diff options
| author | Frederic Weisbecker <frederic@kernel.org> | 2025-06-18 16:52:04 +0200 |
|---|---|---|
| committer | Frederic Weisbecker <frederic@kernel.org> | 2026-02-03 15:23:35 +0100 |
| commit | 60ba9c38b9316efa3eb1c8a927bee6f8a4f101a5 (patch) | |
| tree | 534ef46b9523bb94561f419aefc76568435b67c4 | |
| parent | e894f633980804a528a2d6996c4ea651df631632 (diff) | |
kthread: Comment on the purpose and placement of kthread_affine_node() call
It may not appear obvious why kthread_affine_node() is not called before
the kthread creation completion instead of after the first wake-up.
The reason is that kthread_affine_node() applies a default affinity
behaviour that only takes place if no affinity preference have already
been passed by the kthread creation call site.
Add a comment to clarify that.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.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>
| -rw-r--r-- | kernel/kthread.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/kernel/kthread.c b/kernel/kthread.c index 03008154249c..51f419139dea 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -453,6 +453,10 @@ static int kthread(void *_create) self->started = 1; + /* + * Apply default node affinity if no call to kthread_bind[_mask]() nor + * kthread_affine_preferred() was issued before the first wake-up. + */ if (!(current->flags & PF_NO_SETAFFINITY) && !self->preferred_affinity) kthread_affine_node(); |