block/mq-deadline: Set the fifo_time member also if inserting at head

Before commit 322cff70 the fifo_time member of requests on a dispatch
list was not used. Commit 322cff70 introduces code that reads the
fifo_time member of requests on dispatch lists. Hence this patch that sets
the fifo_time member when adding a request to a dispatch list.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Fixes: 322cff70 ("block/mq-deadline: Prioritize high-priority requests")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220513171307.32564-1-bvanassche@acm.orgSigned-off-by: Jens Axboe <axboe@kernel.dk>

block/mq-deadline.c

@@ -742,6 +742,7 @@ static void dd_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
 
 	if (at_head) {
 		list_add(&rq->queuelist, &per_prio->dispatch);
+		rq->fifo_time = jiffies;
 	} else {
 		deadline_add_rq_rb(per_prio, rq);