[0/2] btrfs: zoned: activate new BG only from extent allocation context

Message

Naohiro Aota March 16, 2022, 2:09 p.m. UTC

In btrfs_make_block_group(), we activate the allocated block group,
expecting that the block group is soon used for the extent allocation.

With a lot of IOs, btrfs_async_reclaim_data_space() tries to prepare
for them by pre-allocating data block groups. That preallocation can
consume all the active zone counting. It is OK if they are soon
written and filled. However, that's not the case. As a result, an
allocation of non-data block groups fails due to the lack of an active
zone resource.

This series fixes the issue by activating a new block group only when
it's called from find_free_extent(). This series introduces
CHUNK_ALLOC_FORCE_FOR_EXTENT in btrfs_chunk_alloc_enum to distinguish
the context.

Naohiro Aota (2):
  btrfs: return allocated block group from do_chunk_alloc()
  btrfs: zoned: activate block group only for extent allocation

 fs/btrfs/block-group.c | 36 +++++++++++++++++++++++++++---------
 fs/btrfs/block-group.h |  1 +
 fs/btrfs/extent-tree.c |  2 +-
 3 files changed, 29 insertions(+), 10 deletions(-)