godot/core/spin_lock.h

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/*  spin_lock.h                                                          */
/*************************************************************************/
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/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
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#ifndef SPIN_LOCK_H
#define SPIN_LOCK_H

#include "core/typedefs.h"

#include <atomic>

class SpinLock {
	std::atomic_flag locked = ATOMIC_FLAG_INIT;

public:
	_ALWAYS_INLINE_ void lock() {
		while (locked.test_and_set(std::memory_order_acquire)) {
			;
		}
	}
	_ALWAYS_INLINE_ void unlock() {
		locked.clear(std::memory_order_release);
	}
};
#endif // SPIN_LOCK_H