843 lines
34 KiB
C#
843 lines
34 KiB
C#
////////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// Microsoft Research Singularity
|
|
//
|
|
// Copyright (c) Microsoft Corporation. All rights reserved.
|
|
//
|
|
// File: LaxityScheduler.cs
|
|
//
|
|
// Note:
|
|
//
|
|
|
|
using System;
|
|
using System.Collections;
|
|
using System.Diagnostics;
|
|
using System.Threading;
|
|
using Microsoft.Singularity;
|
|
using Microsoft.Singularity.Scheduling;
|
|
|
|
namespace Microsoft.Singularity.Scheduling
|
|
{
|
|
#if !SIMULATOR
|
|
public class SystemScheduler
|
|
{
|
|
static public void RegisterScheduler()
|
|
{
|
|
Laxity.LaxityScheduler.RegisterScheduler();
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
namespace Microsoft.Singularity.Scheduling.Laxity
|
|
{
|
|
/// <summary>
|
|
/// Summary description for LaxityScheduler.
|
|
/// </summary>
|
|
public class LaxityScheduler : ICpuScheduler
|
|
{
|
|
public static readonly TimeSpan ContextSwitch = new TimeSpan(200);
|
|
public static readonly TimeSpan MinSlice = new TimeSpan(10 * ContextSwitch.Ticks);
|
|
public static readonly TimeSpan AFewSlice = new TimeSpan(3 * MinSlice.Ticks);
|
|
public static readonly TimeSpan RobinSlice = new TimeSpan(10 * TimeSpan.TicksPerMillisecond);
|
|
|
|
static public void RegisterScheduler()
|
|
{
|
|
CpuResource.RegisterSystemScheduler(new LaxityScheduler());
|
|
}
|
|
|
|
public override ISchedulerProcessor CreateSchedulerProcessor(Processor processor)
|
|
{
|
|
return new LaxityProcessor(processor);
|
|
}
|
|
|
|
public override ISchedulerThread CreateSchedulerThread(Thread thread)
|
|
{
|
|
return new LaxityThread(thread);
|
|
}
|
|
|
|
public override ISchedulerActivity CreateSchedulerActivity()
|
|
{
|
|
return new LaxityActivity();
|
|
}
|
|
|
|
public override ISchedulerCpuReservation ReserveCpu(ISchedulerActivity activity, CpuResourceAmount amount, TimeSpan period)
|
|
{
|
|
return null;
|
|
}
|
|
|
|
public bool ReserveRecurringCpu(Activity activity, ref TimeSpan amount, ref TimeSpan period)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
public override bool ShouldReschedule()
|
|
{
|
|
LaxityThread currentThread = GetCurrentThread();
|
|
if (Scheduler.TimerInterruptedFlag && currentThread != null) {
|
|
//SchedulerClock.CheckInterrupt();
|
|
}
|
|
|
|
if (currentThread == null || Scheduler.YieldFlag || currentThread.EnclosingThread.IsWaiting() || currentThread.EnclosingThread.IsStopped()) {
|
|
Reschedule();
|
|
}
|
|
return NeedToReschedule || Scheduler.TimerInterruptedFlag;
|
|
// || timer should have fired but didn't?
|
|
}
|
|
|
|
// DI -- this is somehow similar to EnableInterrupts
|
|
public override bool NextThread(out Thread nextThread)
|
|
{
|
|
Debug.Assert(!Processor.InterruptsDisabled());
|
|
bool iflag = Processor.DisableInterrupts();
|
|
bool halted = false;
|
|
LaxityThread currentThread = GetCurrentThread();
|
|
|
|
SchedulerClock.CheckInterrupt();
|
|
if (ShouldReschedule()) {
|
|
//Debug.Print("Calling RescheduleInterrupt()\n");
|
|
halted = RescheduleInterrupt(); //TODO: RescheduleInterrupt returns true if the processor needs to be halted.
|
|
currentThread = GetCurrentThread();
|
|
}
|
|
else {
|
|
//Debug.Print("No call to RescheduleInterrupt()\n");
|
|
}
|
|
|
|
if (currentThread != null) {
|
|
nextThread = currentThread.EnclosingThread;
|
|
}
|
|
else {
|
|
Debug.Assert(halted);
|
|
nextThread = null;
|
|
}
|
|
|
|
((LaxityProcessor)Processor.CurrentProcessor.SchedulerProcessor).NeedToReschedule = false;
|
|
// printf("-------------------------currentThread-Id %d\n", currentThread.Id);
|
|
//return currentThread;
|
|
Processor.RestoreInterrupts(iflag);
|
|
return halted;
|
|
}
|
|
//public static void Yield();
|
|
#region Constants
|
|
|
|
// Maximum Scheduling Period is 1 sec (i.e. in 100s of nanoseconds).
