ARM implementation of a KVM-based hardware virtualized CPU. More...

#include <arm_cpu.hh>

Inheritance diagram for ArmKvmCPU:

Classes
struct	KvmCoreMiscRegInfo

struct	KvmIntRegInfo

Public Member Functions
	ArmKvmCPU (ArmKvmCPUParams *params)

virtual	~ArmKvmCPU ()

void	startup ()

void	dump ()

Public Member Functions inherited from BaseKvmCPU
	BaseKvmCPU (BaseKvmCPUParams *params)

virtual	~BaseKvmCPU ()

void	init () override

void	startup () override

void	regStats () override

void	serializeThread (CheckpointOut &cp, ThreadID tid) const override

void	unserializeThread (CheckpointIn &cp, ThreadID tid) override

DrainState	drain () override

void	drainResume () override

void	notifyFork () override

void	switchOut () override

void	takeOverFrom (BaseCPU *cpu) override

void	verifyMemoryMode () const override

MasterPort &	getDataPort () override

MasterPort &	getInstPort () override

void	wakeup (ThreadID tid=0) override

void	activateContext (ThreadID thread_num) override

void	suspendContext (ThreadID thread_num) override

void	deallocateContext (ThreadID thread_num)

void	haltContext (ThreadID thread_num) override

long	getVCpuID () const

ThreadContext *	getContext (int tn) override

Counter	totalInsts () const override

Counter	totalOps () const override

void	finishMMIOPending ()
	Callback from KvmCPUPort to transition the CPU out of RunningMMIOPending when all timing requests have completed. More...

virtual void	dump () const
	Dump the internal state to the terminal. More...

void	kick () const
	Force an exit from KVM. More...

Protected Types
typedef std::vector< uint64_t >	RegIndexVector

Protected Types inherited from BaseKvmCPU
enum	Status { Idle, Running, RunningService, RunningMMIOPending, RunningServiceCompletion }

Protected Member Functions
Tick	kvmRun (Tick ticks)
	Request KVM to run the guest for a given number of ticks. More...

void	updateKvmState ()
	Update the KVM state from the current thread context. More...

void	updateThreadContext ()
	Update the current thread context with the KVM state. More...

Tick	onKvmExitHypercall ()

const RegIndexVector &	getRegList () const
	Get a list of registers supported by getOneReg() and setOneReg(). More...

void	kvmArmVCpuInit (uint32_t target)

void	kvmArmVCpuInit (const struct kvm_vcpu_init &init)

ArmISA::MiscRegIndex	decodeCoProcReg (uint64_t id) const

ArmISA::MiscRegIndex	decodeVFPCtrlReg (uint64_t id) const

bool	isInvariantReg (uint64_t id)
	Determine if a register is invariant. More...

Protected Member Functions inherited from BaseKvmCPU
void	tick ()
	Execute the CPU until the next event in the main event queue or until the guest needs service from gem5. More...

virtual uint64_t	getHostCycles () const
	Get the value of the hardware cycle counter in the guest. More...

virtual Tick	kvmRunDrain ()
	Request the CPU to run until draining completes. More...

struct kvm_run *	getKvmRunState ()
	Get a pointer to the kvm_run structure containing all the input and output parameters from kvmRun(). More...

uint8_t *	getGuestData (uint64_t offset) const
	Retrieve a pointer to guest data stored at the end of the kvm_run structure. More...

void	kvmNonMaskableInterrupt ()
	Send a non-maskable interrupt to the guest. More...

void	kvmInterrupt (const struct kvm_interrupt &interrupt)
	Send a normal interrupt to the guest. More...

std::string	getAndFormatOneReg (uint64_t id) const
	Get and format one register for printout. More...

virtual bool	archIsDrained () const
	Is the architecture specific code in a state that prevents draining? More...

