thrdini.c File Reference

#include <ntoskrnl.h>
#include <debug.h>

Include dependency graph for thrdini.c:

Go to the source code of this file.

Classes
struct	_KSWITCHFRAME
struct	_KSTART_FRAME
struct	_KUINIT_FRAME
struct	_KKINIT_FRAME

Macros
#define	NDEBUG

Typedefs
typedef struct _KSWITCHFRAME	KSWITCHFRAME
typedef struct _KSWITCHFRAME *	PKSWITCHFRAME
typedef struct _KSTART_FRAME	KSTART_FRAME
typedef struct _KSTART_FRAME *	PKSTART_FRAME
typedef struct _KUINIT_FRAME	KUINIT_FRAME
typedef struct _KUINIT_FRAME *	PKUINIT_FRAME
typedef struct _KKINIT_FRAME	KKINIT_FRAME
typedef struct _KKINIT_FRAME *	PKKINIT_FRAME

Functions
VOID FASTCALL	KiSwitchThreads (IN PKTHREAD OldThread, IN PKTHREAD NewThread)
VOID FASTCALL	KiRetireDpcListInDpcStack (IN PKPRCB Prcb, IN PVOID DpcStack)
VOID NTAPI	KiThreadStartup (VOID)
VOID NTAPI	KiInitializeContextThread (IN PKTHREAD Thread, IN PKSYSTEM_ROUTINE SystemRoutine, IN PKSTART_ROUTINE StartRoutine, IN PVOID StartContext, IN PCONTEXT ContextPointer)
DECLSPEC_NORETURN VOID	KiIdleLoop (VOID)
BOOLEAN FASTCALL	KiSwapContextExit (IN PKTHREAD OldThread, IN PKSWITCHFRAME SwitchFrame)
VOID FASTCALL	KiSwapContextEntry (IN PKSWITCHFRAME SwitchFrame, IN ULONG_PTR OldThreadAndApcFlag)
VOID NTAPI	KiDispatchInterrupt (VOID)

Macro Definition Documentation

NDEBUG

#define NDEBUG

Definition at line 12 of file thrdini.c.

Typedef Documentation

KKINIT_FRAME

typedef struct _KKINIT_FRAME KKINIT_FRAME

KSTART_FRAME

typedef struct _KSTART_FRAME KSTART_FRAME

KSWITCHFRAME

typedef struct _KSWITCHFRAME KSWITCHFRAME

KUINIT_FRAME

typedef struct _KUINIT_FRAME KUINIT_FRAME

PKKINIT_FRAME

typedef struct _KKINIT_FRAME * PKKINIT_FRAME

PKSTART_FRAME

typedef struct _KSTART_FRAME * PKSTART_FRAME

PKSWITCHFRAME

typedef struct _KSWITCHFRAME * PKSWITCHFRAME

PKUINIT_FRAME

typedef struct _KUINIT_FRAME * PKUINIT_FRAME

Function Documentation

KiDispatchInterrupt()

VOID NTAPI KiDispatchInterrupt

(

VOID

)

Definition at line 469 of file thrdini.c.

{
    PKIPCR Pcr = (PKIPCR)KeGetPcr();
    PKPRCB Prcb = &Pcr->PrcbData;
    PVOID OldHandler;
    PKTHREAD NewThread, OldThread;
 
    /* Disable interrupts */
    _disable();
 
    /* Check for pending timers, pending DPCs, or pending ready threads */
    if ((Prcb->DpcData[0].DpcQueueDepth) ||
        (Prcb->TimerRequest) ||
        (Prcb->DeferredReadyListHead.Next))
    {
        /* Switch to safe execution context */
        OldHandler = Pcr->NtTib.ExceptionList;
        Pcr->NtTib.ExceptionList = EXCEPTION_CHAIN_END;
 
        /* Retire DPCs while under the DPC stack */
        KiRetireDpcListInDpcStack(Prcb, Prcb->DpcStack);
 
        /* Restore context */
        Pcr->NtTib.ExceptionList = OldHandler;
    }
 
    /* Re-enable interrupts */
    _enable();
 
    /* Check for quantum end */
    if (Prcb->QuantumEnd)
    {
        /* Handle quantum end */
        Prcb->QuantumEnd = FALSE;
        KiQuantumEnd();
    }
    else if (Prcb->NextThread)
    {
        /* Acquire the PRCB lock */
        KiAcquirePrcbLock(Prcb);
 
