The Prio qdisc is a simple classful queueing discipline that contains an arbitrary number of classes of differing priority. More...

#include "prio-queue-disc.h"

Inheritance diagram for ns3::PrioQueueDisc:

Collaboration diagram for ns3::PrioQueueDisc:

Public Member Functions
	PrioQueueDisc ()
	PrioQueueDisc constructor.

	~PrioQueueDisc () override

uint16_t	GetBandForPriority (uint8_t prio) const
	Get the band (class) assigned to packets with specified priority.

void	SetBandForPriority (uint8_t prio, uint16_t band)
	Set the band (class) assigned to packets with specified priority.

Public Member Functions inherited from ns3::QueueDisc
	QueueDisc (const QueueDisc &)=delete

	QueueDisc (QueueDiscSizePolicy policy, QueueSizeUnit unit)
	Constructor.

	QueueDisc (QueueDiscSizePolicy policy=QueueDiscSizePolicy::SINGLE_INTERNAL_QUEUE)
	Constructor.

	~QueueDisc () override

void	AddInternalQueue (Ptr< InternalQueue > queue)
	Add an internal queue to the tail of the list of queues.

void	AddPacketFilter (Ptr< PacketFilter > filter)
	Add a packet filter to the tail of the list of filters used to classify packets.

void	AddQueueDiscClass (Ptr< QueueDiscClass > qdClass)
	Add a queue disc class to the tail of the list of classes.

int32_t	Classify (Ptr< QueueDiscItem > item)
	Classify a packet by calling the packet filters, one at a time, until either a filter able to classify the packet is found or all the filters have been processed.

Ptr< QueueDiscItem >	Dequeue ()
	Extract from the queue disc the packet that has been dequeued by calling Peek, if any, or call the private DoDequeue method (which must be implemented by derived classes) to dequeue a packet, otherwise.

bool	Enqueue (Ptr< QueueDiscItem > item)
	Pass a packet to store to the queue discipline.

QueueSize	GetCurrentSize () const
	Get the current size of the queue disc in bytes, if operating in bytes mode, or packets, otherwise.

Ptr< InternalQueue >	GetInternalQueue (std::size_t i) const
	Get the i-th internal queue.

QueueSize	GetMaxSize () const
	Get the maximum size of the queue disc.

uint32_t	GetNBytes () const
	Get the amount of bytes stored by the queue disc.

Ptr< NetDeviceQueueInterface >	GetNetDeviceQueueInterface () const

std::size_t	GetNInternalQueues () const
	Get the number of internal queues.

std::size_t	GetNPacketFilters () const
	Get the number of packet filters.

uint32_t	GetNPackets () const
	Get the number of packets stored by the queue disc.

std::size_t	GetNQueueDiscClasses () const
	Get the number of queue disc classes.

Ptr< PacketFilter >	GetPacketFilter (std::size_t i) const
	Get the i-th packet filter.

Ptr< QueueDiscClass >	GetQueueDiscClass (std::size_t i) const
	Get the i-th queue disc class.

virtual uint32_t	GetQuota () const
	Get the maximum number of dequeue operations following a packet enqueue.

SendCallback	GetSendCallback () const

const Stats &	GetStats ()
	Retrieve all the collected statistics.

virtual WakeMode	GetWakeMode () const
	When setting up the wake callbacks on the netdevice queues, it is necessary to determine which queue disc (the root queue disc or one of its children) should be activated when the netdevice wakes one of its transmission queues.

QueueDisc &	operator= (const QueueDisc &)=delete

Ptr< const QueueDiscItem >	Peek ()
	Get a copy of the next packet the queue discipline will extract.

void	Run ()
	Modelled after the Linux function __qdisc_run (net/sched/sch_generic.c) Dequeues multiple packets, until a quota is exceeded or sending a packet to the device failed.

bool	SetMaxSize (QueueSize size)
	Set the maximum size of the queue disc.

void	SetNetDeviceQueueInterface (Ptr< NetDeviceQueueInterface > ndqi)

virtual void	SetQuota (const uint32_t quota)
	Set the maximum number of dequeue operations following a packet enqueue.

void	SetSendCallback (SendCallback func)

Public Member Functions inherited from ns3::Object
	Object ()
	Constructor.

	~Object () override
	Destructor.

void	AggregateObject (Ptr< Object > other)
	Aggregate two Objects together.

void	Dispose ()
	Dispose of this Object.

