diff options
| -rw-r--r-- | block/blk-mq.c | 2 | ||||
| -rw-r--r-- | block/blk.h | 1 | ||||
| -rw-r--r-- | block/elevator.c | 77 |
3 files changed, 48 insertions, 32 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index 858d6edff4d3..6332940ca118 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2573,7 +2573,7 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, if (!(set->flags & BLK_MQ_F_NO_SCHED)) { int ret; - ret = elevator_init(q); + ret = elevator_init_mq(q); if (ret) return ERR_PTR(ret); } diff --git a/block/blk.h b/block/blk.h index ab5ec2dadc7b..8d23aea96ce9 100644 --- a/block/blk.h +++ b/block/blk.h @@ -232,6 +232,7 @@ static inline void elv_deactivate_rq(struct request_queue *q, struct request *rq } int elevator_init(struct request_queue *); +int elevator_init_mq(struct request_queue *q); void elevator_exit(struct request_queue *, struct elevator_queue *); int elv_register_queue(struct request_queue *q); void elv_unregister_queue(struct request_queue *q); diff --git a/block/elevator.c b/block/elevator.c index d6480e70816e..fa828b5bfd4b 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -199,6 +199,11 @@ static void elevator_release(struct kobject *kobj) kfree(e); } +/* + * Use the default elevator specified by config boot param for non-mq devices, + * or by config option. Don't try to load modules as we could be running off + * async and request_module() isn't allowed from async. + */ int elevator_init(struct request_queue *q) { struct elevator_type *e = NULL; @@ -212,46 +217,22 @@ int elevator_init(struct request_queue *q) if (unlikely(q->elevator)) goto out_unlock; - /* - * Use the default elevator specified by config boot param for - * non-mq devices, or by config option. Don't try to load modules - * as we could be running off async and request_module() isn't - * allowed from async. - */ - if (!q->mq_ops && *chosen_elevator) { + if (*chosen_elevator) { e = elevator_get(q, chosen_elevator, false); if (!e) printk(KERN_ERR "I/O scheduler %s not found\n", chosen_elevator); } + if (!e) + e = elevator_get(q, CONFIG_DEFAULT_IOSCHED, false); if (!e) { - /* - * For blk-mq devices, we default to using mq-deadline, - * if available, for single queue devices. If deadline - * isn't available OR we have multiple queues, default - * to "none". - */ - if (q->mq_ops) { - if (q->nr_hw_queues == 1) - e = elevator_get(q, "mq-deadline", false); - if (!e) - goto out_unlock; - } else - e = elevator_get(q, CONFIG_DEFAULT_IOSCHED, false); - - if (!e) { - printk(KERN_ERR - "Default I/O scheduler not found. " \ - "Using noop.\n"); - e = elevator_get(q, "noop", false); - } + printk(KERN_ERR + "Default I/O scheduler not found. Using noop.\n"); + e = elevator_get(q, "noop", false); } - if (e->uses_mq) - err = blk_mq_init_sched(q, e); - else - err = e->ops.sq.elevator_init_fn(q, e); + err = e->ops.sq.elevator_init_fn(q, e); if (err) elevator_put(e); out_unlock: @@ -993,6 +974,40 @@ out: } /* + * For blk-mq devices, we default to using mq-deadline, if available, for single + * queue devices. If deadline isn't available OR we have multiple queues, + * default to "none". + */ +int elevator_init_mq(struct request_queue *q) +{ + struct elevator_type *e; + int err = 0; + + if (q->nr_hw_queues != 1) + return 0; + + /* + * q->sysfs_lock must be held to provide mutual exclusion between + * elevator_switch() and here. + */ + mutex_lock(&q->sysfs_lock); + if (unlikely(q->elevator)) + goto out_unlock; + + e = elevator_get(q, "mq-deadline", false); + if (!e) + goto out_unlock; + + err = blk_mq_init_sched(q, e); + if (err) + elevator_put(e); +out_unlock: + mutex_unlock(&q->sysfs_lock); + return err; +} + + +/* * switch to new_e io scheduler. be careful not to introduce deadlocks - * we don't free the old io scheduler, before we have allocated what we * need for the new one. this way we have a chance of going back to the old |