X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=block%2Fll_rw_blk.c;h=7eb36c53f4b7868247141a105ef82e8be3e2d96f;hb=d90d2c385d4d832428d1e51c2a7edeef39c822f5;hp=1755c053fd68ce648ba90bcbc3c7132ac23d8ad1;hpb=7daac4902053045450fa29db42aba19a4581f850;p=linux-2.6

diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index 1755c053fd..7eb36c53f4 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);