diff options
| -rw-r--r-- | block/mq-deadline.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/block/mq-deadline.c b/block/mq-deadline.c index f92224ff0256..44da481c3fea 100644 --- a/block/mq-deadline.c +++ b/block/mq-deadline.c @@ -67,6 +67,7 @@ struct deadline_data { int fifo_batch; int writes_starved; int front_merges; + u32 async_depth; spinlock_t lock; spinlock_t zone_lock; @@ -397,6 +398,44 @@ static struct request *dd_dispatch_request(struct blk_mq_hw_ctx *hctx) return rq; } +/* + * Called by __blk_mq_alloc_request(). The shallow_depth value set by this + * function is used by __blk_mq_get_tag(). + */ +static void dd_limit_depth(unsigned int op, struct blk_mq_alloc_data *data) +{ + struct deadline_data *dd = data->q->elevator->elevator_data; + + /* Do not throttle synchronous reads. */ + if (op_is_sync(op) && !op_is_write(op)) + return; + + /* + * Throttle asynchronous requests and writes such that these requests + * do not block the allocation of synchronous requests. + */ + data->shallow_depth = dd->async_depth; +} + +/* Called by blk_mq_update_nr_requests(). */ +static void dd_depth_updated(struct blk_mq_hw_ctx *hctx) +{ + struct request_queue *q = hctx->queue; + struct deadline_data *dd = q->elevator->elevator_data; + struct blk_mq_tags *tags = hctx->sched_tags; + + dd->async_depth = max(1UL, 3 * q->nr_requests / 4); + + sbitmap_queue_min_shallow_depth(tags->bitmap_tags, dd->async_depth); +} + +/* Called by blk_mq_init_hctx() and blk_mq_init_sched(). */ +static int dd_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) +{ + dd_depth_updated(hctx); + return 0; +} + static void dd_exit_sched(struct elevator_queue *e) { struct deadline_data *dd = e->elevator_data; @@ -617,6 +656,7 @@ SHOW_JIFFIES(deadline_read_expire_show, dd->fifo_expire[DD_READ]); SHOW_JIFFIES(deadline_write_expire_show, dd->fifo_expire[DD_WRITE]); SHOW_INT(deadline_writes_starved_show, dd->writes_starved); SHOW_INT(deadline_front_merges_show, dd->front_merges); +SHOW_INT(deadline_async_depth_show, dd->front_merges); SHOW_INT(deadline_fifo_batch_show, dd->fifo_batch); #undef SHOW_INT #undef SHOW_JIFFIES @@ -645,6 +685,7 @@ STORE_JIFFIES(deadline_read_expire_store, &dd->fifo_expire[DD_READ], 0, INT_MAX) STORE_JIFFIES(deadline_write_expire_store, &dd->fifo_expire[DD_WRITE], 0, INT_MAX); STORE_INT(deadline_writes_starved_store, &dd->writes_starved, INT_MIN, INT_MAX); STORE_INT(deadline_front_merges_store, &dd->front_merges, 0, 1); +STORE_INT(deadline_async_depth_store, &dd->front_merges, 1, INT_MAX); STORE_INT(deadline_fifo_batch_store, &dd->fifo_batch, 0, INT_MAX); #undef STORE_FUNCTION #undef STORE_INT @@ -658,6 +699,7 @@ static struct elv_fs_entry deadline_attrs[] = { DD_ATTR(write_expire), DD_ATTR(writes_starved), DD_ATTR(front_merges), + DD_ATTR(async_depth), DD_ATTR(fifo_batch), __ATTR_NULL }; @@ -733,6 +775,15 @@ static int deadline_starved_show(void *data, struct seq_file *m) return 0; } +static int dd_async_depth_show(void *data, struct seq_file *m) +{ + struct request_queue *q = data; + struct deadline_data *dd = q->elevator->elevator_data; + + seq_printf(m, "%u\n", dd->async_depth); + return 0; +} + static void *deadline_dispatch_start(struct seq_file *m, loff_t *pos) __acquires(&dd->lock) { @@ -775,6 +826,7 @@ static const struct blk_mq_debugfs_attr deadline_queue_debugfs_attrs[] = { DEADLINE_QUEUE_DDIR_ATTRS(write), {"batching", 0400, deadline_batching_show}, {"starved", 0400, deadline_starved_show}, + {"async_depth", 0400, dd_async_depth_show}, {"dispatch", 0400, .seq_ops = &deadline_dispatch_seq_ops}, {}, }; @@ -783,6 +835,8 @@ static const struct blk_mq_debugfs_attr deadline_queue_debugfs_attrs[] = { static struct elevator_type mq_deadline = { .ops = { + .depth_updated = dd_depth_updated, + .limit_depth = dd_limit_depth, .insert_requests = dd_insert_requests, .dispatch_request = dd_dispatch_request, .prepare_request = dd_prepare_request, @@ -796,6 +850,7 @@ static struct elevator_type mq_deadline = { .has_work = dd_has_work, .init_sched = dd_init_sched, .exit_sched = dd_exit_sched, + .init_hctx = dd_init_hctx, }, #ifdef CONFIG_BLK_DEBUG_FS |