sched/wait: Rename wait_queue_t => wait_queue_entry_t

Rename:

	wait_queue_t		=>	wait_queue_entry_t

'wait_queue_t' was always a slight misnomer: its name implies that it's a "queue",
but in reality it's a queue *entry*. The 'real' queue is the wait queue head,
which had to carry the name.

Start sorting this out by renaming it to 'wait_queue_entry_t'.

This also allows the real structure name 'struct __wait_queue' to
lose its double underscore and become 'struct wait_queue_entry',
which is the more canonical nomenclature for such data types.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/block/blk-mq.c b/block/blk-mq.c
index bb66c96..a083f95 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -926,7 +926,7 @@ static bool reorder_tags_to_front(struct list_head *list)
 	return first != NULL;
 }
 
-static int blk_mq_dispatch_wake(wait_queue_t *wait, unsigned mode, int flags,
+static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode, int flags,
 				void *key)
 {
 	struct blk_mq_hw_ctx *hctx;
diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index 17676f4..5f3a37c 100644
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -503,7 +503,7 @@ static inline unsigned int get_limit(struct rq_wb *rwb, unsigned long rw)
 }
 
 static inline bool may_queue(struct rq_wb *rwb, struct rq_wait *rqw,
-			     wait_queue_t *wait, unsigned long rw)
+			     wait_queue_entry_t *wait, unsigned long rw)
 {
 	/*
 	 * inc it here even if disabled, since we'll dec it at completion.
diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c
index b9faabc..b95d6bd 100644
--- a/block/kyber-iosched.c
+++ b/block/kyber-iosched.c
@@ -99,7 +99,7 @@ struct kyber_hctx_data {
 	struct list_head rqs[KYBER_NUM_DOMAINS];
 	unsigned int cur_domain;
 	unsigned int batching;
-	wait_queue_t domain_wait[KYBER_NUM_DOMAINS];
+	wait_queue_entry_t domain_wait[KYBER_NUM_DOMAINS];
 	atomic_t wait_index[KYBER_NUM_DOMAINS];
 };
 
@@ -507,7 +507,7 @@ static void kyber_flush_busy_ctxs(struct kyber_hctx_data *khd,
 	}
 }
 
-static int kyber_domain_wake(wait_queue_t *wait, unsigned mode, int flags,
+static int kyber_domain_wake(wait_queue_entry_t *wait, unsigned mode, int flags,
 			     void *key)
 {
 	struct blk_mq_hw_ctx *hctx = READ_ONCE(wait->private);
@@ -523,7 +523,7 @@ static int kyber_get_domain_token(struct kyber_queue_data *kqd,
 {
 	unsigned int sched_domain = khd->cur_domain;
 	struct sbitmap_queue *domain_tokens = &kqd->domain_tokens[sched_domain];
-	wait_queue_t *wait = &khd->domain_wait[sched_domain];
+	wait_queue_entry_t *wait = &khd->domain_wait[sched_domain];
 	struct sbq_wait_state *ws;
 	int nr;
 
@@ -734,7 +734,7 @@ static int kyber_##name##_waiting_show(void *data, struct seq_file *m)	\
 {									\
 	struct blk_mq_hw_ctx *hctx = data;				\
 	struct kyber_hctx_data *khd = hctx->sched_data;			\
-	wait_queue_t *wait = &khd->domain_wait[domain];			\
+	wait_queue_entry_t *wait = &khd->domain_wait[domain];		\
 									\
 	seq_printf(m, "%d\n", !list_empty_careful(&wait->task_list));	\
 	return 0;							\