[Xenomai-help] Unexpected switch to secondary mode

[Johan Borkhuis <j.borkhuis@domain.hid>]

I am experiencing an unexpected switch to secondary mode in a 
rt_timer_tsc2ns call from userspace.

The following code give a switch:
    SRTIME timeStamp;
    timeStamp = rt_timer_tsc2ns(rt_timer_tsc());
    while((rt_timer_tsc2ns(rt_timer_tsc()) - timeStamp) < (usecs*1000)) {}

while the following code does not:
    RTIME timeStamp;
    timeStamp = rt_timer_tsc();
    while((rt_timer_tsc() - timeStamp) < (usecs*1000)) {}

(I know that the second example causes a longer timeout, but this was to 
show the testcase).

When splitting up the 2nd line in the first example I see that the 
rt_timer_tsc() call does not cause a switch, but the rt_timer_tsc2ns 
does. What am I doing wrong here?

I am using Xenomai-2.3.2.

Kind regards,
    Johan Borkhuis