Enable extra timekeeping sanity checking

configname: CONFIG_DEBUG_TIMEKEEPING

Linux Kernel Configuration
└─>Kernel hacking
└─>Enable extra timekeeping sanity checking
In linux kernel since version 4.1 (release Date: 2015-06-21)  
This option will enable additional timekeeping sanity checks
which may be helpful when diagnosing issues where timekeeping
problems are suspected.

This may include checks in the timekeeping hotpaths, so this
option may have a (very small) performance impact to some
workloads.

If unsure, say N.