From: Mikulas Patocka This doesn't fix any bug, just moves wake_up immediately after decrementing md->pending, for better code readability. It must be clear to anyone manipulating md->pending to wake up the queue if md->pending reaches zero, so move the wakeup as close to the decrementing as possible. Signed-off-by: Mikulas Patocka Signed-off-by: Alasdair G Kergon --- drivers/md/dm.c | 10 +++++----- 1 files changed, 5 insertions(+), 5 deletions(-) Index: linux-2.6.28-rc4/drivers/md/dm.c =================================================================== --- linux-2.6.28-rc4.orig/drivers/md/dm.c 2008-11-13 23:18:38.000000000 +0000 +++ linux-2.6.28-rc4/drivers/md/dm.c 2008-11-13 23:22:00.000000000 +0000 @@ -375,7 +375,7 @@ static void start_io_acct(struct dm_io * dm_disk(md)->part0.in_flight = atomic_inc_return(&md->pending); } -static int end_io_acct(struct dm_io *io) +static void end_io_acct(struct dm_io *io) { struct mapped_device *md = io->md; struct bio *bio = io->bio; @@ -391,7 +391,9 @@ static int end_io_acct(struct dm_io *io) dm_disk(md)->part0.in_flight = pending = atomic_dec_return(&md->pending); - return !pending; + /* nudge anyone waiting on suspend queue */ + if (!pending) + wake_up(&md->wait); } /* @@ -499,9 +501,7 @@ static void dec_pending(struct dm_io *io spin_unlock_irqrestore(&io->md->pushback_lock, flags); } - if (end_io_acct(io)) - /* nudge anyone waiting on suspend queue */ - wake_up(&io->md->wait); + end_io_acct(io); if (io->error != DM_ENDIO_REQUEUE) { blk_add_trace_bio(io->md->queue, io->bio,