AggregateIterator	GetAggregateIterator () const
	Get an iterator to the Objects aggregated to this one.

TypeId	GetInstanceTypeId () const override
	Get the most derived TypeId for this Object.

template<typename T >
Ptr< T >	GetObject () const
	Get a pointer to the requested aggregated Object.

template<>
Ptr< Object >	GetObject () const
	Specialization of () for objects of type ns3::Object.

template<typename T >
Ptr< T >	GetObject (TypeId tid) const
	Get a pointer to the requested aggregated Object by TypeId.

template<>
Ptr< Object >	GetObject (TypeId tid) const
	Specialization of (TypeId tid) for objects of type ns3::Object.

void	Initialize ()
	Invoke DoInitialize on all Objects aggregated to this one.

bool	IsInitialized () const
	Check if the object has been initialized.

void	UnidirectionalAggregateObject (Ptr< Object > other)
	Aggregate an Object to another Object.

Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
	SimpleRefCount ()
	Default constructor.

	SimpleRefCount (const SimpleRefCount &o)
	Copy constructor.

uint32_t	GetReferenceCount () const
	Get the reference count of the object.

SimpleRefCount &	operator= (const SimpleRefCount &o)
	Assignment operator.

void	Ref () const
	Increment the reference count.

void	Unref () const
	Decrement the reference count.

Public Member Functions inherited from ns3::ObjectBase
virtual	~ObjectBase ()
	Virtual destructor.

void	GetAttribute (std::string name, AttributeValue &value, bool permissive=false) const
	Get the value of an attribute, raising fatal errors if unsuccessful.

bool	GetAttributeFailSafe (std::string name, AttributeValue &value) const
	Get the value of an attribute without raising errors.

void	SetAttribute (std::string name, const AttributeValue &value)
	Set a single attribute, raising fatal errors if unsuccessful.

bool	SetAttributeFailSafe (std::string name, const AttributeValue &value)
	Set a single attribute without raising errors.

bool	TraceConnect (std::string name, std::string context, const CallbackBase &cb)
	Connect a TraceSource to a Callback with a context.

bool	TraceConnectWithoutContext (std::string name, const CallbackBase &cb)
	Connect a TraceSource to a Callback without a context.

bool	TraceDisconnect (std::string name, std::string context, const CallbackBase &cb)
	Disconnect from a TraceSource a Callback previously connected with a context.

bool	TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb)
	Disconnect from a TraceSource a Callback previously connected without a context.

Static Public Member Functions
static TypeId	GetTypeId ()
	Get the type ID.

Static Public Member Functions inherited from ns3::QueueDisc
static TypeId	GetTypeId ()
	Get the type ID.

Static Public Member Functions inherited from ns3::Object
static TypeId	GetTypeId ()
	Register this type.

Static Public Member Functions inherited from ns3::ObjectBase
static TypeId	GetTypeId ()
	Get the type ID.

Private Member Functions
bool	CheckConfig () override
	Check whether the current configuration is correct.

Ptr< QueueDiscItem >	DoDequeue () override
	This function actually extracts a packet from the queue disc.

bool	DoEnqueue (Ptr< QueueDiscItem > item) override
	This function actually enqueues a packet into the queue disc.

Ptr< const QueueDiscItem >	DoPeek () override
	Return a copy of the next packet the queue disc will extract.

void	InitializeParams () override
	Initialize parameters (if any) before the first packet is enqueued.

Private Attributes
Priomap	m_prio2band
	Priority to band mapping.

Additional Inherited Members
Public Types inherited from ns3::QueueDisc
typedef Queue< QueueDiscItem >	InternalQueue
	Internal queues store QueueDiscItem objects.

typedef std::function< void(Ptr< QueueDiscItem >)>	SendCallback
	Callback invoked to send a packet to the receiving object when Run is called.

enum	WakeMode { WAKE_ROOT = 0x00 , WAKE_CHILD = 0x01 }
	Used to determine whether the queue disc itself or its children must be activated when a netdevice wakes a transmission queue. More...

Static Public Attributes inherited from ns3::QueueDisc
static constexpr const char *	CHILD_QUEUE_DISC_DROP
	Packet dropped by a child queue disc.

static constexpr const char *	CHILD_QUEUE_DISC_MARK
	Packet marked by a child queue disc.

static constexpr const char *	INTERNAL_QUEUE_DROP
	Packet dropped by an internal queue.

