diff options
Diffstat (limited to 'block/ll_rw_blk.c')
| -rw-r--r-- | block/ll_rw_blk.c | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index e112d1a5dab..eac48bec147 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -1554,7 +1554,7 @@ void blk_plug_device(request_queue_t *q) * don't plug a stopped queue, it must be paired with blk_start_queue() * which will restart the queueing */ - if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags)) + if (blk_queue_stopped(q)) return; if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) { @@ -1587,7 +1587,7 @@ EXPORT_SYMBOL(blk_remove_plug); */ void __generic_unplug_device(request_queue_t *q) { - if (unlikely(test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags))) + if (unlikely(blk_queue_stopped(q))) return; if (!blk_remove_plug(q)) @@ -1732,8 +1732,21 @@ void blk_run_queue(struct request_queue *q) spin_lock_irqsave(q->queue_lock, flags); blk_remove_plug(q); - if (!elv_queue_empty(q)) - q->request_fn(q); + + /* + * Only recurse once to avoid overrunning the stack, let the unplug + * handling reinvoke the handler shortly if we already got there. + */ + if (!elv_queue_empty(q)) { + if (!test_and_set_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) { + q->request_fn(q); + clear_bit(QUEUE_FLAG_REENTER, &q->queue_flags); + } else { + blk_plug_device(q); + kblockd_schedule_work(&q->unplug_work); + } + } + spin_unlock_irqrestore(q->queue_lock, flags); } EXPORT_SYMBOL(blk_run_queue); @@ -3385,7 +3398,7 @@ static int blk_cpu_notify(struct notifier_block *self, unsigned long action, } -static struct notifier_block __devinitdata blk_cpu_notifier = { +static struct notifier_block blk_cpu_notifier = { .notifier_call = blk_cpu_notify, }; |