kthread: kthread worker API cleanup

A good practice is to prefix the names of functions by the name
of the subsystem.

The kthread worker API is a mix of classic kthreads and workqueues.  Each
worker has a dedicated kthread.  It runs a generic function that process
queued works.  It is implemented as part of the kthread subsystem.

This patch renames the existing kthread worker API to use
the corresponding name from the workqueues API prefixed by
kthread_:

__init_kthread_worker()		-> __kthread_init_worker()
init_kthread_worker()		-> kthread_init_worker()
init_kthread_work()		-> kthread_init_work()
insert_kthread_work()		-> kthread_insert_work()
queue_kthread_work()		-> kthread_queue_work()
flush_kthread_work()		-> kthread_flush_work()
flush_kthread_worker()		-> kthread_flush_worker()

Note that the names of DEFINE_KTHREAD_WORK*() macros stay
as they are. It is common that the "DEFINE_" prefix has
precedence over the subsystem names.

Note that INIT() macros and init() functions use different
naming scheme. There is no good solution. There are several
reasons for this solution:

  + "init" in the function names stands for the verb "initialize"
    aka "initialize worker". While "INIT" in the macro names
    stands for the noun "INITIALIZER" aka "worker initializer".

  + INIT() macros are used only in DEFINE() macros

  + init() functions are used close to the other kthread()
    functions. It looks much better if all the functions
    use the same scheme.

  + There will be also kthread_destroy_worker() that will
    be used close to kthread_cancel_work(). It is related
    to the init() function. Again it looks better if all
    functions use the same naming scheme.

  + there are several precedents for such init() function
    names, e.g. amd_iommu_init_device(), free_area_init_node(),
    jump_label_init_type(),  regmap_init_mmio_clk(),

  + It is not an argument but it was inconsistent even before.

[arnd@arndb.de: fix linux-next merge conflict]
 Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
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: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 17 insertions, 16 deletions

diff --git a/kernel/kthread.c b/kernel/kthread.c
index 7e77b72..c52a05a 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -540,7 +540,7 @@ int kthreadd(void *unused)
 	return 0;
 }
 
-void __init_kthread_worker(struct kthread_worker *worker,
+void __kthread_init_worker(struct kthread_worker *worker,
 				const char *name,
 				struct lock_class_key *key)
 {
@@ -549,7 +549,7 @@ void __init_kthread_worker(struct kthread_worker *worker,
 	INIT_LIST_HEAD(&worker->work_list);
 	worker->task = NULL;
 }
-EXPORT_SYMBOL_GPL(__init_kthread_worker);
+EXPORT_SYMBOL_GPL(__kthread_init_worker);
 
 /**
  * kthread_worker_fn - kthread function to process kthread_worker
@@ -606,7 +606,7 @@ repeat:
 EXPORT_SYMBOL_GPL(kthread_worker_fn);
 
 /* insert @work before @pos in @worker */
-static void insert_kthread_work(struct kthread_worker *worker,
+static void kthread_insert_work(struct kthread_worker *worker,
 			       struct kthread_work *work,
 			       struct list_head *pos)
 {
@@ -619,7 +619,7 @@ static void insert_kthread_work(struct kthread_worker *worker,
 }
 
 /**
- * queue_kthread_work - queue a kthread_work
+ * kthread_queue_work - queue a kthread_work
  * @worker: target kthread_worker
  * @work: kthread_work to queue
  *
@@ -627,7 +627,7 @@ static void insert_kthread_work(struct kthread_worker *worker,
  * must have been created with kthread_worker_create().  Returns %true
  * if @work was successfully queued, %false if it was already pending.
  */
-bool queue_kthread_work(struct kthread_worker *worker,
+bool kthread_queue_work(struct kthread_worker *worker,
 			struct kthread_work *work)
 {
 	bool ret = false;
@@ -635,13 +635,13 @@ bool queue_kthread_work(struct kthread_worker *worker,
 
 	spin_lock_irqsave(&worker->lock, flags);
 	if (list_empty(&work->node)) {
-		insert_kthread_work(worker, work, &worker->work_list);
+		kthread_insert_work(worker, work, &worker->work_list);
 		ret = true;
 	}
 	spin_unlock_irqrestore(&worker->lock, flags);
 	return ret;
 }
-EXPORT_SYMBOL_GPL(queue_kthread_work);
+EXPORT_SYMBOL_GPL(kthread_queue_work);
 
 struct kthread_flush_work {
 	struct kthread_work	work;
@@ -656,12 +656,12 @@ static void kthread_flush_work_fn(struct kthread_work *work)
 }
 
 /**
- * flush_kthread_work - flush a kthread_work
+ * kthread_flush_work - flush a kthread_work
  * @work: work to flush
  *
  * If @work is queued or executing, wait for it to finish execution.
  */
-void flush_kthread_work(struct kthread_work *work)
+void kthread_flush_work(struct kthread_work *work)
 {
 	struct kthread_flush_work fwork = {
 		KTHREAD_WORK_INIT(fwork.work, kthread_flush_work_fn),
@@ -682,9 +682,10 @@ retry:
 	}
 
 	if (!list_empty(&work->node))
-		insert_kthread_work(worker, &fwork.work, work->node.next);
+		kthread_insert_work(worker, &fwork.work, work->node.next);
 	else if (worker->current_work == work)
-		insert_kthread_work(worker, &fwork.work, worker->work_list.next);
+		kthread_insert_work(worker, &fwork.work,
+				    worker->work_list.next);
 	else
 		noop = true;
 
@@ -693,23 +694,23 @@ retry:
 	if (!noop)
 		wait_for_completion(&fwork.done);
 }
-EXPORT_SYMBOL_GPL(flush_kthread_work);
+EXPORT_SYMBOL_GPL(kthread_flush_work);
 
 /**
- * flush_kthread_worker - flush all current works on a kthread_worker
+ * kthread_flush_worker - flush all current works on a kthread_worker
  * @worker: worker to flush
  *
  * Wait until all currently executing or pending works on @worker are
  * finished.
  */
-void flush_kthread_worker(struct kthread_worker *worker)
+void kthread_flush_worker(struct kthread_worker *worker)
 {
 	struct kthread_flush_work fwork = {
 		KTHREAD_WORK_INIT(fwork.work, kthread_flush_work_fn),
 		COMPLETION_INITIALIZER_ONSTACK(fwork.done),
 	};
 
-	queue_kthread_work(worker, &fwork.work);
+	kthread_queue_work(worker, &fwork.work);
 	wait_for_completion(&fwork.done);
 }
-EXPORT_SYMBOL_GPL(flush_kthread_worker);
+EXPORT_SYMBOL_GPL(kthread_flush_worker);