gem5::MemDelay Class Reference

This abstract component provides a mechanism to delay packets. More...

#include <mem_delay.hh>

Inheritance diagram for gem5::MemDelay:

Classes
class	RequestPort
class	ResponsePort

Public Member Functions
	MemDelay (const MemDelayParams &params)
void	init () override
	init() is called after all C++ SimObjects have been created and all ports are connected.
Public Member Functions inherited from gem5::ClockedObject
	ClockedObject (const ClockedObjectParams &p)
void	serialize (CheckpointOut &cp) const override
	Serialize an object.
void	unserialize (CheckpointIn &cp) override
	Unserialize an object.
Public Member Functions inherited from gem5::SimObject
const Params &	params () const
	SimObject (const Params &p)
virtual	~SimObject ()
virtual void	loadState (CheckpointIn &cp)
	loadState() is called on each SimObject when restoring from a checkpoint.
virtual void	initState ()
	initState() is called on each SimObject when not restoring from a checkpoint.
virtual void	regProbePoints ()
	Register probe points for this object.
virtual void	regProbeListeners ()
	Register probe listeners for this object.
ProbeManager *	getProbeManager ()
	Get the probe manager for this object.
virtual void	startup ()
	startup() is the final initialization call before simulation.
DrainState	drain () override
	Provide a default implementation of the drain interface for objects that don't need draining.
virtual void	memWriteback ()
	Write back dirty buffers to memory using functional writes.
virtual void	memInvalidate ()
	Invalidate the contents of memory buffers.
void	serialize (CheckpointOut &cp) const override
	Serialize an object.
void	unserialize (CheckpointIn &cp) override
	Unserialize an object.
Public Member Functions inherited from gem5::EventManager
EventQueue *	eventQueue () const
void	schedule (Event &event, Tick when)
void	deschedule (Event &event)
void	reschedule (Event &event, Tick when, bool always=false)
void	schedule (Event *event, Tick when)
void	deschedule (Event *event)
void	reschedule (Event *event, Tick when, bool always=false)
void	wakeupEventQueue (Tick when=(Tick) -1)
	This function is not needed by the usual gem5 event loop but may be necessary in derived EventQueues which host gem5 on other schedulers.
void	setCurTick (Tick newVal)
	EventManager (EventManager &em)
	Event manger manages events in the event queue.
	EventManager (EventManager *em)
	EventManager (EventQueue *eq)
Public Member Functions inherited from gem5::Serializable
	Serializable ()
virtual	~Serializable ()
void	serializeSection (CheckpointOut &cp, const char *name) const
	Serialize an object into a new section.
void	serializeSection (CheckpointOut &cp, const std::string &name) const
void	unserializeSection (CheckpointIn &cp, const char *name)
	Unserialize an a child object.
void	unserializeSection (CheckpointIn &cp, const std::string &name)
Public Member Functions inherited from gem5::Drainable
DrainState	drainState () const
	Return the current drain state of an object.
virtual void	notifyFork ()
	Notify a child process of a fork.
Public Member Functions inherited from gem5::statistics::Group
	Group (Group *parent, const char *name=nullptr)
	Construct a new statistics group.
virtual	~Group ()
virtual void	regStats ()
	Callback to set stat parameters.
virtual void	resetStats ()
	Callback to reset stats.
virtual void	preDumpStats ()
	Callback before stats are dumped.
void	addStat (statistics::Info *info)
	Register a stat with this group.
const std::map< std::string, Group * > &	getStatGroups () const
	Get all child groups associated with this object.
const std::vector< Info * > &	getStats () const
	Get all stats associated with this object.
void	addStatGroup (const char *name, Group *block)
	Add a stat block as a child of this block.
const Info *	resolveStat (std::string name) const
	Resolve a stat by its name within this group.
void	mergeStatGroup (Group *block)
	Merge the contents (stats & children) of a block to this block.
	Group ()=delete
	Group (const Group &)=delete
Group &	operator= (const Group &)=delete
Public Member Functions inherited from gem5::Named
	Named (const std::string &name_)
virtual	~Named ()=default
virtual std::string	name () const
Public Member Functions inherited from gem5::Clocked
void	updateClockPeriod ()
	Update the tick to the current tick.
Tick	clockEdge (Cycles cycles=Cycles(0)) const
	Determine the tick when a cycle begins, by default the current one, but the argument also enables the caller to determine a future cycle.
Cycles	curCycle () const
	Determine the current cycle, corresponding to a tick aligned to a clock edge.
Tick	nextCycle () const
	Based on the clock of the object, determine the start tick of the first cycle that is at least one cycle in the future.
uint64_t	frequency () const
Tick	clockPeriod () const
double	voltage () const
Cycles	ticksToCycles (Tick t) const
Tick	cyclesToTicks (Cycles c) const

