The PowerDomain groups PowerState objects together to regulate their power states. More...

#include <power_domain.hh>

Inheritance diagram for gem5::PowerDomain:

Classes
struct	PowerDomainStats

Public Types
typedef PowerDomainParams	Params

Public Types inherited from gem5::SimObject
typedef SimObjectParams	Params

Public Member Functions
	PowerDomain (const PowerDomainParams &p)

	~PowerDomain () override

void	startup () override
	During startup, the list of possible power states the PowerDomain can be in is populated, the power state of the PowerDomain is set and some assertions about the PowerState objects in the Domain are checked.

void	pwrStateChangeCallback (enums::PwrState new_pwr_state, PowerState *leader)
	Register the change in power state in one of the leader.

void	addFollower (PowerState *pwr_obj) override
	Function called by a follower to register itself as a dependant of this power domain.

Public Member Functions inherited from gem5::PowerState
	PowerState (const PowerStateParams &p)

	PARAMS (PowerState)
	Parameters of PowerState object.

void	setControlledDomain (PowerDomain *pwr_dom)

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

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

void	set (enums::PwrState p)
	Change the power state of this object to the power state p.

enums::PwrState	get () const

std::string	getName () const

std::vector< double >	getWeights () const
	Returns the percentage residency for each power state.

void	computeStats ()
	Record stats values like state residency by computing the time difference from previous update.

enums::PwrState	matchPwrState (enums::PwrState p)
	Change the power state of this object to a power state equal to OR more performant than p.

std::set< enums::PwrState >	getPossibleStates () const
	Return the power states this object can be in.

Public Member Functions inherited from gem5::SimObject
const Params &	params () const

	SimObject (const Params &p)

virtual	~SimObject ()

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

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

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

Protected Attributes
gem5::PowerDomain::PowerDomainStats	stats

Protected Attributes inherited from gem5::PowerState
enums::PwrState	_currState
	To keep track of the current power state.

std::set< enums::PwrState >	possibleStates
	The possible power states this object can be in.

Tick	prvEvalTick = 0
	Last tick the power stats were calculated.

PowerDomain *	controlledDomain = nullptr
	The power domain that this power state leads, nullptr if it doesn't lead any.

gem5::PowerState::PowerStateStats	stats

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.

Private Member Functions
enums::PwrState	calculatePowerDomainState (const std::vector< enums::PwrState > &f_states={})
	Calculate the power state of the power domain, based upon the power states of the leaders.

bool	isPossiblePwrState (enums::PwrState p_state)
	Check if a given p_state is available across all leaders and followers in this domain.

void	calculatePossiblePwrStates ()
	Calculate the possible power states of the domain based upon the intersection of the power states of the individual objects within the domain.

void	setFollowerPowerStates ()
	Update the followers of the newly updated power state.

Private Attributes
std::vector< PowerState * >	leaders
	List of all leaders in the PowerDomain.

enums::PwrState	leaderTargetState
	Power state requested by the leader.

std::vector< PowerState * >	followers
	List of all followers in the PowerDomain.

const Tick	updateLatency = 1
	Latency with which power state changes of the leaders will ripple through to the followers.

MemberEventWrapper<&PowerDomain::setFollowerPowerStates >	pwrStateUpdateEvent
	Event to update the power states of the followers.

Additional Inherited Members
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.

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.

Detailed Description

The PowerDomain groups PowerState objects together to regulate their power states.

As the PowerDomain itself is a PowerState object, you can create hierarchies of PowerDomains. All objects in a power domain will be in the power state of the domain OR a more performant one.

Definition at line 59 of file power_domain.hh.

Member Typedef Documentation

◆ Params

typedef PowerDomainParams gem5::PowerDomain::Params

Definition at line 63 of file power_domain.hh.

Constructor & Destructor Documentation

◆ PowerDomain()

gem5::PowerDomain::PowerDomain ( const PowerDomainParams & p )

Definition at line 48 of file power_domain.cc.

References gem5::PowerState::_currState, fatal_if, leaders, leaderTargetState, and gem5::Named::name().

◆ ~PowerDomain()

gem5::PowerDomain::~PowerDomain ( )

inlineoverride

Definition at line 64 of file power_domain.hh.

Member Function Documentation

◆ addFollower()

void gem5::PowerDomain::addFollower ( PowerState * pwr_obj )

overridevirtual

Function called by a follower to register itself as a dependant of this power domain.

Reimplemented from gem5::PowerState.

Definition at line 69 of file power_domain.cc.

References DPRINTF, followers, and gem5::Named::name().

◆ calculatePossiblePwrStates()

void gem5::PowerDomain::calculatePossiblePwrStates ( )

private

Calculate the possible power states of the domain based upon the intersection of the power states of the individual objects within the domain.

Done at startup.

Definition at line 137 of file power_domain.cc.

References DPRINTF, isPossiblePwrState(), leaders, and gem5::PowerState::possibleStates.

Referenced by startup().

◆ calculatePowerDomainState()

enums::PwrState gem5::PowerDomain::calculatePowerDomainState ( const std::vector< enums::PwrState > & f_states = {} )

private

Calculate the power state of the power domain, based upon the power states of the leaders.

