求教，linux下进程优先级

wy200747055

程序如下：
#include<stdio.h>
#include<pthread.h>
#include<sched.h>

void *child_thread(void *arg)
{
int policy;
int max_priority,min_priority;
struct sched_param param;
pthread_attr_t attr;

pthread_attr_init(&attr);
pthread_attr_setinheritsched(&attr,PTHREAD_EXPLICIT_SCHED);
pthread_attr_getinheritsched(&attr,&policy);
if(policy==PTHREAD_EXPLICIT_SCHED)
    printf(“InheritschedTHREAD_EXPLICIT_SCHED\n”);
if(policy==PTHREAD_INHERIT_SCHED)
    printf(“InheritschedTHREAD_INHERIT_SCHED\n”);

pthread_attr_setschedpolicy(&attr,SCHED_RR);
pthread_attr_getschedpolicy(&attr,&policy);
if(policy==SCHED_FIFO)
    printf(“Schedpolicy:SCHED_FIFO\n”);
if(policy==SCHED_RR)
    printf(“Schedpolicy:SCHED_RR\n”);
if(policy==SCHED_OTHER)
    printf(“Schedpolicy:SCHED_OTHER\n”);

sched_get_priority_max(max_priority);
sched_get_priority_min(min_priority);
printf(“Maxpriority:%u\n”,max_priority);
printf(“Minpriority:%u\n”,min_priority);

param.sched_priority=max_priority;
pthread_attr_setschedparam(&attr,&param);
printf(“sched_priority:%u\n”,param.sched_priority);
pthread_attr_destroy(&attr);
}

int main(int argc,char *argv[ ])
{
pthread_t child_thread_id;

pthread_create(&child_thread_id,NULL,child_thread,NULL);
pthread_join(child_thread_id,NULL);
}

运行结果如下:


程序中红色部分为我获取进程最大优先级和最小优先级部分。但是结果中显示的最大优先级比最小优先加的值小，这在linux下是正确的。但是，我查看的资料上说的linux的优先级的值是-20到19之间，为什么我运行的结果中优先级的值都这么大呢，完全不在-20到19之间呢？
求大牛，求指教~

donglongchao

1. sched_get_priority_max(max_priority);
   
2. sched_get_priority_min(min_priority);

复制代码

这两个函数用错了。

wy200747055

怎么用错了，那正确的应该怎么用？

chen0610

sched_get_priority_max输入参数是调度策略SCHED_OTHER等