semevent-r0drv-darwin.cpp revision e0e7da0420be1398d23ffa9953686d3a43619abd
/* $Id$ */
/** @file
* IPRT - Single Release Event Semaphores, Ring-0 Driver, Darwin.
*/
/*
* Copyright (C) 2006-2010 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-darwin-kernel.h"
#include "internal/iprt.h"
#include <iprt/semaphore.h>
#include <iprt/assert.h>
#include <iprt/asm.h>
#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
# include <iprt/asm-amd64-x86.h>
#endif
#include <iprt/err.h>
#include <iprt/list.h>
#include <iprt/lockvalidator.h>
#include <iprt/mem.h>
#include <iprt/mp.h>
#include <iprt/thread.h>
#include <iprt/time.h>
#include "internal/magics.h"
/*******************************************************************************
* Structures and Typedefs *
*******************************************************************************/
/**
* Waiter entry. Lives on the stack.
*/
typedef struct RTSEMEVENTDARWINENTRY
{
/** The list node. */
RTLISTNODE Node;
/** Flag set when waking up the thread by signal or destroy. */
bool volatile fWokenUp;
} RTSEMEVENTDARWINENTRY;
/** Pointer to waiter entry. */
typedef RTSEMEVENTDARWINENTRY *PRTSEMEVENTDARWINENTRY;
/**
* Darwin event semaphore.
*/
typedef struct RTSEMEVENTINTERNAL
{
/** Magic value (RTSEMEVENT_MAGIC). */
uint32_t volatile u32Magic;
/** Reference counter. */
uint32_t volatile cRefs;
/** Set if there are blocked threads. */
bool volatile fHaveBlockedThreads;
/** Set if the event object is signaled. */
bool volatile fSignaled;
/** List of waiting and woken up threads. */
RTLISTNODE WaitList;
/** The spinlock protecting us. */
lck_spin_t *pSpinlock;
} RTSEMEVENTINTERNAL, *PRTSEMEVENTINTERNAL;
RTDECL(int) RTSemEventCreate(PRTSEMEVENT phEventSem)
{
return RTSemEventCreateEx(phEventSem, 0 /*fFlags*/, NIL_RTLOCKVALCLASS, NULL);
}
RTDECL(int) RTSemEventCreateEx(PRTSEMEVENT phEventSem, uint32_t fFlags, RTLOCKVALCLASS hClass, const char *pszNameFmt, ...)
{
AssertCompile(sizeof(RTSEMEVENTINTERNAL) > sizeof(void *));
AssertReturn(!(fFlags & ~RTSEMEVENT_FLAGS_NO_LOCK_VAL), VERR_INVALID_PARAMETER);
AssertPtrReturn(phEventSem, VERR_INVALID_POINTER);
RT_ASSERT_PREEMPTIBLE();
PRTSEMEVENTINTERNAL pThis = (PRTSEMEVENTINTERNAL)RTMemAlloc(sizeof(*pThis));
if (pThis)
{
pThis->u32Magic = RTSEMEVENT_MAGIC;
pThis->cRefs = 1;
pThis->fHaveBlockedThreads = false;
pThis->fSignaled = false;
RTListInit(&pThis->WaitList);
Assert(g_pDarwinLockGroup);
pThis->pSpinlock = lck_spin_alloc_init(g_pDarwinLockGroup, LCK_ATTR_NULL);
if (pThis->pSpinlock)
{
*phEventSem = pThis;
return VINF_SUCCESS;
}
pThis->u32Magic = 0;
RTMemFree(pThis);
}
return VERR_NO_MEMORY;
}
/**
* Retain a reference to the semaphore.
*
* @param pThis The semaphore.
*/
DECLINLINE(void) rtR0SemEventDarwinRetain(PRTSEMEVENTINTERNAL pThis)
{
uint32_t cRefs = ASMAtomicIncU32(&pThis->cRefs);
Assert(cRefs && cRefs < 100000);
}
/**
* Release a reference, destroy the thing if necessary.
*
* @param pThis The semaphore.
