2.6.24

 block

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 54dc054..13553e0 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;
@@ -1443,8 +1452,11 @@ cfq_get_queue(struct cfq_data *cfqd, int is_sync, struct task_struct *tsk,
       cfqq = *async_cfqq;
    }
 
-   if (!cfqq)
+   if (!cfqq) {
       cfqq = cfq_find_alloc_queue(cfqd, is_sync, tsk, gfp_mask);
+      if (!cfqq)
+         return NULL;
+   }
 
    /*
     * pin the queue now that it's allocated, scheduler exit will prune it
@@ -2033,17 +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);
@@ -2053,7 +2062,7 @@ static void cfq_shutdown_timer_wq(struct cfq_data *cfqd)
 {
    del_timer_sync(&cfqd->idle_slice_timer);
    del_timer_sync(&cfqd->idle_class_timer);
-   blk_sync_queue(cfqd->queue);
+   kblockd_flush_work(&cfqd->unplug_work);
 }
 
 static void cfq_put_async_queues(struct cfq_data *cfqd)
@@ -2065,9 +2074,10 @@ static void cfq_put_async_queues(struct cfq_data *cfqd)
          cfq_put_queue(cfqd->async_cfqq[0][i]);
       if (cfqd->async_cfqq[1][i])
          cfq_put_queue(cfqd->async_cfqq[1][i]);
-      if (cfqd->async_idle_cfqq)
-         cfq_put_queue(cfqd->async_idle_cfqq);
    }
+
+   if (cfqd->async_idle_cfqq)
+      cfq_put_queue(cfqd->async_idle_cfqq);
 }
 
 static void cfq_exit_queue(elevator_t *e)
@@ -2122,6 +2132,7 @@ static void *cfq_init_queue(struct request_queue *q)
 
    INIT_WORK(&cfqd->unplug_work, cfq_kick_queue);
 
+   cfqd->last_end_request = jiffies;
    cfqd->cfq_quantum = cfq_quantum;
    cfqd->cfq_fifo_expire[0] = cfq_fifo_expire[0];
    cfqd->cfq_fifo_expire[1] = cfq_fifo_expire[1];
@@ -2268,8 +2279,6 @@ static struct elevator_type iosched_cfq = {
 
 static int __init cfq_init(void)
 {
-   int ret;
-
    /*
     * could be 0 on HZ < 1000 setups
     */
@@ -2281,11 +2290,9 @@ static int __init cfq_init(void)
    if (cfq_slab_setup())
       return -ENOMEM;
 
-   ret = elv_register(&iosched_cfq);
-   if (ret)
-      cfq_slab_kill();
+   elv_register(&iosched_cfq);
 
-   return ret;
+   return 0;
 }
 
 static void __exit cfq_exit(void)