SpinLock: Add releasePrematurely for early releases

include/spinLock.h

@@ -80,14 +80,25 @@ public:
 	{
 	public:
 		explicit Guard(SpinLock& lock)
-		: lock_(lock)
+		: lock_(lock), unlocked_(false)
 		{
 			lock_.acquire();
 		}
 
 		~Guard()
 		{
-			lock_.release();
+			if (!unlocked_) {
+				lock_.release();
+			}
+		}
+
+		void unlockPrematurely()
+		{
+			if (!unlocked_)
+			{
+				lock_.release();
+				unlocked_ = true;
+			}
 		}
 
 		// Non-copyable, non-movable
@@ -98,6 +109,7 @@ public:
 
 	private:
 		SpinLock& lock_;
+		bool unlocked_;
 	};
 
 private: