[PATCH 1/4] block: move the call to blk_queue_enter_live out of blk_mq_get_request

[Christoph Hellwig <hch@xxxxxx>]

Move the blk_queue_enter_live calls into the callers, where they can
successively be cleaned up.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 block/blk-mq.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 9ee695bdf8739..9865a36e6a6e3 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -340,8 +340,6 @@ static struct request *blk_mq_get_request(struct request_queue *q,
 	bool clear_ctx_on_error = false;
 	u64 alloc_time_ns = 0;
 
-	blk_queue_enter_live(q);
-
 	/* alloc_time includes depth and tag waits */
 	if (blk_queue_rq_alloc_time(q))
 		alloc_time_ns = ktime_get_ns();
@@ -377,7 +375,6 @@ static struct request *blk_mq_get_request(struct request_queue *q,
 	if (tag == BLK_MQ_TAG_FAIL) {
 		if (clear_ctx_on_error)
 			data->ctx = NULL;
-		blk_queue_exit(q);
 		return NULL;
 	}
 
@@ -407,11 +404,14 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
 	if (ret)
 		return ERR_PTR(ret);
 
+	blk_queue_enter_live(q);
 	rq = blk_mq_get_request(q, NULL, &alloc_data);
 	blk_queue_exit(q);
 
-	if (!rq)
+	if (!rq) {
+		blk_queue_exit(q);
 		return ERR_PTR(-EWOULDBLOCK);
+	}
 
 	rq->__data_len = 0;
 	rq->__sector = (sector_t) -1;
@@ -456,11 +456,14 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
 	cpu = cpumask_first_and(alloc_data.hctx->cpumask, cpu_online_mask);
 	alloc_data.ctx = __blk_mq_get_ctx(q, cpu);
 
+	blk_queue_enter_live(q);
 	rq = blk_mq_get_request(q, NULL, &alloc_data);
 	blk_queue_exit(q);
 
-	if (!rq)
+	if (!rq) {
+		blk_queue_exit(q);
 		return ERR_PTR(-EWOULDBLOCK);
+	}
 
 	return rq;
 }
@@ -2038,8 +2041,10 @@ blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
 	rq_qos_throttle(q, bio);
 
 	data.cmd_flags = bio->bi_opf;
+	blk_queue_enter_live(q);
 	rq = blk_mq_get_request(q, bio, &data);
 	if (unlikely(!rq)) {
+		blk_queue_exit(q);
 		rq_qos_cleanup(q, bio);
 		if (bio->bi_opf & REQ_NOWAIT)
 			bio_wouldblock_error(bio);
-- 
2.26.2