Pool of FU's, specific to the new CPU model. More...

#include <fu_pool.hh>

Inheritance diagram for FUPool:

Classes
class	FUIdxQueue
	Class that implements a circular queue to hold FU indices. More...

Public Types
typedef FUPoolParams	Params

Public Types inherited from SimObject
typedef SimObjectParams	Params

Public Member Functions
	FUPool (const Params *p)
	Constructs a FU pool. More...

	~FUPool ()

int	getUnit (OpClass capability)
	Gets a FU providing the requested capability. More...

void	freeUnitNextCycle (int fu_idx)
	Frees a FU at the end of this cycle. More...

void	processFreeUnits ()
	Frees all FUs on the list. More...

int	size ()
	Returns the total number of FUs. More...

void	dump ()
	Debugging function used to dump FU information. More...

Cycles	getOpLatency (OpClass capability)
	Returns the operation execution latency of the given capability. More...

bool	isPipelined (OpClass capability)
	Returns the issue latency of the given capability. More...

bool	isDrained () const
	Have all the FUs drained? More...

void	takeOverFrom ()
	Takes over from another CPU's thread. More...

Public Member Functions inherited from SimObject
const Params *	params () const

	SimObject (const Params *_params)

virtual	~SimObject ()

virtual const std::string	name () const

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

virtual void	loadState (CheckpointIn &cp)
	loadState() is called on each SimObject when restoring from a checkpoint. More...

virtual void	initState ()
	initState() is called on each SimObject when not restoring from a checkpoint. More...

virtual void	regProbePoints ()
	Register probe points for this object. More...

virtual void	regProbeListeners ()
	Register probe listeners for this object. More...

ProbeManager *	getProbeManager ()
	Get the probe manager for this object. More...

virtual Port &	getPort (const std::string &if_name, PortID idx=InvalidPortID)
	Get a port with a given name and index. More...

virtual void	startup ()
	startup() is the final initialization call before simulation. More...

DrainState	drain () override
	Provide a default implementation of the drain interface for objects that don't need draining. More...

virtual void	memWriteback ()
	Write back dirty buffers to memory using functional writes. More...

virtual void	memInvalidate ()
	Invalidate the contents of memory buffers. More...

void	serialize (CheckpointOut &cp) const override
	Serialize an object. More...

void	unserialize (CheckpointIn &cp) override
	Unserialize an object. More...

Public Member Functions inherited from 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. More...

void	setCurTick (Tick newVal)

	EventManager (EventManager &em)
	Event manger manages events in the event queue. More...

	EventManager (EventManager *em)

	EventManager (EventQueue *eq)

Public Member Functions inherited from Serializable
	Serializable ()

virtual	~Serializable ()

void	serializeSection (CheckpointOut &cp, const char *name) const
	Serialize an object into a new section. More...

void	serializeSection (CheckpointOut &cp, const std::string &name) const

void	unserializeSection (CheckpointIn &cp, const char *name)
	Unserialize an a child object. More...

void	unserializeSection (CheckpointIn &cp, const std::string &name)

Public Member Functions inherited from Drainable
DrainState	drainState () const
	Return the current drain state of an object. More...

virtual void	notifyFork ()
	Notify a child process of a fork. More...

Public Member Functions inherited from Stats::Group
	Group (Group parent, const char name=nullptr)
	Construct a new statistics group. More...

virtual	~Group ()

virtual void	regStats ()
	Callback to set stat parameters. More...

virtual void	resetStats ()
	Callback to reset stats. More...

virtual void	preDumpStats ()
	Callback before stats are dumped. More...

void	addStat (Stats::Info *info)
	Register a stat with this group. More...

const std::map< std::string, Group * > &	getStatGroups () const
	Get all child groups associated with this object. More...

const std::vector< Info * > &	getStats () const
	Get all stats associated with this object. More...

void	addStatGroup (const char name, Group block)
	Add a stat block as a child of this block. More...

const Info *	resolveStat (std::string name) const
	Resolve a stat by its name within this group. More...