|
|
static readonly TimeSpan AmountCpu = CpuResource.MaxPeriod; //(MaxPeriod * 100); //TODO: TICKS vs. TIME_SPAN vs DATE_TIME
|
|
|
|
#endregion
|
|
|
|
#region Static data members
|
|
static LaxityActivity CircularActivityList = null;
|
|
/// <summary>
|
|
/// This must ALWAYS (when lock not held) point to a current resource
|
|
/// container in the queue.
|
|
/// </summary>
|
|
static internal LaxityActivity NextActivity;
|
|
|
|
|
|
//moved to be processor specific
|
|
//static LaxityActivity LaxityActivityNext = null;
|
|
//static LaxityActivity LaxityActivityCurrent = null; // activity currently executing from
|
|
|
|
private static OneShotReservation ReservationFreePool;
|
|
private static TimeSpan IdleTime = new TimeSpan(0);
|
|
private static bool Idle
|
|
{
|
|
get { return GetCurrentProcessor().Idle; }
|
|
}
|
|
|
|
//moved to be processor specific
|
|
//static LaxityThread CurrentThreadGlobal = null;
|
|
//static TimeSpan LaxitySliceLeft = LaxityScheduler.LaxitySlice; //new TimeSpan(0); // the round robin list, if any, and its CPU slice
|
|
//public static DateTime SchedulingTime;
|
|
//static bool NeedToReschedule = false;
|
|
|
|
public static TimeSpan LA_Time = LaxityScheduler.MinSlice;
|
|
|
|
public static DateTime SchedulingTime
|
|
{
|
|
get {
|
|
return ((LaxityProcessor)Processor.CurrentProcessor.SchedulerProcessor).SchedulingTime;
|
|
}
|
|
}
|
|
|
|
public static bool NeedToReschedule
|
|
{
|
|
get {
|
|
return ((LaxityProcessor)Processor.CurrentProcessor.SchedulerProcessor).NeedToReschedule;
|
|
}
|
|
}
|
|
|
|
#endregion
|
|
|
|
public LaxityScheduler()
|
|
{
|
|
}
|
|
|
|
public override void Initialize()
|
|
{
|
|
LaxityScheduler.InitializeScheduler();
|
|
}
|
|
|
|
public static void InitializeScheduler()
|
|
{ //TODO: Should all the null's be added in here?
|
|
for (int i = 0; i < Processor.processorTable.Length; i++) {
|
|
((LaxityProcessor)Processor.processorTable[i].SchedulerProcessor).SchedulingTime = SystemClock.GetKernelTime();
|
|
}
|
|
//
|
|
// TimeSpan currentSliceLeft = LaxitySliceLeft;
|
|
bool iflag = Processor.DisableInterrupts();
|
|
SchedulerClock.SetNextInterrupt(SchedulingTime + LaxityScheduler.RobinSlice);
|
|
Processor.RestoreInterrupts(iflag);
|
|
}
|
|
|
|
#region ISystemScheduler Members
|
|
|
|
public override void BeginDelayedConstraint(Hashtable resourceEstimates, TimeSpan relativeDeadline, ISchedulerTask taskToEnd, out ISchedulerTask schedulerTask)
|
|
{
|
|
TimeConstraint timeConstraint = new TimeConstraint();
|
|
timeConstraint.Estimate = CpuResource.Provider().CpuToTime((CpuResourceAmount)resourceEstimates[CpuResource.Provider().ResourceString]);
|
|
timeConstraint.Start = new DateTime(0); //Start now.
|
|
timeConstraint.RelativeDeadline = relativeDeadline;
|
|
timeConstraint.Deadline = new DateTime(0); //A 0-deadline means relative instead.
