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>

2 files changed, 5 insertions, 5 deletions

diff --git a/drivers/md/dm-rq.c b/drivers/md/dm-rq.c
index 5eacce1ef88b..dc75bea0d541 100644
--- a/drivers/md/dm-rq.c
+++ b/drivers/md/dm-rq.c
@@ -581,7 +581,7 @@ static void init_tio(struct dm_rq_target_io *tio, struct request *rq,
 	if (!md->init_tio_pdu)
 		memset(&tio->info, 0, sizeof(tio->info));
 	if (md->kworker_task)
-		init_kthread_work(&tio->work, map_tio_request);
+		kthread_init_work(&tio->work, map_tio_request);
 }
 
 static struct dm_rq_target_io *dm_old_prep_tio(struct request *rq,
@@ -831,7 +831,7 @@ static void dm_old_request_fn(struct request_queue *q)
 		tio = tio_from_request(rq);
 		/* Establish tio->ti before queuing work (map_tio_request) */
 		tio->ti = ti;
-		queue_kthread_work(&md->kworker, &tio->work);
+		kthread_queue_work(&md->kworker, &tio->work);
 		BUG_ON(!irqs_disabled());
 	}
 }
@@ -853,7 +853,7 @@ int dm_old_init_request_queue(struct mapped_device *md)
 	blk_queue_prep_rq(md->queue, dm_old_prep_fn);
 
 	/* Initialize the request-based DM worker thread */
-	init_kthread_worker(&md->kworker);
+	kthread_init_worker(&md->kworker);
 	md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker,
 				       "kdmwork-%s", dm_device_name(md));
 	if (IS_ERR(md->kworker_task))
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index be35258324c1..147af9536d0c 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1891,7 +1891,7 @@ static void __dm_destroy(struct mapped_device *md, bool wait)
 	spin_unlock_irq(q->queue_lock);
 
 	if (dm_request_based(md) && md->kworker_task)
-		flush_kthread_worker(&md->kworker);
+		kthread_flush_worker(&md->kworker);
 
 	/*
 	 * Take suspend_lock so that presuspend and postsuspend methods
@@ -2147,7 +2147,7 @@ static int __dm_suspend(struct mapped_device *md, struct dm_table *map,
 	if (dm_request_based(md)) {
 		dm_stop_queue(md->queue);
 		if (md->kworker_task)
-			flush_kthread_worker(&md->kworker);
+			kthread_flush_worker(&md->kworker);
 	}
 
 	flush_workqueue(md->wq);