ryujinx-mirror/Ryujinx.HLE/HOS/Kernel/KThread.cs
gdkchan 00579927e4
Better process implementation (#491)
* Initial implementation of KProcess

* Some improvements to the memory manager, implement back guest stack trace printing

* Better GetInfo implementation, improve checking in some places with information from process capabilities

* Allow the cpu to read/write from the correct memory locations for accesses crossing a page boundary

* Change long -> ulong for address/size on memory related methods to avoid unnecessary casts

* Attempt at implementing ldr:ro with new KProcess

* Allow BSS with size 0 on ldr:ro

* Add checking for memory block slab heap usage, return errors if full, exit gracefully

* Use KMemoryBlockSize const from KMemoryManager

* Allow all methods to read from non-contiguous locations

* Fix for TransactParcelAuto

* Address PR feedback, additionally fix some small issues related to the KIP loader and implement SVCs GetProcessId, GetProcessList, GetSystemInfo, CreatePort and ManageNamedPort

* Fix wrong check for source pages count from page list on MapPhysicalMemory

* Fix some issues with UnloadNro on ldr:ro
2018-11-28 20:18:09 -02:00

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30 KiB
C#

using ChocolArm64;
using ChocolArm64.Memory;
using System;
using System.Collections.Generic;
using System.Linq;
using static Ryujinx.HLE.HOS.ErrorCode;
namespace Ryujinx.HLE.HOS.Kernel
{
class KThread : KSynchronizationObject, IKFutureSchedulerObject
{
public CpuThread Context { get; private set; }
public long AffinityMask { get; set; }
public long ThreadUid { get; private set; }
public long TotalTimeRunning { get; set; }
public KSynchronizationObject SignaledObj { get; set; }
public long CondVarAddress { get; set; }
private ulong Entrypoint;
public long MutexAddress { get; set; }
public KProcess Owner { get; private set; }
private ulong TlsAddress;
public long LastScheduledTime { get; set; }
public LinkedListNode<KThread>[] SiblingsPerCore { get; private set; }
public LinkedList<KThread> Withholder { get; set; }
public LinkedListNode<KThread> WithholderNode { get; set; }
public LinkedListNode<KThread> ProcessListNode { get; set; }
private LinkedList<KThread> MutexWaiters;
private LinkedListNode<KThread> MutexWaiterNode;
public KThread MutexOwner { get; private set; }
public int ThreadHandleForUserMutex { get; set; }
private ThreadSchedState ForcePauseFlags;
public int ObjSyncResult { get; set; }
public int DynamicPriority { get; set; }
public int CurrentCore { get; set; }
public int BasePriority { get; set; }
public int PreferredCore { get; set; }
private long AffinityMaskOverride;
private int PreferredCoreOverride;
private int AffinityOverrideCount;
public ThreadSchedState SchedFlags { get; private set; }
public bool ShallBeTerminated { get; private set; }
public bool SyncCancelled { get; set; }
public bool WaitingSync { get; set; }
private bool HasExited;
public bool WaitingInArbitration { get; set; }
private KScheduler Scheduler;
private KSchedulingData SchedulingData;
public long LastPc { get; set; }
public KThread(Horizon System) : base(System)
{
Scheduler = System.Scheduler;
SchedulingData = System.Scheduler.SchedulingData;
SiblingsPerCore = new LinkedListNode<KThread>[KScheduler.CpuCoresCount];
MutexWaiters = new LinkedList<KThread>();
}
public KernelResult Initialize(
ulong Entrypoint,
ulong ArgsPtr,
ulong StackTop,
int Priority,
int DefaultCpuCore,
KProcess Owner,
