diff options
Diffstat (limited to 'block/blk-flush.c')
| -rw-r--r-- | block/blk-flush.c | 26 |
1 files changed, 16 insertions, 10 deletions
diff --git a/block/blk-flush.c b/block/blk-flush.c index 20b7c7a02f1c..0d5a9c1da1fc 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -74,6 +74,7 @@ #include "blk.h" #include "blk-mq.h" #include "blk-mq-tag.h" +#include "blk-mq-sched.h" /* FLUSH/FUA sequences */ enum { @@ -296,8 +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; @@ -326,7 +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; @@ -391,9 +397,10 @@ static void mq_flush_data_end_io(struct request *rq, int error) * the comment in flush_end_io(). */ spin_lock_irqsave(&fq->mq_flush_lock, flags); - if (blk_flush_complete_seq(rq, fq, REQ_FSEQ_DATA, error)) - blk_mq_run_hw_queue(hctx, true); + blk_flush_complete_seq(rq, fq, REQ_FSEQ_DATA, error); spin_unlock_irqrestore(&fq->mq_flush_lock, flags); + + blk_mq_run_hw_queue(hctx, true); } /** @@ -453,9 +460,9 @@ void blk_insert_flush(struct request *rq) */ if ((policy & REQ_FSEQ_DATA) && !(policy & (REQ_FSEQ_PREFLUSH | REQ_FSEQ_POSTFLUSH))) { - if (q->mq_ops) { - blk_mq_insert_request(rq, false, true, false); - } else + if (q->mq_ops) + blk_mq_sched_insert_request(rq, false, true, false, false); + else list_add_tail(&rq->queuelist, &q->queue_head); return; } @@ -545,11 +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; |