diff options
| author | Damien Le Moal <damien.lemoal@wdc.com> | 2019-10-09 07:39:54 +0900 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2019-10-14 13:54:09 -0600 |
| commit | 7a7c5e715e722c86d602c56a09e77f000364e263 (patch) | |
| tree | 4b074360edf8311721c51b4e3d3fd0ac3e8e0f21 | |
| parent | 7adf4eaf60f3d8c3584bed51fe7066d4dfc2cbe1 (diff) | |
block: Fix elv_support_iosched()
A BIO based request queue does not have a tag_set, which prevent testing
for the flag BLK_MQ_F_NO_SCHED indicating that the queue does not
require an elevator. This leads to an incorrect initialization of a
default elevator in some cases such as BIO based null_blk
(queue_mode == BIO) with zoned mode enabled as the default elevator in
this case is mq-deadline instead of "none".
Fix this by testing for a NULL queue mq_ops field which indicates that
the queue is BIO based and should not have an elevator.
Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/elevator.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/block/elevator.c b/block/elevator.c index 5437059c9261..076ba7308e65 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -616,7 +616,8 @@ out: static inline bool elv_support_iosched(struct request_queue *q) { - if (q->tag_set && (q->tag_set->flags & BLK_MQ_F_NO_SCHED)) + if (!q->mq_ops || + (q->tag_set && (q->tag_set->flags & BLK_MQ_F_NO_SCHED))) return false; return true; } |