std::atomic_thread_fence

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C++
 
原子操作库
类型
Original:
Types
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atomic（C++11）
atomic_is_lock_free（C++11）
功能
Original:
Functions
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atomic_store
atomic_store_explicit		（C++11）
（C++11）
atomic_load
atomic_load_explicit		（C++11）
（C++11）
atomic_exchange
atomic_exchange_explicit		（C++11）
（C++11）
atomic_compare_exchange_weak
atomic_compare_exchange_weak_explicit
atomic_compare_exchange_strong
atomic_compare_exchange_strong_explicit		（C++11）
（C++11）
（C++11）
（C++11）
atomic_fetch_add
atomic_fetch_add_explicit		（C++11）
（C++11）
atomic_fetch_sub
atomic_fetch_sub_explicit		（C++11）
（C++11）
atomic_fetch_and
atomic_fetch_and_explicit		（C++11）
（C++11）
atomic_fetch_or
atomic_fetch_or_explicit		（C++11）
（C++11）
atomic_fetch_xor
atomic_fetch_xor_explicit		（C++11）
（C++11）
原子标志
Original:
Atomic flags
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atomic_flag（C++11）
atomic_flag_test_and_set
atomic_flag_test_and_set_explicit		（C++11）
（C++11）
atomic_flag_clear
atomic_flag_clear_explicit		（C++11）
（C++11）
初始化
Original:
Initialization
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atomic_init（C++11）
ATOMIC_VAR_INIT（C++11）
ATOMIC_FLAG_INIT（C++11）
内存排序
Original:
Memory ordering
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memory_order（C++11）
kill_dependency（C++11）
atomic_thread_fence（C++11）
atomic_signal_fence（C++11）
 
Defined in header <atomic>
extern "C" void atomic_thread_fence( std::memory_order order );
 （C++11 起）
建立订货的非原子和轻松的指示，order的原子访问，内存同步，而没有相关的原子操作。例如，所有的非原子和宽松的原子店发生之前，std::memory_order_release围栏线程A将被同步的非原子和轻松的原子负载从std::memory_order_acquire围栏后，线程B在相同的位置.
Original:
Establishes memory synchronization ordering of non-atomic and relaxed atomic accesses, as instructed by order, without an associated atomic operation. For example, all non-atomic and relaxed atomic stores that happen before a std::memory_order_release fence in thread A will be synchronized with non-atomic and relaxed atomic loads from the same locations made in thread B after an std::memory_order_acquire fence.
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目录

[编辑] 参数

order -
这个围栏的记忆顺序执行
Original:
the memory ordering executed by this fence
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[编辑] 返回值

（无）
Original:
(none)
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[编辑] 例外

noexcept specification:  
noexcept
  （C++11 起）

[编辑] 的例子

Scan an array of mailboxes, and process only the ones intended for us, without unnecessary synchronization. 

const int num_mailboxes = 32;
std::atomic<int> mailbox[num_mailboxes];
 
// The writer threads update non-atomic shared data and then update mailbox[i] as follows
 std::atomic_store_explicit(&mailbox[i], std::memory_order_release);
 
// Reader thread needs to check all mailbox[i], but only needs to sync with one
 for (int i = 0; i < num_mailboxes; ++i) {
    if (std::atomic_load_explicit(&mailbox[i],  std::memory_order_relaxed) == my_id) {
        std::atomic_thread_fence(std::memory_order_acquire); // synchronize with just one writer
        do_work(i); // guaranteed to observe everything done in the writer thread before
                    // the atomic_store_explicit()
    }
 }


[编辑] 另请参阅

（C++11）
定义内存排序约束给定的原子操作
Original:
defines memory ordering constraints for the given atomic operation
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（的typedef） [edit]
（C++11）
围栏之间的线程和信号处理器，在同一个线程中执行
Original:
fence between a thread and a signal handler executed in the same thread
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（函数） [edit]
C documentation for atomic_thread_fence
来自“http://zh.cppreference.com/mwiki/index.php?title=cpp/atomic/atomic_thread_fence&oldid=27341”