diff options
Diffstat (limited to 'block/elevator.c')
| -rw-r--r-- | block/elevator.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/block/elevator.c b/block/elevator.c index 86836dd..261ffaa 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -944,10 +944,14 @@ void elv_completed_request(struct request_queue *q, struct request *rq) * drained for flush sequence. */ if (unlikely(q->ordseq)) { - struct request *first_rq = list_entry_rq(q->queue_head.next); - if (q->in_flight == 0 && + struct request *next = NULL; + + if (!list_empty(&q->queue_head)) + next = list_entry_rq(q->queue_head.next); + + if (!q->in_flight && blk_ordered_cur_seq(q) == QUEUE_ORDSEQ_DRAIN && - blk_ordered_req_seq(first_rq) > QUEUE_ORDSEQ_DRAIN) { + (!next || blk_ordered_req_seq(next) > QUEUE_ORDSEQ_DRAIN)) { blk_ordered_complete_seq(q, QUEUE_ORDSEQ_DRAIN, 0); blk_start_queueing(q); } |