|
|
schedulerTask = Thread.CurrentThread.SchedulerThread.PrepareDelayedTask(taskToEnd, ref timeConstraint, SystemClock.GetKernelTime());
|
|
}
|
|
|
|
public override bool BeginConstraint(Hashtable resourceEstimates, DateTime deadline, ISchedulerTask taskToEnd, out ISchedulerTask schedulerTask)
|
|
{
|
|
DateTime timeNow = SystemClock.GetKernelTime();
|
|
LaxityThread thread = GetCurrentThread();
|
|
ulong start;
|
|
ulong stop;
|
|
Debug.Assert(!Processor.InterruptsDisabled());
|
|
|
|
thread.IpcCheckFreeConstraint();
|
|
|
|
start = Processor.CycleCount;
|
|
|
|
Debug.Assert(taskToEnd == null || taskToEnd == thread.ReservationStack);
|
|
bool end_previous = (taskToEnd != null);
|
|
TimeConstraint constraint = new TimeConstraint();
|
|
constraint.Deadline = deadline;
|
|
constraint.Estimate = CpuResource.Provider().CpuToTime((CpuResourceAmount)resourceEstimates[CpuResource.Provider().ResourceString]);
|
|
constraint.Start = timeNow;
|
|
|
|
bool ok = thread.BeginConstraintBeforeWaitValidate(end_previous, ref constraint, timeNow);
|
|
schedulerTask = thread.PendingReservation;
|
|
if (ok) {
|
|
OneShotReservation.BeginConstraintBeforeWait(thread, end_previous, constraint, timeNow);
|
|
bool iflag = Processor.DisableInterrupts();
|
|
ok = OneShotReservation.ResolveConstraint(thread);
|
|
Processor.RestoreInterrupts(iflag);
|
|
}
|
|
stop = Processor.CycleCount;
|
|
|
|
Scheduler.LogBeginConstraint(thread.EnclosingThread, ok, start, stop);
|
|
|
|
//TODO: Check if this is a necessity, or if it's only for sim time. Call in wrapper if necessary.
|
|
//NextThread();
|
|
return ok;
|
|
}
|
|
|
|
public override bool EndConstraint(ISchedulerTask taskToEnd)
|
|
{
|
|
Debug.Assert(!Processor.InterruptsDisabled());
|
|
Debug.Assert(taskToEnd == GetCurrentThread().ReservationStack);
|
|
bool iflag = Processor.DisableInterrupts();
|
|
bool ok = OneShotReservation.EndPreviousConstraint(GetCurrentThread(), SystemClock.GetKernelTime());
|
|
//
|
|
// need to reschedule only if on a reserved slot and the top of EarliestDeadlineFirst doesn't
|
|
// belong to this task
|
|
//
|
|
if ((OneShotReservation.CurrentReservation != null) &&
|
|
(OneShotReservation.TopGuaranteedReservation != null) &&
|
|
(OneShotReservation.TopGuaranteedReservation.ReservTask != (GetCurrentThread()))) {
|
|
Reschedule();
|
|
}
|
|
|
|
Processor.RestoreInterrupts(iflag);
|
|
Scheduler.LogEndConstraint();
|
|
|
|
//TODO: In the system wrapper for BeginConstraint -- it needs to call Yield/NextThread/MaybeYield
|
|
//NextThread();
|
|
return ok;
|
|
}
|
|
|
|
public static bool ReserveRecurringCpu(LaxityActivity activity,
|
|
ref TimeSpan amount,
|
|
ref TimeSpan period)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
#endregion
|
|
|
|
|
|
#region OneShotCpuReservation related functions
|
|
// OneShotCpuReservation related functions begin:
|
|
|
|
public static int ReleaseReservationProtected(OneShotReservation reservation)
|
|
{
|
|
int newrefcnt;
|
|
Debug.Assert(Processor.InterruptsDisabled());
|
|
|
|
Debug.Assert(reservation.ReferenceCount > 0);
|
|
newrefcnt = Interlocked.Decrement(ref reservation.ReferenceCount);
|
|
|
|
if (newrefcnt == 0) {
|
|
// Estimate may be positive when reservation reaches
|
|
// its Deadline w/o using its Estimate
|
|
Debug.Assert((reservation.Next == null) && (reservation.Previous == null));
|
|
if (reservation.OriginalThread != null) {
|
|
reservation.OriginalThread.ReleaseProtected();
|
|
//Debug.Assert(reservation.ActiveThread != null);
|
|
//reservation.ActiveThread.ReleaseProtected();
|
|
}
|
|
else {
|
|
Debug.Assert(reservation.AssociatedActivity != null);
|
|
ActivityReleaseProtected(reservation.AssociatedActivity);
|
|
}
|
|
Debug.Assert(reservation.Next == null);
|
|
CacheFreeReservation(reservation);
|
|
}
|
|
return newrefcnt;
|
|
}
|
|
|
|
|
|
public static OneShotReservation AllocateReservation()
|
|
{
|
|
OneShotReservation reservation;
|
|
|
|
// DisableInterrupts();
|
|
reservation = IpcAllocateReservation();
|
|
// EnableInterrupts();
|
|
|
|
if (reservation == null) {
|
|
reservation = new OneShotReservation(); //(PRESERVATION)malloc(sizeof(struct OneShotReservation)); // to be done while on the I-stack!
