From be4c427809b0a746aff54dbb8ef663f0184291d0 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Fri, 19 May 2023 06:40:47 +0200 Subject: blk-mq: use the I/O scheduler for writes from the flush state machine Send write requests issued by the flush state machine through the normal I/O submission path including the I/O scheduler (if present) so that I/O scheduler policies are applied to writes with the FUA flag set. Separate the I/O scheduler members from the flush members in struct request since now a request may pass through both an I/O scheduler and the flush machinery. Note that the actual flush requests, which have no bio attached to the request still bypass the I/O schedulers. Signed-off-by: Bart Van Assche [hch: rebased] Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Link: https://lore.kernel.org/r/20230519044050.107790-5-hch@lst.de Signed-off-by: Jens Axboe --- block/blk-mq.c | 4 ++-- include/linux/blk-mq.h | 27 +++++++++++---------------- 2 files changed, 13 insertions(+), 18 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index c0b394096b6b..aac67bc3d368 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -458,7 +458,7 @@ static struct request *__blk_mq_alloc_requests(struct blk_mq_alloc_data *data) * Flush/passthrough requests are special and go directly to the * dispatch list. */ - if (!op_is_flush(data->cmd_flags) && + if ((data->cmd_flags & REQ_OP_MASK) != REQ_OP_FLUSH && !blk_op_is_passthrough(data->cmd_flags)) { struct elevator_mq_ops *ops = &q->elevator->type->ops; @@ -2497,7 +2497,7 @@ static void blk_mq_insert_request(struct request *rq, blk_insert_t flags) * dispatch it given we prioritize requests in hctx->dispatch. */ blk_mq_request_bypass_insert(rq, flags); - } else if (rq->rq_flags & RQF_FLUSH_SEQ) { + } else if (req_op(rq) == REQ_OP_FLUSH) { /* * Firstly normal IO request is inserted to scheduler queue or * sw queue, meantime we add flush request to dispatch queue( diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 49d14b1acfa5..935201c89743 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -169,25 +169,20 @@ struct request { void *completion_data; }; - /* * Three pointers are available for the IO schedulers, if they need - * more they have to dynamically allocate it. Flush requests are - * never put on the IO scheduler. So let the flush fields share - * space with the elevator data. + * more they have to dynamically allocate it. */ - union { - struct { - struct io_cq *icq; - void *priv[2]; - } elv; - - struct { - unsigned int seq; - struct list_head list; - rq_end_io_fn *saved_end_io; - } flush; - }; + struct { + struct io_cq *icq; + void *priv[2]; + } elv; + + struct { + unsigned int seq; + struct list_head list; + rq_end_io_fn *saved_end_io; + } flush; union { struct __call_single_data csd; -- cgit v1.2.3