ThreadType Type = ThreadType.User)
{
if ((uint)Type > 3)
{
throw new ArgumentException($"Invalid thread type \"{Type}\".");
}
PreferredCore = DefaultCpuCore;
AffinityMask |= 1L << DefaultCpuCore;
SchedFlags = Type == ThreadType.Dummy
? ThreadSchedState.Running
: ThreadSchedState.None;
CurrentCore = PreferredCore;
DynamicPriority = Priority;
BasePriority = Priority;
ObjSyncResult = 0x7201;
this.Entrypoint = Entrypoint;
if (Type == ThreadType.User)
{
if (Owner.AllocateThreadLocalStorage(out TlsAddress) != KernelResult.Success)
{
return KernelResult.OutOfMemory;
}
MemoryHelper.FillWithZeros(Owner.CpuMemory, (long)TlsAddress, KTlsPageInfo.TlsEntrySize);
}
bool Is64Bits;
if (Owner != null)
{
this.Owner = Owner;
Owner.IncrementThreadCount();
Is64Bits = (Owner.MmuFlags & 1) != 0;
}
else
{
Is64Bits = true;
}
Context = new CpuThread(Owner.Translator, Owner.CpuMemory, (long)Entrypoint);
Context.ThreadState.X0 = ArgsPtr;
Context.ThreadState.X31 = StackTop;
Context.ThreadState.CntfrqEl0 = 19200000;
Context.ThreadState.Tpidr = (long)TlsAddress;
Owner.SubscribeThreadEventHandlers(Context);
Context.WorkFinished += ThreadFinishedHandler;
ThreadUid = System.GetThreadUid();
if (Owner != null)
{
Owner.AddThread(this);
if (Owner.IsPaused)
{
System.CriticalSection.Enter();
if (ShallBeTerminated || SchedFlags == ThreadSchedState.TerminationPending)
{
System.CriticalSection.Leave();
return KernelResult.Success;
}
ForcePauseFlags |= ThreadSchedState.ProcessPauseFlag;
CombineForcePauseFlags();
System.CriticalSection.Leave();
}
}
return KernelResult.Success;
}
public KernelResult Start()
{
if (!System.KernelInitialized)
{
System.CriticalSection.Enter();
if (!ShallBeTerminated && SchedFlags != ThreadSchedState.TerminationPending)
{
ForcePauseFlags |= ThreadSchedState.KernelInitPauseFlag;
CombineForcePauseFlags();
}
System.CriticalSection.Leave();
}
KernelResult Result = KernelResult.ThreadTerminating;
System.CriticalSection.Enter();
if (!ShallBeTerminated)
{
KThread CurrentThread = System.Scheduler.GetCurrentThread();
while (SchedFlags != ThreadSchedState.TerminationPending &&
CurrentThread.SchedFlags != ThreadSchedState.TerminationPending &&
!CurrentThread.ShallBeTerminated)
{
if ((SchedFlags & ThreadSchedState.LowMask) != ThreadSchedState.None)
{
Result = KernelResult.InvalidState;
break;
}
if (CurrentThread.ForcePauseFlags == ThreadSchedState.None)
{
if (Owner != null && ForcePauseFlags != ThreadSchedState.None)
{
CombineForcePauseFlags();
}
SetNewSchedFlags(ThreadSchedState.Running);
Result = KernelResult.Success;
break;
}
else
{
CurrentThread.CombineForcePauseFlags();
System.CriticalSection.Leave();
System.CriticalSection.Enter();
if (CurrentThread.ShallBeTerminated)
{
break;
}
}
}
}
System.CriticalSection.Leave();
return Result;
}
public void Exit()
{
System.CriticalSection.Enter();
ForcePauseFlags &= ~ThreadSchedState.ForcePauseMask;
ExitImpl();
System.CriticalSection.Leave();
}
private void ExitImpl()
{
System.CriticalSection.Enter();
SetNewSchedFlags(ThreadSchedState.TerminationPending);
HasExited = true;
Signal();
System.CriticalSection.Leave();
}
public long Sleep(long Timeout)
{
System.CriticalSection.Enter();
if (ShallBeTerminated || SchedFlags == ThreadSchedState.TerminationPending)
{
System.CriticalSection.Leave();
return MakeError(ErrorModule.Kernel, KernelErr.ThreadTerminating);
}
SetNewSchedFlags(ThreadSchedState.Paused);
if (Timeout > 0)
{
System.TimeManager.ScheduleFutureInvocation(this, Timeout);
}