|
|
reservation.Clear();
|
|
}
|
|
return reservation;
|
|
}
|
|
|
|
static void FreeReservation(OneShotReservation reservation)
|
|
{
|
|
reservation = null; //free(reservation);
|
|
}
|
|
|
|
// Garbage-collect unused Reservations.
|
|
|
|
public static int ReleaseReservation(OneShotReservation reservation)
|
|
{
|
|
// Debug.Assert(!Processor.InterruptsDisabled());
|
|
Debug.Assert(reservation.ReferenceCount > 0);
|
|
int newrefcnt = reservation.ReferenceCount - 1;
|
|
reservation.ReferenceCount = newrefcnt;
|
|
|
|
if (newrefcnt == 0) {
|
|
// Estimate may be positive when reservation reaches its Deadline w/o using its Estimate
|
|
Debug.Assert((reservation.Next == null) && (reservation.Previous == null));
|
|
if (reservation.OriginalThread != null) {
|
|
reservation.OriginalThread.Release();
|
|
//Debug.Assert(reservation.ActiveThread != null);
|
|
//reservation.ActiveThread.Release();
|
|
}
|
|
else if (reservation.AssociatedActivity != null) {
|
|
ActivityObjRelease(reservation.AssociatedActivity);
|
|
}
|
|
CacheFreeReservation(reservation);
|
|
}
|
|
return newrefcnt;
|
|
}
|
|
|
|
// Like CheckFreeConstraint, but callable from the IPC path.
|
|
// Because we can't call AllocateReservation, we use the helper thread
|
|
// if there aren't any free Reservations.
|
|
static void CacheFreeReservation(OneShotReservation reservation)
|
|
{
|
|
if (reservation.OriginalThread != null &&
|
|
reservation.OriginalThread.FreeReservation == null) {
|
|
reservation.OriginalThread.FreeReservation = reservation;
|
|
}
|
|
else {
|
|
IpcFreeReservation(reservation);
|
|
}
|
|
}
|
|
|
|
|
|
// Callable with preemption disabled. Allocates a OneShotReservation
|
|
// from the global free list.
|
|
public static OneShotReservation IpcAllocateReservation()
|
|
{
|
|
OneShotReservation reservation;
|
|
|
|
if ((reservation = ReservationFreePool) != null) {
|
|
ReservationFreePool = reservation.FreeListNext;
|
|
}
|
|
|
|
return reservation;
|
|
}
|
|
|
|
|
|
// Callable with preemption disabled. Frees a OneShotReservation
|
|
// to the global free list.
|
|
public static void IpcFreeReservation(OneShotReservation reservation)
|
|
{
|
|
Debug.Assert( reservation != null);
|
|
Debug.Assert(reservation.ReferenceCount == 0);
|
|
|
|
reservation.FreeListNext = ReservationFreePool;
|
|
ReservationFreePool = reservation;
|
|
}
|
|
|
|
//////////////////////////////////////////////////////////////////////
|
|
|
|
public static void AddRefReservation(OneShotReservation reservation)
|
|
{
|
|
Debug.Assert(reservation.ReferenceCount >= 0);
|
|
reservation.ReferenceCount++;
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region Potpourri (Unregioned functions)
|
|
|
|
public static LaxityThread GetCurrentThread()
|
|
{
|
|
return ((LaxityProcessor)Processor.CurrentProcessor.SchedulerProcessor).RunningThread;
|
|
}
|
|
|
|
public static void IChangeCurrentThread(LaxityThread thread)
|
|
{
|
|
((LaxityProcessor)Processor.CurrentProcessor.SchedulerProcessor).RunningThread = thread;
|
|
}
|
|
|
|
// Auxiliary Routines.
|
|
// TODO: Revisit the necessity of these functions.
|
|
public static TimeSpan minInterval(TimeSpan TimeInterv0, TimeSpan TimeInterv1)
|
|
{
|
|
return (TimeInterv0 < TimeInterv1? TimeInterv0: TimeInterv1);
|
|
}
|
|
|
|
public static DateTime minTime(DateTime Time0, DateTime Time1)
|
|
{
|
|
return (Time0 < Time1? Time0: Time1);
|
|
}
|
|
|
|
static TimeSpan maxInterval(TimeSpan TimeInterv0, TimeSpan TimeInterv1)
|
|
{
|
|
return (TimeInterv0 < TimeInterv1? TimeInterv1: TimeInterv0);
|
|
}
|
|
|
|
static DateTime maxTime(DateTime Time0, DateTime Time1)
|
|
{
|
|
return (Time0 < Time1? Time1: Time0);
|
|
}
|
|
|
|
internal static LaxityProcessor GetCurrentProcessor()
|
|
{
|
|
return (LaxityProcessor)Processor.CurrentProcessor.SchedulerProcessor;
|
|
}
|
|
|
|
// Add Activity in the last Round-Robin position.
