tsc_gethrtimeunscaled_delta
gethrtimeunscaledf = tsc_gethrtimeunscaled_delta;
gethrtimeunscaledf = tsc_gethrtimeunscaled_delta;
extern hrtime_t tsc_gethrtimeunscaled_delta(void);
*gethrtimeunscaledf == tsc_gethrtimeunscaled_delta);
(*gethrtimeunscaledf == tsc_gethrtimeunscaled_delta);