Protected Member Functions inherited from ns3::QueueDisc
void	DoDispose () override
	Dispose of the object.

void	DoInitialize () override
	Check whether the configuration is correct and initialize parameters.

void	DropAfterDequeue (Ptr< const QueueDiscItem > item, const char *reason)
	Perform the actions required when the queue disc is notified of a packet dropped after dequeue.

void	DropBeforeEnqueue (Ptr< const QueueDiscItem > item, const char *reason)
	Perform the actions required when the queue disc is notified of a packet dropped before enqueue.

bool	Mark (Ptr< QueueDiscItem > item, const char *reason)
	Marks the given packet and, if successful, updates the counters associated with the given reason.

Protected Member Functions inherited from ns3::Object
	Object (const Object &o)
	Copy an Object.

virtual void	NotifyNewAggregate ()
	Notify all Objects aggregated to this one of a new Object being aggregated.

Protected Member Functions inherited from ns3::ObjectBase
void	ConstructSelf (const AttributeConstructionList &attributes)
	Complete construction of ObjectBase; invoked by derived classes.

virtual void	NotifyConstructionCompleted ()
	Notifier called once the ObjectBase is fully constructed.

Related Symbols inherited from ns3::ObjectBase
static TypeId	GetObjectIid ()
	Ensure the TypeId for ObjectBase gets fully configured to anchor the inheritance tree properly.

Detailed Description

The Prio qdisc is a simple classful queueing discipline that contains an arbitrary number of classes of differing priority.

The classes are dequeued in numerical descending order of priority. By default, three Fifo queue discs are created, unless the user provides (at least two) child queue discs.

If no packet filter is installed or able to classify a packet, then the packet is assigned a priority band based on its priority (modulo 16), which is used as an index into an array called priomap. If a packet is classified by a packet filter and the returned value is non-negative and less than the number of priority bands, then the packet is assigned the priority band corresponding to the value returned by the packet filter. Otherwise, the packet is assigned the priority band specified by the first element of the priomap array.

Definition at line 40 of file prio-queue-disc.h.

Constructor & Destructor Documentation

◆ PrioQueueDisc()

ns3::PrioQueueDisc::PrioQueueDisc ( )

PrioQueueDisc constructor.

Definition at line 66 of file prio-queue-disc.cc.

References NS_LOG_FUNCTION.

◆ ~PrioQueueDisc()

ns3::PrioQueueDisc::~PrioQueueDisc ( )

override

Definition at line 72 of file prio-queue-disc.cc.

References NS_LOG_FUNCTION.

Member Function Documentation

◆ CheckConfig()

bool ns3::PrioQueueDisc::CheckConfig ( )

overrideprivatevirtual

Check whether the current configuration is correct.

Default objects (such as internal queues) might be created by this method to ensure the configuration is correct. This method is automatically called at simulation initialization time, and it is called before the InitializeParams () method. It is appropriate to promote parameter initialization to this method if it aids in checking for correct configuration.

See also: QueueDisc::InitializeParams

Returns: true if the configuration is correct, false otherwise

Implements ns3::QueueDisc.

Definition at line 183 of file prio-queue-disc.cc.

References ns3::QueueDisc::AddQueueDiscClass(), ns3::ObjectFactory::Create(), ns3::CreateObject(), ns3::QueueDisc::GetNInternalQueues(), ns3::QueueDisc::GetNQueueDiscClasses(), NS_LOG_ERROR, NS_LOG_FUNCTION, and ns3::ObjectFactory::SetTypeId().

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◆ DoDequeue()

Ptr< QueueDiscItem > ns3::PrioQueueDisc::DoDequeue ( )

overrideprivatevirtual

This function actually extracts a packet from the queue disc.

Returns: 0 if the operation was not successful; the item otherwise.

Implements ns3::QueueDisc.

Definition at line 139 of file prio-queue-disc.cc.

References ns3::QueueDisc::Dequeue(), ns3::QueueDisc::GetNPackets(), ns3::QueueDisc::GetNQueueDiscClasses(), ns3::QueueDisc::GetQueueDiscClass(), NS_LOG_FUNCTION, and NS_LOG_LOGIC.

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◆ DoEnqueue()

bool ns3::PrioQueueDisc::DoEnqueue ( Ptr< QueueDiscItem > item )

overrideprivatevirtual

This function actually enqueues a packet into the queue disc.

