From bd6737f1ae92e2f1c6e8362efe96dbe7f18fa07d Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 27 Jan 2017 01:00:47 -0700 Subject: blk-mq-sched: add flush insertion into blk_mq_sched_insert_request() Instead of letting the caller check this and handle the details of inserting a flush request, put the logic in the scheduler insertion function. This fixes direct flush insertion outside of the usual make_request_fn calls, like from dm via blk_insert_cloned_request(). Signed-off-by: Jens Axboe --- block/blk-mq-sched.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) (limited to 'block/blk-mq-sched.c') diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 4139b07ab33b..1112752f888d 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -335,6 +335,64 @@ void blk_mq_sched_restart_queues(struct blk_mq_hw_ctx *hctx) } } +/* + * Add flush/fua to the queue. If we fail getting a driver tag, then + * punt to the requeue list. Requeue will re-invoke us from a context + * that's safe to block from. + */ +static void blk_mq_sched_insert_flush(struct blk_mq_hw_ctx *hctx, + struct request *rq, bool can_block) +{ + if (blk_mq_get_driver_tag(rq, &hctx, can_block)) { + blk_insert_flush(rq); + blk_mq_run_hw_queue(hctx, true); + } else + blk_mq_add_to_requeue_list(rq, true, true); +} + +void blk_mq_sched_insert_request(struct request *rq, bool at_head, + bool run_queue, bool async, bool can_block) +{ + struct request_queue *q = rq->q; + struct elevator_queue *e = q->elevator; + struct blk_mq_ctx *ctx = rq->mq_ctx; + struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu); + + if (rq->tag == -1 && (rq->cmd_flags & (REQ_PREFLUSH | REQ_FUA))) { + blk_mq_sched_insert_flush(hctx, rq, can_block); + return; + } + + if (e && e->type->ops.mq.insert_requests) { + LIST_HEAD(list); + + list_add(&rq->queuelist, &list); + e->type->ops.mq.insert_requests(hctx, &list, at_head); + } else { + spin_lock(&ctx->lock); + __blk_mq_insert_request(hctx, rq, at_head); + spin_unlock(&ctx->lock); + } + + if (run_queue) + blk_mq_run_hw_queue(hctx, async); +} + +void blk_mq_sched_insert_requests(struct request_queue *q, + struct blk_mq_ctx *ctx, + struct list_head *list, bool run_queue_async) +{ + struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu); + struct elevator_queue *e = hctx->queue->elevator; + + if (e && e->type->ops.mq.insert_requests) + e->type->ops.mq.insert_requests(hctx, list, false); + else + blk_mq_insert_requests(hctx, ctx, list); + + blk_mq_run_hw_queue(hctx, run_queue_async); +} + static void blk_mq_sched_free_tags(struct blk_mq_tag_set *set, struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) -- cgit