RTMpOnPair-generic.cpp revision 4ba3599814cc63307fe48a5d47394ae7c6f391e6
/* $Id$ */
/** @file
* IPRT - RTMpOnPair, generic implementation using RTMpOnAll.
*/
/*
* Copyright (C) 2015 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 "internal/iprt.h"
#include <iprt/mp.h>
#include <iprt/asm.h>
#include <iprt/assert.h>
#include <iprt/err.h>
/*******************************************************************************
* Structures and Typedefs *
*******************************************************************************/
/**
* Argument package for the generic RTMpOnPair implemenetation.
*/
typedef struct RTMPONPAIRGENERIC
{
RTCPUID idCpu1;
RTCPUID idCpu2;
PFNRTMPWORKER pfnWorker;
void *pvUser1;
void *pvUser2;
/** Count of how many CPUs actually showed up. */
uint32_t volatile cPresent;
} RTMPONPAIRGENERIC;
/** Pointer to the an argument package for the generic RTMpOnPair
* implemenation. */
typedef RTMPONPAIRGENERIC *PRTMPONPAIRGENERIC;
/**
* @callback_method_impl{FNRTMPWORKER,
* Used by RTMpOnPair to call the worker on the two specified CPUs.}
*/
static DECLCALLBACK(void) rtMpOnPairGenericWorker(RTCPUID idCpu, void *pvUser1, void *pvUser2)
{
PRTMPONPAIRGENERIC pArgs = (PRTMPONPAIRGENERIC)pvUser1;
/*
* Only the two choosen CPUs should call the worker function, count how
* many of them that showed up.
*/
if ( idCpu == pArgs->idCpu1
|| idCpu == pArgs->idCpu2)
{
ASMAtomicIncU32(&pArgs->cPresent);
pArgs->pfnWorker(idCpu, pArgs->pvUser1, pArgs->pvUser2);
}
}
RTDECL(int) RTMpOnPair(RTCPUID idCpu1, RTCPUID idCpu2, uint32_t fFlags, PFNRTMPWORKER pfnWorker, void *pvUser1, void *pvUser2)
{
int rc;
AssertReturn(idCpu1 != idCpu2, VERR_INVALID_PARAMETER);
AssertReturn(!(fFlags & RTMPON_F_VALID_MASK), VERR_INVALID_FLAGS);
if ((fFlags & RTMPON_F_CONCURRENT_EXEC) && !RTMpOnAllIsConcurrentSafe())
return VERR_NOT_SUPPORTED;
/*
* Check that both CPUs are online before doing the broadcast call.
*/
if ( RTMpIsCpuOnline(idCpu1)
&& RTMpIsCpuOnline(idCpu2))
{
RTMPONPAIRGENERIC Args;
Args.idCpu1 = idCpu1;
Args.idCpu2 = idCpu2;
Args.pfnWorker = pfnWorker;
Args.pvUser1 = pvUser1;
Args.pvUser2 = pvUser2;
Args.cPresent = 0;
rc = RTMpOnAll(rtMpOnPairGenericWorker, &Args, pvUser2);
if (RT_SUCCESS(rc))
{
/*
* Let's see if both of the CPUs showed up.
*/
if (RT_LIKELY(Args.cPresent == 2))
{ /* likely */ }
else if (Args.cPresent == 0)
rc = VERR_CPU_OFFLINE;
else if (Args.cPresent == 1)
rc = VERR_NOT_ALL_CPUS_SHOWED;
else
{
rc = VERR_CPU_IPE_1;
AssertMsgFailed(("cPresent=%#x\n", Args.cPresent));
}
}
}
/*
* A CPU must be present to be considered just offline.
*/
else if ( RTMpIsCpuPresent(idCpu1)
&& RTMpIsCpuPresent(idCpu2))
rc = VERR_CPU_OFFLINE;
else
rc = VERR_CPU_NOT_FOUND;
return rc;
}
RTDECL(bool) RTMpOnPairIsConcurrentExecSupported(void)
{
return RTMpOnAllIsConcurrentSafe();
}