VMEmt.cpp revision 571c90a734400801da973f986190fac9fc5efd0d
/* $Id$ */
/** @file
* VM - Virtual Machine, The Emulation Thread.
*/
/*
* Copyright (C) 2006-2007 Sun Microsystems, Inc.
*
* 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.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 USA or visit http://www.sun.com if you need
* additional information or have any questions.
*/
/*******************************************************************************
* Header Files *
*******************************************************************************/
#define LOG_GROUP LOG_GROUP_VM
#include <VBox/tm.h>
#include <VBox/dbgf.h>
#include <VBox/em.h>
#include <VBox/pdmapi.h>
#include <VBox/rem.h>
#include <VBox/tm.h>
#include "VMInternal.h"
#include <VBox/vm.h>
#include <VBox/uvm.h>
#include <VBox/err.h>
#include <VBox/log.h>
#include <iprt/assert.h>
#include <iprt/asm.h>
#include <iprt/semaphore.h>
#include <iprt/string.h>
#include <iprt/thread.h>
#include <iprt/time.h>
/*******************************************************************************
* Internal Functions *
*******************************************************************************/
int vmR3EmulationThreadWithId(RTTHREAD ThreadSelf, PUVMCPU pUVCpu, VMCPUID idCpu);
/**
* The emulation thread main function.
*
* @returns Thread exit code.
* @param ThreadSelf The handle to the executing thread.
* @param pvArgs Pointer to the user mode per-VCpu structure (UVMPCU).
*/
DECLCALLBACK(int) vmR3EmulationThread(RTTHREAD ThreadSelf, void *pvArgs)
{
PUVMCPU pUVCpu = (PUVMCPU)pvArgs;
return vmR3EmulationThreadWithId(ThreadSelf, pUVCpu, pUVCpu->idCpu);
}
/**
* The emulation thread main function, with Virtual CPU ID for debugging.
*
* @returns Thread exit code.
* @param ThreadSelf The handle to the executing thread.
* @param pUVCpu Pointer to the user mode per-VCpu structure.
* @param idCpu The virtual CPU ID, for backtrace purposes.
*/
int vmR3EmulationThreadWithId(RTTHREAD ThreadSelf, PUVMCPU pUVCpu, VMCPUID idCpu)
{
PUVM pUVM = pUVCpu->pUVM;
int rc;
AssertReleaseMsg(VALID_PTR(pUVM) && pUVM->u32Magic == UVM_MAGIC,
("Invalid arguments to the emulation thread!\n"));
rc = RTTlsSet(pUVM->vm.s.idxTLS, pUVCpu);
AssertReleaseMsgRCReturn(rc, ("RTTlsSet %x failed with %Rrc\n", pUVM->vm.s.idxTLS, rc), rc);
/*
* The request loop.
*/
rc = VINF_SUCCESS;
Log(("vmR3EmulationThread: Emulation thread starting the days work... Thread=%#x pUVM=%p\n", ThreadSelf, pUVM));
VMSTATE enmBefore = VMSTATE_CREATED; /* (only used for logging atm.) */
for (;;)
{
/*
* During early init there is no pVM, so make a special path
* for that to keep things clearly separate.
*/
if (!pUVM->pVM)
{
/*
* Check for termination first.
*/
if (pUVM->vm.s.fTerminateEMT)
{
rc = VINF_EM_TERMINATE;
break;
}
/*
* Only the first VCPU may initialize the VM during early init
* and must therefore service all VMCPUID_ANY requests.
* See also VMR3Create
*/
if ( pUVM->vm.s.pReqs
&& pUVCpu->idCpu == 0)
{
/*
* Service execute in any EMT request.
*/
rc = VMR3ReqProcessU(pUVM, VMCPUID_ANY);
Log(("vmR3EmulationThread: Req rc=%Rrc, VM state %d -> %d\n", rc, enmBefore, pUVM->pVM ? pUVM->pVM->enmVMState : VMSTATE_CREATING));
}
else if (pUVCpu->vm.s.pReqs)
{
/*
* Service execute in specific EMT request.
*/
rc = VMR3ReqProcessU(pUVM, pUVCpu->idCpu);
Log(("vmR3EmulationThread: Req (cpu=%u) rc=%Rrc, VM state %d -> %d\n", pUVCpu->idCpu, rc, enmBefore, pUVM->pVM ? pUVM->pVM->enmVMState : VMSTATE_CREATING));
}
else
{
/*
* Nothing important is pending, so wait for something.
*/
rc = VMR3WaitU(pUVCpu);
if (RT_FAILURE(rc))
{
AssertLogRelMsgFailed(("VMR3WaitU failed with %Rrc\n", rc));
break;
}
}
}
else
{
/*
* Pending requests which needs servicing?
*
* We check for state changes in addition to status codes when
* servicing requests. (Look after the ifs.)
*/
PVM pVM = pUVM->pVM;
enmBefore = pVM->enmVMState;
if ( VM_FF_ISSET(pVM, VM_FF_TERMINATE)
|| pUVM->vm.s.fTerminateEMT)
{
rc = VINF_EM_TERMINATE;
break;
}
if (VM_FF_ISPENDING(pVM, VM_FF_EMT_RENDEZVOUS))
VMMR3EmtRendezvousFF(pVM, &pVM->aCpus[idCpu]);
if (pUVM->vm.s.pReqs)
{
/*
* Service execute in any EMT request.
*/
rc = VMR3ReqProcessU(pUVM, VMCPUID_ANY);
Log(("vmR3EmulationThread: Req rc=%Rrc, VM state %d -> %d\n", rc, enmBefore, pVM->enmVMState));
}
else if (pUVCpu->vm.s.pReqs)
{
/*
* Service execute in specific EMT request.
*/
rc = VMR3ReqProcessU(pUVM, pUVCpu->idCpu);
Log(("vmR3EmulationThread: Req (cpu=%u) rc=%Rrc, VM state %d -> %d\n", pUVCpu->idCpu, rc, enmBefore, pVM->enmVMState));
}
else if (VM_FF_ISSET(pVM, VM_FF_DBGF))
{
/*
* Service the debugger request.
