From: Jens Axboe <axboe@suse.de>

The 'unplug on queued exceeding unplug threshold' logic only works for file
system requests currently, since it's in __make_request().  Move it where
it belongs, in elv_add_request().  This way it works for queued block sg
requests as well.

Signed-Off-By: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 25-akpm/drivers/block/elevator.c  |    8 ++++++++
 25-akpm/drivers/block/ll_rw_blk.c |   11 ++++-------
 25-akpm/include/linux/blkdev.h    |    1 +
 3 files changed, 13 insertions(+), 7 deletions(-)

diff -puN drivers/block/elevator.c~blk-move-threshold-unplugging drivers/block/elevator.c
--- 25/drivers/block/elevator.c~blk-move-threshold-unplugging	Wed Jun  9 14:27:19 2004
+++ 25-akpm/drivers/block/elevator.c	Wed Jun  9 14:27:19 2004
@@ -181,6 +181,14 @@ void __elv_add_request(request_queue_t *
 
 	rq->q = q;
 	q->elevator.elevator_add_req_fn(q, rq, where);
+
+	if (blk_queue_plugged(q)) {
+		int nrq = q->rq.count[READ] + q->rq.count[WRITE] - q->in_flight;
+
+		if (nrq == q->unplug_thresh)
+			__generic_unplug_device(q);
+	}
+
 }
 
 void elv_add_request(request_queue_t *q, struct request *rq, int where,
diff -puN drivers/block/ll_rw_blk.c~blk-move-threshold-unplugging drivers/block/ll_rw_blk.c
--- 25/drivers/block/ll_rw_blk.c~blk-move-threshold-unplugging	Wed Jun  9 14:27:19 2004
+++ 25-akpm/drivers/block/ll_rw_blk.c	Wed Jun  9 14:27:19 2004
@@ -1162,7 +1162,7 @@ EXPORT_SYMBOL(blk_remove_plug);
 /*
  * remove the plug and let it rip..
  */
-static inline void __generic_unplug_device(request_queue_t *q)
+inline void __generic_unplug_device(request_queue_t *q)
 {
 	if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags))
 		return;
@@ -1176,6 +1176,7 @@ static inline void __generic_unplug_devi
 	if (elv_next_request(q))
 		q->request_fn(q);
 }
+EXPORT_SYMBOL(__generic_unplug_device);
 
 /**
  * generic_unplug_device - fire a request queue
@@ -2389,13 +2390,9 @@ get_rq:
 out:
 	if (freereq)
 		__blk_put_request(q, freereq);
+	if (bio_sync(bio))
+		__generic_unplug_device(q);
 
-	if (blk_queue_plugged(q)) {
-		int nrq = q->rq.count[READ] + q->rq.count[WRITE] - q->in_flight;
-
-		if (nrq == q->unplug_thresh || bio_sync(bio))
-			__generic_unplug_device(q);
-	}
 	spin_unlock_irq(q->queue_lock);
 	return 0;
 
diff -puN include/linux/blkdev.h~blk-move-threshold-unplugging include/linux/blkdev.h
--- 25/include/linux/blkdev.h~blk-move-threshold-unplugging	Wed Jun  9 14:27:19 2004
+++ 25-akpm/include/linux/blkdev.h	Wed Jun  9 14:27:19 2004
@@ -614,6 +614,7 @@ extern int blkdev_scsi_issue_flush_fn(re
 extern int blk_rq_map_sg(request_queue_t *, struct request *, struct scatterlist *);
 extern void blk_dump_rq_flags(struct request *, char *);
 extern void generic_unplug_device(request_queue_t *);
+extern inline void __generic_unplug_device(request_queue_t *);
 extern long nr_blockdev_pages(void);
 
 int blk_get_queue(request_queue_t *);
_