ORC unwinder

modulename: unwind_orc.ko

configname: CONFIG_UNWINDER_ORC

Choose kernel unwinder
└─>ORC unwinder
In linux kernel since version 3.10 (release Date: 2013-06-30)  
This option enables the ORC (Oops Rewind Capability) unwinder for
unwinding kernel stack traces. It uses a custom data format which is
a simplified version of the DWARF Call Frame Information standard.

This unwinder is more accurate across interrupt entry frames than the
frame pointer unwinder. It also enables a 5-10% performance
improvement across the entire kernel compared to frame pointers.

Enabling this option will increase the kernel's runtime memory usage
by roughly 2-4MB, depending on your kernel config.

source code: