Gilles Chanteperdrix wrote:
Right. We are approximating a fraction with another fraction. But my
first impression remains: I do not like the idea of making
xnarch_ns_to_tsc wrong because xnarch_tsc_to_ns is wrong.

Well, my first impression was originally the same: If we still need llimd in the ns-to-tsc patch, then we should keep the precise way. But that was wrong as this thread demonstrated. We have to ensure that ns_to_tsc(tsc_to_ns(x)) remains x with only minor last-digit errors. So either use scaled math parameters in both ways or fall back to the original calculation.

However the final decision for 2.5 is (pro or contra scaled math), at least for 2.4.x we have to fix things now without turning the upside down. That means apply my patch or revert scaled-math optimizations for all archs.


Attachment: signature.asc
Description: OpenPGP digital signature

Xenomai-core mailing list

Reply via email to