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+====== SpinLock implementation in C++ ======
+{{tag>cpp dev}}
+Since I read the book **Game Engine Architecture** I was looking for a way to implement a simple **SpinLock** in C++. And actually it turns out this is (almost) readily available from boost.
+====== ======
+I used the following reference pages:
+  * [[https://jiafei427.wordpress.com/2016/08/24/spinlock-v-s-mutex-v-s-atomics/|This page clearly shows that you don't want to use mutexes in many situations]].
+  * [[https://www.boost.org/doc/libs/1_54_0/doc/html/atomic/usage_examples.html#boost_atomic.usage_examples.example_spinlock|The official boost spinlock implementation template]]
+  * [[https://stackoverflow.com/questions/19742993/implementing-a-spinlock-in-boost-example-needed|The source I used for my own implementation]].
+And in the end, if will fit in a single simple header file: <sxh cpp>#ifndef NV_SPINLOCK_H_
+#define NV_SPINLOCK_H_
+#include <boost/atomic.hpp>
+#include <boost/thread.hpp>
+namespace nv {
+class SpinLock
+{
+    boost::atomic_flag flag; // it differs from std::atomic_flag a bit -
+                             // does not require ATOMIC_FLAG_INIT
+public:
+    void lock()
+    {
+        while( flag.test_and_set(boost::memory_order_acquire) )
+            ;
+    }
+    bool try_lock()
+    {
+        return !flag.test_and_set(boost::memory_order_acquire);
+    }
+    void unlock()
+    {
+        flag.clear(boost::memory_order_release);
+    }
+};
+typedef boost::lock_guard<SpinLock> SpinLockGuard;
+};
+#endif</sxh>