|
|
public static void EnqueueActivity(LaxityActivity activity)
|
|
{
|
|
Debug.Assert(Processor.InterruptsDisabled());
|
|
if (CircularActivityList == null) {
|
|
NextActivity = CircularActivityList /*= GetCurrentProcessor().CurrentActivity */=
|
|
activity.Next = activity.Previous = activity;
|
|
//Here modifying other processor specific data rather than global.
|
|
// for (int i=0; i<Processor.processorTable.Length; i++) {
|
|
// ((LaxityProcessor)Processor.processorTable[i].SchedulerProcessor).NextActivity = activity;
|
|
// ((LaxityProcessor)Processor.processorTable[i].SchedulerProcessor).Reschedule();
|
|
// }
|
|
SchedulerClock.SignalOtherProcessors();
|
|
}
|
|
else {
|
|
activity.Next = NextActivity;
|
|
activity.Previous = NextActivity.Previous;
|
|
NextActivity.Previous.Next = activity;
|
|
NextActivity.Previous = activity;
|
|
}
|
|
}
|
|
|
|
public static void DequeueActivity(LaxityActivity activity) //TODO: Make an activity function?
|
|
{
|
|
// In our simulated environment, Activity 0 is never removed from the Q.
|
|
Debug.Assert(Processor.InterruptsDisabled());
|
|
//NOTE: Might be replaced with a test and return.
|
|
Debug.Assert(activity.Next != null);
|
|
Debug.Assert(activity.Previous != null);
|
|
|
|
// Previous. in Laxity if (activity.Id == 0) return;
|
|
|
|
activity.Next.Previous = activity.Previous;
|
|
activity.Previous.Next = activity.Next;
|
|
if (CircularActivityList == activity) {
|
|
CircularActivityList = activity.Next;
|
|
}
|
|
if (NextActivity == activity) {
|
|
NextActivity = activity.Next;
|
|
}
|
|
// for (int i=0; i<Processor.processorTable.Length; i++) {
|
|
// LaxityProcessor processor = (LaxityProcessor)Processor.processorTable[i].SchedulerProcessor;
|
|
// if (processor.NextActivity == activity) {
|
|
// processor.NextActivity = activity.Next;
|
|
// }
|
|
// }
|
|
}
|
|
|
|
// if possible, places thread in the 2nd position in the RunnableThreads Q.
|
|
// Make this a function on a resource container.
|
|
public static void EnqueueRunThread(LaxityThread thread, bool fromSleeping)
|
|
{
|
|
Debug.Assert(Processor.InterruptsDisabled());
|
|
LaxityActivity activity = thread.AssociatedActivity;
|
|
if (thread.Next != null) {
|
|
Debug.Assert(thread.Previous != null);
|
|
return;
|
|
}
|
|
|
|
// Debug.Assert(thread.QueueType == QUEUE_NONE);
|
|
|
|
//if (thread.State == LaxityThread.ThreadState.ThreadWaiting)
|
|
// thread.SetState(LaxityThread.ThreadState.ThreadReady);
|
|
|
|
if (activity.RunnableThreads == null) {
|
|
thread.Next = thread.Previous = thread;
|
|
activity.RunnableThreads = thread;
|
|
}
|
|
else {
|
|
if (fromSleeping) {
|
|
thread.Previous = activity.RunnableThreads;
|
|
thread.Next = activity.RunnableThreads.Next;
|
|
activity.RunnableThreads.Next.Previous = thread;
|
|
activity.RunnableThreads.Next = thread;
|
|
}
|
|
else {
|
|
//If we weren't sleeping/waiting, then we were running --
|
|
// then put thread at end of list, not 2nd.
|
|
thread.Next = activity.RunnableThreads;
|
|
thread.Previous = activity.RunnableThreads.Previous;
|
|
activity.RunnableThreads.Previous.Next = thread;
|
|
activity.RunnableThreads.Previous = thread;
|
|
}
|
|
}
|
|
//Editing other processor data again. Here we actually tell all
|
|
//processors they need to reschedule, since there is a new thread to
|
|
//consider. (perhaps wrong).
|
|
//NOTE: SignalOtherProcessors only alerts those who are halted at the
|
|
//moment.
