diff options
Diffstat (limited to 'block/cfq-iosched.c')
| -rw-r--r-- | block/cfq-iosched.c | 54 |
1 files changed, 17 insertions, 37 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index ec24284e9d39..33e0b0c5e31d 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -31,8 +31,6 @@ static int cfq_slice_idle = HZ / 125; #define CFQ_KEY_ASYNC (0) -static DEFINE_SPINLOCK(cfq_exit_lock); - /* * for the hash of cfqq inside the cfqd */ @@ -1084,12 +1082,6 @@ static void cfq_free_io_context(struct io_context *ioc) complete(ioc_gone); } -static void cfq_trim(struct io_context *ioc) -{ - ioc->set_ioprio = NULL; - cfq_free_io_context(ioc); -} - static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) { if (unlikely(cfqq == cfqd->active_queue)) @@ -1101,6 +1093,10 @@ static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) static void __cfq_exit_single_io_context(struct cfq_data *cfqd, struct cfq_io_context *cic) { + list_del_init(&cic->queue_list); + smp_wmb(); + cic->key = NULL; + if (cic->cfqq[ASYNC]) { cfq_exit_cfqq(cfqd, cic->cfqq[ASYNC]); cic->cfqq[ASYNC] = NULL; @@ -1110,9 +1106,6 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd, cfq_exit_cfqq(cfqd, cic->cfqq[SYNC]); cic->cfqq[SYNC] = NULL; } - - cic->key = NULL; - list_del_init(&cic->queue_list); } @@ -1123,27 +1116,23 @@ static void cfq_exit_single_io_context(struct cfq_io_context *cic) { struct cfq_data *cfqd = cic->key; - WARN_ON(!irqs_disabled()); - if (cfqd) { request_queue_t *q = cfqd->queue; - spin_lock(q->queue_lock); + spin_lock_irq(q->queue_lock); __cfq_exit_single_io_context(cfqd, cic); - spin_unlock(q->queue_lock); + spin_unlock_irq(q->queue_lock); } } static void cfq_exit_io_context(struct io_context *ioc) { struct cfq_io_context *__cic; - unsigned long flags; struct rb_node *n; /* * put the reference this task is holding to the various queues */ - spin_lock_irqsave(&cfq_exit_lock, flags); n = rb_first(&ioc->cic_root); while (n != NULL) { @@ -1152,8 +1141,6 @@ static void cfq_exit_io_context(struct io_context *ioc) cfq_exit_single_io_context(__cic); n = rb_next(n); } - - spin_unlock_irqrestore(&cfq_exit_lock, flags); } static struct cfq_io_context * @@ -1248,15 +1235,12 @@ static inline void changed_ioprio(struct cfq_io_context *cic) spin_unlock(cfqd->queue->queue_lock); } -/* - * callback from sys_ioprio_set, irqs are disabled - */ -static int cfq_ioc_set_ioprio(struct io_context *ioc, unsigned int ioprio) +static void cfq_ioc_set_ioprio(struct io_context *ioc) { struct cfq_io_context *cic; struct rb_node *n; - spin_lock(&cfq_exit_lock); + ioc->ioprio_changed = 0; n = rb_first(&ioc->cic_root); while (n != NULL) { @@ -1265,10 +1249,6 @@ static int cfq_ioc_set_ioprio(struct io_context *ioc, unsigned int ioprio) changed_ioprio(cic); n = rb_next(n); } - - spin_unlock(&cfq_exit_lock); - - return 0; } static struct cfq_queue * @@ -1336,10 +1316,8 @@ out: static void cfq_drop_dead_cic(struct io_context *ioc, struct cfq_io_context *cic) { - spin_lock(&cfq_exit_lock); + WARN_ON(!list_empty(&cic->queue_list)); rb_erase(&cic->rb_node, &ioc->cic_root); - list_del_init(&cic->queue_list); - spin_unlock(&cfq_exit_lock); kmem_cache_free(cfq_ioc_pool, cic); atomic_dec(&ioc_count); } @@ -1385,7 +1363,6 @@ cfq_cic_link(struct cfq_data *cfqd, struct io_context *ioc, cic->ioc = ioc; cic->key = cfqd; - ioc->set_ioprio = cfq_ioc_set_ioprio; restart: parent = NULL; p = &ioc->cic_root.rb_node; @@ -1407,11 +1384,12 @@ restart: BUG(); } - spin_lock(&cfq_exit_lock); rb_link_node(&cic->rb_node, parent, p); rb_insert_color(&cic->rb_node, &ioc->cic_root); + + spin_lock_irq(cfqd->queue->queue_lock); list_add(&cic->queue_list, &cfqd->cic_list); - spin_unlock(&cfq_exit_lock); + spin_unlock_irq(cfqd->queue->queue_lock); } /* @@ -1441,6 +1419,10 @@ cfq_get_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) cfq_cic_link(cfqd, ioc, cic); out: + smp_read_barrier_depends(); + if (unlikely(ioc->ioprio_changed)) + cfq_ioc_set_ioprio(ioc); + return cic; err: put_io_context(ioc); @@ -1945,7 +1927,6 @@ static void cfq_exit_queue(elevator_t *e) cfq_shutdown_timer_wq(cfqd); - spin_lock(&cfq_exit_lock); spin_lock_irq(q->queue_lock); if (cfqd->active_queue) @@ -1960,7 +1941,6 @@ static void cfq_exit_queue(elevator_t *e) } spin_unlock_irq(q->queue_lock); - spin_unlock(&cfq_exit_lock); cfq_shutdown_timer_wq(cfqd); @@ -2149,7 +2129,7 @@ static struct elevator_type iosched_cfq = { .elevator_may_queue_fn = cfq_may_queue, .elevator_init_fn = cfq_init_queue, .elevator_exit_fn = cfq_exit_queue, - .trim = cfq_trim, + .trim = cfq_free_io_context, }, .elevator_attrs = cfq_attrs, .elevator_name = "cfq", |