eden/src/common/spin_lock.h

51 lines
1.3 KiB
C++

// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
// SPDX-License-Identifier: GPL-3.0-or-later
// SPDX-FileCopyrightText: Copyright 2020 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#pragma once
#ifdef _MSC_VER
#include <intrin.h>
#elif defined(ARCHITECTURE_x86_64)
#include <xmmintrin.h>
#endif
#include <atomic>
namespace Common {
/// @brief A lock similar to mutex that forces a thread to spin wait instead calling the
/// supervisor. Should be used on short sequences of code.
struct SpinLock {
SpinLock() noexcept = default;
SpinLock(const SpinLock&) noexcept = delete;
SpinLock& operator=(const SpinLock&) noexcept = delete;
SpinLock(SpinLock&&) noexcept = delete;
SpinLock& operator=(SpinLock&&) noexcept = delete;
inline void lock() noexcept {
while (lck.test_and_set(std::memory_order_acquire)) {
#if defined(ARCHITECTURE_x86_64)
_mm_pause();
#elif defined(ARCHITECTURE_arm64) && defined(_MSC_VER)
__yield();
#elif defined(ARCHITECTURE_arm64)
asm("yield");
#endif
}
}
inline void unlock() noexcept {
lck.clear(std::memory_order_release);
}
[[nodiscard]] inline bool try_lock() noexcept {
return !lck.test_and_set(std::memory_order_acquire);
}
std::atomic_flag lck = ATOMIC_FLAG_INIT;
};
} // namespace Common