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Or is this > code just dormant as of now? iirc linux devs asked that it is only used in vdso so that it is under the kernel's control in case there are implementation issues (vdso is easy to disable and on some system it got disabled for timer reasons). is hp-timing.h for some internal benchmarks only? if no, then i think we should get the opinion of linux maintainers before we use this in glibc.