diff options
Diffstat (limited to 'block/elevator.c')
-rw-r--r-- | block/elevator.c | 39 |
1 files changed, 30 insertions, 9 deletions
diff --git a/block/elevator.c b/block/elevator.c index 9edba1b..d0acb31 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -100,14 +100,14 @@ static void elevator_put(struct elevator_type *e) module_put(e->elevator_owner); } -static struct elevator_type *elevator_get(const char *name) +static struct elevator_type *elevator_get(const char *name, bool try_loading) { struct elevator_type *e; spin_lock(&elv_list_lock); e = elevator_find(name); - if (!e) { + if (!e && try_loading) { spin_unlock(&elv_list_lock); request_module("%s-iosched", name); spin_lock(&elv_list_lock); @@ -136,6 +136,22 @@ static int __init elevator_setup(char *str) __setup("elevator=", elevator_setup); +/* called during boot to load the elevator chosen by the elevator param */ +void __init load_default_elevator_module(void) +{ + struct elevator_type *e; + + if (!chosen_elevator[0]) + return; + + spin_lock(&elv_list_lock); + e = elevator_find(chosen_elevator); + spin_unlock(&elv_list_lock); + + if (!e) + request_module("%s-iosched", chosen_elevator); +} + static struct kobj_type elv_ktype; static struct elevator_queue *elevator_alloc(struct request_queue *q, @@ -191,25 +207,30 @@ int elevator_init(struct request_queue *q, char *name) q->boundary_rq = NULL; if (name) { - e = elevator_get(name); + e = elevator_get(name, true); if (!e) return -EINVAL; } + /* + * Use the default elevator specified by config boot param or + * config option. Don't try to load modules as we could be running + * off async and request_module() isn't allowed from async. + */ if (!e && *chosen_elevator) { - e = elevator_get(chosen_elevator); + e = elevator_get(chosen_elevator, false); if (!e) printk(KERN_ERR "I/O scheduler %s not found\n", chosen_elevator); } if (!e) { - e = elevator_get(CONFIG_DEFAULT_IOSCHED); + e = elevator_get(CONFIG_DEFAULT_IOSCHED, false); if (!e) { printk(KERN_ERR "Default I/O scheduler not found. " \ "Using noop.\n"); - e = elevator_get("noop"); + e = elevator_get("noop", false); } } @@ -267,10 +288,10 @@ static struct request *elv_rqhash_find(struct request_queue *q, sector_t offset) { struct elevator_queue *e = q->elevator; struct hlist_head *hash_list = &e->hash[ELV_HASH_FN(offset)]; - struct hlist_node *entry, *next; + struct hlist_node *next; struct request *rq; - hlist_for_each_entry_safe(rq, entry, next, hash_list, hash) { + hlist_for_each_entry_safe(rq, next, hash_list, hash) { BUG_ON(!ELV_ON_HASH(rq)); if (unlikely(!rq_mergeable(rq))) { @@ -951,7 +972,7 @@ int elevator_change(struct request_queue *q, const char *name) return -ENXIO; strlcpy(elevator_name, name, sizeof(elevator_name)); - e = elevator_get(strstrip(elevator_name)); + e = elevator_get(strstrip(elevator_name), true); if (!e) { printk(KERN_ERR "elevator: type %s not found\n", elevator_name); return -EINVAL; |