On Mon, 2017-10-16 at 05:49:14 UTC, Santosh Sivaraj wrote: > Current vDSO64 implementation does not have support for coarse clocks > (CLOCK_MONOTONIC_COARSE, CLOCK_REALTIME_COARSE), for which it falls back > to system call, increasing the response time, vDSO implementation reduces > the cycle time. Below is a benchmark of the difference in execution times. > > (Non-coarse clocks are also included just for completion) > > clock-gettime-realtime: syscall: 172 nsec/call > clock-gettime-realtime: libc: 28 nsec/call > clock-gettime-realtime: vdso: 22 nsec/call > clock-gettime-monotonic: syscall: 171 nsec/call > clock-gettime-monotonic: libc: 30 nsec/call > clock-gettime-monotonic: vdso: 25 nsec/call > clock-gettime-realtime-coarse: syscall: 153 nsec/call > clock-gettime-realtime-coarse: libc: 16 nsec/call > clock-gettime-realtime-coarse: vdso: 10 nsec/call > clock-gettime-monotonic-coarse: syscall: 167 nsec/call > clock-gettime-monotonic-coarse: libc: 17 nsec/call > clock-gettime-monotonic-coarse: vdso: 11 nsec/call > > CC: Benjamin Herrenschmidt <b...@kernel.crashing.org> > Reviewed-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com> > Signed-off-by: Santosh Sivaraj <sant...@fossix.org>
Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/5c929885f1bb4b77f85b1769c49405 cheers
