diff options
| -rw-r--r-- | block/cfq-iosched.c | 48 | ||||
| -rw-r--r-- | block/deadline-iosched.c | 4 | ||||
| -rw-r--r-- | block/elevator.c | 37 | ||||
| -rw-r--r-- | block/noop-iosched.c | 4 | ||||
| -rw-r--r-- | include/linux/elevator.h | 11 |
5 files changed, 62 insertions, 42 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 048fa699adf9..06e59abcb57f 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -3914,34 +3914,6 @@ static void *cfq_init_queue(struct request_queue *q) return cfqd; } -static void cfq_slab_kill(void) -{ - /* - * Caller already ensured that pending RCU callbacks are completed, - * so we should have no busy allocations at this point. - */ - if (cfq_pool) - kmem_cache_destroy(cfq_pool); - if (cfq_icq_pool) - kmem_cache_destroy(cfq_icq_pool); -} - -static int __init cfq_slab_setup(void) -{ - cfq_pool = KMEM_CACHE(cfq_queue, 0); - if (!cfq_pool) - goto fail; - - cfq_icq_pool = KMEM_CACHE(cfq_io_cq, 0); - if (!cfq_icq_pool) - goto fail; - - return 0; -fail: - cfq_slab_kill(); - return -ENOMEM; -} - /* * sysfs parts below --> */ @@ -4053,8 +4025,10 @@ static struct elevator_type iosched_cfq = { .elevator_init_fn = cfq_init_queue, .elevator_exit_fn = cfq_exit_queue, }, + .icq_size = sizeof(struct cfq_io_cq), + .icq_align = __alignof__(struct cfq_io_cq), .elevator_attrs = cfq_attrs, - .elevator_name = "cfq", + .elevator_name = "cfq", .elevator_owner = THIS_MODULE, }; @@ -4072,6 +4046,8 @@ static struct blkio_policy_type blkio_policy_cfq; static int __init cfq_init(void) { + int ret; + /* * could be 0 on HZ < 1000 setups */ @@ -4086,10 +4062,17 @@ static int __init cfq_init(void) #else cfq_group_idle = 0; #endif - if (cfq_slab_setup()) + cfq_pool = KMEM_CACHE(cfq_queue, 0); + if (!cfq_pool) return -ENOMEM; - elv_register(&iosched_cfq); + ret = elv_register(&iosched_cfq); + if (ret) { + kmem_cache_destroy(cfq_pool); + return ret; + } + cfq_icq_pool = iosched_cfq.icq_cache; + blkio_policy_register(&blkio_policy_cfq); return 0; @@ -4099,8 +4082,7 @@ static void __exit cfq_exit(void) { blkio_policy_unregister(&blkio_policy_cfq); elv_unregister(&iosched_cfq); - rcu_barrier(); /* make sure all cic RCU frees are complete */ - cfq_slab_kill(); + kmem_cache_destroy(cfq_pool); } module_init(cfq_init); diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c index c644137d9cd6..7bf12d793fcd 100644 --- a/block/deadline-iosched.c +++ b/block/deadline-iosched.c @@ -448,9 +448,7 @@ static struct elevator_type iosched_deadline = { static int __init deadline_init(void) { - elv_register(&iosched_deadline); - - return 0; + return elv_register(&iosched_deadline); } static void __exit deadline_exit(void) diff --git a/block/elevator.c b/block/elevator.c index c5c6214829cb..cca049fb45c8 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -886,15 +886,36 @@ void elv_unregister_queue(struct request_queue *q) } EXPORT_SYMBOL(elv_unregister_queue); -void elv_register(struct elevator_type *e) +int elv_register(struct elevator_type *e) { char *def = ""; + /* create icq_cache if requested */ + if (e->icq_size) { + if (WARN_ON(e->icq_size < sizeof(struct io_cq)) || + WARN_ON(e->icq_align < __alignof__(struct io_cq))) + return -EINVAL; + + snprintf(e->icq_cache_name, sizeof(e->icq_cache_name), + "%s_io_cq", e->elevator_name); + e->icq_cache = kmem_cache_create(e->icq_cache_name, e->icq_size, + e->icq_align, 0, NULL); + if (!e->icq_cache) + return -ENOMEM; + } + + /* register, don't allow duplicate names */ spin_lock(&elv_list_lock); - BUG_ON(elevator_find(e->elevator_name)); + if (elevator_find(e->elevator_name)) { + spin_unlock(&elv_list_lock); + if (e->icq_cache) + kmem_cache_destroy(e->icq_cache); + return -EBUSY; + } list_add_tail(&e->list, &elv_list); spin_unlock(&elv_list_lock); + /* print pretty message */ if (!strcmp(e->elevator_name, chosen_elevator) || (!*chosen_elevator && !strcmp(e->elevator_name, CONFIG_DEFAULT_IOSCHED))) @@ -902,14 +923,26 @@ void elv_register(struct elevator_type *e) printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name, def); + return 0; } EXPORT_SYMBOL_GPL(elv_register); void elv_unregister(struct elevator_type *e) { + /* unregister */ spin_lock(&elv_list_lock); list_del_init(&e->list); spin_unlock(&elv_list_lock); + + /* + * Destroy icq_cache if it exists. icq's are RCU managed. Make + * sure all RCU operations are complete before proceeding. + */ + if (e->icq_cache) { + rcu_barrier(); + kmem_cache_destroy(e->icq_cache); + e->icq_cache = NULL; + } } EXPORT_SYMBOL_GPL(elv_unregister); diff --git a/block/noop-iosched.c b/block/noop-iosched.c index 06389e9ef96d..413a0b1d788c 100644 --- a/block/noop-iosched.c +++ b/block/noop-iosched.c @@ -94,9 +94,7 @@ static struct elevator_type elevator_noop = { static int __init noop_init(void) { - elv_register(&elevator_noop); - - return 0; + return elv_register(&elevator_noop); } static void __exit noop_exit(void) diff --git a/include/linux/elevator.h b/include/linux/elevator.h index 04958ef53e62..d3d3e28cbfd4 100644 --- a/include/linux/elevator.h +++ b/include/linux/elevator.h @@ -78,10 +78,19 @@ struct elv_fs_entry { */ struct elevator_type { + /* managed by elevator core */ + struct kmem_cache *icq_cache; + + /* fields provided by elevator implementation */ struct elevator_ops ops; + size_t icq_size; + size_t icq_align; struct elv_fs_entry *elevator_attrs; char elevator_name[ELV_NAME_MAX]; struct module *elevator_owner; + + /* managed by elevator core */ + char icq_cache_name[ELV_NAME_MAX + 5]; /* elvname + "_io_cq" */ struct list_head list; }; @@ -127,7 +136,7 @@ extern void elv_drain_elevator(struct request_queue *); /* * io scheduler registration */ -extern void elv_register(struct elevator_type *); +extern int elv_register(struct elevator_type *); extern void elv_unregister(struct elevator_type *); /* |