jul 12, 2026 at 07:55:07PM -0400, Waiman Long wrote:
Michal Koutný (1):
selftests/cgroup: Add test for cpuset affinity on controller disable

Waiman Long (2):
cgroup/cpuset: Support multiple destination cpusets for
cpuset_*attach()
cgroup/cpuset: Handle the special case of non-moving tasks in
cpuset_can_attach()
Applied 1-3 to cgroup/for-7.3.

While applying, fixed a comment typo in patch 1:

- else if (cs->dl_bw_cpu >= 0) /* && cacnel */
+ else if (cs->dl_bw_cpu >= 0) /* && cancel */

The following selftest issues remain. Let's address them with follow-up
patches:

- cpu_set_equal() iterates sizeof(mask) bytes rather than bits, so only
CPUs 0-7 are compared, and the assert compares a byte count against
CPU_SETSIZE bits so it always holds.

- thread_b doesn't wait for thread_a before advancing test_phase to
AFFINITY_THREADS_READY, so the main thread can read affinity_a_before
before thread_a has written it.

- On a machine which doesn't have both CPUs 0 and 1 online, the test
fails instead of skipping.

Will fix the selftest in a follow-up patch.

Cheers,
Longman