diff options
Diffstat (limited to 'block/blk-flush.c')
| -rw-r--r-- | block/blk-flush.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/block/blk-flush.c b/block/blk-flush.c index 4427896641ac..0d5a9c1da1fc 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -297,8 +297,14 @@ static bool blk_kick_flush(struct request_queue *q, struct blk_flush_queue *fq) if (fq->flush_pending_idx != fq->flush_running_idx || list_empty(pending)) return false; - /* C2 and C3 */ + /* C2 and C3 + * + * For blk-mq + scheduling, we can risk having all driver tags + * assigned to empty flushes, and we deadlock if we are expecting + * other requests to make progress. Don't defer for that case. + */ if (!list_empty(&fq->flush_data_in_flight) && + !(q->mq_ops && q->elevator) && time_before(jiffies, fq->flush_pending_since + FLUSH_PENDING_TIMEOUT)) return false; @@ -327,7 +333,6 @@ static bool blk_kick_flush(struct request_queue *q, struct blk_flush_queue *fq) blk_mq_tag_set_rq(hctx, first_rq->tag, flush_rq); } - flush_rq->cmd_type = REQ_TYPE_FS; flush_rq->cmd_flags = REQ_OP_FLUSH | REQ_PREFLUSH; flush_rq->rq_flags |= RQF_FLUSH_SEQ; flush_rq->rq_disk = first_rq->rq_disk; @@ -547,11 +552,10 @@ struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q, if (!fq) goto fail; - if (q->mq_ops) { + if (q->mq_ops) spin_lock_init(&fq->mq_flush_lock); - rq_sz = round_up(rq_sz + cmd_size, cache_line_size()); - } + rq_sz = round_up(rq_sz + cmd_size, cache_line_size()); fq->flush_rq = kzalloc_node(rq_sz, GFP_KERNEL, node); if (!fq->flush_rq) goto fail_rq; |