block: remove unused ->busy part of the block queue tag map

It's not used for anything. On top of that, it's racy and can thus
trigger a faulty BUG_ON() in __blk_free_tags() on queue exit.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Matthew Wilcox 2008-08-26 09:02:28 +02:00 committed by Jens Axboe
parent aefcc28a3a
commit 0e3eb45e4f

View file

@ -38,7 +38,8 @@ static int __blk_free_tags(struct blk_queue_tag *bqt)
retval = atomic_dec_and_test(&bqt->refcnt);
if (retval) {
BUG_ON(bqt->busy);
BUG_ON(find_first_bit(bqt->tag_map, bqt->max_depth) <
bqt->max_depth);
kfree(bqt->tag_index);
bqt->tag_index = NULL;
@ -147,7 +148,6 @@ static struct blk_queue_tag *__blk_queue_init_tags(struct request_queue *q,
if (init_tag_map(q, tags, depth))
goto fail;
tags->busy = 0;
atomic_set(&tags->refcnt, 1);
return tags;
fail:
@ -313,7 +313,6 @@ void blk_queue_end_tag(struct request_queue *q, struct request *rq)
* unlock memory barrier semantics.
*/
clear_bit_unlock(tag, bqt->tag_map);
bqt->busy--;
}
EXPORT_SYMBOL(blk_queue_end_tag);
@ -368,7 +367,6 @@ int blk_queue_start_tag(struct request_queue *q, struct request *rq)
bqt->tag_index[tag] = rq;
blkdev_dequeue_request(rq);
list_add(&rq->queuelist, &q->tag_busy_list);
bqt->busy++;
return 0;
}
EXPORT_SYMBOL(blk_queue_start_tag);