16 #define atomic_read(atomic) ((atomic)->value)               // 读取原子变量
17 #define atomic_set(atomic, val) (((atomic)->value) = (val)) // 设置原子变量的初始值
21     volatile long value;  member
33                  : "=m"(ato->value)  in atomic_add()
47                  : "=m"(ato->value)  in atomic_sub()
60                  : "=m"(ato->value)  in atomic_inc()
61                  : "m"(ato->value)  in atomic_inc()
73                  : "=m"(ato->value)  in atomic_dec()
74                  : "m"(ato->value)  in atomic_dec()
86                          : "=m"(ato->value)  in atomic_set_mask()
99                          : "=m"(ato->value)  in atomic_clear_mask()
107     bool success = arch_try_cmpxchg(&ato->value, &oldval, newval);  in atomic_cmpxchg()