windows-nt/Source/XPSP1/NT/base/ntos/ke/debug.c
2020-09-26 16:20:57 +08:00

547 lines
11 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*++
Copyright (c) 1989-1993 Microsoft Corporation
Module Name:
stubs.c
Abstract:
This module implements kernel debugger synchronization routines.
Author:
Ken Reneris (kenr) 30-Aug-1990
Environment:
Kernel mode only.
Revision History:
--*/
#include "ki.h"
#define IDBG 1
#define FrozenState(a) (a & 0xF)
// state
#define RUNNING 0x00
#define TARGET_FROZEN 0x02
#define TARGET_THAW 0x03
#define FREEZE_OWNER 0x04
// flags (bits)
#define FREEZE_ACTIVE 0x20
//
// Define local storage to save the old IRQL.
//
KIRQL KiOldIrql;
#ifndef NT_UP
PKPRCB KiFreezeOwner;
#endif
BOOLEAN
KeFreezeExecution (
IN PKTRAP_FRAME TrapFrame,
IN PKEXCEPTION_FRAME ExceptionFrame
)
/*++
Routine Description:
This function freezes the execution of all other processors in the host
configuration and then returns to the caller.
Arguments:
TrapFrame - Supplies a pointer to a trap frame that describes the
trap.
ExceptionFrame - Supplies a pointer to an exception frame that
describes the trap.
Return Value:
Previous interrupt enable.
--*/
{
BOOLEAN Enable;
#if !defined(NT_UP)
BOOLEAN Flag;
PKPRCB Prcb;
KAFFINITY TargetSet;
ULONG BitNumber;
KIRQL OldIrql;
#if IDBG
ULONG Count = 30000;
#endif
#endif
//
// Disable interrupts.
//
Enable = KeDisableInterrupts();
KiFreezeFlag = FREEZE_FROZEN;
#if !defined(NT_UP)
//
// Raise IRQL to HIGH_LEVEL.
//
KeRaiseIrql(HIGH_LEVEL, &OldIrql);
if (FrozenState(KeGetCurrentPrcb()->IpiFrozen) == FREEZE_OWNER) {
//
// This processor already owns the freeze lock.
// Return without trying to re-acquire lock or without
// trying to IPI the other processors again
//
return Enable;
}
//
// Try to acquire the KiFreezeExecutionLock before sending the request.
// To prevent deadlock from occurring, we need to accept and process
// incoming FreexeExecution requests while we are waiting to acquire
// the FreezeExecutionFlag.
//
while (KeTryToAcquireSpinLockAtDpcLevel(&KiFreezeExecutionLock) == FALSE) {
//
// FreezeExecutionLock is busy. Another processor may be trying
// to IPI us - go service any IPI.
//
KeEnableInterrupts(Enable);
Flag = KiIpiServiceRoutine((PVOID)TrapFrame, (PVOID)ExceptionFrame);
KeDisableInterrupts();
#if IDBG
if (Flag != FALSE) {
Count = 30000;
continue;
}
KeStallExecutionProcessor (100);
if (!Count--) {
Count = 30000;
if (KeTryToAcquireSpinLockAtDpcLevel(&KiFreezeLockBackup) == TRUE) {
KiFreezeFlag |= FREEZE_BACKUP;
break;
}
}
#endif
}
//
// After acquiring the lock flag, we send Freeze request to each processor
// in the system (other than us) and wait for it to become frozen.
//
Prcb = KeGetCurrentPrcb(); // Do this after spinlock is acquired.
TargetSet = KeActiveProcessors & ~(AFFINITY_MASK(Prcb->Number));
if (TargetSet) {
#if IDBG
Count = 400;
#endif
KiFreezeOwner = Prcb;
Prcb->IpiFrozen = FREEZE_OWNER | FREEZE_ACTIVE;
Prcb->SkipTick = TRUE;
KiIpiSend((KAFFINITY) TargetSet, IPI_FREEZE);
while (TargetSet != 0) {
KeFindFirstSetLeftAffinity(TargetSet, &BitNumber);
ClearMember(BitNumber, TargetSet);
Prcb = KiProcessorBlock[BitNumber];
#if IDBG
while (Prcb->IpiFrozen != TARGET_FROZEN) {
if (Count == 0) {
KiFreezeFlag |= FREEZE_SKIPPED_PROCESSOR;
break;
}
KeStallExecutionProcessor (10000);
Count--;
}
#else
while (Prcb->IpiFrozen != TARGET_FROZEN) {
KeYieldProcessor();
}
#endif
}
}
//
// Save the old IRQL and return whether interrupts were previous enabled.
