This is a note to let you know that I've just added the patch titled btrfs: move out now unused BG from the reclaim list to the 6.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: btrfs-move-out-now-unused-bg-from-the-reclaim-list.patch and it can be found in the queue-6.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e72c4956eedf6f4788fe79823670603226f55651 Author: Naohiro Aota <naota@xxxxxxxxx> Date: Tue Jun 6 14:36:34 2023 +0900 btrfs: move out now unused BG from the reclaim list [ Upstream commit a9f189716cf15913c453299d72f69c51a9b0f86b ] An unused block group is easy to remove to free up space and should be reclaimed fast. Such block group can often already be a target of the reclaim process. As we check list_empty(&bg->bg_list), we keep it in the reclaim list. That block group is never reclaimed until the file system is filled e.g. up to 75%. Instead, we can move unused block group to the unused list and delete it fast. Fixes: 18bb8bbf13c1 ("btrfs: zoned: automatically reclaim zones") CC: stable@xxxxxxxxxxxxxxx # 5.15+ Reviewed-by: Filipe Manana <fdmanana@xxxxxxxx> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx> Signed-off-by: Naohiro Aota <naohiro.aota@xxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 2a60033d907bf..78d57f1efe1d0 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1665,11 +1665,14 @@ void btrfs_mark_bg_unused(struct btrfs_block_group *bg) { struct btrfs_fs_info *fs_info = bg->fs_info; + trace_btrfs_add_unused_block_group(bg); spin_lock(&fs_info->unused_bgs_lock); if (list_empty(&bg->bg_list)) { btrfs_get_block_group(bg); - trace_btrfs_add_unused_block_group(bg); list_add_tail(&bg->bg_list, &fs_info->unused_bgs); + } else { + /* Pull out the block group from the reclaim_bgs list. */ + list_move_tail(&bg->bg_list, &fs_info->unused_bgs); } spin_unlock(&fs_info->unused_bgs_lock); }