Tick	doMMIOAccess (Addr paddr, void *data, int size, bool write)
	Inject a memory mapped IO request into gem5. More...

int	ioctl (int request, long p1) const
	vCPU ioctl interface. More...

int	ioctl (int request, void *p1) const

int	ioctl (int request) const

void	getRegisters (struct kvm_regs &regs) const
	Get/Set the register state of the guest vCPU. More...

void	setRegisters (const struct kvm_regs &regs)

void	getSpecialRegisters (struct kvm_sregs &regs) const

void	setSpecialRegisters (const struct kvm_sregs &regs)

void	getFPUState (struct kvm_fpu &state) const
	Get/Set the guest FPU/vector state. More...

void	setFPUState (const struct kvm_fpu &state)

void	setOneReg (uint64_t id, const void *addr)
	Get/Set single register using the KVM_(SET\|GET)_ONE_REG API. More...

void	setOneReg (uint64_t id, uint64_t value)

void	setOneReg (uint64_t id, uint32_t value)

void	getOneReg (uint64_t id, void *addr) const

uint64_t	getOneRegU64 (uint64_t id) const

uint32_t	getOneRegU32 (uint64_t id) const

void	syncThreadContext ()
	Update a thread context if the KVM state is dirty with respect to the cached thread context. More...

void	syncKvmState ()
	Update the KVM if the thread context is dirty. More...

virtual Tick	handleKvmExit ()
	Main kvmRun exit handler, calls the relevant handleKvmExit* depending on exit type. More...

virtual Tick	handleKvmExitIO ()
	The guest performed a legacy IO request (out/inp on x86) More...

virtual Tick	handleKvmExitHypercall ()
	The guest requested a monitor service using a hypercall. More...

virtual Tick	handleKvmExitIRQWindowOpen ()
	The guest exited because an interrupt window was requested. More...

virtual Tick	handleKvmExitUnknown ()
	An unknown architecture dependent error occurred when starting the vCPU. More...

virtual Tick	handleKvmExitException ()
	An unhandled virtualization exception occured. More...

virtual Tick	handleKvmExitFailEntry ()
	KVM failed to start the virtualized CPU. More...

void	setSignalMask (const sigset_t *mask)
	Set the signal mask used in kvmRun() More...

Static Protected Attributes
static KvmIntRegInfo	kvmIntRegs []

static KvmCoreMiscRegInfo	kvmCoreMiscRegs []

Private Member Functions
bool	getRegList (struct kvm_reg_list &regs) const
	Get a list of registers supported by getOneReg() and setOneReg(). More...

void	dumpKvmStateCore ()

void	dumpKvmStateMisc ()

void	dumpKvmStateCoProc (uint64_t id)

void	dumpKvmStateVFP (uint64_t id)

void	updateKvmStateCore ()

void	updateKvmStateMisc ()

void	updateKvmStateCoProc (uint64_t id, bool show_warnings)

void	updateKvmStateVFP (uint64_t id, bool show_warnings)

void	updateTCStateCore ()

void	updateTCStateMisc ()

void	updateTCStateCoProc (uint64_t id, bool show_warnings)

void	updateTCStateVFP (uint64_t id, bool show_warnings)

Private Attributes
bool	irqAsserted
	Cached state of the IRQ line. More...

bool	fiqAsserted
	Cached state of the FIQ line. More...

RegIndexVector	_regIndexList
	Cached copy of the list of co-processor registers supported by KVM. More...

Static Private Attributes
static const std::set< uint64_t >	invariant_regs
	List of co-processor registers that KVM requires to be identical on both the host and the guest. More...

Additional Inherited Members
Static Public Member Functions inherited from BaseCPU
static int	numSimulatedInsts ()

static int	numSimulatedOps ()

static void	wakeup (ThreadID tid)

Public Attributes inherited from BaseKvmCPU
SimpleThread *	thread
	A cached copy of a thread's state in the form of a SimpleThread object. More...

ThreadContext *	tc
	ThreadContext object, provides an interface for external objects to modify this thread's state. More...

KvmVM &	vm

Counter	ctrInsts
	Number of instructions executed by the CPU. More...

Stats::Scalar	numInsts

Stats::Scalar	numVMExits

Stats::Scalar	numVMHalfEntries

Stats::Scalar	numExitSignal

Stats::Scalar	numMMIO

Stats::Scalar	numCoalescedMMIO

Stats::Scalar	numIO

Stats::Scalar	numHalt

Stats::Scalar	numInterrupts

Stats::Scalar	numHypercalls

Protected Attributes inherited from BaseKvmCPU
Status	_status
	CPU run state. More...

KVMCpuPort	dataPort
	Port for data requests. More...

