src/dawn/common/Mutex.cpp

// Copyright 2023 The Dawn & Tint Authors
//
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// modification, are permitted provided that the following conditions are met:
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// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
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//    this software without specific prior written permission.
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#include "dawn/common/Mutex.h"

namespace dawn {
Mutex::~Mutex() = default;

void Mutex::Lock() {
#if defined(DAWN_ENABLE_ASSERTS)
    auto currentThread = std::this_thread::get_id();
    DAWN_ASSERT(mOwner.load(std::memory_order_acquire) != currentThread);
#endif  // DAWN_ENABLE_ASSERTS

    mNativeMutex.lock();

#if defined(DAWN_ENABLE_ASSERTS)
    mOwner.store(currentThread, std::memory_order_release);
#endif  // DAWN_ENABLE_ASSERTS
}
void Mutex::Unlock() {
#if defined(DAWN_ENABLE_ASSERTS)
    DAWN_ASSERT(IsLockedByCurrentThread());
    mOwner.store(std::thread::id(), std::memory_order_release);
#endif  // DAWN_ENABLE_ASSERTS

    mNativeMutex.unlock();
}

bool Mutex::IsLockedByCurrentThread() {
#if defined(DAWN_ENABLE_ASSERTS)
    return mOwner.load(std::memory_order_acquire) == std::this_thread::get_id();
#else
    // This is not supported.
    DAWN_CHECK(false);
#endif
}
}  // namespace dawn