[dm-devel] [RFC PATCH] multipath: flush workqueue only in necessary

[wuzhouhui]

When flush works belong a specific multipath, we flush workqueue only
in necessary.

(That's my first time to send a patch, please remind me if anything
wrong)

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index f7810cc..0f14732 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1154,9 +1154,10 @@ static void flush_multipath_work(struct multipath *m)
 	set_bit(MPATHF_PG_INIT_DISABLED, &m->flags);
 	smp_mb__after_atomic();
 
-	flush_workqueue(kmpath_handlerd);
+	if (atomic_read(&m->pg_init_in_progress))
+		flush_workqueue(kmpath_handlerd);
 	multipath_wait_for_pg_init_completion(m);
-	flush_workqueue(kmultipathd);
+	flush_work(&m->process_queued_bios);
 	flush_work(&m->trigger_event);
 
 	clear_bit(MPATHF_PG_INIT_DISABLED, &m->flags);