Periodic scheduling of 2 kernel tasks (different modules)

Hello,

I am a beginner in rtai (and kernel module programming). Kindly answer
below queries.

*Question 1:*
I have written 2 simple rtai kernel modules using periodic scheduling, both
of them.
One module prints one number each period (starting from 1 to 10
incrementing each period) and other one does the same thing -1 to -10
decrementing each period.
There are no other rtai kernel modules that I have inserted except the two
(apart from rtai hal,sched etc).

In this scenario, where no other real time modules are inserted by me,
shouldn't the behaviour be consistent? It is not happening so.
If in a cycle it prints 1,-1,2,-2,3,-3,4,-4,5,-5,6,-6,7,-7,8,-8,9,-9,10,-10
in other cycle of execution (I do rmmod and insmod again), it prints some
other pattern like 1,2,3,4,-1,-2,5,6, etc

As long as same logic is present in each rtai kernel modules and no new
rtai kernel module inserted or deleted, the output should be same each
execution in real time. But it is not so. I did not get this. Please help
me understand.

*Question 2:*
I have seen in some of the example code samples, *rt_set_oneshot_mode()* is
called and then *start_rt_timer(1)*, then *rt_task_init()* and
*rt_task_make_periodic()* . Does one shot mode setting of the timer have
any effect in the sequence of calls? I understand the timer can be either
set to one shot mode or periodic mode. I understand we are setting one shot
mode initially and then overriding the setting by calling
*rt_task_make_periodic()*. Is my understanding correct? I mean it is same
as removing the call to rt_set_oneshot_mode()

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*  rt_set_oneshot_mode();
timer_period_count=nano2count(timer_period_ns);
start_rt_timer(timer_period_count);
rt_task_init_cpuid(&tau_2,  /* pointer to our task structure
*/                 f_tau_2,       /* the task function */
0,             /* arg for f_tau_2 */                 1024,          /* size
of the stack */                 100,           /* tau_2 has priority = 100
*/                 0,             /* we don't use floating point unit
*/                 0,             /* we don't use signals
*/                 0);            /* run on CPU 0 */
rt_task_make_periodic(&tau_1, /* pointer to our task structure
*/                                  /* start 2 timer_periods from now
*/                          rt_get_time() +
2*timer_period_count,                          5*timer_period_count); /*
recurring period (ignored in one-shot) */*
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Thanks and regards,
Bhargav

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