spinlock-r0drv-nt.cpp revision 9ce0c902e5adeaa0a1b7d9b31770b86d4eeec02a
/* $Id$ */
/** @file
* IPRT - Spinlocks, Ring-0 Driver, NT.
*/
/*
* Copyright (C) 2006-2012 Oracle Corporation
*
* This file is part of VirtualBox Open Source Edition (OSE), as
* available from http://www.virtualbox.org. This file is free software;
* you can redistribute it and/or modify it under the terms of the GNU
* General Public License (GPL) as published by the Free Software
* Foundation, in version 2 as it comes in the "COPYING" file of the
* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
*
* The contents of this file may alternatively be used under the terms
* of the Common Development and Distribution License Version 1.0
* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
* VirtualBox OSE distribution, in which case the provisions of the
* CDDL are applicable instead of those of the GPL.
*
* You may elect to license modified versions of this file under the
* terms and conditions of either the GPL or the CDDL or both.
*/
/*******************************************************************************
* Header Files *
*******************************************************************************/
#include "the-nt-kernel.h"
#include <iprt/spinlock.h>
#include <iprt/asm.h>
#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
# include <iprt/asm-amd64-x86.h>
#endif
#include <iprt/assert.h>
#include <iprt/err.h>
#include <iprt/mem.h>
#include "internal/magics.h"
/*******************************************************************************
* Defined Constants And Macros *
*******************************************************************************/
/** Apply the NoIrq hack if defined. */
#define RTSPINLOCK_NT_HACK_NOIRQ
#ifdef RTSPINLOCK_NT_HACK_NOIRQ
/** Indicates that the spinlock is taken. */
# define RTSPINLOCK_NT_HACK_NOIRQ_TAKEN UINT32(0x00c0ffee)
/** Indicates that the spinlock is taken. */
# define RTSPINLOCK_NT_HACK_NOIRQ_FREE UINT32(0xfe0000fe)
#endif
/*******************************************************************************
* Structures and Typedefs *
*******************************************************************************/
/**
* Wrapper for the KSPIN_LOCK type.
*/
typedef struct RTSPINLOCKINTERNAL
{
/** Spinlock magic value (RTSPINLOCK_MAGIC). */
uint32_t volatile u32Magic;
#ifdef RTSPINLOCK_NT_HACK_NOIRQ
/** Spinlock hack. */
uint32_t volatile u32Hack;
#endif
/** The saved IRQL. */
KIRQL volatile SavedIrql;
/** The saved interrupt flag. */
uint32_t volatile fIntSaved;
/** The spinlock creation flags. */
uint32_t fFlags;
/** The NT spinlock structure. */
KSPIN_LOCK Spinlock;
} RTSPINLOCKINTERNAL, *PRTSPINLOCKINTERNAL;
RTDECL(int) RTSpinlockCreate(PRTSPINLOCK pSpinlock, uint32_t fFlags, const char *pszName)
{
AssertReturn(fFlags == RTSPINLOCK_FLAGS_INTERRUPT_SAFE || fFlags == RTSPINLOCK_FLAGS_INTERRUPT_UNSAFE, VERR_INVALID_PARAMETER);
/*
* Allocate.
*/
Assert(sizeof(RTSPINLOCKINTERNAL) > sizeof(void *));
PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)RTMemAlloc(sizeof(*pThis));
if (!pThis)
return VERR_NO_MEMORY;
/*
* Initialize & return.
*/
pThis->u32Magic = RTSPINLOCK_MAGIC;
#ifdef RTSPINLOCK_NT_HACK_NOIRQ
pThis->u32Hack = RTSPINLOCK_NT_HACK_NOIRQ_FREE;
#endif
pThis->SavedIrql = 0;
pThis->fIntSaved = 0;
pThis->fFlags = fFlags;
KeInitializeSpinLock(&pThis->Spinlock);
*pSpinlock = pThis;
return VINF_SUCCESS;
}
RTDECL(int) RTSpinlockDestroy(RTSPINLOCK Spinlock)
{
/*
* Validate input.
*/
PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock;
if (!pThis)
return VERR_INVALID_PARAMETER;
if (pThis->u32Magic != RTSPINLOCK_MAGIC)
{
AssertMsgFailed(("Invalid spinlock %p magic=%#x\n", pThis, pThis->u32Magic));
return VERR_INVALID_PARAMETER;
}
ASMAtomicIncU32(&pThis->u32Magic);
RTMemFree(pThis);
return VINF_SUCCESS;
}
RTDECL(void) RTSpinlockAcquire(RTSPINLOCK Spinlock)
{
PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock;
AssertMsg(pThis && pThis->u32Magic == RTSPINLOCK_MAGIC, ("magic=%#x\n", pThis->u32Magic));
KIRQL SavedIrql;
if (pThis->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE)
{
#ifndef RTSPINLOCK_NT_HACK_NOIRQ
uint32_t fIntSaved = ASMGetFlags();
ASMIntDisable();
KeAcquireSpinLock(&pThis->Spinlock, &SavedIrql);
#else
SavedIrql = KeGetCurrentIrql();
if (SavedIrql < DISPATCH_LEVEL)
{
KeRaiseIrql(DISPATCH_LEVEL, &SavedIrql);
Assert(SavedIrql < DISPATCH_LEVEL);
}
uint32_t fIntSaved = ASMGetFlags();
ASMIntDisable();
if (!ASMAtomicCmpXchgU32(&pThis->u32Hack, RTSPINLOCK_NT_HACK_NOIRQ_TAKEN, RTSPINLOCK_NT_HACK_NOIRQ_FREE))
{
while (!ASMAtomicCmpXchgU32(&pThis->u32Hack, RTSPINLOCK_NT_HACK_NOIRQ_TAKEN, RTSPINLOCK_NT_HACK_NOIRQ_FREE))
ASMNopPause();
}
pThis->fIntSaved = fIntSaved;
#endif
}
else
KeAcquireSpinLock(&pThis->Spinlock, &SavedIrql);
pThis->SavedIrql = SavedIrql;
}
RTDECL(void) RTSpinlockRelease(RTSPINLOCK Spinlock)
{
PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock;
AssertMsg(pThis && pThis->u32Magic == RTSPINLOCK_MAGIC, ("magic=%#x\n", pThis->u32Magic));
KIRQL SavedIrql = pThis->SavedIrql;
if (pThis->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE)
{
uint32_t fIntSaved = pThis->fIntSaved;
pThis->fIntSaved = 0;
#ifndef RTSPINLOCK_NT_HACK_NOIRQ
KeReleaseSpinLock(&pThis->Spinlock, SavedIrql);
ASMSetFlags(fIntSaved);
#else
Assert(pThis->u32Hack == RTSPINLOCK_NT_HACK_NOIRQ_TAKEN);
ASMAtomicWriteU32(&pThis->u32Hack, RTSPINLOCK_NT_HACK_NOIRQ_FREE);
ASMSetFlags(fIntSaved);
if (SavedIrql < DISPATCH_LEVEL)
KeLowerIrql(SavedIrql);
#endif
}
else
KeReleaseSpinLock(&pThis->Spinlock, SavedIrql);
}
RTDECL(void) RTSpinlockReleaseNoInts(RTSPINLOCK Spinlock)
{
#if 1
if (RT_UNLIKELY(!(Spinlock->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE)))
RTAssertMsg2("RTSpinlockReleaseNoInts: %p (magic=%#x)\n", Spinlock, Spinlock->u32Magic);
#else
AssertRelease(Spinlock->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE);
#endif
RTSpinlockRelease(Spinlock);
}