[PATCH 0/7] btrfs: avoid some unnecessary commit of empty transactions

[fdmanana@kernel.org]

From: Filipe Manana <fdmanana@suse.com>

A few places can unnecessarily create an empty transaction and then commit
it, when the goal is just to catch the current transaction and wait for
its commit to complete. This results in wasting IO, time and rotation of
the precious backup roots in the super block. Details in the change logs.
The patches are all independent, except patch 4 that applies on top of
patch 3 (but could have been done in any order really, they are independent).

Filipe Manana (7):
  btrfs: qgroup: avoid start/commit empty transaction when flushing reservations
  btrfs: avoid create and commit empty transaction when committing super
  btrfs: send: make ensure_commit_roots_uptodate() simpler and more efficient
  btrfs: send: avoid create/commit empty transaction at ensure_commit_roots_uptodate()
  btrfs: scrub: avoid create/commit empty transaction at finish_extent_writes_for_zoned()
  btrfs: add and use helper to commit the current transaction
  btrfs: send: get rid of the label and gotos at ensure_commit_roots_uptodate()

 fs/btrfs/disk-io.c     |  8 +-------
 fs/btrfs/qgroup.c      | 31 +++++--------------------------
 fs/btrfs/scrub.c       |  6 +-----
 fs/btrfs/send.c        | 32 ++++++++------------------------
 fs/btrfs/space-info.c  |  9 +--------
 fs/btrfs/super.c       | 11 +----------
 fs/btrfs/transaction.c | 19 +++++++++++++++++++
 fs/btrfs/transaction.h |  1 +
 8 files changed, 37 insertions(+), 80 deletions(-)

-- 
2.43.0