对64位长整形赋值为原子操作

来源：互联网发布：百度贴吧加载数据失败编辑：程序博客网时间：2024/05/18 03:26

测试平台：sparc（Solaris ）、x86（Solaris）、x86（Linux）

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <unistd.h>
#include <pthread.h>

#define G_THREAD_NUM 5

void* add_main(void* arg);
void* del_main(void* arg);
void print_glo();

unsigned long long      g_uint64_n;
unsigned long long      g_tmp1 = 0;
unsigned long long      g_tmp2 = 0xffffffffffffffffLL;

void* write_main(void* arg)
{
        unsigned long long      tmp = g_tmp1;
        while(1){
                g_uint64_n = tmp;
        }
        return NULL;
}

void* read_main(void* arg)
{
        while(1){
                g_uint64_n = g_tmp2;
        }
        return NULL;
}

void print_glo()
{
        unsigned long long tmp;
        unsigned int l;
        unsigned int r;
        while(1){
                tmp = g_uint64_n;
                l = tmp >> 32;
                r = tmp;
                if(l != r){
                        printf("left:%x,right:%x\n", l, r);
                        printf("assert:%llx\n", tmp);
                }
        }
}

int main()
{
int i;

pthread_t add[G_THREAD_NUM];
pthread_t del[G_THREAD_NUM];

        for(i=0; i<G_THREAD_NUM; i++)
                pthread_create(&add[i], NULL, write_main, NULL);
        for(i=0; i<G_THREAD_NUM; i++)
                pthread_create(&del[i], NULL, read_main, NULL);
        print_glo();
        return 0;
}