blk-mq: rename blk_mq_hw_ctx->queue_rq_srcu to ->srcu

The RCU protection has been expanded to cover both queueing and
completion paths making ->queue_rq_srcu a misnomer.  Rename it to
->srcu as suggested by Bart.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Bart Van Assche <Bart.VanAssche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-mq.c

@@ -219,7 +219,7 @@ void blk_mq_quiesce_queue(struct request_queue *q)
 
 	queue_for_each_hw_ctx(q, hctx, i) {
 		if (hctx->flags & BLK_MQ_F_BLOCKING)
-			synchronize_srcu(hctx->queue_rq_srcu);
+			synchronize_srcu(hctx->srcu);
 		else
 			rcu = true;
 	}
@@ -564,7 +564,7 @@ static void hctx_unlock(struct blk_mq_hw_ctx *hctx, int srcu_idx)
 	if (!(hctx->flags & BLK_MQ_F_BLOCKING))
 		rcu_read_unlock();
 	else
-		srcu_read_unlock(hctx->queue_rq_srcu, srcu_idx);
+		srcu_read_unlock(hctx->srcu, srcu_idx);
 }
 
 static void hctx_lock(struct blk_mq_hw_ctx *hctx, int *srcu_idx)
@@ -572,7 +572,7 @@ static void hctx_lock(struct blk_mq_hw_ctx *hctx, int *srcu_idx)
 	if (!(hctx->flags & BLK_MQ_F_BLOCKING))
 		rcu_read_lock();
 	else
-		*srcu_idx = srcu_read_lock(hctx->queue_rq_srcu);
+		*srcu_idx = srcu_read_lock(hctx->srcu);
 }
 
 static void blk_mq_rq_update_aborted_gstate(struct request *rq, u64 gstate)
@@ -937,7 +937,7 @@ static void blk_mq_timeout_work(struct work_struct *work)
 			if (!(hctx->flags & BLK_MQ_F_BLOCKING))
 				has_rcu = true;
 			else
-				synchronize_srcu(hctx->queue_rq_srcu);
+				synchronize_srcu(hctx->srcu);
 
 			hctx->nr_expired = 0;
 		}
@@ -2101,7 +2101,7 @@ static void blk_mq_exit_hctx(struct request_queue *q,
 		set->ops->exit_hctx(hctx, hctx_idx);
 
 	if (hctx->flags & BLK_MQ_F_BLOCKING)
-		cleanup_srcu_struct(hctx->queue_rq_srcu);
+		cleanup_srcu_struct(hctx->srcu);
 
 	blk_mq_remove_cpuhp(hctx);
 	blk_free_flush_queue(hctx->fq);
@@ -2174,7 +2174,7 @@ static int blk_mq_init_hctx(struct request_queue *q,
 		goto free_fq;
 
 	if (hctx->flags & BLK_MQ_F_BLOCKING)
-		init_srcu_struct(hctx->queue_rq_srcu);
+		init_srcu_struct(hctx->srcu);
 
 	blk_mq_debugfs_register_hctx(q, hctx);
 
@@ -2463,7 +2463,7 @@ static int blk_mq_hw_ctx_size(struct blk_mq_tag_set *tag_set)
 {
 	int hw_ctx_size = sizeof(struct blk_mq_hw_ctx);
 
-	BUILD_BUG_ON(ALIGN(offsetof(struct blk_mq_hw_ctx, queue_rq_srcu),
+	BUILD_BUG_ON(ALIGN(offsetof(struct blk_mq_hw_ctx, srcu),
 			   __alignof__(struct blk_mq_hw_ctx)) !=
 		     sizeof(struct blk_mq_hw_ctx));
 

include/linux/blk-mq.h

@@ -66,7 +66,7 @@ struct blk_mq_hw_ctx {
 #endif
 
 	/* Must be the last member - see also blk_mq_hw_ctx_size(). */
-	struct srcu_struct	queue_rq_srcu[0];
+	struct srcu_struct	srcu[0];
 };
 
 struct blk_mq_tag_set {