147 lines
3.9 KiB
C++
147 lines
3.9 KiB
C++
/***
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Copyright (C) 2023 J Reece Wilson (a/k/a "Reece"). All rights reserved.
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File: FutexBarrier.hpp
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Date: 2023-09-20
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Author: Reece
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***/
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#pragma once
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#include "../WakeOnAddress.hpp"
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#include "../SpinTime.hpp"
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namespace Aurora::Threading::Waitables
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{
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struct FutexBarrier final
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{
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inline constexpr FutexBarrier(AuUInt32 uExpectThreads) :
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uAtomicSleeping(uExpectThreads),
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uAtomicState(0)
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{}
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AU_NO_COPY_NO_MOVE(FutexBarrier);
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inline bool Enter()
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{
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bool bTimeout {};
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return this->Park(bTimeout, true, 0);
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}
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inline AuPair<bool /* bSuccess */, bool /* bTimeOut */>
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EnterTimed(AuUInt64 uTimeoutAbsNS)
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{
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bool bTimeout {};
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bool bSuccess = this->Park(bTimeout, true, uTimeoutAbsNS);
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return AuMakePair(bSuccess, bTimeout);
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}
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inline AuPair<bool /* bSuccess */, bool /* bTimeOut */>
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EnterTimedEx(AuUInt64 uTimeoutAbsNS,
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AuVoidFunc callOnce)
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{
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bool bTimeout {}, bSuccess {};
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bSuccess = this->Park(bTimeout,
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true,
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uTimeoutAbsNS,
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callOnce);
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return AuMakePair(bSuccess, bTimeout);
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}
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inline bool TryEnter()
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{
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return this->TryEnterNoSpin();
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}
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inline bool TryWait()
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{
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return this->TryChkNoSpin();
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}
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inline bool Wait(AuUInt64 uTimeoutAbsNS = 0)
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{
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bool bTimeout {};
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(void)this->Park(bTimeout, false, uTimeoutAbsNS);
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return !bTimeout;
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}
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private:
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auline bool Park(bool &bTimedOut,
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bool bTakeOwnership,
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AuUInt64 uTimeoutAbsNS,
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AuVoidFunc callOnce = {})
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{
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static const AuUInt32 kRef { 0 };
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bTimedOut = false;
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if (bTakeOwnership)
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{
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if (!this->TryEnterNoSpin(callOnce))
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{
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return false;
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}
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}
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if (this->TryChkNoSpin())
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{
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return true;
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}
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(void)TryWaitOnAddress((const void *)&this->uAtomicState, &kRef, sizeof(kRef));
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while (!this->TryChkNoSpin())
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{
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if (!WaitOnAddressSteady((const void *)&this->uAtomicState, &kRef, sizeof(kRef), uTimeoutAbsNS))
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{
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if (this->TryChkNoSpin())
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{
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return true;
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}
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else
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{
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bTimedOut = true;
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return false;
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}
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}
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}
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return true;
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}
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auline bool TryEnterNoSpin(AuVoidFunc callOnce = {})
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{
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AuUInt32 uState;
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while ((uState = AuAtomicLoad(&this->uAtomicSleeping)) != 0)
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{
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if (AuAtomicCompareExchange(&this->uAtomicSleeping, uState - 1, uState) == uState)
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{
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if (uState == 1)
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{
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if (callOnce)
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{
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callOnce();
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}
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AuAtomicStore(&this->uAtomicState, 1u);
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WakeAllOnAddress((const void *)&this->uAtomicState);
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}
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return true;
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}
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}
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return false;
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}
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auline bool TryChkNoSpin()
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{
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return AuAtomicLoad(&this->uAtomicState) == 1;
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}
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public:
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AuAUInt32 uAtomicState {};
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AuAUInt32 uAtomicSleeping {};
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};
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} |