KVMCpuPort	instPort
	Unused dummy port for the instruction interface. More...

const bool	alwaysSyncTC
	Be conservative and always synchronize the thread context on KVM entry/exit. More...

bool	threadContextDirty
	Is the gem5 context dirty? Set to true to force an update of the KVM vCPU state upon the next call to kvmRun(). More...

bool	kvmStateDirty
	Is the KVM state dirty? Set to true to force an update of the KVM vCPU state upon the next call to kvmRun(). More...

const long	vcpuID
	KVM internal ID of the vCPU. More...

pthread_t	vcpuThread
	ID of the vCPU thread. More...

Detailed Description

ARM implementation of a KVM-based hardware virtualized CPU.

Architecture specific limitations:

LPAE is currently not supported by gem5. We therefore panic if LPAE is enabled when returning to gem5.
The co-processor based interface to the architected timer is unsupported. We can't support this due to limitations in the KVM API on ARM.
M5 ops are currently not supported. This requires either a kernel hack or a memory mapped device that handles the guest<->m5 interface.

Definition at line 61 of file arm_cpu.hh.

Member Typedef Documentation

typedef std::vector<uint64_t> ArmKvmCPU::RegIndexVector

protected

Definition at line 90 of file arm_cpu.hh.

Constructor & Destructor Documentation

ArmKvmCPU::ArmKvmCPU ( ArmKvmCPUParams * params )

Definition at line 245 of file arm_cpu.cc.

ArmKvmCPU::~ArmKvmCPU ( )

virtual

Definition at line 251 of file arm_cpu.cc.

Member Function Documentation

MiscRegIndex ArmKvmCPU::decodeCoProcReg ( uint64_t id ) const

protected

Definition at line 376 of file arm_cpu.cc.

References ArmISA::decodeCP14Reg(), ArmISA::decodeCP15Reg(), AlphaISA::NUM_MISCREGS, ArmISA::opc2, REG_CP, REG_CRM, REG_CRN, REG_IS_32BIT, REG_IS_64BIT, REG_OPC1, REG_OPC2, and warn.

Referenced by dumpKvmStateCoProc(), updateKvmStateCoProc(), and updateTCStateCoProc().

ArmISA::MiscRegIndex ArmKvmCPU::decodeVFPCtrlReg ( uint64_t id ) const

protected

Definition at line 411 of file arm_cpu.cc.

References ArmISA::MISCREG_FPEXC, ArmISA::MISCREG_FPSCR, ArmISA::MISCREG_FPSID, ArmISA::MISCREG_MVFR0, ArmISA::MISCREG_MVFR1, AlphaISA::NUM_MISCREGS, REG_IS_ARM, REG_IS_VFP, REG_IS_VFP_CTRL, REG_VFP_REG, and warn_once.

Referenced by dumpKvmStateVFP(), updateKvmStateVFP(), and updateTCStateVFP().

void ArmKvmCPU::dump ( )

Definition at line 291 of file arm_cpu.cc.

References dumpKvmStateCore(), and dumpKvmStateMisc().

void ArmKvmCPU::dumpKvmStateCoProc ( uint64_t id )

private

Definition at line 523 of file arm_cpu.cc.

References decodeCoProcReg(), EXTRACT_FIELD, BaseKvmCPU::getAndFormatOneReg(), BaseKvmCPU::getOneRegU32(), inform, isInvariantReg(), ArmISA::miscRegName, name(), AlphaISA::NUM_MISCREGS, ThreadContext::readMiscReg(), ThreadContext::readMiscRegNoEffect(), REG_CP, REG_CRM, REG_CRN, REG_IS_32BIT, REG_IS_ARM, REG_OPC1, REG_OPC2, and BaseKvmCPU::tc.

Referenced by dumpKvmStateMisc().

void ArmKvmCPU::dumpKvmStateCore ( )

private

Definition at line 462 of file arm_cpu.cc.

References BaseKvmCPU::getOneRegU32(), ArmKvmCPU::KvmIntRegInfo::idx, ArmKvmCPU::KvmCoreMiscRegInfo::idx, inform, kvmCoreMiscRegs, kvmIntRegs, ArmISA::miscRegName, ArmISA::NUM_INTREGS, AlphaISA::NUM_MISCREGS, pc, and REG_CORE32.

