hi ,
i am using RH9-2.4.21 , NPTL version 0.29.
I am unable to set the policy and priority of any pthread while
creating it. after creating the thread , i am able to change its
scheduling policy and priority.
I am working as root.

I am writing a very simple program-- just creating a thread, assigning
it RR scheduling policy and priority =50.

In the created thread, I am checking its scheduling policy and priority

(using pthread_getschedparam ) and printing it.

It should print schedule policy RR and priority 50 ; but instead its
printing scheduling policy SCHED_OTHER and priority = 0.

following is my code :

#include
#include
#include
#include


void* CaptureThread()
{
int my_policy;
struct sched_param my_param;
int status;


status = pthread_getschedparam (pthread_self (), &my_policy,
&my_param);

printf ("# :thread_routine running at %s/%d\n",
(my_policy == SCHED_FIFO ? "FIFO"
: (my_policy == SCHED_RR ? "RR"
: (my_policy == SCHED_OTHER ? "OTHER"
: "unknown"))),
my_param.sched_priority);


}


pthread_t m_thread;


int main(void)
{


pthread_attr_t thread_attr;
struct sched_param thread_param;
pthread_attr_init(&thread_attr);


pthread_attr_setschedpolicy(&thread_attr, SCHED_RR);
/* setting the Sched policy */
thread_param.sched_priority = 50;

pthread_attr_setschedparam(&thread_attr, &thread_param);
/* setting the Priority */
pthread_create(&m_thread, &thread_attr, CaptureThread, NULL);
pthread_join(m_thread,NULL);

}


OUTPUT which i am getting :

# :thread_routine running at OTHER/0

Please guide me where i am making a mistake.

how to set the scheduling policy and priority of a thread while
creating it?

if I assign the policy and priority inside the created thread, its
working fine :

void* CaptureThread()
{
int my_policy;
struct sched_param my_param;
int status;
my_param.sched_priority = 50;
status = pthread_setschedparam (pthread_self (), SCHED_RR,
&my_param);
status = pthread_getschedparam (pthread_self (), &my_policy,
&my_param);
printf ("# :thread_routine running at %s/%d\n",
(my_policy == SCHED_FIFO ? "FIFO"
: (my_policy == SCHED_RR ? "RR"
: (my_policy == SCHED_OTHER ? "OTHER"
: "unknown"))),
my_param.sched_priority);


}

OUTPUT i am getting in this case :
# :thread_routine running at RR/50

where am i going wrong?


Thanks,
Jasdeep