1 #define _GNU_SOURCE
2 #include <unistd.h>
3 #include <stdio.h>
4 #include <stdlib.h>
5 #include <string.h>
6 #include <time.h>
7 #include <linux/unistd.h>
8 #include <linux/kernel.h>
9 #include <linux/types.h>
0 #include <sys/syscall.h>
1 #include <pthread.h>
2
3 #define gettid() syscall(__NR_gettid)
4
5 #define SCHED_DEADLINE  6
6
7 /* XXX use the proper syscall numbers */
8 #ifdef __x86_64__
9 #define __NR_sched_setattr      314
0 #define __NR_sched_getattr      315
1 #endif
2 #ifdef __i386__
3 #define __NR_sched_setattr      351
4 #define __NR_sched_getattr      352
5 #endif
6 #ifdef __arm__
7 #define __NR_sched_setattr      380
8 #define __NR_sched_getattr      381
9 #endif
0
1 static volatile int done;
2
3 struct sched_attr {
4     __u32 size;
5
6     __u32 sched_policy;
7     __u64 sched_flags;
8
9     /* SCHED_NORMAL, SCHED_BATCH */
0     __s32 sched_nice;
1
2     /* SCHED_FIFO, SCHED_RR */
3     __u32 sched_priority;
4
5     /* SCHED_DEADLINE (nsec) */
6     __u64 sched_runtime;
7     __u64 sched_deadline;
8     __u64 sched_period;
9 };
0
1 int sched_setattr(pid_t pid,
2     const struct sched_attr *attr,
3     unsigned int flags)
4 {
5     return syscall(__NR_sched_setattr,
6         pid, attr, flags);
7 }
8
9 int sched_getattr(pid_t pid,
0     struct sched_attr *attr,
1     unsigned int size,
2     unsigned int flags)
3 {
4     return syscall(__NR_sched_getattr,
5         pid, attr, size, flags);
6 }
7
8 void *run_deadline(void *data)
9 {
0     struct sched_attr attr;
1     int x = 0, ret;
2     unsigned int flags = 0;
3
4     printf("deadline thread start %ld\n",
5         gettid());
6
7     attr.size = sizeof(attr);
8     attr.sched_flags = 0;
9     attr.sched_nice = 0;
0     attr.sched_priority = 0;
1
2     /* creates a 10ms/30ms reservation */
3     attr.sched_policy = SCHED_DEADLINE;
4     attr.sched_runtime = 10 * 1000 * 1000;
5     attr.sched_period  = 30 * 1000 * 1000;
6     attr.sched_deadline= 30 * 1000 * 1000;
7
8     ret = sched_setattr(0, &attr, flags);
9     if (ret < 0) {
0         done = 0;
1         perror("sched_setattr");
2         exit(-1);
3     }
4
5     while (!done) {
6         x++;
7     }
8     return NULL;
9 }
0
1 int main (int argc, char **argv)
2 {
3     pthread_t thread;
4
5     printf("main thread [%ld]\n", gettid());
6     pthread_create(&thread, NULL, run_deadline, NULL);
7     sleep(10);
8     done = 1;
9     pthread_join(thread, NULL);
0     printf("main dies [%ld]\n", gettid());
1     return 0;
2 }