diff options
| -rw-r--r-- | drivers/md/dm.c | 24 |
1 files changed, 16 insertions, 8 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index dc25d8a07bc..c99e4728ff4 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -937,16 +937,24 @@ static void dm_unplug_all(struct request_queue *q) static int dm_any_congested(void *congested_data, int bdi_bits) { - int r; - struct mapped_device *md = (struct mapped_device *) congested_data; - struct dm_table *map = dm_get_table(md); + int r = bdi_bits; + struct mapped_device *md = congested_data; + struct dm_table *map; - if (!map || test_bit(DMF_BLOCK_IO, &md->flags)) - r = bdi_bits; - else - r = dm_table_any_congested(map, bdi_bits); + atomic_inc(&md->pending); + + if (!test_bit(DMF_BLOCK_IO, &md->flags)) { + map = dm_get_table(md); + if (map) { + r = dm_table_any_congested(map, bdi_bits); + dm_table_put(map); + } + } + + if (!atomic_dec_return(&md->pending)) + /* nudge anyone waiting on suspend queue */ + wake_up(&md->wait); - dm_table_put(map); return r; } |