*/
rc = DBGFR3VMMForcedAction(pVM);
Log(("vmR3EmulationThread: Dbg rc=%Rrc, VM state %d -> %d\n", rc, enmBefore, pVM->enmVMState));
}
else if (VM_FF_TESTANDCLEAR(pVM, VM_FF_RESET_BIT))
{
/*
* Service a delayed reset request.
*/
rc = VMR3Reset(pVM);
VM_FF_CLEAR(pVM, VM_FF_RESET);
Log(("vmR3EmulationThread: Reset rc=%Rrc, VM state %d -> %d\n", rc, enmBefore, pVM->enmVMState));
}
else
{
/*
* Nothing important is pending, so wait for something.
*/
rc = VMR3WaitU(pUVCpu);
if (RT_FAILURE(rc))
{
AssertLogRelMsgFailed(("VMR3WaitU failed with %Rrc\n", rc));
break;
}
}
/*
* Check for termination requests, these have extremely high priority.
*/
if ( rc == VINF_EM_TERMINATE
|| pUVM->vm.s.fTerminateEMT
|| ( pUVM->pVM /* pVM may have become invalid by now. */
&& VM_FF_ISSET(pUVM->pVM, VM_FF_TERMINATE)))
break;
}
/*
* Some requests (both VMR3Req* and the DBGF) can potentially resume
* or start the VM, in that case we'll get a change in VM status
* indicating that we're now running.
*/
if ( RT_SUCCESS(rc)
&& pUVM->pVM)
{
PVM pVM = pUVM->pVM;
PVMCPU pVCpu = &pVM->aCpus[idCpu];
if ( pVM->enmVMState == VMSTATE_RUNNING
&& VMCPUSTATE_IS_STARTED(VMCPU_GET_STATE(pVCpu)))
{
rc = EMR3ExecuteVM(pVM, pVCpu);
Log(("vmR3EmulationThread: EMR3ExecuteVM() -> rc=%Rrc, enmVMState=%d\n", rc, pVM->enmVMState));
if ( EMGetState(pVCpu) == EMSTATE_GURU_MEDITATION
&& pVM->enmVMState == VMSTATE_RUNNING)
vmR3SetState(pVM, VMSTATE_GURU_MEDITATION);
}
}
} /* forever */
/*
* Exiting.
*/
Log(("vmR3EmulationThread: Terminating emulation thread! Thread=%#x pUVM=%p rc=%Rrc enmBefore=%d enmVMState=%d\n",
ThreadSelf, pUVM, rc, enmBefore, pUVM->pVM ? pUVM->pVM->enmVMState : VMSTATE_TERMINATED));
if (pUVM->vm.s.fEMTDoesTheCleanup)
{
Log(("vmR3EmulationThread: executing delayed Destroy\n"));
Assert(pUVM->pVM);
vmR3Destroy(pUVM->pVM);
vmR3DestroyFinalBitFromEMT(pUVM);
}
else
{
vmR3DestroyFinalBitFromEMT(pUVM);
pUVCpu->vm.s.NativeThreadEMT = NIL_RTNATIVETHREAD;
}
Log(("vmR3EmulationThread: EMT is terminated.\n"));
return rc;
}
/**
* Gets the name of a halt method.
*
* @returns Pointer to a read only string.
* @param enmMethod The method.
*/
static const char *vmR3GetHaltMethodName(VMHALTMETHOD enmMethod)
{
switch (enmMethod)
{
case VMHALTMETHOD_BOOTSTRAP: return "bootstrap";
case VMHALTMETHOD_DEFAULT: return "default";
case VMHALTMETHOD_OLD: return "old";
case VMHALTMETHOD_1: return "method1";
//case VMHALTMETHOD_2: return "method2";
case VMHALTMETHOD_GLOBAL_1: return "global1";
default: return "unknown";
}
}
/**
* The old halt loop.
*/
static DECLCALLBACK(int) vmR3HaltOldDoHalt(PUVMCPU pUVCpu, const uint32_t fMask, uint64_t /* u64Now*/)
{
/*
* Halt loop.
*/
PVM pVM = pUVCpu->pVM;
PVMCPU pVCpu = pUVCpu->pVCpu;
int rc = VINF_SUCCESS;
ASMAtomicWriteBool(&pUVCpu->vm.s.fWait, true);
//unsigned cLoops = 0;
for (;;)
{
/*
* Work the timers and check if we can exit.
* The poll call gives us the ticks left to the next event in
* addition to perhaps set an FF.
*/
STAM_REL_PROFILE_START(&pUVCpu->vm.s.StatHaltTimers, b);
TMR3TimerQueuesDo(pVM);
STAM_REL_PROFILE_STOP(&pUVCpu->vm.s.StatHaltTimers, b);
if ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_HALTED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, fMask))
break;
uint64_t u64NanoTS;
TMTimerPollGIP(pVM, pVCpu, &u64NanoTS);
if ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_HALTED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, fMask))
break;
/*
* Wait for a while. Someone will wake us up or interrupt the call if
* anything needs our attention.
