diff options
Diffstat (limited to 'block/ll_rw_blk.c')
| -rw-r--r-- | block/ll_rw_blk.c | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index 1755c053fd68..7eb36c53f4b7 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -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, }; @@ -3439,7 +3452,12 @@ void end_that_request_last(struct request *req, int uptodate) if (unlikely(laptop_mode) && blk_fs_request(req)) laptop_io_completion(); - if (disk && blk_fs_request(req)) { + /* + * Account IO completion. bar_rq isn't accounted as a normal + * IO on queueing nor completion. Accounting the containing + * request is enough. + */ + if (disk && blk_fs_request(req) && req != &req->q->bar_rq) { unsigned long duration = jiffies - req->start_time; const int rw = rq_data_dir(req); |