Referenced by dump(), updateKvmStateCore(), and updateTCStateCore().

void ArmKvmCPU::dumpKvmStateMisc ( )

private

Definition at line 484 of file arm_cpu.cc.

References dumpKvmStateCoProc(), dumpKvmStateVFP(), EXTRACT_FIELD, BaseKvmCPU::getAndFormatOneReg(), getRegList(), SparcISA::id, inform, REG_CP, REG_IS_ARM, REG_IS_CORE, REG_IS_DEMUX, and REG_IS_VFP.

Referenced by dump(), updateKvmStateMisc(), and updateTCStateMisc().

void ArmKvmCPU::dumpKvmStateVFP ( uint64_t id )

private

Definition at line 565 of file arm_cpu.cc.

References decodeVFPCtrlReg(), BaseKvmCPU::getAndFormatOneReg(), inform, ArmISA::miscRegName, AlphaISA::NUM_MISCREGS, REG_IS_ARM, REG_IS_VFP, REG_IS_VFP_CTRL, and REG_IS_VFP_REG.

Referenced by dumpKvmStateMisc().

const ArmKvmCPU::RegIndexVector & ArmKvmCPU::getRegList ( ) const

protected

Get a list of registers supported by getOneReg() and setOneReg().

Definition at line 336 of file arm_cpu.cc.

References _regIndexList, and ArmISA::i.

Referenced by dumpKvmStateMisc(), updateKvmStateMisc(), and updateTCStateMisc().

bool ArmKvmCPU::getRegList ( struct kvm_reg_list & regs ) const

private

Get a list of registers supported by getOneReg() and setOneReg().

Returns: False if the number of elements allocated in the list is too small to hold the complete register list (the required value is written into n in this case). True on success.

Definition at line 447 of file arm_cpu.cc.

References BaseKvmCPU::ioctl(), and panic.

bool ArmKvmCPU::isInvariantReg ( uint64_t id )

protected

Determine if a register is invariant.

Some registers must have the same value in both the host and the guest. Such registers are referred to as "invariant" registers in KVM. This is a restriction imposed by KVM as having different values in ID registers (e.g., the cache identification registers) would confuse the guest kernel.

Definition at line 435 of file arm_cpu.cc.

References invariant_regs, REG_IS_ARM, and REG_IS_DEMUX.

Referenced by dumpKvmStateCoProc(), and updateKvmStateMisc().

void ArmKvmCPU::kvmArmVCpuInit ( uint32_t target )

protected

Definition at line 357 of file arm_cpu.cc.

Referenced by startup().

void ArmKvmCPU::kvmArmVCpuInit ( const struct kvm_vcpu_init & init )

protected

Definition at line 369 of file arm_cpu.cc.

References BaseKvmCPU::ioctl(), and panic.

Tick ArmKvmCPU::kvmRun ( Tick ticks )

protectedvirtual

Request KVM to run the guest for a given number of ticks.

The method returns the approximate number of ticks executed.

Note: The returned number of ticks can be both larger or smaller than the requested number of ticks. A smaller number can, for example, occur when the guest executes MMIO. A larger number is typically due to performance counter inaccuracies.; This method is virtual in order to allow implementations to check for architecture specific events (e.g., interrupts) before entering the VM.; It is the response of the caller (normally tick()) to make sure that the KVM state is synchronized and that the TC is invalidated after entering KVM.; This method does not normally cause any state transitions. However, if it may suspend the CPU by suspending the thread, which leads to a transition to the Idle state. In such a case, kvm must not be entered.

Parameters

ticks Number of ticks to execute, set to 0 to exit immediately after finishing pending operations.

Returns: Number of ticks executed (see note)

Reimplemented from BaseKvmCPU.

Definition at line 271 of file arm_cpu.cc.

References DPRINTF, fiqAsserted, ArmISA::INT_FIQ, ArmISA::INT_IRQ, INTERRUPT_VCPU_FIQ, INTERRUPT_VCPU_IRQ, irqAsserted, BaseKvmCPU::kvmRun(), KvmVM::setIRQLine(), BaseKvmCPU::vcpuID, and BaseKvmCPU::vm.

Tick ArmKvmCPU::onKvmExitHypercall ( )

protected

Definition at line 316 of file arm_cpu.cc.