*/
if (u64NanoTS < 50000)
{
//RTLogPrintf("u64NanoTS=%RI64 cLoops=%d spin\n", u64NanoTS, cLoops++);
/* spin */;
}
else
{
VMMR3YieldStop(pVM);
//uint64_t u64Start = RTTimeNanoTS();
if (u64NanoTS < 870000) /* this is a bit speculative... works fine on linux. */
{
//RTLogPrintf("u64NanoTS=%RI64 cLoops=%d yield", u64NanoTS, cLoops++);
STAM_REL_PROFILE_START(&pUVCpu->vm.s.StatHaltYield, a);
RTThreadYield(); /* this is the best we can do here */
STAM_REL_PROFILE_STOP(&pUVCpu->vm.s.StatHaltYield, a);
}
else if (u64NanoTS < 2000000)
{
//RTLogPrintf("u64NanoTS=%RI64 cLoops=%d sleep 1ms", u64NanoTS, cLoops++);
STAM_REL_PROFILE_START(&pUVCpu->vm.s.StatHaltBlock, a);
rc = RTSemEventWait(pUVCpu->vm.s.EventSemWait, 1);
STAM_REL_PROFILE_STOP(&pUVCpu->vm.s.StatHaltBlock, a);
}
else
{
//RTLogPrintf("u64NanoTS=%RI64 cLoops=%d sleep %dms", u64NanoTS, cLoops++, (uint32_t)RT_MIN((u64NanoTS - 500000) / 1000000, 15));
STAM_REL_PROFILE_START(&pUVCpu->vm.s.StatHaltBlock, a);
rc = RTSemEventWait(pUVCpu->vm.s.EventSemWait, RT_MIN((u64NanoTS - 1000000) / 1000000, 15));
STAM_REL_PROFILE_STOP(&pUVCpu->vm.s.StatHaltBlock, a);
}
//uint64_t u64Slept = RTTimeNanoTS() - u64Start;
//RTLogPrintf(" -> rc=%Rrc in %RU64 ns / %RI64 ns delta\n", rc, u64Slept, u64NanoTS - u64Slept);
}
if (rc == VERR_TIMEOUT)
rc = VINF_SUCCESS;
else if (RT_FAILURE(rc))
{
AssertRC(rc != VERR_INTERRUPTED);
AssertMsgFailed(("RTSemEventWait->%Rrc\n", rc));
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fTerminateEMT, true);
VM_FF_SET(pVM, VM_FF_TERMINATE);
rc = VERR_INTERNAL_ERROR;
break;
}
}
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fWait, false);
return rc;
}
/**
* Initialize the configuration of halt method 1 & 2.
*
* @return VBox status code. Failure on invalid CFGM data.
* @param pVM The VM handle.
*/
static int vmR3HaltMethod12ReadConfigU(PUVM pUVM)
{
/*
* The defaults.
*/
#if 1 /* DEBUGGING STUFF - REMOVE LATER */
pUVM->vm.s.Halt.Method12.u32LagBlockIntervalDivisorCfg = 4;
pUVM->vm.s.Halt.Method12.u32MinBlockIntervalCfg = 2*1000000;
pUVM->vm.s.Halt.Method12.u32MaxBlockIntervalCfg = 75*1000000;
pUVM->vm.s.Halt.Method12.u32StartSpinningCfg = 30*1000000;
pUVM->vm.s.Halt.Method12.u32StopSpinningCfg = 20*1000000;
#else
pUVM->vm.s.Halt.Method12.u32LagBlockIntervalDivisorCfg = 4;
pUVM->vm.s.Halt.Method12.u32MinBlockIntervalCfg = 5*1000000;
pUVM->vm.s.Halt.Method12.u32MaxBlockIntervalCfg = 200*1000000;
pUVM->vm.s.Halt.Method12.u32StartSpinningCfg = 20*1000000;
pUVM->vm.s.Halt.Method12.u32StopSpinningCfg = 2*1000000;
#endif
/*
* Query overrides.
*
* I don't have time to bother with niceities such as invalid value checks
* here right now. sorry.
*/
PCFGMNODE pCfg = CFGMR3GetChild(CFGMR3GetRoot(pUVM->pVM), "/VMM/HaltedMethod1");
if (pCfg)
{
uint32_t u32;
if (RT_SUCCESS(CFGMR3QueryU32(pCfg, "LagBlockIntervalDivisor", &u32)))
pUVM->vm.s.Halt.Method12.u32LagBlockIntervalDivisorCfg = u32;
if (RT_SUCCESS(CFGMR3QueryU32(pCfg, "MinBlockInterval", &u32)))
pUVM->vm.s.Halt.Method12.u32MinBlockIntervalCfg = u32;
if (RT_SUCCESS(CFGMR3QueryU32(pCfg, "MaxBlockInterval", &u32)))
pUVM->vm.s.Halt.Method12.u32MaxBlockIntervalCfg = u32;
if (RT_SUCCESS(CFGMR3QueryU32(pCfg, "StartSpinning", &u32)))
pUVM->vm.s.Halt.Method12.u32StartSpinningCfg = u32;
if (RT_SUCCESS(CFGMR3QueryU32(pCfg, "StopSpinning", &u32)))
pUVM->vm.s.Halt.Method12.u32StopSpinningCfg = u32;
LogRel(("HaltedMethod1 config: %d/%d/%d/%d/%d\n",
pUVM->vm.s.Halt.Method12.u32LagBlockIntervalDivisorCfg,
pUVM->vm.s.Halt.Method12.u32MinBlockIntervalCfg,
pUVM->vm.s.Halt.Method12.u32MaxBlockIntervalCfg,
pUVM->vm.s.Halt.Method12.u32StartSpinningCfg,
pUVM->vm.s.Halt.Method12.u32StopSpinningCfg));
}
return VINF_SUCCESS;
}
/**
* Initialize halt method 1.
*
* @return VBox status code.
* @param pUVM Pointer to the user mode VM structure.
*/
static DECLCALLBACK(int) vmR3HaltMethod1Init(PUVM pUVM)
{
return vmR3HaltMethod12ReadConfigU(pUVM);
}
/**
* Method 1 - Block whenever possible, and when lagging behind
* switch to spinning for 10-30ms with occational blocking until
* the lag has been eliminated.
*/
static DECLCALLBACK(int) vmR3HaltMethod1Halt(PUVMCPU pUVCpu, const uint32_t fMask, uint64_t u64Now)
{
PUVM pUVM = pUVCpu->pUVM;
PVMCPU pVCpu = pUVCpu->pVCpu;
PVM pVM = pUVCpu->pVM;
/*
* To simplify things, we decide up-front whether we should switch to spinning or
* not. This makes some ASSUMPTIONS about the cause of the spinning (PIT/RTC/PCNet)
* and that it will generate interrupts or other events that will cause us to exit
* the halt loop.
