Symbol: BTRFS_DELAYED_WRITEBACK
fs/btrfs/delayed-inode.c
1372
} while ((async_work->nr == 0 && total_done < BTRFS_DELAYED_WRITEBACK)
fs/btrfs/delayed-inode.c
1433
if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {