public void ContextSwitch()
{
lock (CoreContexts)
{
if (MultiCoreScheduling)
{
int selectedCount = 0;
for (int core = 0; core < CpuCoresCount; core++)
{
KCoreContext coreContext = CoreContexts[core];
if (coreContext.ContextSwitchNeeded && (coreContext.CurrentThread?.Context.IsCurrentThread() ?? false))
{
coreContext.ContextSwitch();
}
if (coreContext.CurrentThread?.Context.IsCurrentThread() ?? false)
{
selectedCount++;
}
}
if (selectedCount == 0)
{
CoreManager.Reset(Thread.CurrentThread);
}
else if (selectedCount == 1)
{
CoreManager.Set(Thread.CurrentThread);
}
else
{
throw new InvalidOperationException("Thread scheduled in more than one core!");
}
}
else
{
KThread currentThread = CoreContexts[_currentCore].CurrentThread;
bool hasThreadExecuting = currentThread != null;
if (hasThreadExecuting)
{
// If this is not the thread that is currently executing, we need
// to request an interrupt to allow safely starting another thread.
if (!currentThread.Context.IsCurrentThread())
{
currentThread.Context.RequestInterrupt();
return;
}
CoreManager.Reset(currentThread.Context.Work);
}
// Advance current core and try picking a thread,
// keep advancing if it is null.
for (int core = 0; core < 4; core++)
{
_currentCore = (_currentCore + 1) % CpuCoresCount;
KCoreContext coreContext = CoreContexts[_currentCore];
coreContext.UpdateCurrentThread();
if (coreContext.CurrentThread != null)
{
CoreManager.Set(coreContext.CurrentThread.Context.Work);
coreContext.CurrentThread.Context.Execute();
break;
}
}
// If nothing was running before, then we are on a "external"
// HLE thread, we don't need to wait.
if (!hasThreadExecuting)
{
return;
}
}
}
CoreManager.Wait(Thread.CurrentThread);
}
public void Leave()
{
if (_recursionCount == 0)
{
return;
}
bool doContextSwitch = false;
if (--_recursionCount == 0)
{
if (_context.Scheduler.ThreadReselectionRequested)
{
_context.Scheduler.SelectThreads();
}
Monitor.Exit(LockObj);
if (_context.Scheduler.MultiCoreScheduling)
{
lock (_context.Scheduler.CoreContexts)
{
for (int core = 0; core < KScheduler.CpuCoresCount; core++)
{
KCoreContext coreContext = _context.Scheduler.CoreContexts[core];
if (coreContext.ContextSwitchNeeded)
{
KThread currentThread = coreContext.CurrentThread;
if (currentThread == null)
{
// Nothing is running, we can perform the context switch immediately.
coreContext.ContextSwitch();
}
else if (currentThread.IsCurrentHostThread())
{
// Thread running on the current core, context switch will block.
doContextSwitch = true;
}
else
{
// Thread running on another core, request a interrupt.
currentThread.Context.RequestInterrupt();
}
}
}
}
}
else
{
doContextSwitch = true;
}
}
else
{
Monitor.Exit(LockObj);
}
if (doContextSwitch)
{
_context.Scheduler.ContextSwitch();
}
}