*/
bool fBlockOnce = false;
bool fSpinning = false;
uint32_t u32CatchUpPct = TMVirtualSyncGetCatchUpPct(pVM);
if (u32CatchUpPct /* non-zero if catching up */)
{
if (pUVCpu->vm.s.Halt.Method12.u64StartSpinTS)
{
fSpinning = TMVirtualSyncGetLag(pVM) >= pUVM->vm.s.Halt.Method12.u32StopSpinningCfg;
if (fSpinning)
{
uint64_t u64Lag = TMVirtualSyncGetLag(pVM);
fBlockOnce = u64Now - pUVCpu->vm.s.Halt.Method12.u64LastBlockTS
> RT_MAX(pUVM->vm.s.Halt.Method12.u32MinBlockIntervalCfg,
RT_MIN(u64Lag / pUVM->vm.s.Halt.Method12.u32LagBlockIntervalDivisorCfg,
pUVM->vm.s.Halt.Method12.u32MaxBlockIntervalCfg));
}
else
{
//RTLogRelPrintf("Stopped spinning (%u ms)\n", (u64Now - pUVCpu->vm.s.Halt.Method12.u64StartSpinTS) / 1000000);
pUVCpu->vm.s.Halt.Method12.u64StartSpinTS = 0;
}
}
else
{
fSpinning = TMVirtualSyncGetLag(pVM) >= pUVM->vm.s.Halt.Method12.u32StartSpinningCfg;
if (fSpinning)
pUVCpu->vm.s.Halt.Method12.u64StartSpinTS = u64Now;
}
}
else if (pUVCpu->vm.s.Halt.Method12.u64StartSpinTS)
{
//RTLogRelPrintf("Stopped spinning (%u ms)\n", (u64Now - pUVCpu->vm.s.Halt.Method12.u64StartSpinTS) / 1000000);
pUVCpu->vm.s.Halt.Method12.u64StartSpinTS = 0;
}
/*
* Halt loop.
*/
int rc = VINF_SUCCESS;
ASMAtomicWriteBool(&pUVCpu->vm.s.fWait, true);
unsigned cLoops = 0;
for (;; cLoops++)
{
/*
* Work the timers and check if we can exit.
*/
STAM_REL_PROFILE_START(&pUVCpu->vm.s.StatHaltTimers, b);
TMR3TimerQueuesDo(pVM);
STAM_REL_PROFILE_STOP(&pUVCpu->vm.s.StatHaltTimers, b);
if ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_HALTED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, fMask))
break;
/*
* Estimate time left to the next event.
*/
uint64_t u64NanoTS;
TMTimerPollGIP(pVM, pVCpu, &u64NanoTS);
if ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_HALTED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, fMask))
break;
/*
* Block if we're not spinning and the interval isn't all that small.
*/
if ( ( !fSpinning
|| fBlockOnce)
#if 1 /* DEBUGGING STUFF - REMOVE LATER */
&& u64NanoTS >= 100000) /* 0.100 ms */
#else
&& u64NanoTS >= 250000) /* 0.250 ms */
#endif
{
const uint64_t Start = pUVCpu->vm.s.Halt.Method12.u64LastBlockTS = RTTimeNanoTS();
VMMR3YieldStop(pVM);
uint32_t cMilliSecs = RT_MIN(u64NanoTS / 1000000, 15);
if (cMilliSecs <= pUVCpu->vm.s.Halt.Method12.cNSBlockedTooLongAvg)
cMilliSecs = 1;
else
cMilliSecs -= pUVCpu->vm.s.Halt.Method12.cNSBlockedTooLongAvg;
//RTLogRelPrintf("u64NanoTS=%RI64 cLoops=%3d sleep %02dms (%7RU64) ", u64NanoTS, cLoops, cMilliSecs, u64NanoTS);
STAM_REL_PROFILE_START(&pUVCpu->vm.s.StatHaltBlock, a);
rc = RTSemEventWait(pUVCpu->vm.s.EventSemWait, cMilliSecs);
STAM_REL_PROFILE_STOP(&pUVCpu->vm.s.StatHaltBlock, a);
if (rc == VERR_TIMEOUT)
rc = VINF_SUCCESS;
else if (RT_FAILURE(rc))
{
AssertRC(rc != VERR_INTERRUPTED);
AssertMsgFailed(("RTSemEventWait->%Rrc\n", rc));
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fTerminateEMT, true);
VM_FF_SET(pVM, VM_FF_TERMINATE);
rc = VERR_INTERNAL_ERROR;
break;
}
/*
* Calc the statistics.
* Update averages every 16th time, and flush parts of the history every 64th time.
*/
const uint64_t Elapsed = RTTimeNanoTS() - Start;
pUVCpu->vm.s.Halt.Method12.cNSBlocked += Elapsed;
if (Elapsed > u64NanoTS)
pUVCpu->vm.s.Halt.Method12.cNSBlockedTooLong += Elapsed - u64NanoTS;
pUVCpu->vm.s.Halt.Method12.cBlocks++;
if (!(pUVCpu->vm.s.Halt.Method12.cBlocks & 0xf))
{
pUVCpu->vm.s.Halt.Method12.cNSBlockedTooLongAvg = pUVCpu->vm.s.Halt.Method12.cNSBlockedTooLong / pUVCpu->vm.s.Halt.Method12.cBlocks;
if (!(pUVCpu->vm.s.Halt.Method12.cBlocks & 0x3f))
{
pUVCpu->vm.s.Halt.Method12.cNSBlockedTooLong = pUVCpu->vm.s.Halt.Method12.cNSBlockedTooLongAvg * 0x40;
pUVCpu->vm.s.Halt.Method12.cBlocks = 0x40;
}
}
//RTLogRelPrintf(" -> %7RU64 ns / %7RI64 ns delta%s\n", Elapsed, Elapsed - u64NanoTS, fBlockOnce ? " (block once)" : "");
/*
* Clear the block once flag if we actually blocked.
*/
if ( fBlockOnce
&& Elapsed > 100000 /* 0.1 ms */)
fBlockOnce = false;
}
}
//if (fSpinning) RTLogRelPrintf("spun for %RU64 ns %u loops; lag=%RU64 pct=%d\n", RTTimeNanoTS() - u64Now, cLoops, TMVirtualSyncGetLag(pVM), u32CatchUpPct);
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fWait, false);
return rc;
}
/**
* Initialize the global 1 halt method.
*
* @return VBox status code.
* @param pUVM Pointer to the user mode VM structure.
