block: make blk_init_free_list and elevator_init idempotent

blk_init_allocated_queue_node may fail and the caller _could_ retry.
Accommodate the unlikely event that blk_init_allocated_queue_node is
called on an already initialized (possibly partially) request_queue.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
This commit is contained in:
Mike Snitzer 2010-05-25 13:15:15 -04:00 committed by Jens Axboe
parent c86d1b8ae6
commit 1abec4fdbb
2 changed files with 7 additions and 2 deletions

View File

@ -467,6 +467,9 @@ static int blk_init_free_list(struct request_queue *q)
{
struct request_list *rl = &q->rq;
if (unlikely(rl->rq_pool))
return 0;
rl->count[BLK_RW_SYNC] = rl->count[BLK_RW_ASYNC] = 0;
rl->starved[BLK_RW_SYNC] = rl->starved[BLK_RW_ASYNC] = 0;
rl->elvpriv = 0;

View File

@ -242,9 +242,11 @@ int elevator_init(struct request_queue *q, char *name)
{
struct elevator_type *e = NULL;
struct elevator_queue *eq;
int ret = 0;
void *data;
if (unlikely(q->elevator))
return 0;
INIT_LIST_HEAD(&q->queue_head);
q->last_merge = NULL;
q->end_sector = 0;
@ -284,7 +286,7 @@ int elevator_init(struct request_queue *q, char *name)
}
elevator_attach(q, eq, data);
return ret;
return 0;
}
EXPORT_SYMBOL(elevator_init);