Reproduce by:
echo foo > foo sudo setcap cap_perfmon+ep foo
Result: "Fatal error: Invalid argument"
sudo setcap cap_net_raw_ep foo
Result: blank (success)
getcap foo foo = cap_net_raw+ep
So cap_net_raw works, but cap_perfmon is not implemented.
Reproduce by:
echo foo > foo
sudo setcap cap_perfmon+ep foo
Result: "Fatal error: Invalid argument"
sudo setcap cap_net_raw_ep foo
Result: blank (success)
getcap foo
foo = cap_net_raw+ep
So cap_net_raw works, but cap_perfmon is not implemented.