*/
static DECLCALLBACK(int) vmR3HaltGlobal1Init(PUVM pUVM)
{
return VINF_SUCCESS;
}
/**
* The global 1 halt method - Block in GMM (ring-0) and let it
* try take care of the global scheduling of EMT threads.
*/
static DECLCALLBACK(int) vmR3HaltGlobal1Halt(PUVMCPU pUVCpu, const uint32_t fMask, uint64_t u64Now)
{
PUVM pUVM = pUVCpu->pUVM;
PVMCPU pVCpu = pUVCpu->pVCpu;
PVM pVM = pUVCpu->pVM;
Assert(VMMGetCpu(pVM) == pVCpu);
/*
* Halt loop.
*/
int rc = VINF_SUCCESS;
ASMAtomicWriteBool(&pUVCpu->vm.s.fWait, true);
unsigned cLoops = 0;
for (;; cLoops++)
{
/*
* Work the timers and check if we can exit.
*/
STAM_REL_PROFILE_START(&pUVCpu->vm.s.StatHaltTimers, b);
TMR3TimerQueuesDo(pVM);
STAM_REL_PROFILE_STOP(&pUVCpu->vm.s.StatHaltTimers, b);
if ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_HALTED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, fMask))
break;
/*
* Estimate time left to the next event.
*/
uint64_t u64Delta;
uint64_t u64GipTime = TMTimerPollGIP(pVM, pVCpu, &u64Delta);
if ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_HALTED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, fMask))
break;
/*
* Block if we're not spinning and the interval isn't all that small.
*/
if (u64Delta > 50000 /* 0.050ms */)
{
VMMR3YieldStop(pVM);
if ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_HALTED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, fMask))
break;
//RTLogRelPrintf("u64NanoTS=%RI64 cLoops=%3d sleep %02dms (%7RU64) ", u64NanoTS, cLoops, cMilliSecs, u64NanoTS);
STAM_REL_PROFILE_START(&pUVCpu->vm.s.StatHaltBlock, c);
rc = SUPR3CallVMMR0Ex(pVM->pVMR0, pVCpu->idCpu, VMMR0_DO_GVMM_SCHED_HALT, u64GipTime, NULL);
STAM_REL_PROFILE_STOP(&pUVCpu->vm.s.StatHaltBlock, c);
if (rc == VERR_INTERRUPTED)
rc = VINF_SUCCESS;
else if (RT_FAILURE(rc))
{
AssertMsgFailed(("VMMR0_DO_GVMM_SCHED_HALT->%Rrc\n", rc));
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fTerminateEMT, true);
VM_FF_SET(pVM, VM_FF_TERMINATE);
rc = VERR_INTERNAL_ERROR;
break;
}
}
/*
* When spinning call upon the GVMM and do some wakups once
* in a while, it's not like we're actually busy or anything.
*/
else if (!(cLoops & 0x1fff))
{
STAM_REL_PROFILE_START(&pUVCpu->vm.s.StatHaltYield, d);
rc = SUPR3CallVMMR0Ex(pVM->pVMR0, pVCpu->idCpu, VMMR0_DO_GVMM_SCHED_POLL, false /* don't yield */, NULL);
STAM_REL_PROFILE_STOP(&pUVCpu->vm.s.StatHaltYield, d);
}
}
//if (fSpinning) RTLogRelPrintf("spun for %RU64 ns %u loops; lag=%RU64 pct=%d\n", RTTimeNanoTS() - u64Now, cLoops, TMVirtualSyncGetLag(pVM), u32CatchUpPct);
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fWait, false);
return rc;
}
/**
* The global 1 halt method - VMR3Wait() worker.
*
* @returns VBox status code.
* @param pUVCpu Pointer to the user mode VMCPU structure.
*/
static DECLCALLBACK(int) vmR3HaltGlobal1Wait(PUVMCPU pUVCpu)
{
ASMAtomicWriteBool(&pUVCpu->vm.s.fWait, true);
PVM pVM = pUVCpu->pUVM->pVM;
PVMCPU pVCpu = VMMGetCpu(pVM);
Assert(pVCpu->idCpu == pUVCpu->idCpu);
int rc = VINF_SUCCESS;
for (;;)
{
/*
* Check Relevant FFs.
*/
if ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_SUSPENDED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, VMCPU_FF_EXTERNAL_SUSPENDED_MASK))
break;
/*
* Wait for a while. Someone will wake us up or interrupt the call if
* anything needs our attention.
*/
rc = SUPR3CallVMMR0Ex(pVM->pVMR0, pVCpu->idCpu, VMMR0_DO_GVMM_SCHED_HALT, RTTimeNanoTS() + 1000000000 /* +1s */, NULL);
if (rc == VERR_INTERRUPTED)
rc = VINF_SUCCESS;
else if (RT_FAILURE(rc))
{
AssertMsgFailed(("RTSemEventWait->%Rrc\n", rc));
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fTerminateEMT, true);
VM_FF_SET(pVM, VM_FF_TERMINATE);
rc = VERR_INTERNAL_ERROR;
break;
}
}
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fWait, false);
return rc;
}
/**
* The global 1 halt method - VMR3NotifyFF() worker.
*
* @param pUVCpu Pointer to the user mode VMCPU structure.
* @param fFlags Notification flags, VMNOTIFYFF_FLAGS_*.
*/
static DECLCALLBACK(void) vmR3HaltGlobal1NotifyCpuFF(PUVMCPU pUVCpu, uint32_t fFlags)
{
if (pUVCpu->vm.s.fWait)
{
int rc = SUPR3CallVMMR0Ex(pUVCpu->pVM->pVMR0, pUVCpu->idCpu, VMMR0_DO_GVMM_SCHED_WAKE_UP, 0, NULL);
AssertRC(rc);
}
else if ( ( (fFlags & VMNOTIFYFF_FLAGS_POKE)
|| !(fFlags & VMNOTIFYFF_FLAGS_DONE_REM))
&& pUVCpu->pVCpu)
{
VMCPUSTATE enmState = VMCPU_GET_STATE(pUVCpu->pVCpu);
if (enmState == VMCPUSTATE_STARTED_EXEC)
{
if (fFlags & VMNOTIFYFF_FLAGS_POKE)
{
int rc = SUPR3CallVMMR0Ex(pUVCpu->pVM->pVMR0, pUVCpu->idCpu, VMMR0_DO_GVMM_SCHED_POKE, 0, NULL);
AssertRC(rc);
}
}
else if (enmState == VMCPUSTATE_STARTED_EXEC_REM)
{
if (!(fFlags & VMNOTIFYFF_FLAGS_DONE_REM))
REMR3NotifyFF(pUVCpu->pVM);
}
}
}
/**
* Bootstrap VMR3Wait() worker.
