From e2059380de131dacabcfa876368d7aab913857cb Mon Sep 17 00:00:00 2001
From: Sergey Sharybin <sergey.vfx@gmail.com>
Date: Mon, 22 Feb 2016 16:43:48 +0100
Subject: [PATCH] Cycles: Add easy to use spin lock primitive

Currently unused, but will be handy for an upcoming changes.

It'll also be nice to be able to do scoped_lock() for both
Mutex and Spin, but currently it's not really easy to do,
need some changes in typedefs and such, will happen as a
separate commit.
---
 intern/cycles/util/util_thread.h | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/intern/cycles/util/util_thread.h b/intern/cycles/util/util_thread.h
index 9c19235d41d..d9cf452be13 100644
--- a/intern/cycles/util/util_thread.h
+++ b/intern/cycles/util/util_thread.h
@@ -81,6 +81,29 @@ protected:
 	bool joined;
 };
 
+/* Own wrapper around pthread's spin lock to make it's use easier. */
+
+class thread_spin_lock {
+public:
+	inline thread_spin_lock() {
+		pthread_spin_init(&spin_, 0);
+	}
+
+	inline ~thread_spin_lock() {
+		pthread_spin_destroy(&spin_);
+	}
+
+	inline void lock() {
+		pthread_spin_lock(&spin_);
+	}
+
+	inline void unlock() {
+		pthread_spin_unlock(&spin_);
+	}
+protected:
+	pthread_spinlock_t spin_;
+};
+
 CCL_NAMESPACE_END
 
 #endif /* __UTIL_THREAD_H__ */