References DPRINTF, BaseKvmCPU::getContext(), ArmISA::INTREG_R12, PseudoInst::pseudoInst(), ThreadContext::readIntRegFlat(), REG_CORE32, BaseKvmCPU::setOneReg(), and BaseKvmCPU::tc.

void ArmKvmCPU::startup ( )

Definition at line 256 of file arm_cpu.cc.

References kvmArmVCpuInit(), and BaseKvmCPU::startup().

void ArmKvmCPU::updateKvmState ( )

protectedvirtual

Update the KVM state from the current thread context.

The base CPU calls this method before starting the guest CPU when the contextDirty flag is set. The architecture dependent CPU implementation is expected to update all guest state (registers, special registers, and FPU state).

Implements BaseKvmCPU.

Definition at line 298 of file arm_cpu.cc.

References DPRINTF, updateKvmStateCore(), and updateKvmStateMisc().

void ArmKvmCPU::updateKvmStateCoProc	(	uint64_t	id,
		bool	show_warnings
	)

private

Definition at line 650 of file arm_cpu.cc.

References decodeCoProcReg(), hack, KVM_REG64_TTBR0(), KVM_REG64_TTBR1(), ArmISA::MISCREG_TTBR0, ArmISA::MISCREG_TTBR1, ArmISA::miscRegName, AlphaISA::NUM_MISCREGS, ThreadContext::readMiscRegNoEffect(), X86ISA::reg, REG_CP, REG_CRM, REG_CRN, REG_IS_64BIT, REG_IS_ARM, REG_OPC1, REG_OPC2, BaseKvmCPU::setOneReg(), BaseKvmCPU::tc, and warn.

Referenced by updateKvmStateMisc().

void ArmKvmCPU::updateKvmStateCore ( )

private

Definition at line 586 of file arm_cpu.cc.

References DPRINTF, DTRACE, dumpKvmStateCore(), ArmKvmCPU::KvmIntRegInfo::idx, ArmKvmCPU::KvmCoreMiscRegInfo::idx, ThreadContext::instAddr(), kvmCoreMiscRegs, kvmIntRegs, ArmISA::NUM_INTREGS, AlphaISA::NUM_MISCREGS, ThreadContext::readIntRegFlat(), ThreadContext::readMiscReg(), REG_CORE32, BaseKvmCPU::setOneReg(), and BaseKvmCPU::tc.

Referenced by updateKvmState().

void ArmKvmCPU::updateKvmStateMisc ( )

private

Definition at line 612 of file arm_cpu.cc.

References DPRINTF, DTRACE, dumpKvmStateMisc(), getRegList(), isInvariantReg(), REG_CP, REG_IS_ARM, REG_IS_CORE, REG_IS_VFP, updateKvmStateCoProc(), updateKvmStateVFP(), and warn.

Referenced by updateKvmState().

void ArmKvmCPU::updateKvmStateVFP	(	uint64_t	id,
		bool	show_warnings
	)

private

Definition at line 684 of file arm_cpu.cc.

References decodeVFPCtrlReg(), ArmISA::miscRegName, AlphaISA::NUM_MISCREGS, ThreadContext::readFloatRegBitsFlat(), ThreadContext::readMiscReg(), REG_IS_32BIT, REG_IS_64BIT, REG_IS_ARM, REG_IS_VFP, REG_IS_VFP_CTRL, REG_IS_VFP_REG, BaseKvmCPU::setOneReg(), BaseKvmCPU::tc, and warn.

Referenced by updateKvmStateMisc().

void ArmKvmCPU::updateTCStateCoProc	(	uint64_t	id,
		bool	show_warnings
	)

private

Definition at line 789 of file arm_cpu.cc.

References decodeCoProcReg(), BaseKvmCPU::getOneRegU32(), BaseKvmCPU::getOneRegU64(), hack_once, KVM_REG64_TTBR0(), KVM_REG64_TTBR1(), ArmISA::MISCREG_TTBCR, ArmISA::MISCREG_TTBR0, ArmISA::MISCREG_TTBR1, ArmISA::miscRegName, AlphaISA::NUM_MISCREGS, panic, X86ISA::reg, REG_CP, REG_CRM, REG_CRN, REG_IS_64BIT, REG_IS_ARM, REG_OPC1, REG_OPC2, ThreadContext::setMiscRegNoEffect(), BaseKvmCPU::tc, warn, and warn_once.

