dm thin: simplify pool_is_congested

The pool is congested if the pool is in PM_OUT_OF_DATA_SPACE mode.  This
is more explicit/clear/efficient than inferring whether or not the pool
is congested by checking if retry_on_resume_list is empty.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
This commit is contained in:
Mike Snitzer 2014-03-20 08:36:47 -04:00
parent fe76cd88e6
commit 760fe67e53
1 changed files with 5 additions and 11 deletions

View File

@ -1757,20 +1757,14 @@ static int thin_bio_map(struct dm_target *ti, struct bio *bio)
static int pool_is_congested(struct dm_target_callbacks *cb, int bdi_bits)
{
int r;
unsigned long flags;
struct pool_c *pt = container_of(cb, struct pool_c, callbacks);
struct request_queue *q;
spin_lock_irqsave(&pt->pool->lock, flags);
r = !bio_list_empty(&pt->pool->retry_on_resume_list);
spin_unlock_irqrestore(&pt->pool->lock, flags);
if (get_pool_mode(pt->pool) == PM_OUT_OF_DATA_SPACE)
return 1;
if (!r) {
struct request_queue *q = bdev_get_queue(pt->data_dev->bdev);
r = bdi_congested(&q->backing_dev_info, bdi_bits);
}
return r;
q = bdev_get_queue(pt->data_dev->bdev);
return bdi_congested(&q->backing_dev_info, bdi_bits);
}
static void __requeue_bios(struct pool *pool)