#include <lsq.hh>

Inheritance diagram for gem5::o3::LSQ::SplitDataRequest:

Public Member Functions
	SplitDataRequest (LSQUnit port, const DynInstPtr &inst, bool isLoad, const Addr &addr, const uint32_t &size, const Request::Flags &flags_, PacketDataPtr data=nullptr, uint64_t res=nullptr)

virtual	~SplitDataRequest ()

virtual void	markAsStaleTranslation ()

virtual void	finish (const Fault &fault, const RequestPtr &req, gem5::ThreadContext *tc, BaseMMU::Mode mode)

virtual bool	recvTimingResp (PacketPtr pkt)

virtual void	initiateTranslation ()

virtual void	sendPacketToCache ()

virtual void	buildPackets ()

virtual Cycles	handleLocalAccess (gem5::ThreadContext *thread, PacketPtr pkt)
	Memory mapped IPR accesses.

virtual bool	isCacheBlockHit (Addr blockAddr, Addr cacheBlockMask)
	Caches may probe into the load-store queue to enforce memory ordering guarantees.

virtual RequestPtr	mainReq ()

virtual PacketPtr	mainPacket ()

virtual std::string	name () const

Public Member Functions inherited from gem5::o3::LSQ::LSQRequest
void	packetSent ()
	Update the status to reflect that a packet was sent.

void	packetNotSent ()
	Update the status to reflect that a packet was not sent.

void	sendFragmentToTranslation (int i)

bool	isComplete ()

bool	isInTranslation ()

bool	isTranslationComplete ()

bool	isTranslationBlocked ()

bool	isSent ()

bool	isPartialFault ()

bool	isMemAccessRequired ()

void	setStateToFault ()

void	freeLSQEntry ()
	The LSQ entry is cleared.

void	discard ()
	The request is discarded (e.g.

void	packetReplied ()

void	writebackScheduled ()

void	writebackDone ()

void	squashTranslation ()

void	complete ()

void	setContext (const ContextID &context_id)
	Convenience getters/setters.

const DynInstPtr &	instruction ()

bool	hasStaleTranslation () const

void	setVirt (Addr vaddr, unsigned size, Request::Flags flags_, RequestorID requestor_id, Addr pc)
	Set up virtual request.

ContextID	contextId () const

void	taskId (const uint32_t &v)

uint32_t	taskId () const

RequestPtr	req (int idx=0)

const RequestPtr	req (int idx=0) const

Addr	getVaddr (int idx=0) const

PacketPtr	packet (int idx=0)

bool	isAnyOutstandingRequest ()
	Test if there is any in-flight translation or mem access request.

bool	isReleased ()
	Test if the LSQRequest has been released, i.e.

bool	isSplit () const

bool	needWBToRegister () const

Public Member Functions inherited from gem5::BaseMMU::Translation
virtual	~Translation ()

Public Member Functions inherited from gem5::Packet::SenderState
	SenderState ()

virtual	~SenderState ()

Protected Attributes
uint32_t	numFragments

uint32_t	numReceivedPackets

RequestPtr	_mainReq

PacketPtr	_mainPacket

Protected Attributes inherited from gem5::o3::LSQ::LSQRequest
FlagsType	flags

State	_state

uint32_t	numTranslatedFragments

uint32_t	numInTranslationFragments

Additional Inherited Members
Public Attributes inherited from gem5::o3::LSQ::LSQRequest
LSQUnit &	_port

const DynInstPtr	_inst

uint32_t	_taskId

PacketDataPtr	_data

std::vector< PacketPtr >	_packets

std::vector< RequestPtr >	_reqs

std::vector< Fault >	_fault

uint64_t *	_res

const Addr	_addr

const uint32_t	_size

const Request::Flags	_flags

std::vector< bool >	_byteEnable

uint32_t	_numOutstandingPackets

AtomicOpFunctorPtr	_amo_op

bool	_hasStaleTranslation

Public Attributes inherited from gem5::Packet::SenderState
SenderState *	predecessor

Protected Types inherited from gem5::o3::LSQ::LSQRequest
enum	Flag : FlagsStorage { IsLoad = 0x00000001 , WriteBackToRegister = 0x00000002 , Delayed = 0x00000004 , IsSplit = 0x00000008 , TranslationStarted = 0x00000010 , TranslationFinished = 0x00000020 , Sent = 0x00000040 , Retry = 0x00000080 , Complete = 0x00000100 , TranslationSquashed = 0x00000200 , Discarded = 0x00000400 , LSQEntryFreed = 0x00000800 , WritebackScheduled = 0x00001000 , WritebackDone = 0x00002000 , IsAtomic = 0x00004000 }

enum class	State { NotIssued , Translation , Request , Fault , PartialFault }

typedef uint32_t	FlagsStorage

typedef Flags< FlagsStorage >	FlagsType

Protected Member Functions inherited from gem5::o3::LSQ::LSQRequest
void	setState (const State &newState)

void	markDelayed () override
	Signal that the translation has been delayed due to a hw page table walk.