Parameters

item	item to enqueue

Returns: True if the operation was successful; false otherwise

Implements ns3::QueueDisc.

Definition at line 98 of file prio-queue-disc.cc.

References ns3::QueueDisc::Classify(), ns3::QueueDisc::GetNPackets(), ns3::QueueDisc::GetNQueueDiscClasses(), ns3::SocketPriorityTag::GetPriority(), ns3::QueueDisc::GetQueueDiscClass(), m_prio2band, NS_ASSERT_MSG, NS_LOG_DEBUG, NS_LOG_FUNCTION, NS_LOG_LOGIC, and ns3::PacketFilter::PF_NO_MATCH.

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◆ DoPeek()

Ptr< const QueueDiscItem > ns3::PrioQueueDisc::DoPeek ( )

overrideprivatevirtual

Return a copy of the next packet the queue disc will extract.

The implementation of this method is based on the qdisc_peek_dequeued function of the Linux kernel, which dequeues a packet and retains it in the queue disc as a requeued packet. The packet is not traced as requeued, nor is the total count of requeued packets increased. The packet is still considered to be part of the queue disc and the dequeue trace is fired when Dequeue is called and the packet is actually extracted from the queue disc.

This approach is especially recommended for queue discs for which it is not obvious what is the next packet that will be dequeued (e.g., queue discs having multiple internal queues or child queue discs or queue discs that drop packets after dequeue). Subclasses can however provide their own implementation of this method that overrides the default one.

Returns: 0 if the operation was not successful; the packet otherwise.

Reimplemented from ns3::QueueDisc.

Definition at line 161 of file prio-queue-disc.cc.

References ns3::QueueDisc::GetNPackets(), ns3::QueueDisc::GetNQueueDiscClasses(), ns3::QueueDisc::GetQueueDiscClass(), NS_LOG_FUNCTION, NS_LOG_LOGIC, and ns3::QueueDisc::Peek().

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◆ GetBandForPriority()

uint16_t ns3::PrioQueueDisc::GetBandForPriority ( uint8_t prio ) const

Get the band (class) assigned to packets with specified priority.

Parameters

prio	the priority of packets (a value between 0 and 15).

Returns: the band assigned to packets.

Definition at line 88 of file prio-queue-disc.cc.

References m_prio2band, NS_ASSERT_MSG, and NS_LOG_FUNCTION.

◆ GetTypeId()

TypeId ns3::PrioQueueDisc::GetTypeId ( )

static

Get the type ID.

Returns: the object TypeId

Definition at line 51 of file prio-queue-disc.cc.

References m_prio2band, ns3::MakePriomapAccessor(), ns3::MakePriomapChecker(), and ns3::TypeId::SetParent().

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◆ InitializeParams()

void ns3::PrioQueueDisc::InitializeParams ( )

overrideprivatevirtual

Initialize parameters (if any) before the first packet is enqueued.

This method is automatically called at simulation initialization time, after the CheckConfig() method has been called.

See also: QueueDisc::CheckConfig

Implements ns3::QueueDisc.

Definition at line 217 of file prio-queue-disc.cc.

References NS_LOG_FUNCTION.

◆ SetBandForPriority()

void ns3::PrioQueueDisc::SetBandForPriority	(	uint8_t	prio,
		uint16_t	band )

Set the band (class) assigned to packets with specified priority.

Parameters

prio	the priority of packets (a value between 0 and 15).
band	the band assigned to packets.

Definition at line 78 of file prio-queue-disc.cc.

References m_prio2band, NS_ASSERT_MSG, and NS_LOG_FUNCTION.

Member Data Documentation

◆ m_prio2band

Priomap ns3::PrioQueueDisc::m_prio2band

private

Priority to band mapping.

Definition at line 78 of file prio-queue-disc.h.

Referenced by DoEnqueue(), GetBandForPriority(), GetTypeId(), and SetBandForPriority().

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

src/traffic-control/model/prio-queue-disc.h
src/traffic-control/model/prio-queue-disc.cc

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ PrioQueueDisc()

◆ ~PrioQueueDisc()

Member Function Documentation

◆ CheckConfig()

◆ DoDequeue()

◆ DoEnqueue()

◆ DoPeek()

◆ GetBandForPriority()

◆ GetTypeId()

◆ InitializeParams()

◆ SetBandForPriority()

Member Data Documentation

◆ m_prio2band