System.CriticalSection.Leave();
if (Timeout > 0)
{
System.TimeManager.UnscheduleFutureInvocation(this);
}
return 0;
}
public void Yield()
{
System.CriticalSection.Enter();
if (SchedFlags != ThreadSchedState.Running)
{
System.CriticalSection.Leave();
System.Scheduler.ContextSwitch();
return;
}
if (DynamicPriority < KScheduler.PrioritiesCount)
{
//Move current thread to the end of the queue.
SchedulingData.Reschedule(DynamicPriority, CurrentCore, this);
}
Scheduler.ThreadReselectionRequested = true;
System.CriticalSection.Leave();
System.Scheduler.ContextSwitch();
}
public void YieldWithLoadBalancing()
{
System.CriticalSection.Enter();
if (SchedFlags != ThreadSchedState.Running)
{
System.CriticalSection.Leave();
System.Scheduler.ContextSwitch();
return;
}
int Prio = DynamicPriority;
int Core = CurrentCore;
KThread NextThreadOnCurrentQueue = null;
if (DynamicPriority < KScheduler.PrioritiesCount)
{
//Move current thread to the end of the queue.
SchedulingData.Reschedule(Prio, Core, this);
Func<KThread, bool> Predicate = x => x.DynamicPriority == Prio;
NextThreadOnCurrentQueue = SchedulingData.ScheduledThreads(Core).FirstOrDefault(Predicate);
}
IEnumerable<KThread> SuitableCandidates()
{
foreach (KThread Thread in SchedulingData.SuggestedThreads(Core))
{
int SrcCore = Thread.CurrentCore;
if (SrcCore >= 0)
{
KThread SelectedSrcCore = Scheduler.CoreContexts[SrcCore].SelectedThread;
if (SelectedSrcCore == Thread || ((SelectedSrcCore?.DynamicPriority ?? 2) < 2))
{
continue;
}
}
//If the candidate was scheduled after the current thread, then it's not worth it,
//unless the priority is higher than the current one.
if (NextThreadOnCurrentQueue.LastScheduledTime >= Thread.LastScheduledTime ||
NextThreadOnCurrentQueue.DynamicPriority < Thread.DynamicPriority)
{
yield return Thread;
}
}
}
KThread Dst = SuitableCandidates().FirstOrDefault(x => x.DynamicPriority <= Prio);
if (Dst != null)
{
SchedulingData.TransferToCore(Dst.DynamicPriority, Core, Dst);
Scheduler.ThreadReselectionRequested = true;
}
if (this != NextThreadOnCurrentQueue)
{
Scheduler.ThreadReselectionRequested = true;
}
System.CriticalSection.Leave();
System.Scheduler.ContextSwitch();
}
public void YieldAndWaitForLoadBalancing()
{
System.CriticalSection.Enter();
if (SchedFlags != ThreadSchedState.Running)
{
System.CriticalSection.Leave();
System.Scheduler.ContextSwitch();
return;
}
int Core = CurrentCore;
SchedulingData.TransferToCore(DynamicPriority, -1, this);
KThread SelectedThread = null;
if (!SchedulingData.ScheduledThreads(Core).Any())
{
foreach (KThread Thread in SchedulingData.SuggestedThreads(Core))
{
if (Thread.CurrentCore < 0)
{
continue;
}
KThread FirstCandidate = SchedulingData.ScheduledThreads(Thread.CurrentCore).FirstOrDefault();
if (FirstCandidate == Thread)
{
continue;
}
if (FirstCandidate == null || FirstCandidate.DynamicPriority >= 2)
{
SchedulingData.TransferToCore(Thread.DynamicPriority, Core, Thread);
SelectedThread = Thread;
}
break;
}
}
if (SelectedThread != this)
{
Scheduler.ThreadReselectionRequested = true;
}
System.CriticalSection.Leave();
System.Scheduler.ContextSwitch();
}
public void SetPriority(int Priority)
{
System.CriticalSection.Enter();
BasePriority = Priority;
UpdatePriorityInheritance();
System.CriticalSection.Leave();
}
public long SetActivity(bool Pause)
{
long Result = 0;
System.CriticalSection.Enter();
ThreadSchedState LowNibble = SchedFlags & ThreadSchedState.LowMask;
if (LowNibble != ThreadSchedState.Paused && LowNibble != ThreadSchedState.Running)
