Commit ed3896ac authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

block: add two helpers for registering/un-registering sched debugfs 



Add blk_mq_sched_reg_debugfs()/blk_mq_sched_unreg_debugfs() to clean up
sched init/exit code a bit.

Register & unregister debugfs for sched & sched_hctx order is changed a
bit, but it is safe because sched & sched_hctx is guaranteed to be ready
when exporting via debugfs.

Reviewed-by: default avatarYu Kuai <yukuai3@huawei.com>
Reviewed-by: default avatarNilay Shroff <nilay@linux.ibm.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-6-ming.lei@redhat.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 94209d27

block/blk-mq-sched.c

+30 −15
Original line number Diff line number Diff line
@@ -434,6 +434,30 @@ static int blk_mq_init_sched_shared_tags(struct request_queue *queue) 
	return 0;

}



static void blk_mq_sched_reg_debugfs(struct request_queue *q)

{

	struct blk_mq_hw_ctx *hctx;

	unsigned long i;



	mutex_lock(&q->debugfs_mutex);

	blk_mq_debugfs_register_sched(q);

	queue_for_each_hw_ctx(q, hctx, i)

		blk_mq_debugfs_register_sched_hctx(q, hctx);

	mutex_unlock(&q->debugfs_mutex);

}



static void blk_mq_sched_unreg_debugfs(struct request_queue *q)

{

	struct blk_mq_hw_ctx *hctx;

	unsigned long i;



	mutex_lock(&q->debugfs_mutex);

	queue_for_each_hw_ctx(q, hctx, i)

		blk_mq_debugfs_unregister_sched_hctx(hctx);

	blk_mq_debugfs_unregister_sched(q);

	mutex_unlock(&q->debugfs_mutex);

}



/* caller must have a reference to @e, will grab another one if successful */

int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e)

{
@@ -467,10 +491,6 @@ int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e) 
	if (ret)

		goto err_free_map_and_rqs;



	mutex_lock(&q->debugfs_mutex);

	blk_mq_debugfs_register_sched(q);

	mutex_unlock(&q->debugfs_mutex);



	queue_for_each_hw_ctx(q, hctx, i) {

		if (e->ops.init_hctx) {

			ret = e->ops.init_hctx(hctx, i);
@@ -482,11 +502,11 @@ int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e) 
				return ret;

			}

		}

		mutex_lock(&q->debugfs_mutex);

		blk_mq_debugfs_register_sched_hctx(q, hctx);

		mutex_unlock(&q->debugfs_mutex);

	}



	/* sched is initialized, it is ready to export it via debugfs */

	blk_mq_sched_reg_debugfs(q);



	return 0;



err_free_map_and_rqs:
@@ -524,11 +544,10 @@ void blk_mq_exit_sched(struct request_queue *q, struct elevator_queue *e) 
	unsigned long i;

	unsigned int flags = 0;



	queue_for_each_hw_ctx(q, hctx, i) {

		mutex_lock(&q->debugfs_mutex);

		blk_mq_debugfs_unregister_sched_hctx(hctx);

		mutex_unlock(&q->debugfs_mutex);

	/* unexport via debugfs before exiting sched */

	blk_mq_sched_unreg_debugfs(q);



	queue_for_each_hw_ctx(q, hctx, i) {

		if (e->type->ops.exit_hctx && hctx->sched_data) {

			e->type->ops.exit_hctx(hctx, i);

			hctx->sched_data = NULL;
@@ -536,10 +555,6 @@ void blk_mq_exit_sched(struct request_queue *q, struct elevator_queue *e) 
		flags = hctx->flags;

	}



	mutex_lock(&q->debugfs_mutex);

	blk_mq_debugfs_unregister_sched(q);

	mutex_unlock(&q->debugfs_mutex);



	if (e->type->ops.exit_sched)

		e->type->ops.exit_sched(e);

	blk_mq_sched_tags_teardown(q, flags);