kthread: add kthread_destroy_worker()

The current kthread worker users call flush() and stop() explicitly.
This function does the same plus it frees the kthread_worker struct
in one call.

It is supposed to be used together with kthread_create_worker*() that
allocates struct kthread_worker.

Link: http://lkml.kernel.org/r/1470754545-17632-7-git-send-email-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Petr Mladek 2016-10-11 13:55:33 -07:00 committed by Linus Torvalds
parent fbae2d44aa
commit 35033fe9cb
2 changed files with 25 additions and 0 deletions

View File

@ -136,4 +136,6 @@ bool kthread_queue_work(struct kthread_worker *worker,
void kthread_flush_work(struct kthread_work *work);
void kthread_flush_worker(struct kthread_worker *worker);
void kthread_destroy_worker(struct kthread_worker *worker);
#endif /* _LINUX_KTHREAD_H */

View File

@ -823,3 +823,26 @@ void kthread_flush_worker(struct kthread_worker *worker)
wait_for_completion(&fwork.done);
}
EXPORT_SYMBOL_GPL(kthread_flush_worker);
/**
* kthread_destroy_worker - destroy a kthread worker
* @worker: worker to be destroyed
*
* Flush and destroy @worker. The simple flush is enough because the kthread
* worker API is used only in trivial scenarios. There are no multi-step state
* machines needed.
*/
void kthread_destroy_worker(struct kthread_worker *worker)
{
struct task_struct *task;
task = worker->task;
if (WARN_ON(!task))
return;
kthread_flush_worker(worker);
kthread_stop(task);
WARN_ON(!list_empty(&worker->work_list));
kfree(worker);
}
EXPORT_SYMBOL(kthread_destroy_worker);