36 lines
770 B
Markdown
36 lines
770 B
Markdown
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# SpinLock::Lock
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```cpp
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void Lock()
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```
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获取自旋锁。如果锁已被其他线程持有，则使用忙等待（spin）持续轮询，直到获取到锁。
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**参数：** 无
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**返回：** 无
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**复杂度：** 平均 O(1)，最坏情况取决于竞争程度
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**注意：**
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- 适用于临界区极短（几个 CPU 指令）的场景，避免线程切换开销。
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- 在锁持有时间较长或多核竞争激烈时，会浪费大量 CPU 周期，此时应使用 Mutex。
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- 同一线程不可重复 Lock 同一个 SpinLock。
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**示例：**
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```cpp
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Threading::SpinLock spinLock;
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int64_t fastCounter = 0;
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void IncrementFast() {
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spinLock.Lock();
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++fastCounter;
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spinLock.Unlock();
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}
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```
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## 相关文档
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- [SpinLock 总览](spinlock.md) - 返回类总览
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