//
KiOldIrql = OldIrql;
#endif // !defined(NT_UP)
return Enable;
}
VOID
KiFreezeTargetExecution (
IN PKTRAP_FRAME TrapFrame,
IN PKEXCEPTION_FRAME ExceptionFrame
)
/*++
Routine Description:
This function freezes the execution of the current running processor.
If a trapframe is supplied to current state is saved into the prcb
for the debugger.
Arguments:
TrapFrame - Supplies a pointer to the trap frame that describes the
trap.
ExceptionFrame - Supplies a pointer to the exception frame that
describes the trap.
Return Value:
None.
--*/
{
#if !defined(NT_UP)
KIRQL OldIrql;
PKPRCB Prcb;
BOOLEAN Enable;
KCONTINUE_STATUS Status;
EXCEPTION_RECORD ExceptionRecord;
Enable = KeDisableInterrupts();
KeRaiseIrql(HIGH_LEVEL, &OldIrql);
Prcb = KeGetCurrentPrcb();
Prcb->IpiFrozen = TARGET_FROZEN;
Prcb->SkipTick = TRUE;
if (TrapFrame != NULL) {
KiSaveProcessorState(TrapFrame, ExceptionFrame);
}
//
// Sweep the data cache in case this is a system crash and the bug
// check code is attempting to write a crash dump file.
//
KeSweepCurrentDcache();
//
// Wait for person requesting us to freeze to
// clear our frozen flag
//
while (FrozenState(Prcb->IpiFrozen) == TARGET_FROZEN) {
if (Prcb->IpiFrozen & FREEZE_ACTIVE) {
//
// This processor has been made the active processor
//
if (TrapFrame) {
RtlZeroMemory (&ExceptionRecord, sizeof ExceptionRecord);
ExceptionRecord.ExceptionCode = STATUS_WAKE_SYSTEM_DEBUGGER;
ExceptionRecord.ExceptionRecord = &ExceptionRecord;
ExceptionRecord.ExceptionAddress =
(PVOID)CONTEXT_TO_PROGRAM_COUNTER (&Prcb->ProcessorState.ContextFrame);
Status = (KiDebugSwitchRoutine) (
&ExceptionRecord,
&Prcb->ProcessorState.ContextFrame,
FALSE
);
} else {
Status = ContinueError;
}
//
// If status is anything other then, continue with next
// processor then reselect master
//
if (Status != ContinueNextProcessor) {
Prcb->IpiFrozen &= ~FREEZE_ACTIVE;
KiFreezeOwner->IpiFrozen |= FREEZE_ACTIVE;
}
}
KeYieldProcessor();
}
if (TrapFrame != NULL) {
KiRestoreProcessorState(TrapFrame, ExceptionFrame);
}
Prcb->IpiFrozen = RUNNING;
KeFlushCurrentTb();
KeSweepCurrentIcache();
KeLowerIrql(OldIrql);
KeEnableInterrupts(Enable);
#endif // !define(NT_UP)
return;
}
KCONTINUE_STATUS
KeSwitchFrozenProcessor (
IN ULONG ProcessorNumber
)
{
#if !defined(NT_UP)
PKPRCB TargetPrcb, CurrentPrcb;
//
// If Processor number is out of range, reselect current processor
//
if (ProcessorNumber >= (ULONG) KeNumberProcessors) {
return ContinueProcessorReselected;
}
TargetPrcb = KiProcessorBlock[ProcessorNumber];
CurrentPrcb = KeGetCurrentPrcb();
//
// Move active flag to correct processor.