        /* Capture current thread data */
        OldThread = Prcb->CurrentThread;
        NewThread = Prcb->NextThread;
 
        /* Set new thread data */
        Prcb->NextThread = NULL;
        Prcb->CurrentThread = NewThread;
 
        /* The thread is now running */
        NewThread->State = Running;
        OldThread->WaitReason = WrDispatchInt;
 
        /* Make the old thread ready */
        KxQueueReadyThread(OldThread, Prcb);
 
        /* Swap to the new thread */
        KiSwapContext(APC_LEVEL, OldThread);
    }
}

KiIdleLoop()

DECLSPEC_NORETURN VOID KiIdleLoop

(

VOID

)

Definition at line 260 of file thrdini.c.

{
    PKPRCB Prcb = KeGetCurrentPrcb();
    PKTHREAD OldThread, NewThread;
 
    /* Now loop forever */
    while (TRUE)
    {
        /* Start of the idle loop: disable interrupts */
        _enable();
        YieldProcessor();
        YieldProcessor();
        _disable();
 
        /* Check for pending timers, pending DPCs, or pending ready threads */
        if ((Prcb->DpcData[0].DpcQueueDepth) ||
            (Prcb->TimerRequest) ||
            (Prcb->DeferredReadyListHead.Next))
        {
            /* Quiesce the DPC software interrupt */
            HalClearSoftwareInterrupt(DISPATCH_LEVEL);
 
            /* Handle it */
            KiRetireDpcList(Prcb);
        }
 
        /* Check if a new thread is scheduled for execution */
        if (Prcb->NextThread)
        {
            /* Enable interrupts */
            _enable();
 
            /* Capture current thread data */
            OldThread = Prcb->CurrentThread;
            NewThread = Prcb->NextThread;
 
            /* Set new thread data */
            Prcb->NextThread = NULL;
            Prcb->CurrentThread = NewThread;
 
            /* The thread is now running */
            NewThread->State = Running;
 
#ifdef CONFIG_SMP
            /* Do the swap at SYNCH_LEVEL */
            KfRaiseIrql(SYNCH_LEVEL);
#endif
 
            /* Switch away from the idle thread */
            KiSwapContext(APC_LEVEL, OldThread);
 
#ifdef CONFIG_SMP
            /* Go back to DISPATCH_LEVEL */
            KeLowerIrql(DISPATCH_LEVEL);
#endif
        }
        else
        {
            /* Continue staying idle. Note the HAL returns with interrupts on */
            Prcb->PowerState.IdleFunction(&Prcb->PowerState);
        }
    }
}

Referenced by KiInitializeSystem(), and KiSystemStartupBootStack().

KiInitializeContextThread()

VOID NTAPI KiInitializeContextThread	(	IN PKTHREAD	Thread,
		IN PKSYSTEM_ROUTINE	SystemRoutine,
		IN PKSTART_ROUTINE	StartRoutine,
		IN PVOID	StartContext,
		IN PCONTEXT	ContextPointer
	)

Definition at line 92 of file thrdini.c.

{
    PFX_SAVE_AREA FxSaveArea;
    PFXSAVE_FORMAT FxSaveFormat;
    PKSTART_FRAME StartFrame;
    PKSWITCHFRAME CtxSwitchFrame;
    PKTRAP_FRAME TrapFrame;
    CONTEXT LocalContext;
    PCONTEXT Context = NULL;
    ULONG ContextFlags;
 
    /* Check if this is a With-Context Thread */
    if (ContextPointer)
    {
        /* Set up the Initial Frame */
        PKUINIT_FRAME InitFrame;
        InitFrame = (PKUINIT_FRAME)((ULONG_PTR)Thread->InitialStack -
                                    sizeof(KUINIT_FRAME));
 
        /* Copy over the context we got */
        RtlCopyMemory(&LocalContext, ContextPointer, sizeof(CONTEXT));
        Context = &LocalContext;
        ContextFlags = CONTEXT_CONTROL;
 
        /* Zero out the trap frame and save area */
        RtlZeroMemory(&InitFrame->TrapFrame,
                      KTRAP_FRAME_LENGTH + sizeof(FX_SAVE_AREA));
 
