[PATCH 0/2] Code cleanup and simplification

[PATCH 0/2] Code cleanup and simplification

[Damien Le Moal]

Mike, Mikulas,

A couple of patches to cleanup/simplify code. No functional change.

Damien Le Moal (2):
  dm: Remove unnecessary return in dm_zone_endio()
  dm: Simplify dm_io_complete()

 drivers/md/dm-zone.c |  2 --
 drivers/md/dm.c      | 11 ++---------
 2 files changed, 2 insertions(+), 11 deletions(-)

-- 
2.49.0

[PATCH 1/2] dm: Remove unnecessary return in dm_zone_endio()

[Damien Le Moal]

The return statement at the end of dm_zone_endio() is not needed.
Remove it.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
 drivers/md/dm-zone.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/md/dm-zone.c b/drivers/md/dm-zone.c
index 97ba70190821..4678076f5972 100644
--- a/drivers/md/dm-zone.c
+++ b/drivers/md/dm-zone.c
@@ -467,8 +467,6 @@ void dm_zone_endio(struct dm_io *io, struct bio *clone)
 			bdev_offset_from_zone_start(disk->part0,
 						    clone->bi_iter.bi_sector);
 	}
-
-	return;
 }
 
 static int dm_zone_need_reset_cb(struct blk_zone *zone, unsigned int idx,
-- 
2.49.0

Re: [PATCH 1/2] dm: Remove unnecessary return in dm_zone_endio()

[Christoph Hellwig]

Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>

[PATCH 2/2] dm: Simplify dm_io_complete()

[Damien Le Moal]

The local variable first_requeue is not needed since it is always equal
to dm_io_flagged(io, DM_IO_WAS_SPLIT). Call __dm_io_complete() passing
this value directly and remove first_requeue.

Also declare dm_io_complete() as inline to make sure it is inlined in
its single call site, thus avoiding the cost of a function call.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
 drivers/md/dm.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index f1da8fde549c..21920991ab28 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1024,10 +1024,8 @@ static void dm_wq_requeue_work(struct work_struct *work)
  *
  * 2) io->orig_bio points to new cloned bio which matches the requeued dm_io.
  */
-static void dm_io_complete(struct dm_io *io)
+static inline void dm_io_complete(struct dm_io *io)
 {
-	bool first_requeue;
-
 	/*
 	 * Only dm_io that has been split needs two stage requeue, otherwise
 	 * we may run into long bio clone chain during suspend and OOM could
@@ -1036,12 +1034,7 @@ static void dm_io_complete(struct dm_io *io)
 	 * Also flush data dm_io won't be marked as DM_IO_WAS_SPLIT, so they
 	 * also aren't handled via the first stage requeue.
 	 */
-	if (dm_io_flagged(io, DM_IO_WAS_SPLIT))
-		first_requeue = true;
-	else
-		first_requeue = false;
-
-	__dm_io_complete(io, first_requeue);
+	__dm_io_complete(io, dm_io_flagged(io, DM_IO_WAS_SPLIT));
 }
 
 /*
-- 
2.49.0

Re: [PATCH 2/2] dm: Simplify dm_io_complete()

[Christoph Hellwig]

Not sure if there is much of a point in second guessing the compiler
with the explicit inline statement (t'll probably inline anyway),
but the logic change looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>