memory_order_release = release, memory_order_acq_rel = acq_rel, memory_order_seq_cst = seq_cst }; 所以你可以使用 memory_order::relaxed 代替 memory_order_relaxed,不过因为常量表达式的定义,在 C++ 20 使用 memory_order_relaxed 的代码仍然是合法的: inline constexpr memory_order memory_order_relax...
std::memory_order_release);// 发布数据}voidconsumer(){while(flag.load(std::memory_order_acquire...
其他线程中所有对M的release operation及其之前的写入都对当前线程从该acq_rel operation开始的操作可见,并且截止到该acq_rel operation的所有内存写入都对另外线程对M的acquire operation以及之后的内存操作可见。 1.6 memory_order_seq_cst memory_order_seq_cst 可以用于 load operation,release operation, read-modify...
std::memory_order_release)和thread_func2里flag.load(std::memory_order_acquire)来确保); 如果在运行时,事件2 Happen-Before事件1, 那基于flag这个原子变量的原子操作和内存顺序的实现无法确保事件2和事件1之间有Synchronize-With关系,
限于篇幅,这里只介绍memory_order_acquire(简称Acquire)和memory_order_release(简称Release)这两种内存顺序,后续再介绍C++的其他内存顺序。 下表给出了Acquire和Release的语义: 即,Acquire要求,针对某个读操作,该读操作之后的读操作或写操作,这两种情况下的指令顺序不能改变; Release要求,针对某个写操作,该写操作之前...
在这之后,别的cpu执行memory_order_acquire,都可以看到这个cpu所做的memory修改。 memory_order_acq_rel 是memory_order_acquire和memory_order_release的合并,这条语句前后的语句都不能被reorder。 memory_order_seq_cst 这是比memory_order_acq_rel更加严格的顺序保证,memory_order_seq_cst执行完毕后,所有其cpu都...
0** this wait loop must be a load-acquire such that we match the* store-release that clears ...
memory_order_relaxed, memory_order_consume, memory_order_acquire, memory_order_release, memory_order_acq_rel, memory_order_seq_cst }; 1. 2. 3. 4. 5. 6. 7. 8. 这六个值对应的内存访问序列化方式可分为三类内存访问模型,分别是:宽松的访问序列化模型、获取/释放语义模型和顺序一致性模型。按照...
读操作(memory_order_acquire memory_order_consume) 写操作(memory_order_release) 读-修改-写操作(memory_order_acq_rel memory_order_seq_cst) ps: 因为memory_order_relaxed没有定义同步和排序约束,所以它不适合这个分类。 2) 从访问控制的角度可以分为以下三种: ...
memory_order_release, memory_order_acq_rel, memory_order_seq_cst }; 上述6 中访存次序(内存序)分为 3 类,顺序一致性模型(std::memory_order_seq_cst),Acquire-Release 模型(std::memory_order_consume, std::memory_order_acquire, std::memory_order_release, std::memory_order_acq_rel,) (获取/释...