blk-mq-sched: Fix blk_mq_sched_alloc_tags() error handling

If the blk_mq_sched_alloc_tags() -> blk_mq_alloc_rqs() call fails, then we
call blk_mq_sched_free_tags() -> blk_mq_free_rqs().

It is incorrect to do so, as any rqs would have already been freed in the
blk_mq_alloc_rqs() call.

Fix by calling blk_mq_free_rq_map() only directly.

Fixes: 6917ff0b5b ("blk-mq-sched: refactor scheduler initialization")
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/1627378373-148090-1-git-send-email-john.garry@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
John Garry 2021-07-27 17:32:53 +08:00 committed by Jens Axboe
parent 3ce6e1f662
commit b93af3055d

View File

@ -515,17 +515,6 @@ void blk_mq_sched_insert_requests(struct blk_mq_hw_ctx *hctx,
percpu_ref_put(&q->q_usage_counter); percpu_ref_put(&q->q_usage_counter);
} }
static void blk_mq_sched_free_tags(struct blk_mq_tag_set *set,
struct blk_mq_hw_ctx *hctx,
unsigned int hctx_idx)
{
if (hctx->sched_tags) {
blk_mq_free_rqs(set, hctx->sched_tags, hctx_idx);
blk_mq_free_rq_map(hctx->sched_tags, set->flags);
hctx->sched_tags = NULL;
}
}
static int blk_mq_sched_alloc_tags(struct request_queue *q, static int blk_mq_sched_alloc_tags(struct request_queue *q,
struct blk_mq_hw_ctx *hctx, struct blk_mq_hw_ctx *hctx,
unsigned int hctx_idx) unsigned int hctx_idx)
@ -539,8 +528,10 @@ static int blk_mq_sched_alloc_tags(struct request_queue *q,
return -ENOMEM; return -ENOMEM;
ret = blk_mq_alloc_rqs(set, hctx->sched_tags, hctx_idx, q->nr_requests); ret = blk_mq_alloc_rqs(set, hctx->sched_tags, hctx_idx, q->nr_requests);
if (ret) if (ret) {
blk_mq_sched_free_tags(set, hctx, hctx_idx); blk_mq_free_rq_map(hctx->sched_tags, set->flags);
hctx->sched_tags = NULL;
}
return ret; return ret;
} }