        /* Setup the Fx Area */
        FxSaveArea = &InitFrame->FxSaveArea;
 
        /* Check if we support FXsr */
        if (KeI386FxsrPresent)
        {
            /* Get the FX Save Format Area */
            FxSaveFormat = (PFXSAVE_FORMAT)Context->ExtendedRegisters;
 
            /* Set an initial state */
            FxSaveFormat->ControlWord = 0x27F;
            FxSaveFormat->StatusWord = 0;
            FxSaveFormat->TagWord = 0;
            FxSaveFormat->ErrorOffset = 0;
            FxSaveFormat->ErrorSelector = 0;
            FxSaveFormat->DataOffset = 0;
            FxSaveFormat->DataSelector = 0;
            FxSaveFormat->MXCsr = 0x1F80;
        }
        else
        {
            /* Setup the regular save area */
            Context->FloatSave.ControlWord = 0x27F;
            Context->FloatSave.StatusWord = 0;
            Context->FloatSave.TagWord = -1;
            Context->FloatSave.ErrorOffset = 0;
            Context->FloatSave.ErrorSelector = 0;
            Context->FloatSave.DataOffset =0;
            Context->FloatSave.DataSelector = 0;
        }
 
        /* Set an intial NPX State */
        Context->FloatSave.Cr0NpxState = 0;
        FxSaveArea->Cr0NpxState = 0;
        FxSaveArea->NpxSavedCpu = 0;
 
        /* Now set the context flags depending on XMM support */
        ContextFlags |= (KeI386FxsrPresent) ? CONTEXT_EXTENDED_REGISTERS : CONTEXT_FLOATING_POINT;
 
        /* Set the Thread's NPX State */
        Thread->NpxState = NPX_STATE_NOT_LOADED;
        Thread->Header.NpxIrql = PASSIVE_LEVEL;
 
        /* Disable any debug registers */
        Context->ContextFlags &= ~CONTEXT_DEBUG_REGISTERS;
 
        /* Setup the Trap Frame */
        TrapFrame = &InitFrame->TrapFrame;
 
        /* Set up a trap frame from the context. */
        KeContextToTrapFrame(Context,
                             NULL,
                             TrapFrame,
                             Context->ContextFlags | ContextFlags,
                             UserMode);
 
        /* Set SS, DS, ES's RPL Mask properly */
        TrapFrame->HardwareSegSs |= RPL_MASK;
        TrapFrame->SegDs |= RPL_MASK;
        TrapFrame->SegEs |= RPL_MASK;
        TrapFrame->Dr7 = 0;
 
        /* Set the debug mark */
        TrapFrame->DbgArgMark = 0xBADB0D00;
 
        /* Set the previous mode as user */
        TrapFrame->PreviousPreviousMode = UserMode;
 
        /* Terminate the Exception Handler List */
        TrapFrame->ExceptionList = EXCEPTION_CHAIN_END;
 
        /* Setup the Stack for KiThreadStartup and Context Switching */
        StartFrame = &InitFrame->StartFrame;
        CtxSwitchFrame = &InitFrame->CtxSwitchFrame;
 
        /* Tell the thread it will run in User Mode */
        Thread->PreviousMode = UserMode;
 
        /* Tell KiThreadStartup of that too */
        StartFrame->UserThread = TRUE;
    }
    else
    {
        /* Set up the Initial Frame for the system thread */
        PKKINIT_FRAME InitFrame;
        InitFrame = (PKKINIT_FRAME)((ULONG_PTR)Thread->InitialStack -
                                    sizeof(KKINIT_FRAME));
 
        /* Setup the Fx Area */
        FxSaveArea = &InitFrame->FxSaveArea;
        RtlZeroMemory(FxSaveArea, sizeof(FX_SAVE_AREA));
 
        /* Check if we have Fxsr support */
        if (KeI386FxsrPresent)
        {
            /* Set the stub FX area */
            FxSaveArea->U.FxArea.ControlWord = 0x27F;
            FxSaveArea->U.FxArea.MXCsr = 0x1F80;
        }
        else
        {
            /* Set the stub FN area */
            FxSaveArea->U.FnArea.ControlWord = 0x27F;
            FxSaveArea->U.FnArea.TagWord = -1;
        }
 
