From 8b4922d3173d2eee7b43be8e5caec3ab7d30feff Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 24 Feb 2014 16:39:52 +0100 Subject: [PATCH] block: Stop abusing csd.list for fifo_time Block layer currently abuses rq->csd.list.next for storing fifo_time. That is a terrible hack and completely unnecessary as well. Union achieves the same space saving in a cleaner way. Signed-off-by: Jan Kara Cc: Andrew Morton Cc: Christoph Hellwig Cc: Ingo Molnar Cc: Jens Axboe Signed-off-by: Frederic Weisbecker Signed-off-by: Jens Axboe --- block/cfq-iosched.c | 8 ++++---- block/deadline-iosched.c | 8 ++++---- include/linux/blkdev.h | 1 + include/linux/elevator.h | 6 ------ 4 files changed, 9 insertions(+), 14 deletions(-) diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 744833b630c6..5873e4ada9eb 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -2367,10 +2367,10 @@ cfq_merged_requests(struct request_queue *q, struct request *rq, * reposition in fifo if next is older than rq */ if (!list_empty(&rq->queuelist) && !list_empty(&next->queuelist) && - time_before(rq_fifo_time(next), rq_fifo_time(rq)) && + time_before(next->fifo_time, rq->fifo_time) && cfqq == RQ_CFQQ(next)) { list_move(&rq->queuelist, &next->queuelist); - rq_set_fifo_time(rq, rq_fifo_time(next)); + rq->fifo_time = next->fifo_time; } if (cfqq->next_rq == next) @@ -2814,7 +2814,7 @@ static struct request *cfq_check_fifo(struct cfq_queue *cfqq) return NULL; rq = rq_entry_fifo(cfqq->fifo.next); - if (time_before(jiffies, rq_fifo_time(rq))) + if (time_before(jiffies, rq->fifo_time)) rq = NULL; cfq_log_cfqq(cfqq->cfqd, cfqq, "fifo=%p", rq); @@ -3927,7 +3927,7 @@ static void cfq_insert_request(struct request_queue *q, struct request *rq) cfq_log_cfqq(cfqd, cfqq, "insert_request"); cfq_init_prio_data(cfqq, RQ_CIC(rq)); - rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]); + rq->fifo_time = jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]; list_add_tail(&rq->queuelist, &cfqq->fifo); cfq_add_rq_rb(rq); cfqg_stats_update_io_add(RQ_CFQG(rq), cfqd->serving_group, diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c index 9ef66406c625..a753df2b3fc2 100644 --- a/block/deadline-iosched.c +++ b/block/deadline-iosched.c @@ -106,7 +106,7 @@ deadline_add_request(struct request_queue *q, struct request *rq) /* * set expire time and add to fifo list */ - rq_set_fifo_time(rq, jiffies + dd->fifo_expire[data_dir]); + rq->fifo_time = jiffies + dd->fifo_expire[data_dir]; list_add_tail(&rq->queuelist, &dd->fifo_list[data_dir]); } @@ -174,9 +174,9 @@ deadline_merged_requests(struct request_queue *q, struct request *req, * and move into next position (next will be deleted) in fifo */ if (!list_empty(&req->queuelist) && !list_empty(&next->queuelist)) { - if (time_before(rq_fifo_time(next), rq_fifo_time(req))) { + if (time_before(next->fifo_time, req->fifo_time)) { list_move(&req->queuelist, &next->queuelist); - rq_set_fifo_time(req, rq_fifo_time(next)); + req->fifo_time = next->fifo_time; } } @@ -230,7 +230,7 @@ static inline int deadline_check_fifo(struct deadline_data *dd, int ddir) /* * rq is expired! */ - if (time_after_eq(jiffies, rq_fifo_time(rq))) + if (time_after_eq(jiffies, rq->fifo_time)) return 1; return 0; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 4afa4f8f6090..1e1fa3f93d5f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -99,6 +99,7 @@ struct request { union { struct call_single_data csd; struct work_struct mq_flush_work; + unsigned long fifo_time; }; struct request_queue *q; diff --git a/include/linux/elevator.h b/include/linux/elevator.h index 306dd8cd0b6f..0bdfd46f4735 100644 --- a/include/linux/elevator.h +++ b/include/linux/elevator.h @@ -202,12 +202,6 @@ enum { #define rq_end_sector(rq) (blk_rq_pos(rq) + blk_rq_sectors(rq)) #define rb_entry_rq(node) rb_entry((node), struct request, rb_node) -/* - * Hack to reuse the csd.list list_head as the fifo time holder while - * the request is in the io scheduler. Saves an unsigned long in rq. - */ -#define rq_fifo_time(rq) ((unsigned long) (rq)->csd.list.next) -#define rq_set_fifo_time(rq,exp) ((rq)->csd.list.next = (void *) (exp)) #define rq_entry_fifo(ptr) list_entry((ptr), struct request, queuelist) #define rq_fifo_clear(rq) do { \ list_del_init(&(rq)->queuelist); \ -- 2.39.2