From a036e698c231ba884daa37196be3ac6c6dce1d75 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Wed, 17 May 2023 10:42:29 -0700 Subject: block: mq-deadline: Fix handling of at-head zoned writes Before dispatching a zoned write from the FIFO list, check whether there are any zoned writes in the RB-tree with a lower LBA for the same zone. This patch ensures that zoned writes happen in order even if at_head is set for some writes for a zone and not for others. Reviewed-by: Christoph Hellwig Reviewed-by: Damien Le Moal Cc: Ming Lei Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20230517174230.897144-12-bvanassche@acm.org Signed-off-by: Jens Axboe --- block/mq-deadline.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'block/mq-deadline.c') diff --git a/block/mq-deadline.c b/block/mq-deadline.c index e90879869c90..6aa5daf7ae32 100644 --- a/block/mq-deadline.c +++ b/block/mq-deadline.c @@ -346,7 +346,7 @@ static struct request * deadline_fifo_request(struct deadline_data *dd, struct dd_per_prio *per_prio, enum dd_data_dir data_dir) { - struct request *rq; + struct request *rq, *rb_rq, *next; unsigned long flags; if (list_empty(&per_prio->fifo_list[data_dir])) @@ -364,7 +364,12 @@ deadline_fifo_request(struct deadline_data *dd, struct dd_per_prio *per_prio, * zones and these zones are unlocked. */ spin_lock_irqsave(&dd->zone_lock, flags); - list_for_each_entry(rq, &per_prio->fifo_list[DD_WRITE], queuelist) { + list_for_each_entry_safe(rq, next, &per_prio->fifo_list[DD_WRITE], + queuelist) { + /* Check whether a prior request exists for the same zone. */ + rb_rq = deadline_from_pos(per_prio, data_dir, blk_rq_pos(rq)); + if (rb_rq && blk_rq_pos(rb_rq) < blk_rq_pos(rq)) + rq = rb_rq; if (blk_req_can_dispatch_to_zone(rq) && (blk_queue_nonrot(rq->q) || !deadline_is_seq_write(dd, rq))) -- cgit v1.2.3