|
|
for (int i=0; i<Processor.processorTable.Length; i++) {
|
|
((LaxityProcessor)Processor.processorTable[i].SchedulerProcessor).Reschedule();
|
|
}
|
|
SchedulerClock.SignalOtherProcessors();
|
|
}
|
|
|
|
public static bool DequeueRunThread(LaxityThread thread)
|
|
{
|
|
Debug.Assert(Processor.InterruptsDisabled());
|
|
if (thread.Next == null) {
|
|
Debug.Assert(thread.Previous == null);
|
|
return false;
|
|
}
|
|
|
|
if (thread.Next == thread) {
|
|
Debug.Assert(thread.Previous == thread);
|
|
thread.AssociatedActivity.RunnableThreads = null;
|
|
}
|
|
else {
|
|
// multiple threads in the RunnableThreads Q
|
|
thread.Previous.Next = thread.Next;
|
|
thread.Next.Previous = thread.Previous;
|
|
if (thread.AssociatedActivity.RunnableThreads == thread) {
|
|
thread.AssociatedActivity.RunnableThreads = thread.Next;
|
|
}
|
|
}
|
|
thread.Next = thread.Previous = null;
|
|
return true;
|
|
}
|
|
#endregion
|
|
|
|
#region Additions according to kernel implementation
|
|
|
|
static bool ResetTimerTimeout(DateTime NewTimerTimeout)
|
|
{
|
|
|
|
DateTime timeNow = SchedulingTime;
|
|
|
|
if (timeNow > NewTimerTimeout) {
|
|
return false;
|
|
}
|
|
|
|
Debug.Assert(Processor.InterruptsDisabled());
|
|
// Debug.Assert(CurrentThread()->GetState() == Thread.ThreadState.ThreadRunning);
|
|
|
|
Debug.Assert(NewTimerTimeout > SchedulingTime);
|
|
// Debug.Assert(SleepTimeout > SchedulingTime);
|
|
|
|
//TODO: Need LA_Time?
|
|
// if (NewTimerTimeout > SleepTimeout - LA_Time)
|
|
// NewTimerTimeout = SleepTimeout - LA_Time;
|
|
if (NewTimerTimeout > LaxityThread.GetSleepTimeout()) {
|
|
NewTimerTimeout = LaxityThread.GetSleepTimeout();
|
|
}
|
|
|
|
//DebugStub.Print("Setting Next Interrupt for: {0} ....\n",
|
|
//__arglist(NewTimerTimeout.Ticks));
|
|
bool success = SchedulerClock.SetNextInterrupt(NewTimerTimeout); //TODO: Perhaps only call this if the time changed.
|
|
|
|
//DebugStub.Print(success?"SUCCESS\n":"FAILED\n");
|
|
|
|
return success;
|
|
}
|
|
|
|
public static void UpdateSchedulingStatus()
|
|
{
|
|
TimeSpan timeRun;
|
|
LaxityThread currentThread = GetCurrentThread();
|
|
|
|
DateTime newSchedulingTime = SystemClock.GetKernelTime();
|
|
|
|
timeRun = newSchedulingTime - SchedulingTime;
|
|
LaxityProcessor processor = (LaxityProcessor)Processor.CurrentProcessor.SchedulerProcessor;
|
|
processor.SchedulingTime = newSchedulingTime;
|
|
|
|
if (Idle) {
|
|
// UpdateIdleTime
|
|
IdleTime += timeRun;
|
|
return;
|
|
}
|
|
|
|
// If IDLE compute CurrentPlanNode & set currentThread to null.
|
|
if (currentThread != null) {
|
|
// Unless thread just exited,
|
|
// Update Thread & Activity execution times.
|
|
currentThread.AddExecutionTime(timeRun);
|
|
Scheduler.CurrentTask().AddResourceAmountUsed(CpuResource.Provider().ResourceString, CpuResource.Provider().TimeToCpu(timeRun));
|
|
// if (currentThread.AssociatedActivity != null) {
|
|
// currentThread.AssociatedActivity.MyRecurringCpuReservation.EnclosingCpuReservation.AddTimeUsed(timeRun);
|
|
// }
|
|
}
|
|
if (OneShotReservation.CurrentReservation != null) {
|
|
// Slice used for a reservation.
|
|
OneShotReservation.CurrentReservation.Estimate -= timeRun;
|
|
}
|
|
else if (processor.CurrentActivity != null) {
|
|
// Slice used for round robin.
|
|
processor.SliceLeft -= timeRun;
|
|
processor.CurrentActivity = null;
|
|
}
|
|
}
|
|
|
|
internal static void CheckInvariants()
|
|
{
|
|
if (CircularActivityList != null) {
|
|
bool listNextFound = (CircularActivityList == NextActivity);
|
|
LaxityActivity start = CircularActivityList, current = CircularActivityList.Next, previous = CircularActivityList;
|
|
while (current != start) {
|
|
//perhaps check thread invariants here too.
