This patch will add the following trace events:
1) btrfs_remove_block_group
For btrfs_remove_block_group() function.
Triggered when a block group is really removed.
2) btrfs_add_unused_block_group
Triggered which block group is added to unused_bgs list.
3) btrfs_skip_unused_block_group
Triggered which unused block group is not deleted.
These trace events is pretty handy to debug case related to block group
auto remove.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>