Protected Member Functions
Port &	getPort (const std::string &if_name, PortID idx=InvalidPortID) override
	Get a port with a given name and index.
bool	trySatisfyFunctional (PacketPtr pkt)
virtual Tick	delayReq (PacketPtr pkt)
	Delay a request by some number of ticks.
virtual Tick	delayResp (PacketPtr pkt)
	Delay a response by some number of ticks.
virtual Tick	delaySnoopResp (PacketPtr pkt)
	Delay a snoop response by some number of ticks.
Protected Member Functions inherited from gem5::Drainable
	Drainable ()
virtual	~Drainable ()
virtual void	drainResume ()
	Resume execution after a successful drain.
void	signalDrainDone () const
	Signal that an object is drained.
Protected Member Functions inherited from gem5::Clocked
	Clocked (ClockDomain &clk_domain)
	Create a clocked object and set the clock domain based on the parameters.
	Clocked (Clocked &)=delete
Clocked &	operator= (Clocked &)=delete
virtual	~Clocked ()
	Virtual destructor due to inheritance.
void	resetClock () const
	Reset the object's clock using the current global tick value.
virtual void	clockPeriodUpdated ()
	A hook subclasses can implement so they can do any extra work that's needed when the clock rate is changed.

Protected Attributes
RequestPort	requestPort
ResponsePort	responsePort
ReqPacketQueue	reqQueue
RespPacketQueue	respQueue
SnoopRespPacketQueue	snoopRespQueue
Protected Attributes inherited from gem5::SimObject
const SimObjectParams &	_params
	Cached copy of the object parameters.
Protected Attributes inherited from gem5::EventManager
EventQueue *	eventq
	A pointer to this object's event queue.

Additional Inherited Members
Public Types inherited from gem5::ClockedObject
using	Params = ClockedObjectParams
	Parameters of ClockedObject.
Public Types inherited from gem5::SimObject
typedef SimObjectParams	Params
Static Public Member Functions inherited from gem5::SimObject
static void	serializeAll (const std::string &cpt_dir)
	Create a checkpoint by serializing all SimObjects in the system.
static SimObject *	find (const char *name)
	Find the SimObject with the given name and return a pointer to it.
static void	setSimObjectResolver (SimObjectResolver *resolver)
	There is a single object name resolver, and it is only set when simulation is restoring from checkpoints.
static SimObjectResolver *	getSimObjectResolver ()
	There is a single object name resolver, and it is only set when simulation is restoring from checkpoints.
Static Public Member Functions inherited from gem5::Serializable
static const std::string &	currentSection ()
	Gets the fully-qualified name of the active section.
static void	generateCheckpointOut (const std::string &cpt_dir, std::ofstream &outstream)
	Generate a checkpoint file so that the serialization can be routed to it.
Public Attributes inherited from gem5::ClockedObject
PowerState *	powerState

Detailed Description

This abstract component provides a mechanism to delay packets.

It can be spliced between arbitrary ports of the memory system and delays packets that pass through it.

Specialisations of this abstract class should override at least one of delayReq, delayResp, deleySnoopReq, delaySnoopResp. These methods receive a PacketPtr as their argument and return a delay in Ticks. The base class implements an infinite buffer to hold delayed packets until they are ready. The intention is to use this component for rapid prototyping of other memory system components that introduce a packet processing delays.