*
* @returns VBox status code.
* @param pUVMCPU Pointer to the user mode VMCPU structure.
*/
static DECLCALLBACK(int) vmR3BootstrapWait(PUVMCPU pUVCpu)
{
PUVM pUVM = pUVCpu->pUVM;
ASMAtomicWriteBool(&pUVCpu->vm.s.fWait, true);
int rc = VINF_SUCCESS;
for (;;)
{
/*
* Check Relevant FFs.
*/
if (pUVM->vm.s.pReqs) /* global requests pending? */
break;
if (pUVCpu->vm.s.pReqs) /* local requests pending? */
break;
if ( pUVCpu->pVM
&& ( VM_FF_ISPENDING(pUVCpu->pVM, VM_FF_EXTERNAL_SUSPENDED_MASK)
|| VMCPU_FF_ISPENDING(VMMGetCpu(pUVCpu->pVM), VMCPU_FF_EXTERNAL_SUSPENDED_MASK)
)
)
break;
if (pUVCpu->vm.s.fTerminateEMT)
break;
/*
* Wait for a while. Someone will wake us up or interrupt the call if
* anything needs our attention.
*/
rc = RTSemEventWait(pUVCpu->vm.s.EventSemWait, 1000);
if (rc == VERR_TIMEOUT)
rc = VINF_SUCCESS;
else if (RT_FAILURE(rc))
{
AssertMsgFailed(("RTSemEventWait->%Rrc\n", rc));
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fTerminateEMT, true);
if (pUVCpu->pVM)
VM_FF_SET(pUVCpu->pVM, VM_FF_TERMINATE);
rc = VERR_INTERNAL_ERROR;
break;
}
}
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fWait, false);
return rc;
}
/**
* Bootstrap VMR3NotifyFF() worker.
*
* @param pUVCpu Pointer to the user mode VMCPU structure.
* @param fFlags Notification flags, VMNOTIFYFF_FLAGS_*.
*/
static DECLCALLBACK(void) vmR3BootstrapNotifyCpuFF(PUVMCPU pUVCpu, uint32_t fFlags)
{
if (pUVCpu->vm.s.fWait)
{
int rc = RTSemEventSignal(pUVCpu->vm.s.EventSemWait);
AssertRC(rc);
}
NOREF(fFlags);
}
/**
* Default VMR3Wait() worker.
*
* @returns VBox status code.
* @param pUVMCPU Pointer to the user mode VMCPU structure.
*/
static DECLCALLBACK(int) vmR3DefaultWait(PUVMCPU pUVCpu)
{
ASMAtomicWriteBool(&pUVCpu->vm.s.fWait, true);
PVM pVM = pUVCpu->pVM;
PVMCPU pVCpu = pUVCpu->pVCpu;
int rc = VINF_SUCCESS;
for (;;)
{
/*
* Check Relevant FFs.
*/
if ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_SUSPENDED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, VMCPU_FF_EXTERNAL_SUSPENDED_MASK))
break;
/*
* Wait for a while. Someone will wake us up or interrupt the call if
* anything needs our attention.
*/
rc = RTSemEventWait(pUVCpu->vm.s.EventSemWait, 1000);
if (rc == VERR_TIMEOUT)
rc = VINF_SUCCESS;
else if (RT_FAILURE(rc))
{
AssertMsgFailed(("RTSemEventWait->%Rrc\n", rc));
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fTerminateEMT, true);
VM_FF_SET(pVM, VM_FF_TERMINATE);
rc = VERR_INTERNAL_ERROR;
break;
}
}
ASMAtomicUoWriteBool(&pUVCpu->vm.s.fWait, false);
return rc;
}
/**
* Default VMR3NotifyFF() worker.
*
* @param pUVCpu Pointer to the user mode VMCPU structure.
* @param fFlags Notification flags, VMNOTIFYFF_FLAGS_*.
*/
static DECLCALLBACK(void) vmR3DefaultNotifyCpuFF(PUVMCPU pUVCpu, uint32_t fFlags)
{
if (pUVCpu->vm.s.fWait)
{
int rc = RTSemEventSignal(pUVCpu->vm.s.EventSemWait);
AssertRC(rc);
}
else if ( !(fFlags & VMNOTIFYFF_FLAGS_DONE_REM)
&& pUVCpu->pVCpu
&& pUVCpu->pVCpu->enmState == VMCPUSTATE_STARTED_EXEC_REM)
REMR3NotifyFF(pUVCpu->pVM);
}
/**
* Array with halt method descriptors.
* VMINT::iHaltMethod contains an index into this array.
*/
static const struct VMHALTMETHODDESC
{
/** The halt method id. */
VMHALTMETHOD enmHaltMethod;
/** The init function for loading config and initialize variables. */
DECLR3CALLBACKMEMBER(int, pfnInit,(PUVM pUVM));
/** The term function. */
DECLR3CALLBACKMEMBER(void, pfnTerm,(PUVM pUVM));
/** The VMR3WaitHaltedU function. */
DECLR3CALLBACKMEMBER(int, pfnHalt,(PUVMCPU pUVCpu, const uint32_t fMask, uint64_t u64Now));
/** The VMR3WaitU function. */
DECLR3CALLBACKMEMBER(int, pfnWait,(PUVMCPU pUVCpu));
/** The VMR3NotifyCpuFFU function. */
DECLR3CALLBACKMEMBER(void, pfnNotifyCpuFF,(PUVMCPU pUVCpu, uint32_t fFlags));
/** The VMR3NotifyGlobalFFU function. */
DECLR3CALLBACKMEMBER(void, pfnNotifyGlobalFF,(PUVM pUVM, uint32_t fFlags));
} g_aHaltMethods[] =
{
{ VMHALTMETHOD_BOOTSTRAP, NULL, NULL, NULL, vmR3BootstrapWait, vmR3BootstrapNotifyCpuFF, NULL },
{ VMHALTMETHOD_OLD, NULL, NULL, vmR3HaltOldDoHalt, vmR3DefaultWait, vmR3DefaultNotifyCpuFF, NULL },
{ VMHALTMETHOD_1, vmR3HaltMethod1Init, NULL, vmR3HaltMethod1Halt, vmR3DefaultWait, vmR3DefaultNotifyCpuFF, NULL },
{ VMHALTMETHOD_GLOBAL_1, vmR3HaltGlobal1Init, NULL, vmR3HaltGlobal1Halt, vmR3HaltGlobal1Wait, vmR3HaltGlobal1NotifyCpuFF, NULL },
};
/**
* Notify the emulation thread (EMT) about pending Forced Action (FF).