{
System.CriticalSection.Leave();
return MakeError(ErrorModule.Kernel, KernelErr.InvalidState);
}
System.CriticalSection.Enter();
if (!ShallBeTerminated && SchedFlags != ThreadSchedState.TerminationPending)
{
if (Pause)
{
//Pause, the force pause flag should be clear (thread is NOT paused).
if ((ForcePauseFlags & ThreadSchedState.ThreadPauseFlag) == 0)
{
ForcePauseFlags |= ThreadSchedState.ThreadPauseFlag;
CombineForcePauseFlags();
}
else
{
Result = MakeError(ErrorModule.Kernel, KernelErr.InvalidState);
}
}
else
{
//Unpause, the force pause flag should be set (thread is paused).
if ((ForcePauseFlags & ThreadSchedState.ThreadPauseFlag) != 0)
{
ThreadSchedState OldForcePauseFlags = ForcePauseFlags;
ForcePauseFlags &= ~ThreadSchedState.ThreadPauseFlag;
if ((OldForcePauseFlags & ~ThreadSchedState.ThreadPauseFlag) == ThreadSchedState.None)
{
ThreadSchedState OldSchedFlags = SchedFlags;
SchedFlags &= ThreadSchedState.LowMask;
AdjustScheduling(OldSchedFlags);
}
}
else
{
Result = MakeError(ErrorModule.Kernel, KernelErr.InvalidState);
}
}
}
System.CriticalSection.Leave();
System.CriticalSection.Leave();
return Result;
}
public void CancelSynchronization()
{
System.CriticalSection.Enter();
if ((SchedFlags & ThreadSchedState.LowMask) != ThreadSchedState.Paused || !WaitingSync)
{
SyncCancelled = true;
}
else if (Withholder != null)
{
Withholder.Remove(WithholderNode);
SetNewSchedFlags(ThreadSchedState.Running);
Withholder = null;
SyncCancelled = true;
}
else
{
SignaledObj = null;
ObjSyncResult = (int)MakeError(ErrorModule.Kernel, KernelErr.Cancelled);
SetNewSchedFlags(ThreadSchedState.Running);
SyncCancelled = false;
}
System.CriticalSection.Leave();
}
public KernelResult SetCoreAndAffinityMask(int NewCore, long NewAffinityMask)
{
System.CriticalSection.Enter();
bool UseOverride = AffinityOverrideCount != 0;
//The value -3 is "do not change the preferred core".
if (NewCore == -3)
{
NewCore = UseOverride ? PreferredCoreOverride : PreferredCore;
if ((NewAffinityMask & (1 << NewCore)) == 0)
{
System.CriticalSection.Leave();
return KernelResult.InvalidCombination;
}
}
if (UseOverride)
{
PreferredCoreOverride = NewCore;
AffinityMaskOverride = NewAffinityMask;
}
else
{
long OldAffinityMask = AffinityMask;
PreferredCore = NewCore;
AffinityMask = NewAffinityMask;
if (OldAffinityMask != NewAffinityMask)
{
int OldCore = CurrentCore;
if (CurrentCore >= 0 && ((AffinityMask >> CurrentCore) & 1) == 0)
{
if (PreferredCore < 0)
{
CurrentCore = HighestSetCore(AffinityMask);
}
else
{
CurrentCore = PreferredCore;
}
}
AdjustSchedulingForNewAffinity(OldAffinityMask, OldCore);
}
}
System.CriticalSection.Leave();
return KernelResult.Success;
}
private static int HighestSetCore(long Mask)
{
for (int Core = KScheduler.CpuCoresCount - 1; Core >= 0; Core--)
{
if (((Mask >> Core) & 1) != 0)
{
return Core;
}
}
return -1;
}
private void CombineForcePauseFlags()
{
ThreadSchedState OldFlags = SchedFlags;
ThreadSchedState LowNibble = SchedFlags & ThreadSchedState.LowMask;
SchedFlags = LowNibble | ForcePauseFlags;
AdjustScheduling(OldFlags);
}
private void SetNewSchedFlags(ThreadSchedState NewFlags)
{
System.CriticalSection.Enter();
ThreadSchedState OldFlags = SchedFlags;
SchedFlags = (OldFlags & ThreadSchedState.HighMask) | NewFlags;
if ((OldFlags & ThreadSchedState.LowMask) != NewFlags)
{
AdjustScheduling(OldFlags);
}
System.CriticalSection.Leave();
}
public void ReleaseAndResume()
{
System.CriticalSection.Enter();