	Group ()=delete

	Group (const Group &)=delete

Group &	operator= (const Group &)=delete

Static Public Attributes
static constexpr auto	NoCapableFU = -2

static constexpr auto	NoFreeFU = -1

Private Types
typedef std::vector< FuncUnit * >::iterator	fuListIterator

Private Attributes
std::array< Cycles, Num_OpClasses >	maxOpLatencies
	Maximum op execution latencies, per op class. More...

std::array< bool, Num_OpClasses >	pipelined
	Whether op is pipelined or not. More...

std::bitset< Num_OpClasses >	capabilityList
	Bitvector listing capabilities of this FU pool. More...

std::vector< bool >	unitBusy
	Bitvector listing which FUs are busy. More...

std::vector< int >	unitsToBeFreed
	List of units to be freed at the end of this cycle. More...

FUIdxQueue	fuPerCapList [Num_OpClasses]
	Per op class queues of FUs that provide that capability. More...

int	numFU
	Number of FUs. More...

std::vector< FuncUnit * >	funcUnits
	Functional units. More...

Additional Inherited Members
Static Public Member Functions inherited from SimObject
static void	serializeAll (CheckpointOut &cp)
	Serialize all SimObjects in the system. More...

static SimObject *	find (const char *name)
	Find the SimObject with the given name and return a pointer to it. More...

Static Public Member Functions inherited from Serializable
static const std::string &	currentSection ()
	Gets the fully-qualified name of the active section. More...

static void	serializeAll (const std::string &cpt_dir)
	Serializes all the SimObjects. More...

static void	unserializeGlobals (CheckpointIn &cp)

Protected Member Functions inherited from Drainable
	Drainable ()

virtual	~Drainable ()

virtual void	drainResume ()
	Resume execution after a successful drain. More...

void	signalDrainDone () const
	Signal that an object is drained. More...

Protected Attributes inherited from SimObject
const SimObjectParams *	_params
	Cached copy of the object parameters. More...

Protected Attributes inherited from EventManager
EventQueue *	eventq
	A pointer to this object's event queue. More...

Detailed Description

Pool of FU's, specific to the new CPU model.

The old FU pool had lists of free units and busy units, and whenever a FU was needed it would iterate through the free units to find a FU that provided the capability. This pool has lists of units specific to each of the capabilities, and whenever a FU is needed, it iterates through that list to find a free unit. The previous FU pool would have to be ticked each cycle to update which units became free. This FU pool lets the IEW stage handle freeing units, which frees them as their scheduled execution events complete. This limits units in this model to either have identical issue and op latencies, or 1 cycle issue latencies.

Definition at line 69 of file fu_pool.hh.

Member Typedef Documentation

◆ fuListIterator

typedef std::vector<FuncUnit *>::iterator FUPool::fuListIterator

private

Definition at line 127 of file fu_pool.hh.

◆ Params

typedef FUPoolParams FUPool::Params

Definition at line 130 of file fu_pool.hh.

Constructor & Destructor Documentation

◆ FUPool()

FUPool::FUPool ( const Params * p )

Constructs a FU pool.

Definition at line 82 of file fu_pool.cc.

References FUPool::FUIdxQueue::addFU(), ArmISA::c, capabilityList, PowerISA::fu, funcUnits, fuPerCapList, ArmISA::i, ArmISA::j, MipsISA::k, maxOpLatencies, FuncUnit::name, numFU, MipsISA::p, pipelined, ArmISA::s, and unitBusy.

◆ ~FUPool()

FUPool::~FUPool ( )

Definition at line 72 of file fu_pool.cc.

References ArmISA::i.

Member Function Documentation

◆ dump()

void FUPool::dump ( )

Debugging function used to dump FU information.

Definition at line 206 of file fu_pool.cc.

References funcUnits, ArmISA::i, SimObject::name(), numFU, and unitBusy.

◆ freeUnitNextCycle()

void FUPool::freeUnitNextCycle ( int fu_idx )

Frees a FU at the end of this cycle.

Definition at line 186 of file fu_pool.cc.

References unitBusy, and unitsToBeFreed.

◆ getOpLatency()

Cycles FUPool::getOpLatency ( OpClass capability )

inline

Returns the operation execution latency of the given capability.

Definition at line 162 of file fu_pool.hh.

References maxOpLatencies.

◆ getUnit()

int FUPool::getUnit ( OpClass capability )

Gets a FU providing the requested capability.

Will mark the unit as busy, but leaves the freeing of the unit up to the IEW stage.

Parameters

capability The capability requested.

Returns: Returns NoCapableFU if the FU pool does not have the capability, NoFreeFU if there is no free FU, and the FU's index otherwise.

