Karl Reichert wrote: > Hmm ... what is the difference between rt_timer_read, rt_timer_inquire and > rt_timer_tsc? I think rt_timer_inquire is giving the same results (and a > little more, the period) like the other two ones, but in one call? > > As I understand, TSC is a reliable value on single processor machines with > CONFIG_CPU_FREQ, CONFIG_ACPI_PROCESSOR and CONFIG_APM disabled?! So I can > use rt_timer_tsc?! Or should I better use rt_timer_read? (Please see above > for my UseCase)
rt_timer_tsc has less overhead than rt_timer_read (it does not issue a syscall, and it does not do any conversion). On the other hand, rt_timer_read gives you an absolute value whose reference is the well known 1st january 1970. With rt_timer_inquire, you get rt_timer_tsc and rt_timer_read at the same time, and you know the relation between the two values. -- Gilles. ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ RTnet-users mailing list RTnet-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/rtnet-users