This will be called if one the leaders changes its power states. If no inputs are given, only the leaders will be polled on their power state. You can also pass a vector containing the power states which the followers returned when asked to match a certain power state (called from setFollowerPowerStates)

Definition at line 150 of file power_domain.cc.

References DPRINTF, and leaders.

Referenced by pwrStateChangeCallback(), setFollowerPowerStates(), and startup().

◆ isPossiblePwrState()

bool gem5::PowerDomain::isPossiblePwrState ( enums::PwrState p_state )

private

Check if a given p_state is available across all leaders and followers in this domain.

Definition at line 123 of file power_domain.cc.

References followers, and leaders.

Referenced by calculatePossiblePwrStates().

◆ pwrStateChangeCallback()

void gem5::PowerDomain::pwrStateChangeCallback	(	enums::PwrState	new_pwr_state,
		PowerState *	leader )

Register the change in power state in one of the leader.

The power domain will change its own power state if required and if there is a power state, it will schedule an event to update its followers

Definition at line 214 of file power_domain.cc.

References gem5::PowerState::_currState, calculatePowerDomainState(), gem5::curTick(), DPRINTF, leaderTargetState, gem5::Named::name(), gem5::PowerDomain::PowerDomainStats::numLeaderCalls, gem5::PowerDomain::PowerDomainStats::numLeaderCallsChangingState, pwrStateUpdateEvent, gem5::EventManager::schedule(), stats, and updateLatency.

Referenced by gem5::PowerState::set().

◆ setFollowerPowerStates()

void gem5::PowerDomain::setFollowerPowerStates ( )

private

Update the followers of the newly updated power state.

They are required to match the power state of the power domain i.e. go to the same power state or a more performant one

Definition at line 185 of file power_domain.cc.

References gem5::PowerState::_currState, calculatePowerDomainState(), DPRINTF, followers, leaderTargetState, gem5::Named::name(), and gem5::ArmISA::set.

Referenced by startup().

◆ startup()

void gem5::PowerDomain::startup ( )

overridevirtual

During startup, the list of possible power states the PowerDomain can be in is populated, the power state of the PowerDomain is set and some assertions about the PowerState objects in the Domain are checked.

Reimplemented from gem5::SimObject.

Definition at line 76 of file power_domain.cc.

References calculatePossiblePwrStates(), calculatePowerDomainState(), DPRINTF, fatal_if, followers, leaders, leaderTargetState, gem5::Named::name(), and setFollowerPowerStates().

Member Data Documentation

◆ followers

std::vector<PowerState*> gem5::PowerDomain::followers

private

List of all followers in the PowerDomain.

The power state of the domain will determine the power state of the followers. A follower cannot change its power state independently.

Definition at line 143 of file power_domain.hh.

Referenced by addFollower(), isPossiblePwrState(), setFollowerPowerStates(), and startup().

◆ leaders

std::vector<PowerState*> gem5::PowerDomain::leaders

private

List of all leaders in the PowerDomain.

A leader can independently change its power state and does not depend on the PowerDomain to change its power state. A leader needs to be a PowerState object and can also be another PowerDomain. Each PowerDomain needs to have at least one leader.

Definition at line 129 of file power_domain.hh.

Referenced by calculatePossiblePwrStates(), calculatePowerDomainState(), isPossiblePwrState(), PowerDomain(), and startup().

◆ leaderTargetState

enums::PwrState gem5::PowerDomain::leaderTargetState

private

Power state requested by the leader.

This is not necessarily the power state of the domain as whole (as that one depends on the matched power states of the followers

Definition at line 136 of file power_domain.hh.

Referenced by PowerDomain(), pwrStateChangeCallback(), setFollowerPowerStates(), and startup().

◆ pwrStateUpdateEvent

MemberEventWrapper<&PowerDomain::setFollowerPowerStates> gem5::PowerDomain::pwrStateUpdateEvent

private

Event to update the power states of the followers.

Definition at line 155 of file power_domain.hh.

Referenced by pwrStateChangeCallback().

◆ stats

gem5::PowerDomain::PowerDomainStats gem5::PowerDomain::stats

protected

Referenced by pwrStateChangeCallback().

◆ updateLatency

const Tick gem5::PowerDomain::updateLatency = 1

private

Latency with which power state changes of the leaders will ripple through to the followers.

Definition at line 149 of file power_domain.hh.

Referenced by pwrStateChangeCallback().

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

sim/power_domain.hh
sim/power_domain.cc

Classes

Public Types

Public Member Functions

Protected Attributes

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ Params

Constructor & Destructor Documentation

◆ PowerDomain()

◆ ~PowerDomain()

Member Function Documentation

◆ addFollower()

◆ calculatePossiblePwrStates()

◆ calculatePowerDomainState()

◆ isPossiblePwrState()

◆ pwrStateChangeCallback()

◆ setFollowerPowerStates()

◆ startup()

Member Data Documentation

◆ followers

◆ leaders

◆ leaderTargetState

◆ pwrStateUpdateEvent

◆ stats

◆ updateLatency