X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=block%2Fll_rw_blk.c;h=7eb36c53f4b7868247141a105ef82e8be3e2d96f;hb=5b542e4422766d644ca303b8a47b27ec9eeeef3a;hp=e112d1a5dab6b8c2dcae45e2a6b18bbfc4529760;hpb=f1f76afd71e0f17af9a35fcb649f4bab53304a4d;p=linux-2.6 diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index e112d1a5da..7eb36c53f4 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, }; @@ -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);