From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Tue, 13 Mar 2018 11:31:09 +0100
Subject: Revert "block: blk-mq: Use swait"
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git
Git-commit: ca3fd6cf836739fd59eac2f7a9b0261365e818bb
Patch-mainline: Queued in subsystem maintainer repository
References: SLE Realtime Extension

This reverts commit "block: blk-mq: Use swait". The issue remains but
will be fixed differently.

Cc: stable-rt@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Mike Galbraith <mgalbraith@suse.de>
---
 block/blk-core.c       |    8 ++++----
 block/blk-mq.c         |    6 +++---
 include/linux/blkdev.h |    2 +-
 3 files changed, 8 insertions(+), 8 deletions(-)

--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -713,7 +713,7 @@ void blk_set_queue_dying(struct request_
 	}
 
 	/* Make blk_queue_enter() reexamine the DYING flag. */
-	swake_up_all(&q->mq_freeze_wq);
+	wake_up_all(&q->mq_freeze_wq);
 }
 EXPORT_SYMBOL_GPL(blk_set_queue_dying);
 
@@ -953,7 +953,7 @@ int blk_queue_enter(struct request_queue
 		 */
 		smp_rmb();
 
-		swait_event(q->mq_freeze_wq,
+		wait_event(q->mq_freeze_wq,
 			   (atomic_read(&q->mq_freeze_depth) == 0 &&
 			    (preempt || !blk_queue_preempt_only(q))) ||
 			   blk_queue_dying(q));
@@ -972,7 +972,7 @@ static void blk_queue_usage_counter_rele
 	struct request_queue *q =
 		container_of(ref, struct request_queue, q_usage_counter);
 
-	swake_up_all(&q->mq_freeze_wq);
+	wake_up_all(&q->mq_freeze_wq);
 }
 
 static void blk_rq_timed_out_timer(struct timer_list *t)
@@ -1063,7 +1063,7 @@ struct request_queue *blk_alloc_queue_no
 	q->bypass_depth = 1;
 	queue_flag_set_unlocked(QUEUE_FLAG_BYPASS, q);
 
-	init_swait_queue_head(&q->mq_freeze_wq);
+	init_waitqueue_head(&q->mq_freeze_wq);
 	mutex_init(&q->mq_freeze_lock);
 
 	/*
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -153,14 +153,14 @@ EXPORT_SYMBOL_GPL(blk_freeze_queue_start
 
 void blk_mq_freeze_queue_wait(struct request_queue *q)
 {
-	swait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter));
+	wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter));
 }
 EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_wait);
 
 int blk_mq_freeze_queue_wait_timeout(struct request_queue *q,
 				     unsigned long timeout)
 {
-	return swait_event_timeout(q->mq_freeze_wq,
+	return wait_event_timeout(q->mq_freeze_wq,
 					percpu_ref_is_zero(&q->q_usage_counter),
 					timeout);
 }
@@ -204,7 +204,7 @@ void blk_mq_unfreeze_queue(struct reques
 	WARN_ON_ONCE(freeze_depth < 0);
 	if (!freeze_depth) {
 		percpu_ref_reinit(&q->q_usage_counter);
-		swake_up_all(&q->mq_freeze_wq);
+		wake_up_all(&q->mq_freeze_wq);
 	}
 	mutex_unlock(&q->mq_freeze_lock);
 }
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -654,7 +654,7 @@ struct request_queue {
 	struct throtl_data *td;
 #endif
 	struct rcu_head		rcu_head;
-	struct swait_queue_head	mq_freeze_wq;
+	wait_queue_head_t	mq_freeze_wq;
 	struct percpu_ref	q_usage_counter;
 	struct list_head	all_q_node;