*
* This function is called by thread other than EMT to make
* sure EMT wakes up and promptly service an FF request.
*
* @param pUVM Pointer to the user mode VM structure.
* @param fFlags Notification flags, VMNOTIFYFF_FLAGS_*.
*/
VMMR3DECL(void) VMR3NotifyGlobalFFU(PUVM pUVM, uint32_t fFlags)
{
LogFlow(("VMR3NotifyGlobalFFU:\n"));
uint32_t iHaldMethod = pUVM->vm.s.iHaltMethod;
if (g_aHaltMethods[iHaldMethod].pfnNotifyGlobalFF) /** @todo make mandatory. */
g_aHaltMethods[iHaldMethod].pfnNotifyGlobalFF(pUVM, fFlags);
else
for (VMCPUID iCpu = 0; iCpu < pUVM->cCpus; iCpu++)
g_aHaltMethods[iHaldMethod].pfnNotifyCpuFF(&pUVM->aCpus[iCpu], fFlags);
}
/**
* Notify the emulation thread (EMT) about pending Forced Action (FF).
*
* This function is called by thread other than EMT to make
* sure EMT wakes up and promptly service an FF request.
*
* @param pUVM Pointer to the user mode VM structure.
* @param fFlags Notification flags, VMNOTIFYFF_FLAGS_*.
*/
VMMR3DECL(void) VMR3NotifyCpuFFU(PUVMCPU pUVCpu, uint32_t fFlags)
{
PUVM pUVM = pUVCpu->pUVM;
LogFlow(("VMR3NotifyCpuFFU:\n"));
g_aHaltMethods[pUVM->vm.s.iHaltMethod].pfnNotifyCpuFF(pUVCpu, fFlags);
}
/**
* Halted VM Wait.
* Any external event will unblock the thread.
*
* @returns VINF_SUCCESS unless a fatal error occurred. In the latter
* case an appropriate status code is returned.
* @param pVM VM handle.
* @param pVCpu VMCPU handle.
* @param fIgnoreInterrupts If set the VM_FF_INTERRUPT flags is ignored.
* @thread The emulation thread.
*/
VMMR3DECL(int) VMR3WaitHalted(PVM pVM, PVMCPU pVCpu, bool fIgnoreInterrupts)
{
LogFlow(("VMR3WaitHalted: fIgnoreInterrupts=%d\n", fIgnoreInterrupts));
/*
* Check Relevant FFs.
*/
const uint32_t fMask = !fIgnoreInterrupts
? VMCPU_FF_EXTERNAL_HALTED_MASK
: VMCPU_FF_EXTERNAL_HALTED_MASK & ~(VMCPU_FF_INTERRUPT_APIC | VMCPU_FF_INTERRUPT_PIC);
if ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_HALTED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, fMask))
{
LogFlow(("VMR3WaitHalted: returns VINF_SUCCESS (FF %#x FFCPU %#x)\n", pVM->fGlobalForcedActions, pVCpu->fLocalForcedActions));
return VINF_SUCCESS;
}
/*
* The yielder is suspended while we're halting, while TM might have clock(s) running
* only at certain times and need to be notified..
*/
if (pVCpu->idCpu == 0)
VMMR3YieldSuspend(pVM);
TMNotifyStartOfHalt(pVCpu);
/*
* Record halt averages for the last second.
*/
PUVMCPU pUVCpu = pVCpu->pUVCpu;
uint64_t u64Now = RTTimeNanoTS();
int64_t off = u64Now - pUVCpu->vm.s.u64HaltsStartTS;
if (off > 1000000000)
{
if (off > _4G || !pUVCpu->vm.s.cHalts)
{
pUVCpu->vm.s.HaltInterval = 1000000000 /* 1 sec */;
pUVCpu->vm.s.HaltFrequency = 1;
}
else
{
pUVCpu->vm.s.HaltInterval = (uint32_t)off / pUVCpu->vm.s.cHalts;
pUVCpu->vm.s.HaltFrequency = ASMMultU64ByU32DivByU32(pUVCpu->vm.s.cHalts, 1000000000, (uint32_t)off);
}
pUVCpu->vm.s.u64HaltsStartTS = u64Now;
pUVCpu->vm.s.cHalts = 0;
}
pUVCpu->vm.s.cHalts++;
/*
* Do the halt.
*/
Assert(VMCPU_GET_STATE(pVCpu) == VMCPUSTATE_STARTED);
VMCPU_SET_STATE(pVCpu, VMCPUSTATE_STARTED_HALTED);
PUVM pUVM = pUVCpu->pUVM;
int rc = g_aHaltMethods[pUVM->vm.s.iHaltMethod].pfnHalt(pUVCpu, fMask, u64Now);
VMCPU_SET_STATE(pVCpu, VMCPUSTATE_STARTED);
/*
* Notify TM and resume the yielder
*/
TMNotifyEndOfHalt(pVCpu);
if (pVCpu->idCpu == 0)
VMMR3YieldResume(pVM);
LogFlow(("VMR3WaitHalted: returns %Rrc (FF %#x)\n", rc, pVM->fGlobalForcedActions));
return rc;
}
/**
* Suspended VM Wait.
