DREAM::Channel Class Reference

Real-time event Channel . More...

#include <Task.h>

Inheritance diagram for DREAM::Channel:


Public Member Functions
	Channel (const std::string &id, DREAM::Thread *thread_ptr, uint delay, uint buffersize)
	Constructor.
	Channel (const std::string &id, DREAM::Thread *thread_ptr, uint delay, uint bcdelay, uint buffersize)
	Constructor.
	Channel (const DREAM::Channel &channel)
	Copy constructor for Channels.
virtual	~Channel ()
	Destructor.
virtual void	add_dependent (DREAM::Node *node_ptr) throw (DREAM::Exception)
	Adds a dependent Node to the current Channel.
virtual uint	bcet () const
	Returns the best case delay.
virtual void	branching_point ()
	Sets the new execution time if branching points were found.
virtual DREAM::Context	context () const
	Returns whether the Channel uses the best case or worst case delay for the simulation.
virtual void	context (DREAM::Context context)
	Sets the Channel to use the specified context (e.g.
virtual void	clock_exec_reset ()
	Reset execution clock value - clock_exec_.
virtual void	clock_step (double clock_step)
	Models the passing of time.
virtual void	consume ()
	Consumes an event received from an event source.
virtual bool	idle_dependents () const
	Returns true if all the dependents are idle.
virtual double	next_event ()
	Tells when the Channel will generate the next event.
virtual void	next_et (double next_et)
	Sets the next execution time when the context is branchingpoint.
virtual void	publish ()
	Publishes an event to dependent tasks.
virtual void	reset ()
	Resets Timer (when restarting the simulation).
virtual void	take_transitions ()
	Takes state transitions.
virtual void	visitor_map (DREAM::NODE_MAP task_map, DREAM::NODE_MAP channel_map, DREAM::NODE_MAP *timer_map)
	This function fills the IDs (names) of tasks, channels and timers to the parameter lists.
virtual void	visitor_uppaal (DREAM::NODE_MAP task_map, DREAM::NODE_MAP channel_map, DREAM::NODE_MAP *timer_map, std::ofstream &f_stream)
	This function is part of the Uppaal system description generator.
virtual uint	wcet () const
	Returns delay_.
Private Types
enum	State { idle, wait }
	State of the Channel as specified by the DRE Semantic Domain. More...
Private Attributes
uint	bcdelay_
	Best case delay.
DREAM::Context	context_
	Specifies whether best case, worst case, or a random value is used for the execution time during the simulation.
uint	buffer_
	Buffer of the event channel storing events.
uint	buffersize_
	Specifies the size of the buffer.
uint	delay_
	Worst case delay of the event channel.
double	et_
	The execution time.
double	next_et_
	The next execution time when the context is branchingpoint.
DREAM::Node *	source_ptr_
	Reference to the event source.
enum DREAM::Channel::State	state_
	State of the Channel as specified by the DRE Semantic Domain.

Detailed Description

Real-time event Channel .

This class is the implementation of the Channel in the DRE Semantic Domain.

Definition at line 646 of file Task.h.

Member Enumeration Documentation

enum DREAM::Channel::State [private]

State of the Channel as specified by the DRE Semantic Domain.

Enumerator:

idle
wait

Definition at line 850 of file Task.h.

Constructor & Destructor Documentation

DREAM::Channel::Channel	(	const std::string &	id,
		DREAM::Thread *	thread_ptr,
		uint	delay,
		uint	buffersize
	)

Constructor.

Parameters:

	id	specifies the name of the event channel.
	thread_ptr	defines the mapping of the Channel to a platform processor.
	delay	is the delay of the event channel.
	buffersize	specifies the size of the event channel buffer. Use '0' for no limit.

Definition at line 853 of file Task.cpp.

DREAM::Channel::Channel	(	const std::string &	id,
		DREAM::Thread *	thread_ptr,
		uint	delay,
		uint	bcdelay,
		uint	buffersize
	)

Constructor.

Parameters:

	id	specifies the name of the event channel.
	thread_ptr	defines the mapping of the Channel to a platform processor.
	delay	is the worst case delay of the event channel.
	bcdelay	is the best case delay of the event channel.
	buffersize	specifies the size of the event channel buffer. Use '0' for no limit.

Definition at line 868 of file Task.cpp.

DREAM::Channel::Channel ( const DREAM::Channel & channel )

Copy constructor for Channels.

Parameters:

channel

is a pointer to the channel to be copied.

Definition at line 885 of file Task.cpp.

DREAM::Channel::~Channel ( ) [virtual]

Destructor.

Definition at line 900 of file Task.cpp.

Member Function Documentation

void DREAM::Channel::add_dependent ( DREAM::Node * node_ptr ) throw (DREAM::Exception) [virtual]

Adds a dependent Node to the current Channel.

This function also ensures that Channels cannot have more than 1 dependents.

Parameters:

node_ptr

is the pointer to the dependent Node to be added.

Reimplemented from DREAM::Node.

Definition at line 904 of file Task.cpp.

uint DREAM::Channel::bcet ( ) const [inline, virtual]

Returns the best case delay.

bcet () name is used to provide a unique interface for DREAM::Node inherited classes.