        /* No NPX State */
        Thread->NpxState = NPX_STATE_NOT_LOADED;
 
        /* Setup the Stack for KiThreadStartup and Context Switching */
        StartFrame = &InitFrame->StartFrame;
        CtxSwitchFrame = &InitFrame->CtxSwitchFrame;
 
        /* Tell the thread it will run in Kernel Mode */
        Thread->PreviousMode = KernelMode;
 
        /* Tell KiThreadStartup of that too */
        StartFrame->UserThread = FALSE;
    }
 
    /* Now setup the remaining data for KiThreadStartup */
    StartFrame->StartContext = StartContext;
    StartFrame->StartRoutine = StartRoutine;
    StartFrame->SystemRoutine = SystemRoutine;
 
    /* And set up the Context Switch Frame */
    CtxSwitchFrame->RetAddr = KiThreadStartup;
    CtxSwitchFrame->ApcBypassDisable = TRUE;
    CtxSwitchFrame->ExceptionList = EXCEPTION_CHAIN_END;
 
    /* Save back the new value of the kernel stack. */
    Thread->KernelStack = (PVOID)CtxSwitchFrame;
}

KiRetireDpcListInDpcStack()

VOID FASTCALL KiRetireDpcListInDpcStack	(	IN PKPRCB	Prcb,
		IN PVOID	DpcStack
	)

Referenced by KiDispatchInterrupt().

KiSwapContextEntry()

VOID FASTCALL KiSwapContextEntry	(	IN PKSWITCHFRAME	SwitchFrame,
		IN ULONG_PTR	OldThreadAndApcFlag
	)

Definition at line 422 of file thrdini.c.

{
    PKIPCR Pcr = (PKIPCR)KeGetPcr();
    PKTHREAD OldThread, NewThread;
    ULONG Cr0, NewCr0;
 
    /* Save APC bypass disable */
    SwitchFrame->ApcBypassDisable = OldThreadAndApcFlag & 3;
    SwitchFrame->ExceptionList = Pcr->NtTib.ExceptionList;
 
    /* Increase context switch count and check if tracing is enabled */
    Pcr->ContextSwitches++;
    if (Pcr->PerfGlobalGroupMask)
    {
        /* We don't support this yet on x86 either */
        DPRINT1("WMI Tracing not supported\n");
        ASSERT(FALSE);
    }
 
    /* Get thread pointers */
    OldThread = (PKTHREAD)(OldThreadAndApcFlag & ~3);
    NewThread = Pcr->PrcbData.CurrentThread;
 
    /* Get the old thread and set its kernel stack */
    OldThread->KernelStack = SwitchFrame;
 
    /* Set swapbusy to false for the new thread */
    NewThread->SwapBusy = FALSE;
 
    /* ISRs can change FPU state, so disable interrupts while checking */
    _disable();
 
    /* Get current and new CR0 and check if they've changed */
    Cr0 = __readcr0();
    NewCr0 = NewThread->NpxState |
             (Cr0 & ~(CR0_MP | CR0_EM | CR0_TS)) |
             KiGetThreadNpxArea(NewThread)->Cr0NpxState;
    if (Cr0 != NewCr0)  __writecr0(NewCr0);
 
    /* Now enable interrupts and do the switch */
    _enable();
    KiSwitchThreads(OldThread, NewThread->KernelStack);
}

KiSwapContextExit()

BOOLEAN FASTCALL KiSwapContextExit	(	IN PKTHREAD	OldThread,
		IN PKSWITCHFRAME	SwitchFrame
	)

Definition at line 326 of file thrdini.c.

{
    PKIPCR Pcr = (PKIPCR)KeGetPcr();
    PKPROCESS OldProcess, NewProcess;
    PKTHREAD NewThread;
    ULONG64 CurrentCycleTime, ElapsedCycles, NewCycleTime;
 
    /* We are on the new thread stack now */
    NewThread = Pcr->PrcbData.CurrentThread;
 
