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blk-mq: improve the blk_mq_init_allocated_queue interface

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Don't return the passed in request_queue but a normal error code, and
drop the elevator_init argument in favor of just calling elevator_init_mq
directly from dm-rq.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210602065345.355274-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2021-06-02 09:53:17 +03:00 committed by Jens Axboe
parent cdb14e0f77
commit 26a9750aa8
6 changed files with 21 additions and 33 deletions
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36
block/blk-mq.c
View file

@ -3115,21 +3115,18 @@ void blk_mq_release(struct request_queue *q)
struct request_queue *blk_mq_init_queue_data(struct blk_mq_tag_set *set,
void *queuedata)
{
struct request_queue *uninit_q, *q;
struct request_queue *q;
int ret;
uninit_q = blk_alloc_queue(set->numa_node);
if (!uninit_q)
q = blk_alloc_queue(set->numa_node);
if (!q)
return ERR_PTR(-ENOMEM);
uninit_q->queuedata = queuedata;
/*
* Initialize the queue without an elevator. device_add_disk() will do
* the initialization.
*/
q = blk_mq_init_allocated_queue(set, uninit_q, false);
if (IS_ERR(q))
blk_cleanup_queue(uninit_q);
q->queuedata = queuedata;
ret = blk_mq_init_allocated_queue(set, q);
if (ret) {
blk_cleanup_queue(q);
return ERR_PTR(ret);
}
return q;
}
EXPORT_SYMBOL_GPL(blk_mq_init_queue_data);
@ -3273,9 +3270,8 @@ static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set,
mutex_unlock(&q->sysfs_lock);
}
struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
struct request_queue *q,
bool elevator_init)
int blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
struct request_queue *q)
{
/* mark the queue as mq asap */
q->mq_ops = set->ops;
@ -3325,11 +3321,7 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
blk_mq_init_cpu_queues(q, set->nr_hw_queues);
blk_mq_add_queue_tag_set(set, q);
blk_mq_map_swqueue(q);
if (elevator_init)
elevator_init_mq(q);
return q;
return 0;
err_hctxs:
kfree(q->queue_hw_ctx);
@ -3340,7 +3332,7 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
q->poll_cb = NULL;
err_exit:
q->mq_ops = NULL;
return ERR_PTR(-ENOMEM);
return -ENOMEM;
}
EXPORT_SYMBOL(blk_mq_init_allocated_queue);

1
block/blk.h
View file

@ -192,7 +192,6 @@ void blk_account_io_done(struct request *req, u64 now);
void blk_insert_flush(struct request *rq);
void elevator_init_mq(struct request_queue *q);
int elevator_switch_mq(struct request_queue *q,
struct elevator_type *new_e);
void __elevator_exit(struct request_queue *, struct elevator_queue *);

2
block/elevator.c
View file

@ -693,7 +693,7 @@ void elevator_init_mq(struct request_queue *q)
elevator_put(e);
}
}
EXPORT_SYMBOL_GPL(elevator_init_mq); /* only for dm-rq */
/*
* switch to new_e io scheduler. be careful not to introduce deadlocks -

9
drivers/md/dm-rq.c
View file

@ -530,7 +530,6 @@ static const struct blk_mq_ops dm_mq_ops = {
int dm_mq_init_request_queue(struct mapped_device *md, struct dm_table *t)
{
struct request_queue *q;
struct dm_target *immutable_tgt;
int err;
@ -557,12 +556,10 @@ int dm_mq_init_request_queue(struct mapped_device *md, struct dm_table *t)
if (err)
goto out_kfree_tag_set;
q = blk_mq_init_allocated_queue(md->tag_set, md->queue, true);
if (IS_ERR(q)) {
err = PTR_ERR(q);
err = blk_mq_init_allocated_queue(md->tag_set, md->queue);
if (err)
goto out_tag_set;
}
elevator_init_mq(md->queue);
return 0;
out_tag_set:

5
include/linux/blk-mq.h
View file

@ -429,9 +429,8 @@ enum {
struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *);
struct request_queue *blk_mq_init_queue_data(struct blk_mq_tag_set *set,
void *queuedata);
struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
struct request_queue *q,
bool elevator_init);
int blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
struct request_queue *q);
struct request_queue *blk_mq_init_sq_queue(struct blk_mq_tag_set *set,
const struct blk_mq_ops *ops,
unsigned int queue_depth,

1
include/linux/elevator.h
View file

@ -120,6 +120,7 @@ extern void elv_merged_request(struct request_queue *, struct request *,
extern bool elv_attempt_insert_merge(struct request_queue *, struct request *);
extern struct request *elv_former_request(struct request_queue *, struct request *);
extern struct request *elv_latter_request(struct request_queue *, struct request *);
void elevator_init_mq(struct request_queue *q);
/*
* io scheduler registration