if ((SchedFlags & ThreadSchedState.LowMask) == ThreadSchedState.Paused)
{
if (Withholder != null)
{
Withholder.Remove(WithholderNode);
SetNewSchedFlags(ThreadSchedState.Running);
Withholder = null;
}
else
{
SetNewSchedFlags(ThreadSchedState.Running);
}
}
System.CriticalSection.Leave();
}
public void Reschedule(ThreadSchedState NewFlags)
{
System.CriticalSection.Enter();
ThreadSchedState OldFlags = SchedFlags;
SchedFlags = (OldFlags & ThreadSchedState.HighMask) |
(NewFlags & ThreadSchedState.LowMask);
AdjustScheduling(OldFlags);
System.CriticalSection.Leave();
}
public void AddMutexWaiter(KThread Requester)
{
AddToMutexWaitersList(Requester);
Requester.MutexOwner = this;
UpdatePriorityInheritance();
}
public void RemoveMutexWaiter(KThread Thread)
{
if (Thread.MutexWaiterNode?.List != null)
{
MutexWaiters.Remove(Thread.MutexWaiterNode);
}
Thread.MutexOwner = null;
UpdatePriorityInheritance();
}
public KThread RelinquishMutex(long MutexAddress, out int Count)
{
Count = 0;
if (MutexWaiters.First == null)
{
return null;
}
KThread NewMutexOwner = null;
LinkedListNode<KThread> CurrentNode = MutexWaiters.First;
do
{
//Skip all threads that are not waiting for this mutex.
while (CurrentNode != null && CurrentNode.Value.MutexAddress != MutexAddress)
{
CurrentNode = CurrentNode.Next;
}
if (CurrentNode == null)
{
break;
}
LinkedListNode<KThread> NextNode = CurrentNode.Next;
MutexWaiters.Remove(CurrentNode);
CurrentNode.Value.MutexOwner = NewMutexOwner;
if (NewMutexOwner != null)
{
//New owner was already selected, re-insert on new owner list.
NewMutexOwner.AddToMutexWaitersList(CurrentNode.Value);
}
else
{
//New owner not selected yet, use current thread.
NewMutexOwner = CurrentNode.Value;
}
Count++;
CurrentNode = NextNode;
}
while (CurrentNode != null);
if (NewMutexOwner != null)
{
UpdatePriorityInheritance();
NewMutexOwner.UpdatePriorityInheritance();
}
return NewMutexOwner;
}
private void UpdatePriorityInheritance()
{
//If any of the threads waiting for the mutex has
//higher priority than the current thread, then
//the current thread inherits that priority.
int HighestPriority = BasePriority;
if (MutexWaiters.First != null)
{
int WaitingDynamicPriority = MutexWaiters.First.Value.DynamicPriority;
if (WaitingDynamicPriority < HighestPriority)
{
HighestPriority = WaitingDynamicPriority;
}
}
if (HighestPriority != DynamicPriority)
{
int OldPriority = DynamicPriority;
DynamicPriority = HighestPriority;
AdjustSchedulingForNewPriority(OldPriority);
if (MutexOwner != null)
{
//Remove and re-insert to ensure proper sorting based on new priority.
MutexOwner.MutexWaiters.Remove(MutexWaiterNode);
MutexOwner.AddToMutexWaitersList(this);
MutexOwner.UpdatePriorityInheritance();
}
}
}
private void AddToMutexWaitersList(KThread Thread)
{
LinkedListNode<KThread> NextPrio = MutexWaiters.First;
int CurrentPriority = Thread.DynamicPriority;
while (NextPrio != null && NextPrio.Value.DynamicPriority <= CurrentPriority)
{
NextPrio = NextPrio.Next;
}
if (NextPrio != null)
{
Thread.MutexWaiterNode = MutexWaiters.AddBefore(NextPrio, Thread);
}
else
{
Thread.MutexWaiterNode = MutexWaiters.AddLast(Thread);
}
}
private void AdjustScheduling(ThreadSchedState OldFlags)
{
if (OldFlags == SchedFlags)
{
return;
}
if (OldFlags == ThreadSchedState.Running)
{
//Was running, now it's stopped.
if (CurrentCore >= 0)
{
SchedulingData.Unschedule(DynamicPriority, CurrentCore, this);
}
for (int Core = 0; Core < KScheduler.CpuCoresCount; Core++)
