QNX 线程 调度策略 优先级 时钟频率 同步

/*
* barrier1.c
*/

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <time.h>
#include <pthread.h>
#include <sys/neutrino.h>
#include <timer.h>

pthread_barrier_t barrier; // barrier synchronization object

void *thread1 (void *not_used)
{

int policy;
struct sched_param param;
pthread_getschedparam(pthread_self(),&policy,&param);
if(policy == SCHED_OTHER)
printf("SCHED_OTHER 1 ");
if(policy == SCHED_RR);
printf("SCHED_RR 1 ");
if(policy==SCHED_FIFO)
printf("SCHED_FIFO 1 ");
if(policy==SCHED_SPORADIC)
printf("SCHED_SPARODIC 1 ");

setprio(0, 11); //设置线程优先级 越大优先级越高 0 代表当前进程
printf("thread1 priority is %d ",getprio(0));

time_t now;

time (&now);
printf ("thread1 starting at %s", ctime (&now));

// do the computation
// let's just do a sleep here...
while(1)
{
delay (100);
pthread_barrier_wait (&barrier);
// after this point, all three threads have completed.
time (&now);
printf ("barrier in thread1() done at %s", ctime (&now));
}
}

void *thread2 (void *not_used)
{
//查看线程的调度策略 默认为轮询
int policy;
struct sched_param param;
pthread_getschedparam(pthread_self(),&policy,&param);
if(policy == SCHED_OTHER)
printf("SCHED_OTHER 2 ");
if(policy == SCHED_RR);
printf("SCHED_RR 2 ");
if(policy==SCHED_FIFO)
printf("SCHED_FIFO 2 ");
if(policy==SCHED_SPORADIC)
printf("SCHED_SPARODIC 1 ");

setprio(0, 10); //设置线程优先级 越大优先级越高 0 代表当前进程
printf("thread2 priority is %d ",getprio(0));

time_t now;

time (&now);
printf ("thread2 starting at %s", ctime (&now));

// do the computation
// let's just do a sleep here...
while(1)
{
delay (200);
pthread_barrier_wait (&barrier);
// after this point, all three threads have completed.
time (&now);
printf ("barrier in thread2() done at %s", ctime (&now));
}
}

int main () // ignore arguments
{

pthread_t threadID1,threadID2;

setprio(0, 12); //设置线程优先级 越大优先级越高 0 代表当前进程
printf("Main priority is %d ",getprio(0));
//CPU 时钟频率
struct _clockperiod timep;
timep.nsec = 10*1000;
timep.fract = 0;
int ErrCode = 0;
ErrCode = ClockPeriod(CLOCK_REALTIME, &timep, NULL, 0);
if(ErrCode!=0)
{
printf( "Error: %s ", strerror(ErrCode));
}
/****************************************/
int ret = -1;
int timer_interrupt_id = -1;
ret = InitializeTimerInterrupt(0, 300, &timer_interrupt_id); //设置时钟中断，10ms
/*****************************************/
time_t now;

// create a barrier object with a count of 3
pthread_barrier_init (&barrier, NULL, 3);

// start up two threads, thread1 and thread2
pthread_create (&threadID1, 0, thread1, 0);
pthread_create (&threadID2, NULL, thread2, NULL);
// at this point, thread1 and thread2 are running

// now wait for completion
time (&now);
printf ("main() waiting for barrier at %s", ctime (&now));
while(1)
{
InterruptWait(0, NULL);
pthread_barrier_wait (&barrier);
// after this point, all three threads have completed.
time (&now);
printf ("barrier in main() done at %s", ctime (&now));
}
pthread_exit( NULL );
return (EXIT_SUCCESS);
}