|
|
Debug.Assert(current != null, "resource container list is not circular");
|
|
Debug.Assert(current.Previous == previous, "back pointer doesn't match forward pointer");
|
|
if (current == NextActivity) {
|
|
listNextFound = true;
|
|
}
|
|
previous = current;
|
|
current = current.Next;
|
|
}
|
|
Debug.Assert(listNextFound, "NextActivity isn't in the loop!");
|
|
Debug.Assert(current.Previous == previous, "Head doesn't point to tail");
|
|
}
|
|
}
|
|
|
|
// Always called when another thread needs to be scheduled.
|
|
static bool RescheduleInterrupt()
|
|
{
|
|
CheckInvariants();
|
|
Debug.Assert(Processor.InterruptsDisabled());
|
|
Debug.Assert(!Processor.InterruptsDisabled());
|
|
LaxityThread currentThread = GetCurrentThread();
|
|
Debug.Assert(currentThread == null || currentThread.ActiveProcessor == GetCurrentProcessor());
|
|
if (currentThread != null) {
|
|
currentThread.ActiveProcessor = null;
|
|
}
|
|
|
|
DateTime nextStart;
|
|
LaxityThread previousThread;
|
|
|
|
RescheduleAgain: // !!!!!!!!!! SIM ONLY !!!!!!!!!
|
|
if (Idle) {
|
|
currentThread = null;
|
|
}
|
|
|
|
previousThread = currentThread;
|
|
|
|
UpdateSchedulingStatus();
|
|
|
|
// if thread was the head of the runnable threads Q:
|
|
// Advance the runnable threads Q.
|
|
if ((currentThread != null) &&
|
|
(currentThread.AssociatedActivity != null) &&
|
|
(currentThread.AssociatedActivity.RunnableThreads == currentThread)) {
|
|
currentThread.AssociatedActivity.RunnableThreads = currentThread.Next;
|
|
Debug.Assert(currentThread.AssociatedActivity.RunnableThreads != null);
|
|
}
|
|
|
|
OneShotReservation.UpdateCurrentReservation();
|
|
OneShotReservation.ClearCurrentReservation();
|
|
currentThread = null;
|
|
|
|
// Finished first stage, i.e. updated state.
|
|
// Start second stage: wakeup threads & select Next CPU slice.
|
|
|
|
LaxityThread.WakeThreads();
|
|
|
|
// NOTE: In the original Laxity Simulator Code (& MMOSA code)
|
|
// The call to DrainDeferredConditions() was made here.
|
|
// In Singularity, this will basically be replaced with a
|
|
// queue of wait-events to fix.
|
|
|
|
OneShotReservation.FreshenReservationQueues();
|
|
|
|
TimeSpan currentNodeSliceLeft;
|
|
LaxityProcessor currentProcessor = (LaxityProcessor)Processor.CurrentProcessor.SchedulerProcessor;
|
|
if (currentProcessor.CurrentActivity != null && currentProcessor.SliceLeft >= LaxityScheduler.MinSlice) {
|
|
currentThread = currentProcessor.CurrentActivity.GetRunnableThread();
|
|
if (currentThread != null) {
|
|
goto exit;
|
|
}
|
|
}
|
|
|
|
// Find runnable one-shot reservation if any.
|
|
OneShotReservation.FindRunnableReservation(ref currentThread);
|
|
if (currentThread != null) {
|
|
goto exit;
|
|
}
|
|
|
|
// Find next runnable Activity.
|
|
currentProcessor.SliceLeft = LaxityScheduler.RobinSlice;
|
|
currentProcessor.CurrentActivity = NextActivity; // !!!!!!!!!!!!!SIM ONLY !!!!!!!!!!
|
|
while ((currentThread = NextActivity.GetRunnableThread()) == null) {
|
|
NextActivity = NextActivity.Next;
|
|
//currentProcessor.SliceLeft = LaxityScheduler.LaxitySlice;
|
|
if (NextActivity == currentProcessor.CurrentActivity) {
|
|
// !!!!!!!!SIM ONLY !!!!!!!
|
|
// in the real scheduler, execute halt
|
|
if (OneShotReservation.IdleReservations != null) {
|
|
// reuse nextStart
|
|
nextStart = minTime(LaxityThread.GetSleepTimeout(), OneShotReservation.IdleReservations.Start);
|
|
}
|
|
else {
|
|
nextStart = LaxityThread.GetSleepTimeout();
|
|
DebugStub.Print("Idle, sleeping until {0} cf maxvalue {1}\n",
|
|
__arglist(nextStart.Ticks,
|
|
DateTime.MaxValue.Ticks));
|
|
}
|
|
if (nextStart == DateTime.MaxValue) {
|
|
Scheduler.StopSystem();
|
|
}
|
|
if (! ResetTimerTimeout(nextStart)) {
|
|
//Error setting timer. Try scheduling again.