{
if (Core != CurrentCore && ((AffinityMask >> Core) & 1) != 0)
{
SchedulingData.Unsuggest(DynamicPriority, Core, this);
}
}
}
else if (SchedFlags == ThreadSchedState.Running)
{
//Was stopped, now it's running.
if (CurrentCore >= 0)
{
SchedulingData.Schedule(DynamicPriority, CurrentCore, this);
}
for (int Core = 0; Core < KScheduler.CpuCoresCount; Core++)
{
if (Core != CurrentCore && ((AffinityMask >> Core) & 1) != 0)
{
SchedulingData.Suggest(DynamicPriority, Core, this);
}
}
}
Scheduler.ThreadReselectionRequested = true;
}
private void AdjustSchedulingForNewPriority(int OldPriority)
{
if (SchedFlags != ThreadSchedState.Running)
{
return;
}
//Remove thread from the old priority queues.
if (CurrentCore >= 0)
{
SchedulingData.Unschedule(OldPriority, CurrentCore, this);
}
for (int Core = 0; Core < KScheduler.CpuCoresCount; Core++)
{
if (Core != CurrentCore && ((AffinityMask >> Core) & 1) != 0)
{
SchedulingData.Unsuggest(OldPriority, Core, this);
}
}
//Add thread to the new priority queues.
KThread CurrentThread = Scheduler.GetCurrentThread();
if (CurrentCore >= 0)
{
if (CurrentThread == this)
{
SchedulingData.SchedulePrepend(DynamicPriority, CurrentCore, this);
}
else
{
SchedulingData.Schedule(DynamicPriority, CurrentCore, this);
}
}
for (int Core = 0; Core < KScheduler.CpuCoresCount; Core++)
{
if (Core != CurrentCore && ((AffinityMask >> Core) & 1) != 0)
{
SchedulingData.Suggest(DynamicPriority, Core, this);
}
}
Scheduler.ThreadReselectionRequested = true;
}
private void AdjustSchedulingForNewAffinity(long OldAffinityMask, int OldCore)
{
if (SchedFlags != ThreadSchedState.Running || DynamicPriority >= KScheduler.PrioritiesCount)
{
return;
}
//Remove from old queues.
for (int Core = 0; Core < KScheduler.CpuCoresCount; Core++)
{
if (((OldAffinityMask >> Core) & 1) != 0)
{
if (Core == OldCore)
{
SchedulingData.Unschedule(DynamicPriority, Core, this);
}
else
{
SchedulingData.Unsuggest(DynamicPriority, Core, this);
}
}
}
//Insert on new queues.
for (int Core = 0; Core < KScheduler.CpuCoresCount; Core++)
{
if (((AffinityMask >> Core) & 1) != 0)
{
if (Core == CurrentCore)
{
SchedulingData.Schedule(DynamicPriority, Core, this);
}
else
{
SchedulingData.Suggest(DynamicPriority, Core, this);
}
}
}
Scheduler.ThreadReselectionRequested = true;
}
public override bool IsSignaled()
{
return HasExited;
}
public void SetEntryArguments(long ArgsPtr, int ThreadHandle)
{
Context.ThreadState.X0 = (ulong)ArgsPtr;
Context.ThreadState.X1 = (ulong)ThreadHandle;
}
public void ClearExclusive()
{
Owner.CpuMemory.ClearExclusive(CurrentCore);
}
public void TimeUp()
{
ReleaseAndResume();
}
public void PrintGuestStackTrace()
{
Owner.Debugger.PrintGuestStackTrace(Context.ThreadState);
}
private void ThreadFinishedHandler(object sender, EventArgs e)
{
System.Scheduler.ExitThread(this);
Terminate();
System.Scheduler.RemoveThread(this);
}
public void Terminate()
{
Owner?.RemoveThread(this);
if (TlsAddress != 0 && Owner.FreeThreadLocalStorage(TlsAddress) != KernelResult.Success)
{
throw new InvalidOperationException("Unexpected failure freeing thread local storage.");
}
System.CriticalSection.Enter();
//Wake up all threads that may be waiting for a mutex being held
//by this thread.
foreach (KThread Thread in MutexWaiters)
{
Thread.MutexOwner = null;
Thread.PreferredCoreOverride = 0;
Thread.ObjSyncResult = 0xfa01;
Thread.ReleaseAndResume();
}
System.CriticalSection.Leave();
Owner?.DecrementThreadCountAndTerminateIfZero();
}
}
}