diff options
Diffstat (limited to 'fs/btrfs/block-group.c')
| -rw-r--r-- | fs/btrfs/block-group.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 3f8b1cbbbc43..684401aa014a 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1606,6 +1606,24 @@ void btrfs_reclaim_bgs_work(struct work_struct *work) up_write(&space_info->groups_sem); goto next; } + if (bg->used == 0) { + /* + * It is possible that we trigger relocation on a block + * group as its extents are deleted and it first goes + * below the threshold, then shortly after goes empty. + * + * In this case, relocating it does delete it, but has + * some overhead in relocation specific metadata, looking + * for the non-existent extents and running some extra + * transactions, which we can avoid by using one of the + * other mechanisms for dealing with empty block groups. + */ + if (!btrfs_test_opt(fs_info, DISCARD_ASYNC)) + btrfs_mark_bg_unused(bg); + spin_unlock(&bg->lock); + up_write(&space_info->groups_sem); + goto next; + } spin_unlock(&bg->lock); /* Get out fast, in case we're unmounting the filesystem */ |