diff options
| author | Frederic Weisbecker <frederic@kernel.org> | 2025-06-04 14:02:40 +0200 |
|---|---|---|
| committer | Frederic Weisbecker <frederic@kernel.org> | 2026-02-03 15:23:35 +0100 |
| commit | e894f633980804a528a2d6996c4ea651df631632 (patch) | |
| tree | 8bd64eb9ec9b30da5deba98bccc4713a1280f146 /kernel/cgroup | |
| parent | 79c0abaf06fca6e715cf792daed580542fc4a2c4 (diff) | |
kthread: Honour kthreads preferred affinity after cpuset changes
When cpuset isolated partitions get updated, unbound kthreads get
indifferently affine to all non isolated CPUs, regardless of their
individual affinity preferences.
For example kswapd is a per-node kthread that prefers to be affine to
the node it refers to. Whenever an isolated partition is created,
updated or deleted, kswapd's node affinity is going to be broken if any
CPU in the related node is not isolated because kswapd will be affine
globally.
Fix this with letting the consolidated kthread managed affinity code do
the affinity update on behalf of cpuset.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Waiman Long <longman@redhat.com>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Marco Crivellari <marco.crivellari@suse.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Waiman Long <longman@redhat.com>
Cc: cgroups@vger.kernel.org
Diffstat (limited to 'kernel/cgroup')
| -rw-r--r-- | kernel/cgroup/cpuset.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 801694de82a3..9a8292b7c7f1 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -1208,11 +1208,10 @@ void cpuset_update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus) if (top_cs) { /* + * PF_KTHREAD tasks are handled by housekeeping. * PF_NO_SETAFFINITY tasks are ignored. - * All per cpu kthreads should have PF_NO_SETAFFINITY - * flag set, see kthread_set_per_cpu(). */ - if (task->flags & PF_NO_SETAFFINITY) + if (task->flags & (PF_KTHREAD | PF_NO_SETAFFINITY)) continue; cpumask_andnot(new_cpus, possible_mask, subpartitions_cpus); } else { |