Definition at line 158 of file fu_pool.cc.

References capabilityList, fuPerCapList, FUPool::FUIdxQueue::getFU(), numFU, and unitBusy.

◆ isDrained()

bool FUPool::isDrained ( ) const

Have all the FUs drained?

Definition at line 240 of file fu_pool.cc.

References ArmISA::i, numFU, and unitBusy.

◆ isPipelined()

bool FUPool::isPipelined ( OpClass capability )

inline

Returns the issue latency of the given capability.

Definition at line 167 of file fu_pool.hh.

References pipelined.

◆ processFreeUnits()

void FUPool::processFreeUnits ( )

Frees all FUs on the list.

Definition at line 193 of file fu_pool.cc.

References unitBusy, and unitsToBeFreed.

◆ size()

int FUPool::size ( )

inline

Returns the total number of FUs.

Definition at line 156 of file fu_pool.hh.

References numFU.

◆ takeOverFrom()

void FUPool::takeOverFrom ( )

inline

Takes over from another CPU's thread.

Definition at line 175 of file fu_pool.hh.

Member Data Documentation

◆ capabilityList

std::bitset<Num_OpClasses> FUPool::capabilityList

private

Bitvector listing capabilities of this FU pool.

Definition at line 78 of file fu_pool.hh.

Referenced by FUPool(), and getUnit().

◆ funcUnits

std::vector<FuncUnit *> FUPool::funcUnits

private

Functional units.

Definition at line 125 of file fu_pool.hh.

Referenced by dump(), and FUPool().

◆ fuPerCapList

FUIdxQueue FUPool::fuPerCapList[Num_OpClasses]

private

Per op class queues of FUs that provide that capability.

Definition at line 119 of file fu_pool.hh.

Referenced by FUPool(), and getUnit().

◆ maxOpLatencies

std::array<Cycles, Num_OpClasses> FUPool::maxOpLatencies

private

Maximum op execution latencies, per op class.

Definition at line 73 of file fu_pool.hh.

Referenced by FUPool(), and getOpLatency().

◆ NoCapableFU

constexpr auto FUPool::NoCapableFU = -2

staticconstexpr

Definition at line 135 of file fu_pool.hh.

Referenced by InstructionQueue< Impl >::scheduleReadyInsts().

◆ NoFreeFU

constexpr auto FUPool::NoFreeFU = -1

staticconstexpr

Definition at line 136 of file fu_pool.hh.

Referenced by InstructionQueue< Impl >::scheduleReadyInsts().

◆ numFU

int FUPool::numFU

private

Number of FUs.

Definition at line 122 of file fu_pool.hh.

Referenced by dump(), FUPool(), getUnit(), isDrained(), and size().

◆ pipelined

std::array<bool, Num_OpClasses> FUPool::pipelined

private

Whether op is pipelined or not.

Definition at line 75 of file fu_pool.hh.

Referenced by FUPool(), and isPipelined().

◆ unitBusy

std::vector<bool> FUPool::unitBusy

private

Bitvector listing which FUs are busy.

Definition at line 81 of file fu_pool.hh.

Referenced by dump(), freeUnitNextCycle(), FUPool(), getUnit(), isDrained(), and processFreeUnits().

◆ unitsToBeFreed

std::vector<int> FUPool::unitsToBeFreed

private

List of units to be freed at the end of this cycle.

Definition at line 84 of file fu_pool.hh.

Referenced by freeUnitNextCycle(), and processFreeUnits().

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

cpu/o3/fu_pool.hh
cpu/o3/fu_pool.cc

Classes

Public Types

Public Member Functions

Static Public Attributes

Private Types

Private Attributes

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ fuListIterator

◆ Params

Constructor & Destructor Documentation

◆ FUPool()

◆ ~FUPool()

Member Function Documentation

◆ dump()

◆ freeUnitNextCycle()

◆ getOpLatency()

◆ getUnit()

◆ isDrained()

◆ isPipelined()

◆ processFreeUnits()

◆ size()

◆ takeOverFrom()

Member Data Documentation

◆ capabilityList

◆ funcUnits

◆ fuPerCapList

◆ maxOpLatencies

◆ NoCapableFU

◆ NoFreeFU

◆ numFU

◆ pipelined

◆ unitBusy

◆ unitsToBeFreed