Re: [PATCH 05/10] block: remove per-queue plugging

[NeilBrown <neilb@suse.de>]

[[NOTE to dm-devel people - one of the patches here remove some
 now-unused code from dm-raid.c plus a declaration from device-mapper.h ]]]


On Mon, 18 Apr 2011 10:10:18 +0200 Jens Axboe <jaxboe@fusionio.com> wrote:

> On 2011-04-18 09:25, NeilBrown wrote:

> >>> Therefore md cannot put anything useful on the list in 'struct blk_plug'.
> > 
> > That is the heart of the problem.
> 
> Hmm, I don't really see a way to avoid the list in that case. You really
> do need some way to queue items, a single callback or flag or pointer
> will not suffice.
> 
> I've added the patch and removed the (now) useless ->unplugged_fn
> callback. I suggest you base your md changes on top of my for-linus
> branch and tell me when you are confident it looks good, then I'll pull
> in your MD changes and submit them later today.
> 
> OK with you?
> 

Yes, that's perfect.  Thanks.

All of my plugging-related patches are now in a 'for-jens' branch:

The following changes since commit 99e22598e9a8e0a996d69c8c0f6b7027cb57720a:

  block: drop queue lock before calling __blk_run_queue() for kblockd punt (2011-04-18 09:59:55 +0200)

are available in the git repository at:
  git://neil.brown.name/md for-jens

NeilBrown (6):
      md: use new plugging interface for RAID IO.
      md/dm - remove remains of plug_fn callback.
      md - remove old plugging code.
      md: provide generic support for handling unplug callbacks.
      md: incorporate new plugging into raid5.
      md: fix up raid1/raid10 unplugging.

 drivers/md/dm-raid.c          |    8 ----
 drivers/md/md.c               |   87 +++++++++++++++++++++-------------------
 drivers/md/md.h               |   26 ++----------
 drivers/md/raid1.c            |   29 +++++++-------
 drivers/md/raid10.c           |   27 ++++++-------
 drivers/md/raid5.c            |   61 ++++++++++++----------------
 drivers/md/raid5.h            |    2 -
 include/linux/device-mapper.h |    1 -
 8 files changed, 103 insertions(+), 138 deletions(-)


Thanks,
NeilBrown