    /* Now we are the new thread. Check if it's in a new process */
    OldProcess = OldThread->ApcState.Process;
    NewProcess = NewThread->ApcState.Process;
    if (OldProcess != NewProcess)
    {
        /* Check if there is a different LDT */
        if (*(PULONGLONG)&OldProcess->LdtDescriptor != *(PULONGLONG)&NewProcess->LdtDescriptor)
        {
            if (NewProcess->LdtDescriptor.LimitLow)
            {
                KeSetGdtSelector(KGDT_LDT,
                                 ((PULONG)&NewProcess->LdtDescriptor)[0],
                                 ((PULONG)&NewProcess->LdtDescriptor)[1]);
                Ke386SetLocalDescriptorTable(KGDT_LDT);
            }
            else
            {
                Ke386SetLocalDescriptorTable(0);
            }
        }
 
        /* Switch address space and flush TLB */
        __writecr3(NewProcess->DirectoryTableBase[0]);
    }
 
    /* Update the old thread's cycle time */
    CurrentCycleTime = __rdtsc();
    ElapsedCycles = CurrentCycleTime - Pcr->PrcbData.StartCycles;
    NewCycleTime = ((PETHREAD)OldThread)->CycleTime + ElapsedCycles;
    KiWriteThreadCycleTime(OldThread, NewCycleTime);
    InterlockedAdd64((PLONG64)&((PEPROCESS)OldProcess)->CycleTime, ElapsedCycles);
    Pcr->PrcbData.StartCycles = CurrentCycleTime;
 
    /* Clear GS */
    Ke386SetGs(0);
 
    /* Set the TEB */
    KiSetTebBase((PKPCR)Pcr, &NewThread->Teb->NtTib);
 
    /* Set new TSS fields */
    Pcr->TSS->Esp0 = (ULONG_PTR)NewThread->InitialStack;
    if (!((KeGetTrapFrame(NewThread))->EFlags & EFLAGS_V86_MASK))
    {
        Pcr->TSS->Esp0 -= sizeof(KTRAP_FRAME) - FIELD_OFFSET(KTRAP_FRAME, V86Es);
    }
    Pcr->TSS->Esp0 -= NPX_FRAME_LENGTH;
    Pcr->TSS->IoMapBase = NewProcess->IopmOffset;
 
    /* Increase thread context switches */
    NewThread->ContextSwitches++;
 
    /* Load data from switch frame */
    Pcr->NtTib.ExceptionList = SwitchFrame->ExceptionList;
 
    /* DPCs shouldn't be active */
    if (Pcr->PrcbData.DpcRoutineActive)
    {
        /* Crash the machine */
        KeBugCheckEx(ATTEMPTED_SWITCH_FROM_DPC,
                     (ULONG_PTR)OldThread,
                     (ULONG_PTR)NewThread,
                     (ULONG_PTR)OldThread->InitialStack,
                     0);
    }
 
    /* Kernel APCs may be pending */
    if (NewThread->ApcState.KernelApcPending)
    {
        /* Are APCs enabled? */
        if (!NewThread->SpecialApcDisable)
        {
            /* Request APC delivery */
            if (SwitchFrame->ApcBypassDisable)
                HalRequestSoftwareInterrupt(APC_LEVEL);
            else
                return TRUE;
        }
    }
 
    /* Return stating that no kernel APCs are pending*/
    return FALSE;
}

KiSwitchThreads()

VOID FASTCALL KiSwitchThreads	(	IN PKTHREAD	OldThread,
		IN PKTHREAD	NewThread
	)

KiThreadStartup()

VOID NTAPI KiThreadStartup

(

VOID

)

Definition at line 63 of file thrdini.c.

{
    PKTRAP_FRAME TrapFrame;
    PKSTART_FRAME StartFrame;
    PKUINIT_FRAME InitFrame;
 
    /* Get the start and trap frames */
    InitFrame = KeGetCurrentThread()->KernelStack;
    StartFrame = &InitFrame->StartFrame;
    TrapFrame = &InitFrame->TrapFrame;
 
    /* Lower to APC level */
    KfLowerIrql(APC_LEVEL);
 
    /* Call the system routine */
    StartFrame->SystemRoutine(StartFrame->StartRoutine, StartFrame->StartContext);
 
    /* If we returned, we better be a user thread */
    if (!StartFrame->UserThread)
    {
        KeBugCheck(NO_USER_MODE_CONTEXT);
    }
 
    /* Exit to user-mode */
    KiServiceExit2(TrapFrame);
}

Referenced by KiInitializeContextThread().