* Only a handful of forced actions will cause the function to
* return to the caller.
*
* @returns VINF_SUCCESS unless a fatal error occurred. In the latter
* case an appropriate status code is returned.
* @param pUVCpu Pointer to the user mode VMCPU structure.
* @thread The emulation thread.
*/
VMMR3DECL(int) VMR3WaitU(PUVMCPU pUVCpu)
{
LogFlow(("VMR3WaitU:\n"));
/*
* Check Relevant FFs.
*/
PVM pVM = pUVCpu->pVM;
PVMCPU pVCpu = pUVCpu->pVCpu;
if ( pVM
&& ( VM_FF_ISPENDING(pVM, VM_FF_EXTERNAL_SUSPENDED_MASK)
|| VMCPU_FF_ISPENDING(pVCpu, VMCPU_FF_EXTERNAL_SUSPENDED_MASK)
)
)
{
LogFlow(("VMR3Wait: returns VINF_SUCCESS (FF %#x)\n", pVM->fGlobalForcedActions));
return VINF_SUCCESS;
}
/*
* Do waiting according to the halt method (so VMR3NotifyFF
* doesn't have to special case anything).
*/
PUVM pUVM = pUVCpu->pUVM;
int rc = g_aHaltMethods[pUVM->vm.s.iHaltMethod].pfnWait(pUVCpu);
LogFlow(("VMR3WaitU: returns %Rrc (FF %#x)\n", rc, pVM ? pVM->fGlobalForcedActions : 0));
return rc;
}
/**
* Rendezvous callback that will be called once.
*
* @returns VBox status code.
* @param pVM VM handle.
* @param pVCpu The VMCPU handle for the calling EMT.
* @param pvUser The new g_aHaltMethods index.
*/
static DECLCALLBACK(int) vmR3SetHaltMethodCallback(PVM pVM, PVMCPU pVCpu, void *pvUser)
{
PUVM pUVM = pVM->pUVM;
uintptr_t i = (uintptr_t)pvUser;
Assert(i < RT_ELEMENTS(g_aHaltMethods));
NOREF(pVCpu);
/*
* Terminate the old one.
*/
if ( pUVM->vm.s.enmHaltMethod != VMHALTMETHOD_INVALID
&& g_aHaltMethods[pUVM->vm.s.iHaltMethod].pfnTerm)
{
g_aHaltMethods[pUVM->vm.s.iHaltMethod].pfnTerm(pUVM);
pUVM->vm.s.enmHaltMethod = VMHALTMETHOD_INVALID;
}
/* Assert that the failure fallback is where we expect. */
Assert(g_aHaltMethods[0].enmHaltMethod == VMHALTMETHOD_BOOTSTRAP);
Assert(!g_aHaltMethods[0].pfnTerm && !g_aHaltMethods[0].pfnInit);
/*
* Init the new one.
*/
int rc = VINF_SUCCESS;
memset(&pUVM->vm.s.Halt, 0, sizeof(pUVM->vm.s.Halt));
if (g_aHaltMethods[i].pfnInit)
{
rc = g_aHaltMethods[i].pfnInit(pUVM);
if (RT_FAILURE(rc))
{
/* Fall back on the bootstrap method. This requires no
init/term (see assertion above), and will always work. */
AssertLogRelRC(rc);
i = 0;
}
}
/*
* Commit it.
*/
pUVM->vm.s.enmHaltMethod = g_aHaltMethods[i].enmHaltMethod;
ASMAtomicWriteU32(&pUVM->vm.s.iHaltMethod, i);
return rc;
}
/**
* Changes the halt method.
*
* @returns VBox status code.
* @param pUVM Pointer to the user mode VM structure.
* @param enmHaltMethod The new halt method.
* @thread EMT.
*/
int vmR3SetHaltMethodU(PUVM pUVM, VMHALTMETHOD enmHaltMethod)
{
PVM pVM = pUVM->pVM; Assert(pVM);
VM_ASSERT_EMT(pVM);
AssertReturn(enmHaltMethod > VMHALTMETHOD_INVALID && enmHaltMethod < VMHALTMETHOD_END, VERR_INVALID_PARAMETER);
/*
* Resolve default (can be overridden in the configuration).
*/
if (enmHaltMethod == VMHALTMETHOD_DEFAULT)
{
uint32_t u32;
int rc = CFGMR3QueryU32(CFGMR3GetChild(CFGMR3GetRoot(pVM), "VM"), "HaltMethod", &u32);
if (RT_SUCCESS(rc))
{
enmHaltMethod = (VMHALTMETHOD)u32;
if (enmHaltMethod <= VMHALTMETHOD_INVALID || enmHaltMethod >= VMHALTMETHOD_END)
return VMSetError(pVM, VERR_INVALID_PARAMETER, RT_SRC_POS, N_("Invalid VM/HaltMethod value %d"), enmHaltMethod);
}
else if (rc == VERR_CFGM_VALUE_NOT_FOUND || rc == VERR_CFGM_CHILD_NOT_FOUND)
return VMSetError(pVM, rc, RT_SRC_POS, N_("Failed to Query VM/HaltMethod as uint32_t"));
else
enmHaltMethod = VMHALTMETHOD_GLOBAL_1;
//enmHaltMethod = VMHALTMETHOD_1;
//enmHaltMethod = VMHALTMETHOD_OLD;
}
LogRel(("VM: Halt method %s (%d)\n", vmR3GetHaltMethodName(enmHaltMethod), enmHaltMethod));
/*
* Find the descriptor.
*/
unsigned i = 0;
while ( i < RT_ELEMENTS(g_aHaltMethods)
&& g_aHaltMethods[i].enmHaltMethod != enmHaltMethod)
i++;
AssertReturn(i < RT_ELEMENTS(g_aHaltMethods), VERR_INVALID_PARAMETER);
/*
* This needs to be done while the other EMTs are not sleeping or otherwise messing around.
*/
return VMMR3EmtRendezvous(pVM, VMMEMTRENDEZVOUS_FLAGS_TYPE_ONCE, vmR3SetHaltMethodCallback, (void *)(uintptr_t)i);
}