From 60fe26ff2f49c72dfee87d96fb35f68eaeb02a6f Mon Sep 17 00:00:00 2001
From: Gregory Hainaut <gregory.hainaut@gmail.com>
Date: Mon, 22 Feb 2016 19:55:39 +0100
Subject: [PATCH] common:threading: Port NonblockingMutex to std::atomic_flag

---
 common/include/Utilities/Threading.h | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/common/include/Utilities/Threading.h b/common/include/Utilities/Threading.h
index be0244db50..b50fa2e2d8 100644
--- a/common/include/Utilities/Threading.h
+++ b/common/include/Utilities/Threading.h
@@ -222,23 +222,24 @@ namespace Threading
 	class NonblockingMutex
 	{
 	protected:
-		volatile int val;
+		std::atomic_flag val;
 
 	public:
-		NonblockingMutex() : val( false ) {}
+		NonblockingMutex() { val.clear(); }
 		virtual ~NonblockingMutex() throw() {}
 
 		bool TryAcquire() throw()
 		{
-			return !AtomicExchange( val, true );
+			return !val.test_and_set();
 		}
 
+		// Can be done with a TryAcquire/Release but it is likely better to do it outside of the object
 		bool IsLocked()
-		{ return !!val; }
+		{ pxAssertMsg(0, "IsLocked isn't supported for NonblockingMutex"); return false; }
 
 		void Release()
 		{
-			AtomicExchange( val, false );
+			val.clear();
 		}
 	};