diff options
| author | Jiazi Li <jqqlijiazi@gmail.com> | 2025-06-20 18:07:56 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-07-09 22:57:55 -0700 |
| commit | fed307b67c5bbb17b72c54816cd1bce61c23b4d7 (patch) | |
| tree | 549049ee8c625a9ec2eebcc5c49c0d35dab57a1e | |
| parent | caf728dfa7789f7096e8cd4341b4bf8f671f5c1d (diff) | |
kthread: update comment for __to_kthread
With commit 343f4c49f243 ("kthread: Don't allocate kthread_struct for init
and umh") and commit 753550eb0ce1 ("fork: Explicitly set PF_KTHREAD"), umh
task no longer have struct kthread and PF_KTHREAD flag.
Update the comment to describe what the current rules are to detect
is something is a kthread.
Link: https://lkml.kernel.org/r/20250620100801.23185-1-jqqlijiazi@gmail.com
Signed-off-by: Jiazi Li <jqqlijiazi@gmail.com>
Signed-off-by: mingzhu.wang <mingzhu.wang@transsion.com>
Suggested-by Eric W . Biederman <ebiederm@xmission.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | kernel/kthread.c | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/kernel/kthread.c b/kernel/kthread.c index 85fc068f0083..0e98b228a8ef 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -88,13 +88,12 @@ static inline struct kthread *to_kthread(struct task_struct *k) /* * Variant of to_kthread() that doesn't assume @p is a kthread. * - * Per construction; when: + * When "(p->flags & PF_KTHREAD)" is set the task is a kthread and will + * always remain a kthread. For kthreads p->worker_private always + * points to a struct kthread. For tasks that are not kthreads + * p->worker_private is used to point to other things. * - * (p->flags & PF_KTHREAD) && p->worker_private - * - * the task is both a kthread and struct kthread is persistent. However - * PF_KTHREAD on it's own is not, kernel_thread() can exec() (See umh.c and - * begin_new_exec()). + * Return NULL for any task that is not a kthread. */ static inline struct kthread *__to_kthread(struct task_struct *p) { |