|
|
DebugStub.Print("Thought Idle, failed to set interrupt.\n");
|
|
goto RescheduleAgain;
|
|
}
|
|
GetCurrentProcessor().Idle = true;
|
|
|
|
// !!!!!!!!SIM ONLY !!!!!!!
|
|
currentThread = null; // !!!!!!!!SIM ONLY !!!!!!!
|
|
OneShotReservation.ClearCurrentReservation();
|
|
currentProcessor.CurrentActivity = null;
|
|
|
|
if (DateTime.MaxValue != nextStart) {
|
|
//Scheduler.LogTimeJump();
|
|
}
|
|
|
|
//DebugStub.Print("Halted.\n");
|
|
IChangeCurrentThread(null);
|
|
return true; // !!!!!!!!SIM ONLY !!!!!!!
|
|
}
|
|
// !!!!!!!!SIM ONLY !!!!!!!
|
|
}
|
|
//DebugStub.Print("Running Round Robin Resource Container\n");
|
|
currentProcessor.CurrentActivity = NextActivity; // we probably need only one of the two variables
|
|
NextActivity = NextActivity.Next;
|
|
|
|
exit:
|
|
currentNodeSliceLeft = currentProcessor.SliceLeft;
|
|
|
|
Debug.Assert(currentThread != null);
|
|
if (currentThread != previousThread) {
|
|
Scheduler.LogContextSwitch(); // Context Switch statistics
|
|
}
|
|
|
|
if (OneShotReservation.IdleReservations != null) {
|
|
// reuse nextStart
|
|
nextStart = minTime(LaxityThread.GetSleepTimeout(), OneShotReservation.IdleReservations.Start);
|
|
}
|
|
else {
|
|
nextStart = LaxityThread.GetSleepTimeout();
|
|
}
|
|
|
|
if (SchedulingTime + currentNodeSliceLeft /* CurrentSlice */ > nextStart) {
|
|
currentNodeSliceLeft /* CurrentSlice */ = nextStart - currentProcessor.SchedulingTime;
|
|
}
|
|
|
|
Scheduler.LogReschedule();
|
|
if (!ResetTimerTimeout(currentProcessor.SchedulingTime + currentNodeSliceLeft) || Scheduler.TimerInterruptedFlag) {
|
|
//TODO: What do we REALLY want here?
|
|
currentThread = null; // !!!!!!!!SIM ONLY !!!!!!!
|
|
OneShotReservation.ClearCurrentReservation();
|
|
currentProcessor.CurrentActivity = null;
|
|
goto RescheduleAgain;
|
|
}
|
|
|
|
Debug.Assert(currentThread.ActiveProcessor == null);
|
|
currentThread.ActiveProcessor = GetCurrentProcessor();
|
|
Debug.Assert(currentThread.ActiveProcessor != null);
|
|
|
|
if (currentThread != previousThread) {
|
|
IChangeCurrentThread(currentThread);
|
|
}
|
|
GetCurrentProcessor().Idle = false;
|
|
|
|
// Not necessarily true: Debug.Assert(!Scheduler.TimerInterruptedFlag);
|
|
CheckInvariants();
|
|
return false;
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region Laxity Changes
|
|
|
|
|
|
#endregion
|
|
|
|
#region Constraint feasibility analysis support functions
|
|
// Node can provide more than time than necessary between start and deadline; come shorter deadline:
|
|
// add a new pointer to a reservation to a node and clean the ordered array
|
|
#endregion
|
|
|
|
public static void Reschedule()
|
|
{
|
|
((LaxityProcessor)Processor.CurrentProcessor.SchedulerProcessor).Reschedule();
|
|
}
|
|
|
|
public static void ActivityObjAddRef(LaxityActivity activity)
|
|
{
|
|
activity.ReferenceCount++;
|
|
}
|
|
|
|
|
|
public static void ActivityObjRelease(LaxityActivity activity)
|
|
{
|
|
Debug.Assert(activity.ReferenceCount >= 1);
|
|
activity.ReleaseReference();
|
|
}
|
|
|
|
public static void ActivityReleaseProtected(LaxityActivity activity)
|
|
{
|
|
Debug.Assert(activity.ReferenceCount >= 1);
|
|
Debug.Assert(Processor.InterruptsDisabled(), "Interrupts Not Disabled!");
|
|
activity.ReleaseReference();
|
|
}
|
|
}
|
|
}
|