*/
DECLINLINE(void) rtR0SemEventDarwinRelease(PRTSEMEVENTINTERNAL pThis)
{
if (RT_UNLIKELY(ASMAtomicDecU32(&pThis->cRefs) == 0))
{
Assert(pThis->u32Magic != RTSEMEVENT_MAGIC);
lck_spin_destroy(pThis->pSpinlock, g_pDarwinLockGroup);
RTMemFree(pThis);
}
}
RTDECL(int) RTSemEventDestroy(RTSEMEVENT hEventSem)
{
PRTSEMEVENTINTERNAL pThis = hEventSem;
if (pThis == NIL_RTSEMEVENT)
return VINF_SUCCESS;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertMsgReturn(pThis->u32Magic == RTSEMEVENT_MAGIC, ("pThis=%p u32Magic=%#x\n", pThis, pThis->u32Magic), VERR_INVALID_HANDLE);
RT_ASSERT_INTS_ON();
lck_spin_lock(pThis->pSpinlock);
ASMAtomicWriteU32(&pThis->u32Magic, ~RTSEMEVENT_MAGIC); /* make the handle invalid */
ASMAtomicWriteBool(&pThis->fSignaled, false);
/* abort waiting threads. */
PRTSEMEVENTDARWINENTRY pWaiter;
RTListForEach(&pThis->WaitList, pWaiter, RTSEMEVENTDARWINENTRY, Node)
{
pWaiter->fWokenUp = true;
thread_wakeup_prim((event_t)pWaiter, FALSE /* all threads */, THREAD_RESTART);
}
lck_spin_unlock(pThis->pSpinlock);
rtR0SemEventDarwinRelease(pThis);
return VINF_SUCCESS;
}
RTDECL(int) RTSemEventSignal(RTSEMEVENT hEventSem)
{
PRTSEMEVENTINTERNAL pThis = (PRTSEMEVENTINTERNAL)hEventSem;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertMsgReturn(pThis->u32Magic == RTSEMEVENT_MAGIC,
("pThis=%p u32Magic=%#x\n", pThis, pThis->u32Magic),
VERR_INVALID_HANDLE);
RT_ASSERT_PREEMPT_CPUID_VAR();
RT_ASSERT_INTS_ON();
rtR0SemEventDarwinRetain(pThis);
/** @todo should probably disable interrupts here... update
* semspinmutex-r0drv-generic.c when done. */
lck_spin_lock(pThis->pSpinlock);
/*
* Wake up one thread.
*/
ASMAtomicWriteBool(&pThis->fSignaled, true);
PRTSEMEVENTDARWINENTRY pWaiter;
RTListForEach(&pThis->WaitList, pWaiter, RTSEMEVENTDARWINENTRY, Node)
{
if (!pWaiter->fWokenUp)
{
pWaiter->fWokenUp = true;
thread_wakeup_prim((event_t)pWaiter, FALSE /* all threads */, THREAD_AWAKENED);
ASMAtomicWriteBool(&pThis->fSignaled, false);
break;
}
}
lck_spin_unlock(pThis->pSpinlock);
rtR0SemEventDarwinRelease(pThis);
RT_ASSERT_PREEMPT_CPUID();
return VINF_SUCCESS;
}
/**
* Worker for RTSemEventWaitEx and RTSemEventWaitExDebug.
*
* @returns VBox status code.
* @param pThis The event semaphore.
* @param fFlags See RTSemEventWaitEx.
* @param uTimeout See RTSemEventWaitEx.
* @param pSrcPos The source code position of the wait.
*/
static int rtR0SemEventDarwinWait(PRTSEMEVENTINTERNAL pThis, uint32_t fFlags, uint64_t uTimeout,
PCRTLOCKVALSRCPOS pSrcPos)
{
/*
* Validate the input.
*/
AssertPtrReturn(pThis, VERR_INVALID_PARAMETER);
AssertMsgReturn(pThis->u32Magic == RTSEMEVENT_MAGIC, ("%p u32Magic=%RX32\n", pThis, pThis->u32Magic), VERR_INVALID_PARAMETER);
AssertReturn(RTSEMWAIT_FLAGS_ARE_VALID(fFlags), VERR_INVALID_PARAMETER);
rtR0SemEventDarwinRetain(pThis);
lck_spin_lock(pThis->pSpinlock);
/*
* In the signaled state?
*/
int rc;
if (ASMAtomicCmpXchgBool(&pThis->fSignaled, false, true))
rc = VINF_SUCCESS;
else
{
/*
* We have to wait. So, we'll need to convert the timeout and figure
* out if it's indefinite or not.
*/
uint64_t uNsAbsTimeout = 1;
if (!(fFlags & RTSEMWAIT_FLAGS_INDEFINITE))
{
if (fFlags & RTSEMWAIT_FLAGS_MILLISECS)
uTimeout = uTimeout < UINT64_MAX / UINT32_C(1000000) * UINT32_C(1000000)
? uTimeout * UINT32_C(1000000)
: UINT64_MAX;
if (uTimeout == UINT64_MAX)
fFlags |= RTSEMWAIT_FLAGS_INDEFINITE;
else
{
uint64_t u64Now;
if (fFlags & RTSEMWAIT_FLAGS_RELATIVE)
{
if (uTimeout != 0)
{
u64Now = RTTimeSystemNanoTS();
uNsAbsTimeout = u64Now + uTimeout;
if (uNsAbsTimeout < u64Now) /* overflow */
fFlags |= RTSEMWAIT_FLAGS_INDEFINITE;
}
}
else
{
uNsAbsTimeout = uTimeout;
u64Now = RTTimeSystemNanoTS();
uTimeout = u64Now < uTimeout ? uTimeout - u64Now : 0;
}
}
}
if ( !(fFlags & RTSEMWAIT_FLAGS_INDEFINITE)
&& uTimeout == 0)
{
/*
* Poll call, we already checked the condition above so no need to
* wait for anything.
