ThreadManager Class Reference

thread manager More...

Public Member Functions
void	init (int numThreads, bool useInteractive, bool useSeed, unsigned int seed)
	Initializes the thread manager. More...
void	startThread (int id, string property)
	Starts a thread. More...
bool	finishThread ()
	Mark the currently running thread as finished. More...
void	invokeScheduler (int location=-1)
	Invokes the scheduler. More...
void	markWaitingOnLock (int id, string name)
	Marks the thread as waiting on the specified lock. More...
void	markWaitingOnSem (int id, string name)
	Marks the thread as waiting on the specified semaphore. More...
int	wakeupThread (deque< int > &waiting)
	Selects a thread to wakeup from the specified waiting queue. More...
void	updateSection (string section)
	Updates the section of the currently running thread. More...
int	getCurrThreadId () const
	Returns the currently running thread. More...
string	getThreadProperty (int id) const
	Returns the property string of the specified thread. More...
string	getThreadTable () const
	Returns a table of all threads in a string. More...

Detailed Description

The thread manager is responsible for managing and scheduling the threads. Initially, the thread manager is initialized using init and each thread must call startThread to indicate they are starting the section of the program where MDAT takes control of the scheduling.

The thread manager contains the scheduler which is invoked using invokeScheduler. If interactive mode is used, the user will be prompted to enter the next thread to run. If random mode is used, the next thread is selected randomly. In either case, only threads that are eligible to run can be selected. Threads that are waiting or already selected cannot be run. If there is a case where no thread can run (and not all threads are completed), the program will abort with a deadlock.

The thread manager provides an interface to the lock and semaphore managers. These managers can mark a thread as waiting using the markWaitingOnLock or markWaitingOnSem methods. The wakeupThread method is also used by the lock and semaphore managers to permit the thread manager to wakeup a thread.

Member Function Documentation

void ThreadManager::init	(	int	numThreads,
		bool	useInteractive,
		bool	useSeed,
		unsigned int	seed
	)

Initializes the thread manager.

Parameters

[in]	numThreads	number of threads to track
[in]	useInteractive	true: use interactive scheduling, false: use random scheduling
[in]	useSeed	true: use specified seed, false: generate random seed based on time of day (ignored if useInteractive is true)
[in]	seed	random seed (ignored if useInteractive is true or useSeed is false)

void ThreadManager::startThread	(	int	id,
		string	property
	)

First waits until all threads have been added. If the thread is the first one to run, it is set to run. Otherwise, the thread is paused.

Parameters

[in]	id	id of thread
[in]	property	property or type of thread

bool ThreadManager::finishThread

(

)

Mark the currently running thread as completed. Returns true if it is last thread to finish and returns false otherwise.

void ThreadManager::invokeScheduler

(

int

location = -1)

Invokes the scheduler, possibly causing a new thread to run. Aborts with a deadlock error if no threads are able to run.

Parameters

[in]

location

location within source code - the currently running thread is updated with this location if the location is nonnegative (>= 0)

void ThreadManager::markWaitingOnLock	(	int	id,
		string	name
	)

Marks the thread as waiting on the specified lock.

Parameters

[in]	id	id of thread to wait
[in]	name	name of lock the thread is waiting on

void ThreadManager::markWaitingOnSem	(	int	id,
		string	name
	)

Marks the thread as waiting on the specified semaphore.

Parameters

[in]	id	id of thread to wait
[in]	name	name of semaphore the thread is waiting on

int ThreadManager::wakeupThread

(

deque< int > &

waiting)

Selects a thread to wakeup from the specified waiting queue. The thread is removed from the waiting queue and placed on the ready queue. The method for selecting the thread is either done by the user (interactive scheduling) or randomly (random scheduling). Note this function does not change the thread that is currently running.

Parameters

[in]

waiting

queue of ids that can wakeup (must not be empty).

void ThreadManager::updateSection

(

string

section)

Updates the section of the currently running thread.

Parameters

[in]

section

name of new section

int ThreadManager::getCurrThreadId

(

)

const

Returns the id of the currently running thread.

string ThreadManager::getThreadProperty

(

int

id)

const

Returns the property string associated with the specified thread.

string ThreadManager::getThreadTable

(

)

const

Returns a table of all threads in a trace-friendly string.