Threads::Task< RT > Class Template Reference

#include <deal.II/base/thread_management.h>

Public Member Functions
	Task (const std_cxx11::function< RT()> &function_object)
	Task (const Task< RT > &t)
	Task ()
void	join () const
bool	joinable () const
RT	return_value ()
bool	operator== (const Task &t) const

Static Public Member Functions
static ::ExceptionBase &	ExcNoTask ()

Private Attributes
std_cxx11::shared_ptr< internal::TaskDescriptor< RT > >	task_descriptor

Detailed Description

template<typename RT = void>
class Threads::Task< RT >

Describes one task object based on the Threading Building Blocks' Task. Note that the call to join() must be executed on the same thread as the call to the constructor. Otherwise, there might be a deadlock. In other words, a Task object should never passed on to another task for calling the join() method.

Author

Wolfgang Bangerth, 2009

Definition at line 2753 of file thread_management.h.

Constructor & Destructor Documentation

Task() [1/3]

template<typename RT = void>

Threads::Task< RT >::Task ( const std_cxx11::function< RT()> &  function_object )

inline

Construct a task object given a function object to execute on the task, and then schedule this function for execution.

Postcondition

Using this constructor automatically makes the task object joinable().

Definition at line 3081 of file thread_management.h.

Task() [2/3]

template<typename RT = void>

Threads::Task< RT >::Task ( const Task< RT > &  t )

inline

Copy constructor.

Postcondition

Using this constructor automatically makes the task object joinable().

Definition at line 3096 of file thread_management.h.

Task() [3/3]

template<typename RT = void>

Threads::Task< RT >::Task ( )

inline

Default constructor. You can't do much with a task object constructed this way, except for assigning it a task object that holds data created by the Threads::new_task() functions.

Postcondition

Using this constructor leaves the object in an unjoinable state, i.e., joinable() will return false.

Definition at line 3110 of file thread_management.h.

Member Function Documentation

join()

template<typename RT = void>

void Threads::Task< RT >::join ( ) const

inline

Join the task represented by this object, i.e. wait for it to finish.

A task can be joined multiple times (while the first join() operation may block until the task has completed running, all successive attempts to join will return immediately).

Precondition

You can't call this function if you have used the default constructor of this class and have not assigned a task object to it. In other words, the function joinable() must return true.

Definition at line 3123 of file thread_management.h.

joinable()

template<typename RT = void>

bool Threads::Task< RT >::joinable ( ) const

inline

Return whether the current object can be joined. You can join a task object once a task (typically created with Threads::new_task()) has actually been assigned to it. On the other hand, the function returns false if the object has been default constructed.

A task can be joined multiple times (while the first join() operation may block until the task has completed running, all successive attempts to join will return immediately). Consequently, if this function returns true, it will continue to return true until the task object it reports on is assigned to from another object.

Definition at line 3141 of file thread_management.h.

return_value()

template<typename RT = void>

RT Threads::Task< RT >::return_value ( )

inline

Get the return value of the function of the task. Since this is only available once the task finishes, this implicitly also calls join(). You can call this function multiple times as long as the object refers to the same task, and expect to get the same return value every time.

Precondition

You can't call this function if you have used the default constructor of this class and have not assigned a task object to it. In other words, the function joinable() must return true.

Definition at line 3158 of file thread_management.h.

operator==()

template<typename RT = void>

bool Threads::Task< RT >::operator== ( const Task< RT > &  t ) const

inline

Check for equality of task objects. Since objects of this class store an implicit pointer to an object that exists exactly once for each task, the check is simply to compare these pointers.

Definition at line 3170 of file thread_management.h.

Member Data Documentation

task_descriptor

template<typename RT = void>

std_cxx11::shared_ptr<internal::TaskDescriptor<RT> > Threads::Task< RT >::task_descriptor

private

Shared pointer to the object representing the task. Boost's shared pointer implementation will make sure that that object lives as long as there is at least one subscriber to it.

Definition at line 3195 of file thread_management.h.

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

• deal.II/base/thread_management.h