//
CurrentPrcb->IpiFrozen &= ~FREEZE_ACTIVE;
TargetPrcb->IpiFrozen |= FREEZE_ACTIVE;
//
// If this processor is frozen in KiFreezeTargetExecution, return to it
//
if (FrozenState(CurrentPrcb->IpiFrozen) == TARGET_FROZEN) {
return ContinueNextProcessor;
}
//
// This processor must be FREEZE_OWNER, wait to be reselected as the
// active processor
//
if (FrozenState(CurrentPrcb->IpiFrozen) != FREEZE_OWNER) {
return ContinueError;
}
while (!(CurrentPrcb->IpiFrozen & FREEZE_ACTIVE)) {
KeYieldProcessor();
}
#endif // !defined(NT_UP)
//
// Reselect this processor
//
return ContinueProcessorReselected;
}
VOID
KeThawExecution (
IN BOOLEAN Enable
)
/*++
Routine Description:
This function thaws the execution of all other processors in the host
configuration and then returns to the caller. It is intended for use by
the kernel debugger.
Arguments:
Enable - Supplies the previous interrupt enable that is to be restored
after having thawed the execution of all other processors.
Return Value:
None.
--*/
{
#if !defined(NT_UP)
KIRQL OldIrql;
KAFFINITY TargetSet;
ULONG BitNumber;
ULONG Flag;
PKPRCB Prcb;
//
// Before releasing FreezeExecutionLock clear any all targets IpiFrozen
// flag.
//
KeGetCurrentPrcb()->IpiFrozen = RUNNING;
TargetSet = KeActiveProcessors & ~(AFFINITY_MASK(KeGetCurrentPrcb()->Number));
while (TargetSet != 0) {
KeFindFirstSetLeftAffinity(TargetSet, &BitNumber);
ClearMember(BitNumber, TargetSet);
Prcb = KiProcessorBlock[BitNumber];
#if IDBG
//
// If the target processor was not forzen, then don't wait
// for target to unfreeze.
//
if (FrozenState(Prcb->IpiFrozen) != TARGET_FROZEN) {
Prcb->IpiFrozen = RUNNING;
continue;
}
#endif
Prcb->IpiFrozen = TARGET_THAW;
while (Prcb->IpiFrozen == TARGET_THAW) {
KeYieldProcessor();
}
}
//
// Capture the previous IRQL before releasing the freeze lock.
//
OldIrql = KiOldIrql;
#if IDBG
Flag = KiFreezeFlag;
KiFreezeFlag = 0;
if ((Flag & FREEZE_BACKUP) != 0) {
KiReleaseSpinLock(&KiFreezeLockBackup);
} else {
KiReleaseSpinLock(&KiFreezeExecutionLock);
}
#else
KiFreezeFlag = 0;
KiReleaseSpinLock(&KiFreezeExecutionLock);
#endif
#endif // !defined (NT_UP)
//
// Flush the current TB, instruction cache, and data cache.
//
KeFlushCurrentTb();
KeSweepCurrentIcache();
KeSweepCurrentDcache();
//
// Lower IRQL and restore interrupt enable
//
#if !defined(NT_UP)
KeLowerIrql(OldIrql);
#endif
KeEnableInterrupts(Enable);
return;
}
VOID
KiPollFreezeExecution(
VOID
)
/*++
Routine Description:
This routine is called from code that is spinning with interrupts
disabled, waiting for something to happen, when there is some
(possibly extremely small) chance that that thing will not happen
because a system freeze has been initiated.
N.B. Interrupts are disabled.
Arguments:
None.
Return Value:
None.
--*/
{
//
// Check to see if a freeze is pending for this processor.
//
PKPRCB Prcb = KeGetCurrentPrcb();
if ((Prcb->RequestSummary & IPI_FREEZE) != 0) {
//
// Clear the freeze request and freeze this processor.
//
InterlockedExchangeAdd((PLONG)&Prcb->RequestSummary, -(IPI_FREEZE));
KiFreezeTargetExecution(NULL, NULL);
} else {
//
// No freeze pending, assume this processor is spinning.
//
KeYieldProcessor();
}
}