diff options
-rw-r--r-- | block/mq-deadline.c | 45 |
1 files changed, 31 insertions, 14 deletions
diff --git a/block/mq-deadline.c b/block/mq-deadline.c index 44222d18f6d4..91b689261d30 100644 --- a/block/mq-deadline.c +++ b/block/mq-deadline.c @@ -74,8 +74,8 @@ struct dd_per_prio { struct list_head dispatch; struct rb_root sort_list[DD_DIR_COUNT]; struct list_head fifo_list[DD_DIR_COUNT]; - /* Next request in FIFO order. Read, write or both are NULL. */ - struct request *next_rq[DD_DIR_COUNT]; + /* Position of the most recently dispatched request. */ + sector_t latest_pos[DD_DIR_COUNT]; struct io_stats_per_prio stats; }; @@ -156,6 +156,25 @@ deadline_latter_request(struct request *rq) return NULL; } +/* Return the first request for which blk_rq_pos() >= pos. */ +static inline struct request *deadline_from_pos(struct dd_per_prio *per_prio, + enum dd_data_dir data_dir, sector_t pos) +{ + struct rb_node *node = per_prio->sort_list[data_dir].rb_node; + struct request *rq, *res = NULL; + + while (node) { + rq = rb_entry_rq(node); + if (blk_rq_pos(rq) >= pos) { + res = rq; + node = node->rb_left; + } else { + node = node->rb_right; + } + } + return res; +} + static void deadline_add_rq_rb(struct dd_per_prio *per_prio, struct request *rq) { @@ -167,11 +186,6 @@ deadline_add_rq_rb(struct dd_per_prio *per_prio, struct request *rq) static inline void deadline_del_rq_rb(struct dd_per_prio *per_prio, struct request *rq) { - const enum dd_data_dir data_dir = rq_data_dir(rq); - - if (per_prio->next_rq[data_dir] == rq) - per_prio->next_rq[data_dir] = deadline_latter_request(rq); - elv_rb_del(deadline_rb_root(per_prio, rq), rq); } @@ -251,10 +265,6 @@ static void deadline_move_request(struct deadline_data *dd, struct dd_per_prio *per_prio, struct request *rq) { - const enum dd_data_dir data_dir = rq_data_dir(rq); - - per_prio->next_rq[data_dir] = deadline_latter_request(rq); - /* * take it off the sort and fifo list */ @@ -363,7 +373,8 @@ deadline_next_request(struct deadline_data *dd, struct dd_per_prio *per_prio, struct request *rq; unsigned long flags; - rq = per_prio->next_rq[data_dir]; + rq = deadline_from_pos(per_prio, data_dir, + per_prio->latest_pos[data_dir]); if (!rq) return NULL; @@ -426,6 +437,7 @@ static struct request *__dd_dispatch_request(struct deadline_data *dd, if (started_after(dd, rq, latest_start)) return NULL; list_del_init(&rq->queuelist); + data_dir = rq_data_dir(rq); goto done; } @@ -433,9 +445,11 @@ static struct request *__dd_dispatch_request(struct deadline_data *dd, * batches are currently reads XOR writes */ rq = deadline_next_request(dd, per_prio, dd->last_dir); - if (rq && dd->batching < dd->fifo_batch) + if (rq && dd->batching < dd->fifo_batch) { /* we have a next request and are still entitled to batch */ + data_dir = rq_data_dir(rq); goto dispatch_request; + } /* * at this point we are not running a batch. select the appropriate @@ -513,6 +527,7 @@ dispatch_request: done: ioprio_class = dd_rq_ioclass(rq); prio = ioprio_class_to_prio[ioprio_class]; + dd->per_prio[prio].latest_pos[data_dir] = blk_rq_pos(rq); dd->per_prio[prio].stats.dispatched++; /* * If the request needs its target zone locked, do it. @@ -1026,8 +1041,10 @@ static int deadline_##name##_next_rq_show(void *data, \ struct request_queue *q = data; \ struct deadline_data *dd = q->elevator->elevator_data; \ struct dd_per_prio *per_prio = &dd->per_prio[prio]; \ - struct request *rq = per_prio->next_rq[data_dir]; \ + struct request *rq; \ \ + rq = deadline_from_pos(per_prio, data_dir, \ + per_prio->latest_pos[data_dir]); \ if (rq) \ __blk_mq_debugfs_rq_show(m, rq); \ return 0; \ |