Referenced by updateTCStateMisc().

void ArmKvmCPU::updateTCStateCore ( )

private

void ArmKvmCPU::updateTCStateMisc ( )

private

Definition at line 756 of file arm_cpu.cc.

References DTRACE, dumpKvmStateMisc(), getRegList(), REG_CP, REG_IS_ARM, REG_IS_CORE, REG_IS_VFP, updateTCStateCoProc(), updateTCStateVFP(), and warn.

Referenced by updateThreadContext().

void ArmKvmCPU::updateTCStateVFP	(	uint64_t	id,
		bool	show_warnings
	)

private

Definition at line 825 of file arm_cpu.cc.

References decodeVFPCtrlReg(), BaseKvmCPU::getOneRegU64(), ArmISA::miscRegName, AlphaISA::NUM_MISCREGS, REG_IS_32BIT, REG_IS_64BIT, REG_IS_ARM, REG_IS_VFP, REG_IS_VFP_CTRL, REG_IS_VFP_REG, ThreadContext::setFloatRegBitsFlat(), ThreadContext::setMiscReg(), BaseKvmCPU::tc, and warn.

Referenced by updateTCStateMisc().

void ArmKvmCPU::updateThreadContext ( )

protectedvirtual

Update the current thread context with the KVM state.

The base CPU after the guest updates any of the KVM state. In practice, this happens after kvmRun is called. The architecture dependent code is expected to read the state of the guest CPU and update gem5's thread state.

Implements BaseKvmCPU.

Definition at line 307 of file arm_cpu.cc.

References DPRINTF, updateTCStateCore(), and updateTCStateMisc().

Member Data Documentation

RegIndexVector ArmKvmCPU::_regIndexList

mutableprivate

Cached copy of the list of co-processor registers supported by KVM.

Definition at line 160 of file arm_cpu.hh.

Referenced by getRegList().

bool ArmKvmCPU::fiqAsserted

private

Cached state of the FIQ line.

Definition at line 154 of file arm_cpu.hh.

Referenced by kvmRun().

const std::set< uint64_t > ArmKvmCPU::invariant_regs

staticprivate

List of co-processor registers that KVM requires to be identical on both the host and the guest.

KVM does not allow writes to these registers.

Definition at line 167 of file arm_cpu.hh.

Referenced by isInvariantReg().

bool ArmKvmCPU::irqAsserted

private

Cached state of the IRQ line.

Definition at line 152 of file arm_cpu.hh.

Referenced by kvmRun().

ArmKvmCPU::KvmCoreMiscRegInfo ArmKvmCPU::kvmCoreMiscRegs

staticprotected

Initial value:

= {
    { REG_CORE32(usr_regs.ARM_cpsr), MISCREG_CPSR, "CPSR" },
    { REG_CORE32(svc_regs[2]), MISCREG_SPSR_SVC, "SPSR(SVC)" },
    { REG_CORE32(abt_regs[2]), MISCREG_SPSR_ABT, "SPSR(ABT)" },
    { REG_CORE32(und_regs[2]), MISCREG_SPSR_UND, "SPSR(UND)" },
    { REG_CORE32(irq_regs[2]), MISCREG_SPSR_IRQ, "SPSR(IRQ)" },
    { REG_CORE32(fiq_regs[2]), MISCREG_SPSR_FIQ, "SPSR(FIQ)" },
    { 0, NUM_MISCREGS }
}

Definition at line 123 of file arm_cpu.hh.

Referenced by dumpKvmStateCore(), updateKvmStateCore(), and updateTCStateCore().

ArmKvmCPU::KvmIntRegInfo ArmKvmCPU::kvmIntRegs

staticprotected

Definition at line 122 of file arm_cpu.hh.

Referenced by dumpKvmStateCore(), updateKvmStateCore(), and updateTCStateCore().

The documentation for this class was generated from the following files:

arch/arm/kvm/arm_cpu.hh
arch/arm/kvm/arm_cpu.cc

Classes

Public Member Functions

Protected Types

Protected Member Functions

Static Protected Attributes

Private Member Functions

Private Attributes

Static Private Attributes

Additional Inherited Members

Detailed Description

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation