SG: work with the SCSI fixed maximum allocations.

[linux-2.6-omap-h63xx.git] / block / cfq-iosched.c

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 54dc05439009d09968572e6f12ce30d0fef151e8..13553e015d7203f244db2e411884c56cbee1bc26 100644 (file)
--- 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)