Reimplemented from DREAM::Node.

Definition at line 917 of file Task.cpp.

void DREAM::Channel::branching_point ( ) [inline, virtual]

Sets the new execution time if branching points were found.

Reimplemented from DREAM::Node.

Definition at line 928 of file Task.cpp.

References DREAM::bestcase, and DREAM::branchingpoint.

DREAM::Context DREAM::Channel::context ( ) const [inline, virtual]

Returns whether the Channel uses the best case or worst case delay for the simulation.

Returns:: the context of the Channel.

Reimplemented from DREAM::Node.

Definition at line 1016 of file Task.cpp.

void DREAM::Channel::context ( DREAM::Context context ) [inline, virtual]

Sets the Channel to use the specified context (e.g.

in the simulation).

Parameters:

context

is the context assumed.

Reimplemented from DREAM::Node.

Definition at line 1026 of file Task.cpp.

void DREAM::Channel::clock_exec_reset ( ) [inline, virtual]

Reset execution clock value - clock_exec_.

Reimplemented from DREAM::Node.

Definition at line 945 of file Task.cpp.

References bcdelay_, DREAM::bestcase, DREAM::Node::clock_exec_, context_, delay_, et_, DREAM::random(), DREAM::randomcase, and DREAM::worstcase.

Referenced by reset().

void DREAM::Channel::clock_step ( double clock_step ) [inline, virtual]

Models the passing of time.

Increments local clock clock_exec_.

Parameters:

clock_step

specifies by how much do we have to increment the time.

Reimplemented from DREAM::Node.

Definition at line 958 of file Task.cpp.

References bcdelay_, Option::branching_, DREAM::branchingpoint, buffer_, DREAM::Node::clock_exec_, context_, delay_, DREAM::Node::id_, next_et_, DREAM::System::relevant_event(), DREAM::Node::remote_dep_, DREAM::Thread::scheduler(), DREAM::Scheduler::system(), DREAM::Node::thread_ptr_, DREAM::Thread::trace(), and DREAM::worstcase.

void DREAM::Channel::consume ( ) [inline, virtual]

Consumes an event received from an event source.

This function is called by the publish () function of the event source and triggers state transitions. The take_transitions () function will take the enabled transitions.

Reimplemented from DREAM::Node.

Definition at line 993 of file Task.cpp.

References DREAM::idle.

bool DREAM::Channel::idle_dependents ( ) const [inline, virtual]

Returns true if all the dependents are idle.

Definition at line 1036 of file Task.cpp.

double DREAM::Channel::next_event ( ) [inline, virtual]

Tells when the Channel will generate the next event.

Returns:: Time remaining till the next event generation (when clock_exec_ == delay_ and buffer_ != 0).

Reimplemented from DREAM::Node.

Definition at line 1048 of file Task.cpp.

References buffer_, DREAM::Node::clock_exec_, et_, state_, and wait.

void DREAM::Channel::next_et ( double next_et ) [inline, virtual]

Sets the next execution time when the context is branchingpoint.

Reimplemented from DREAM::Node.

Definition at line 1060 of file Task.cpp.

void DREAM::Channel::publish ( ) [inline, virtual]

Publishes an event to dependent tasks.

This function models synchronous event propagation by calling the consume () functions of all the dependent Nodes.

Reimplemented from DREAM::Node.

Definition at line 1071 of file Task.cpp.

References Option::verbose1_.

void DREAM::Channel::reset ( ) [inline, virtual]

Resets Timer (when restarting the simulation).

Reimplemented from DREAM::Node.

Definition at line 1087 of file Task.cpp.

References buffer_, clock_exec_reset(), idle, and state_.

void DREAM::Channel::take_transitions ( ) [inline, virtual]

Takes state transitions.

This function implements the state transitions of a Channel as specified by the DRE Semantic Domain. Transitions can be triggered by events coming from other Tasks, Timers or Schedulers.

Reimplemented from DREAM::Node.

Definition at line 1098 of file Task.cpp.

References DREAM::idle.

void DREAM::Channel::visitor_map	(	DREAM::NODE_MAP *	task_map,
		DREAM::NODE_MAP *	channel_map,
		DREAM::NODE_MAP *	timer_map
	)			`[virtual]`

This function fills the IDs (names) of tasks, channels and timers to the parameter lists.

The function is used to generate output for model checkers.

Parameters:

	task_map	stores the Task pointers.
	channel_map	stores the Channel pointers.
	timer_map	stores the Timer pointers.

Reimplemented from DREAM::Node.

Definition at line 1146 of file Task.cpp.

void DREAM::Channel::visitor_uppaal	(	DREAM::NODE_MAP *	task_map,
		DREAM::NODE_MAP *	channel_map,
		DREAM::NODE_MAP *	timer_map,
		std::ofstream &	f_stream
	)			`[virtual]`

This function is part of the Uppaal system description generator.

Parameters:

	task_map	stores the Task pointers.
	channel_map	stores the Channel pointers.
	timer_map	stores the Timer pointers.
	f_stream	is the output stream to be written to.