create thread的时候发生core dump

 1 #include <stdio.h>
 2 #include <unistd.h>
 3 #include <stdlib.h>
 4 #include <pthread.h>
 5 #define THREAD_COUNT 12
 6 
 7 void show_thread_policy(int threadno){
 8         int policy;
 9         struct sched_param param;
10         pthread_getschedparam(pthread_self(), &policy, &param);
11         switch(policy){
12         case SCHED_OTHER:
13                 printf("SCHED_OTHER %d
", threadno);
14                 break;
15         case SCHED_RR:
16                 printf("SCHED_RR %d
", threadno);
17                 break;
18         case SCHED_FIFO:
19                 printf("SCHED_FIFO %d
", threadno);
20                 break;
21         default:
22                 printf("UNKNOWN
");
23         }
24 }
25 
26 void *thread(void *arg){
27         int i,j;
28         long threadno = (long)arg;
29         printf("thread %d start 
", threadno);
30         printf("thread ------------------------------0
");
31         sleep(1);
32         printf("---------1---------------
");
33         show_thread_policy(threadno);
34         printf("---------2---------------
");
35         for(int i=0;i<10;i++){
36                 printf("---------3---------------
");
37                 for(j=0;j<10000000;j++){
38 
39                 }
40 
41                 printf("thread %d
", threadno);
42         }
43 
44         printf("thread %d exit
", threadno);
45         return NULL;
46 }
47 
48 int main(int argc, char *argv[]){
49         long i;
50         pthread_attr_t attr[THREAD_COUNT];
51         pthread_t pth[THREAD_COUNT];
52         struct sched_param param;
53         for(i=0;i<THREAD_COUNT;++i){
54                 pthread_attr_init(&attr[i]);
55                 for(i=0;i<THREAD_COUNT/2;++i){
56                         param.sched_priority = 10;
57                         pthread_attr_setschedpolicy(&attr[i], SCHED_FIFO);
58                         pthread_attr_setschedparam(&attr[i], &param);
59                         pthread_attr_setinheritsched(&attr[i], PTHREAD_EXPLICIT_SCHED);
60                 }
61 
62                 for(i=THREAD_COUNT/2;i<THREAD_COUNT;++i){
63                         param.sched_priority = 20;
64                         pthread_attr_setschedpolicy(&attr[i], SCHED_FIFO);
65                         pthread_attr_setschedparam(&attr[i], &param);
66                         pthread_attr_setinheritsched(&attr[i], PTHREAD_EXPLICIT_SCHED);
67                 }
68 
69                 for(i=0;i<THREAD_COUNT;++i){
70                         pthread_create(&pth[i], &attr[i], thread, (void *)i);
71                         printf("--------------------create thread %d------------
", i);
72                 }
73 
74                 for(i=0;i<THREAD_COUNT;++i){
75                         pthread_join(pth[i], NULL);
76                 }
77 
78                 for(i=0;i<THREAD_COUNT;++i){
79                         pthread_attr_destroy(&attr[i]);
80                 }
81 
82                 return 0;
83         }
84 }

编译之后执行的结果如下：

[root@Alston C++]# ./thread_2.exe
thread 0 start
thread ------------------------------0
--------------------create thread 0------------
--------------------create thread 1------------
--------------------create thread 2------------
--------------------create thread 3------------
Segmentation fault (core dumped)

目前还没调查出来原因。