无锁编程

 1 #ifndef MUTEX_CLASS_H
 2 #define MUTEX_CLASS_H
 3 
 4 class mutex_class
 5 {
 6 public:
 7     mutex_class();
 8     void lock();
 9     void unlock();
10 
11 private:
12     //以下为使用，和一般的锁差不多
13     int MUTEX_VALUE;
14 };
15 
16 #endif // MUTEX_CLASS_H

 1 #include "mutex_class.h"
 2 #include <sched.h>
 3 
 4 #define LOCK_VALUE  0
 5 #define   UNLOCK_VALUE 1
 6 //nt MUTEX_VALUE  = LOCK_VALUE;
 7 #define FREE_LOCK(MUTEX_VALUE_LOCK) 8     while (!(__sync_bool_compare_and_swap ( 9               &MUTEX_VALUE_LOCK,LOCK_VALUE, 10               UNLOCK_VALUE) )) 11                  sched_yield();
12 
13  #define FREE_UNLOCK(MUTEX_VALUE_LOCK)14          __sync_bool_compare_and_swap (&MUTEX_VALUE_LOCK, UNLOCK_VALUE, LOCK_VALUE);
15 
16 
17 
18 
19 mutex_class::mutex_class()
20 {
21     MUTEX_VALUE = LOCK_VALUE;
22 }
23 
24 void mutex_class::lock()
25 {
26     FREE_LOCK(MUTEX_VALUE)
27 }
28 
29 void mutex_class::unlock()
30 {
31     FREE_UNLOCK(MUTEX_VALUE)
32 }