spin lock with 9 threads waiting - who is next is random/mutex with 9 threads waiting, the first one in the queue will be the next

mutex-test.cpp

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include<iostream>
using namespace std;

static pthread_mutex_t foo_mutex;

void* get_maokeng(void* param)
{
        fprintf(stderr,"i like to paifang shit! %d\n",*(int*)param);
        pthread_mutex_lock(&foo_mutex);
        fprintf(stderr,"i first get maokeng! haha! %d\n",*(int*)param);
}

void* go_maokeng(void* param)
{
        fprintf(stderr,"i like to paifang shit! %d\n",*(int*)param);
        pthread_mutex_lock(&foo_mutex);
        fprintf(stderr,"i get maokeng! %d\n",*(int*)param);
        pthread_mutex_unlock(&foo_mutex);
};

int main()
{
        pthread_mutex_init(&foo_mutex, NULL);

        pthread_t* thread = (pthread_t*) malloc( 10 *sizeof( pthread_t));
        int token[10]={0,1,2,3,4,5,6,7,8,9};

        pthread_create(&thread[0],NULL,get_maokeng,&token[0]);
        sleep(1);
        for(int i=1;i<10;++i)
        {
                pthread_create(&thread[i],NULL,go_maokeng,&token[i]);
                sleep(1);
        }
        pthread_mutex_unlock(&foo_mutex);

        for(int i=0;i<10;++i)
        {
                pthread_join(thread[i],NULL);
        }
        free(thread);
        return 0;
}

spinlock-test.cpp

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include<iostream>
using namespace std;

static pthread_spinlock_t foo_spinlock;

void* get_maokeng(void* param)
{
        fprintf(stderr,"i like to paifang shit! %d\n",*(int*)param);
        pthread_spin_lock(&foo_spinlock);
        fprintf(stderr,"i first get maokeng! haha! %d\n",*(int*)param);
}

void* go_maokeng(void* param)
{
        fprintf(stderr,"i like to paifang shit! %d\n",*(int*)param);
        pthread_spin_lock(&foo_spinlock);
        fprintf(stderr,"i get maokeng! %d\n",*(int*)param);
        pthread_spin_unlock(&foo_spinlock);
};

int main()
{
        pthread_spin_init(&foo_spinlock, PTHREAD_PROCESS_PRIVATE);

        pthread_t* thread = (pthread_t*) malloc( 10 *sizeof( pthread_t));
        int token[10]={0,1,2,3,4,5,6,7,8,9};

        pthread_create(&thread[0],NULL,get_maokeng,&token[0]);
        sleep(1);
        for(int i=1;i<10;++i)
        {
                pthread_create(&thread[i],NULL,go_maokeng,&token[i]);
                sleep(1);
        }
        pthread_spin_unlock(&foo_spinlock);
        for(int i=0;i<10;++i)
        {
                pthread_join(thread[i],NULL);
        }
        free(thread);
        return 0;
}

一篇关于pthread mutex和spinlock分析的文章：http://www.searchtb.com/2011/01/pthreads-mutex-vs-pthread-spinlock.html