NOTE: Packets may be reordered if the delays aren't constant.

Definition at line 65 of file mem_delay.hh.

Constructor & Destructor Documentation

MemDelay()

gem5::MemDelay::MemDelay

(

const MemDelayParams &

params

)

Definition at line 46 of file mem_delay.cc.

Member Function Documentation

delayReq()

virtual Tick gem5::MemDelay::delayReq ( PacketPtr pkt )

inlineprotectedvirtual

Delay a request by some number of ticks.

Returns

Ticks to delay packet.

Reimplemented in gem5::SimpleMemDelay.

Definition at line 141 of file mem_delay.hh.

delayResp()

virtual Tick gem5::MemDelay::delayResp ( PacketPtr pkt )

inlineprotectedvirtual

Delay a response by some number of ticks.

Returns

Ticks to delay packet.

Reimplemented in gem5::SimpleMemDelay.

Definition at line 148 of file mem_delay.hh.

delaySnoopResp()

virtual Tick gem5::MemDelay::delaySnoopResp ( PacketPtr pkt )

inlineprotectedvirtual

Delay a snoop response by some number of ticks.

Returns

Ticks to delay packet.

Definition at line 155 of file mem_delay.hh.

getPort()

Port & gem5::MemDelay::getPort ( const std::string & if_name, PortID idx = InvalidPortID )

overrideprotectedvirtual

Get a port with a given name and index.

This is used at binding time and returns a reference to a protocol-agnostic port.

gem5 has a request and response port interface. All memory objects are connected together via ports. These ports provide a rigid interface between these memory objects. These ports implement three different memory system modes: timing, atomic, and functional. The most important mode is the timing mode and here timing mode is used for conducting cycle-level timing experiments. The other modes are only used in special circumstances and should not be used to conduct cycle-level timing experiments. The other modes are only used in special circumstances. These ports allow SimObjects to communicate with each other.

Parameters

if_name	Port name
idx	Index in the case of a VectorPort

Returns

A reference to the given port

Reimplemented from gem5::SimObject.

Definition at line 65 of file mem_delay.cc.

References gem5::SimObject::getPort(), requestPort, and responsePort.

init()

void gem5::MemDelay::init ( )

overridevirtual

init() is called after all C++ SimObjects have been created and all ports are connected.

Initializations that are independent of unserialization but rely on a fully instantiated and connected SimObject graph should be done here.

Reimplemented from gem5::SimObject.

Definition at line 57 of file mem_delay.cc.

References fatal, gem5::Port::isConnected(), requestPort, and responsePort.

trySatisfyFunctional()

bool gem5::MemDelay::trySatisfyFunctional ( PacketPtr pkt )

protected

Definition at line 77 of file mem_delay.cc.

References requestPort, responsePort, gem5::QueuedRequestPort::trySatisfyFunctional(), and gem5::QueuedResponsePort::trySatisfyFunctional().

Member Data Documentation

reqQueue

ReqPacketQueue gem5::MemDelay::reqQueue

protected

Definition at line 131 of file mem_delay.hh.

requestPort

RequestPort gem5::MemDelay::requestPort

protected

Definition at line 128 of file mem_delay.hh.

Referenced by gem5::MemDelay::ResponsePort::getAddrRanges(), getPort(), init(), and trySatisfyFunctional().

responsePort

ResponsePort gem5::MemDelay::responsePort

protected

Definition at line 129 of file mem_delay.hh.

Referenced by getPort(), init(), gem5::MemDelay::RequestPort::isSnooping(), gem5::MemDelay::RequestPort::recvRangeChange(), and trySatisfyFunctional().

respQueue

RespPacketQueue gem5::MemDelay::respQueue

protected

Definition at line 132 of file mem_delay.hh.

snoopRespQueue

SnoopRespPacketQueue gem5::MemDelay::snoopRespQueue

protected

Definition at line 133 of file mem_delay.hh.

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

• mem/mem_delay.hh
• mem/mem_delay.cc