dm: move pending queue wake_up end_io_acct

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 <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Mikulas Patocka 2008-11-13 23:39:10 +00:00 committed by Alasdair G Kergon
parent 14e98c5ca8
commit d221d2e776
1 changed files with 5 additions and 5 deletions

View File

@ -375,7 +375,7 @@ static void start_io_acct(struct dm_io *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, int error)
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,