ok,

here is the code.
The code essentially cerates two tasks low and high priority task.
The low priority task has priority as 3 and high as 98

When i execute this initally everything goes smoothly as low priority task
starts running with priority thread 3 , it sleeps so then the high priority
thread runs with priority 98. But before the high priority thread finishes
the for loop for 7 times the low priority thread prempts it and starts
running with priority = 98.

This is what has baffled me?

#include <stdio.h>
#include <unistd.h>
#include <sys/mman.h>
#include <native/task.h>
#include <native/timer.h>

RT_TASK task1;
RT_TASK task2;
RT_TASK_INFO info;

void low_task(void *arg)
{
        rt_task_inquire(&task1, &info);
        printf("Priority of low task %d\n", info.cprio);

        rt_task_sleep(3000000000);

       while(1)
        {
                printf("Priority of Low task %d\n",info.cprio);
        }

}

void high_task(void *arg)
{
        unsigned int i;
        rt_task_inquire(&task2, &info);
        printf("Priority of high task before sleep %d\n", info.cprio);
        for(i=0;i<7;i++)
        {

                printf("Priority of High Priotity task1 %d\n",info.cprio);
                rt_task_sleep(1000000000);
        }

        printf("High priority thread goin to sleep %d\n",info.cprio);
        rt_task_sleep(3000000000);

        for(i=0;i<100;i++)
        {
                printf("Priority of High task2 %d\n",info.cprio);
        }

       int main(int argc, char* argv[])
{
        mlockall(MCL_CURRENT|MCL_FUTURE);

        rt_task_create(&task1, "Low Priority Task", 0, 3, 0);
        rt_task_create(&task2, "High Priority Task", 0, 98, 0);

        rt_task_start(&task1, &low_task, NULL);
        rt_task_start(&task2, &high_task, NULL);

        pause();

        rt_task_join(&task1);
        rt_task_join(&task2);

}













On 2/15/07, Jan Kiszka <jan.kiszka@domain.hid> wrote:
>
> Preetam Joshi wrote:
> > Hi,
> >
> > Do u mean to say that if i have created my tasks using native xenomai
> API's
> > like rt_task_create , then inside those tasks i will have to use posix
> skin
> > calls like pthread_setschedpolicy, etc...?
> >
> > Is that so.
>
> Nope. If you picked the native skin API, all scheduler setup for a RT
> task should be done through that interface.
>
> >
> > Cant i just have context switch between the tasks themselves say low
> > priority and a high priority task created by rt_task_create.
> >
> > Reason being i have created two tasks using the rt_task_create API and
> my
> > high priority task is runnning and my low priority task has slept, so as
> > soon as my low priority task has expired its sleep time and gets ready
> to
> > run,
> >
> > The low priority task preempts my high priority task and even its
> priority
> > gets raised to that of the high priority task and starts executing. The
> > higgh priority task gets suspended altogether amidst its running. Simply
> > baffled by the behavior?
>
> If you have found a weird behaviour of Xenomai, please post some
> as-small-as-possible demo code that exposes the issue. We will have a
> look at it.
>
> Jan
>
>
>