Wolfgang Grandegger wrote: > Gilles Chanteperdrix wrote: >> Wolfgang Grandegger wrote: >>> Gilles Chanteperdrix wrote: >>>> For architectures with a high-resolution counter, >>>> clock_gettime(CLOCK_MONOTONIC) is a xenomai service which uses the >>>> counter and does not issue any syscall, this includes arm unless you >>>> configured xenomai with --enable-arm-arch=generic or with >>>> --disable-arm-tsc, and this probably includes powerpc. >>>> >>> clock_gettime() is wrapped to __wrap_clock_gettime(), which does a syscall: >>> >>> http://www.rts.uni-hannover.de/xenomai/lxr/source/src/skins/posix/clock.c?v=SVN-trunk#058 >>> >>> Have I missed something? >> Yes, read the code again. > > I was aware of CONFIG_XENO_HW_DIRECT_TSC but didn't look it up correctly > :-(. It is set for my ARM but not for my PowerPC system. Which explains > some differences. >
We do have direct TSC readings on powerpc as well by looking at the timebase register from userland, but this only applies to rt_native_tsc(), or clock_gettime() when using CLOCK_MONOTONIC in aperiodic mode. > Wolfgang. > > > _______________________________________________ > Xenomai-help mailing list > Xenomai-help@gna.org > https://mail.gna.org/listinfo/xenomai-help > -- Philippe. _______________________________________________ Xenomai-help mailing list Xenomai-help@gna.org https://mail.gna.org/listinfo/xenomai-help
