linux进程线程管理实验报告(8)

进程线程,死锁实验报告

3.1找到thread.c 的代码临界区，用临界区解决main_counter 与sum 不同步的问题。

3.2阅读下列代码，回答问题：

#include<stdio.h>

#include<sys/types.h>

#include<unistd.h>

#include<ctype.h>

#include<pthread.h>

#define LOOP_TIMES 1000

pthread_mutex_t mutex1=PTHREAD_MUTEX_INITIALIZER;

pthread_mutex_t mutex2=PTHREAD_MUTEX_INITIALIZER;

void* thread_worker(void *);

void critical_section(int threadd_num,int i);

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

int rtn,i;

pthread_t pthread_id=0;

rtn=pthread_create(&pthread_id,NULL,thread_worker,NULL);

if(rtn!=0){

printf("pthread_create ERROR!\n");

return -1;

}

for(i=0;i<LOOP_TIMES;i++){

pthread_mutex_lock(&mutex1);

pthread_mutex_lock(&mutex2);

critical_section(1,i);

pthread_mutex_unlock(&mutex2);

pthread_mutex_unlock(&mutex1);

}

pthread_mutex_destroy(&mutex1);

pthread_mutex_destroy(&mutex2);

return 0;

}

void *thread_worker(void* p){

int i;

for(i=0;i<LOOP_TIMES;i++){

pthread_mutex_lock(&mutex2);

pthread_mutex_lock(&mutex1);

critical_section(2,i);