/usr/lib/linux-tools/3.13.0-43-lowlatency/x86_energy_perf_policy is in linux-tools-3.13.0-43-lowlatency 3.13.0-43.72.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/linux-tools/3.13.0-43-lowlatency/../../linux-tools-3.13.0-43/x86_energy_perf_policy