*/
rc = VERR_TIMEOUT;
}
else
{
RTSEMEVENTDARWINENTRY Waiter;
Waiter.fWokenUp = false;
RTListAppend(&pThis->WaitList, &Waiter.Node);
for (;;)
{
/*
* Do the actual waiting.
*/
ASMAtomicWriteBool(&pThis->fHaveBlockedThreads, true);
wait_interrupt_t fInterruptible = fFlags & RTSEMWAIT_FLAGS_INTERRUPTIBLE ? THREAD_ABORTSAFE : THREAD_UNINT;
wait_result_t rcWait;
if (fFlags & RTSEMWAIT_FLAGS_INDEFINITE)
rcWait = lck_spin_sleep(pThis->pSpinlock, LCK_SLEEP_DEFAULT, (event_t)&Waiter, fInterruptible);
else
{
uint64_t u64AbsTime;
nanoseconds_to_absolutetime(uNsAbsTimeout, &u64AbsTime);
rcWait = lck_spin_sleep_deadline(pThis->pSpinlock, LCK_SLEEP_DEFAULT,
(event_t)&Waiter, fInterruptible, u64AbsTime);
}
/*
* Deal with the wait result.
*/
if (RT_LIKELY(pThis->u32Magic == RTSEMEVENT_MAGIC))
{
switch (rcWait)
{
case THREAD_AWAKENED:
if (RT_LIKELY(Waiter.fWokenUp))
rc = VINF_SUCCESS;
else if (fFlags & RTSEMWAIT_FLAGS_INTERRUPTIBLE)
rc = VERR_INTERRUPTED;
else
continue; /* Seen this happen after fork/exec/something. */
break;
case THREAD_TIMED_OUT:
Assert(!(fFlags & RTSEMWAIT_FLAGS_INDEFINITE));
rc = !Waiter.fWokenUp ? VERR_TIMEOUT : VINF_SUCCESS;
break;
case THREAD_INTERRUPTED:
Assert(fInterruptible != THREAD_UNINT);
rc = !Waiter.fWokenUp ? VERR_INTERRUPTED : VINF_SUCCESS;
break;
case THREAD_RESTART:
AssertMsg(pThis->u32Magic == ~RTSEMEVENT_MAGIC, ("%#x\n", pThis->u32Magic));
rc = VERR_SEM_DESTROYED;
break;
default:
AssertMsgFailed(("rcWait=%d\n", rcWait));
rc = VERR_INTERNAL_ERROR_3;
break;
}
}
else
rc = VERR_SEM_DESTROYED;
break;
}
RTListNodeRemove(&Waiter.Node);
}
}
lck_spin_unlock(pThis->pSpinlock);
rtR0SemEventDarwinRelease(pThis);
return rc;
}
#undef RTSemEventWaitEx
RTDECL(int) RTSemEventWaitEx(RTSEMEVENT hEventSem, uint32_t fFlags, uint64_t uTimeout)
{
#ifndef RTSEMEVENT_STRICT
return rtR0SemEventDarwinWait(hEventSem, fFlags, uTimeout, NULL);
#else
RTLOCKVALSRCPOS SrcPos = RTLOCKVALSRCPOS_INIT_NORMAL_API();
return rtR0SemEventDarwinWait(hEventSem, fFlags, uTimeout, &SrcPos);
#endif
}
RTDECL(int) RTSemEventWaitExDebug(RTSEMEVENT hEventSem, uint32_t fFlags, uint64_t uTimeout,
RTHCUINTPTR uId, RT_SRC_POS_DECL)
{
RTLOCKVALSRCPOS SrcPos = RTLOCKVALSRCPOS_INIT_DEBUG_API();
return rtR0SemEventDarwinWait(hEventSem, fFlags, uTimeout, &SrcPos);
}
RTDECL(uint32_t) RTSemEventGetResolution(void)
{
uint32_t cNs = absolutetime_to_nanoseconds(1);
if (cNs == 0)
cNs = 1;
return cNs;
}