bool	isDelayed ()

LSQUnit *	lsqUnit ()

	LSQRequest (LSQUnit *port, const DynInstPtr &inst, bool isLoad)

	LSQRequest (LSQUnit port, const DynInstPtr &inst, bool isLoad, const Addr &addr, const uint32_t &size, const Request::Flags &flags_, PacketDataPtr data=nullptr, uint64_t res=nullptr, AtomicOpFunctorPtr amo_op=nullptr, bool stale_translation=false)

bool	isLoad () const

bool	isAtomic () const

void	install ()
	Install the request in the LQ/SQ.

bool	squashed () const override
	This function is used by the page table walker to determine if it should translate the a pending request or if the underlying request has been squashed.

void	release (Flag reason)
	Release the LSQRequest.

void	addReq (Addr addr, unsigned size, const std::vector< bool > &byte_enable)
	Helper function used to add a (sub)request, given its address `addr`, size `size` and byte-enable mask `byteEnable`.

virtual	~LSQRequest ()
	Destructor.

Detailed Description

Definition at line 644 of file lsq.hh.

Constructor & Destructor Documentation

◆ SplitDataRequest()

gem5::o3::LSQ::SplitDataRequest::SplitDataRequest	(	LSQUnit *	port,
		const DynInstPtr &	inst,
		bool	isLoad,
		const Addr &	addr,
		const uint32_t &	size,
		const Request::Flags &	flags_,
		PacketDataPtr	data = nullptr,
		uint64_t *	res = nullptr )

inline

Definition at line 653 of file lsq.hh.

References _mainPacket, _mainReq, gem5::X86ISA::addr, data, gem5::o3::LSQ::LSQRequest::flags, gem5::o3::LSQ::LSQRequest::isLoad(), gem5::o3::LSQ::LSQRequest::IsSplit, gem5::o3::LSQ::LSQRequest::LSQRequest(), numFragments, and numReceivedPackets.

◆ ~SplitDataRequest()

virtual gem5::o3::LSQ::SplitDataRequest::~SplitDataRequest ( )

inlinevirtual

Definition at line 666 of file lsq.hh.

References _mainPacket, and _mainReq.

Member Function Documentation

◆ buildPackets()

void gem5::o3::LSQ::SplitDataRequest::buildPackets ( )

virtual

◆ finish()

void gem5::o3::LSQ::SplitDataRequest::finish	(	const Fault &	fault,
		const RequestPtr &	req,
		gem5::ThreadContext *	tc,
		BaseMMU::Mode	mode )

virtual

◆ handleLocalAccess()

Cycles gem5::o3::LSQ::SplitDataRequest::handleLocalAccess	(	gem5::ThreadContext *	thread,
		PacketPtr	pkt )

virtual

Memory mapped IPR accesses.

Implements gem5::o3::LSQ::LSQRequest.

Definition at line 1322 of file lsq.cc.

References gem5::o3::LSQ::LSQRequest::_reqs, gem5::ArmISA::d, gem5::Packet::dataStatic(), gem5::Packet::getPtr(), gem5::o3::LSQ::LSQRequest::isLoad(), gem5::ArmISA::offset, gem5::MipsISA::r, gem5::MemCmd::ReadReq, gem5::o3::LSQ::thread, and gem5::MemCmd::WriteReq.

◆ initiateTranslation()

void gem5::o3::LSQ::SplitDataRequest::initiateTranslation ( )

virtual

Implements gem5::o3::LSQ::LSQRequest.

Definition at line 957 of file lsq.cc.

◆ isCacheBlockHit()

bool gem5::o3::LSQ::SplitDataRequest::isCacheBlockHit	(	Addr	blockAddr,
		Addr	blockMask )

virtual

Caches may probe into the load-store queue to enforce memory ordering guarantees.

This method supports probes by providing a mechanism to compare snoop messages with requests tracked by the load-store queue.

Consistency models must enforce ordering constraints. TSO, for instance, must prevent memory reorderings except stores which are reordered after loads. The reordering restrictions negatively impact performance by cutting down on memory level parallelism. However, the core can regain performance by generating speculative loads. Speculative loads may issue without affecting correctness if precautions are taken to handle invalid memory orders. The load queue must squash under memory model violations. Memory model violations may occur when block ownership is granted to another core or the block cannot be accurately monitored by the load queue.

The load-store queue handles partial faults which complicates this method. Physical addresses must be compared between requests and snoops. Some requests will not have a valid physical address, since partial faults may have outstanding translations. Therefore, the existence of a valid request address must be checked before comparing block hits. We assume no pipeline squash is needed if a valid request address does not exist.

Implements gem5::o3::LSQ::LSQRequest.

Definition at line 1363 of file lsq.cc.

References gem5::o3::LSQ::LSQRequest::_reqs, and gem5::MipsISA::r.