[PATCH v4 0/6] A variety of lock contention fixes

[Josef Bacik <josef@toxicpanda.com>]

v3->v4:
- I accidentally sent out the v1 version of these patches, because I had fixed
  them on another machine.  This is the proper set with the changes from v2 that
  are properly rebased onto misc-next.

v2->v3:
- Added Nikolay's reviewed by for the second patch.
- Rebased onto the latest misc-next.

v1->v2:
- Fixed the log messages that Nikolay pointed out.
- Added Nikolay's reviewed by for the first patch.
- Removed the unneeded mb for flushing.

--- Original email ---
Hello,

I've been running some stress tests recently in order to try and reproduce some
problems I've tripped over in relocation.  Most of this series is a reposting of
patches I wrote when debugging related issues for Zygo that got lost.  I've
updated one of them to make the lock contention even better, making it so I have
to ramp up my stress test loops because it now finishes way too fast.  Thanks,

Josef

Josef Bacik (6):
  btrfs: do not block on deleted bgs mutex in the cleaner
  btrfs: only let one thread pre-flush delayed refs in commit
  btrfs: delayed refs pre-flushing should only run the heads we have
  btrfs: only run delayed refs once before committing
  btrfs: stop running all delayed refs during snapshot
  btrfs: run delayed refs less often in commit_cowonly_roots

 fs/btrfs/block-group.c | 11 +++++--
 fs/btrfs/delayed-ref.h | 12 +++----
 fs/btrfs/extent-tree.c |  2 +-
 fs/btrfs/transaction.c | 74 ++++++++++++++++--------------------------
 4 files changed, 43 insertions(+), 56 deletions(-)

-- 
2.26.2