diff options
Diffstat (limited to 'block/cfq-iosched.c')
| -rw-r--r-- | block/cfq-iosched.c | 28 |
1 files changed, 17 insertions, 11 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 6831a758d54..0b4a4790557 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -789,6 +789,20 @@ static inline void cfq_slice_expired(struct cfq_data *cfqd, int timed_out) __cfq_slice_expired(cfqd, cfqq, timed_out); } +static int start_idle_class_timer(struct cfq_data *cfqd) +{ + unsigned long end = cfqd->last_end_request + CFQ_IDLE_GRACE; + unsigned long now = jiffies; + + if (time_before(now, end) && + time_after_eq(now, cfqd->last_end_request)) { + mod_timer(&cfqd->idle_class_timer, end); + return 1; + } + + return 0; +} + /* * Get next queue for service. Unless we have a queue preemption, * we'll simply select the first cfqq in the service tree. @@ -805,19 +819,14 @@ static struct cfq_queue *cfq_get_next_queue(struct cfq_data *cfqd) cfqq = rb_entry(n, struct cfq_queue, rb_node); if (cfq_class_idle(cfqq)) { - unsigned long end; - /* * if we have idle queues and no rt or be queues had * pending requests, either allow immediate service if * the grace period has passed or arm the idle grace * timer */ - end = cfqd->last_end_request + CFQ_IDLE_GRACE; - if (time_before(jiffies, end)) { - mod_timer(&cfqd->idle_class_timer, end); + if (start_idle_class_timer(cfqd)) cfqq = NULL; - } } return cfqq; @@ -2036,17 +2045,14 @@ out_cont: static void cfq_idle_class_timer(unsigned long data) { struct cfq_data *cfqd = (struct cfq_data *) data; - unsigned long flags, end; + unsigned long flags; spin_lock_irqsave(cfqd->queue->queue_lock, flags); /* * race with a non-idle queue, reset timer */ - end = cfqd->last_end_request + CFQ_IDLE_GRACE; - if (!time_after_eq(jiffies, end)) - mod_timer(&cfqd->idle_class_timer, end); - else + if (!start_idle_class_timer(cfqd)) cfq_schedule_dispatch(cfqd); spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); |