Nektar::Thread::ThreadMaster Class Reference

#include <Thread.h>

Public Types
enum	ThreadManagerName { SessionJob , THREADMANAGER_MAX }

Public Member Functions
	ThreadMaster ()
	Constructor. More...
	~ThreadMaster ()
	Destructor. More...
void	SetThreadingType (const std::string &p_type)
	Sets what ThreadManagers will be created in CreateInstance. More...
ThreadManagerSharedPtr &	GetInstance (const ThreadManagerName t)
	Gets the ThreadManager associated with string s. More...
ThreadManagerSharedPtr	CreateInstance (const ThreadManagerName t, unsigned int nThr)
	Creates an instance of a ThreadManager (which one is determined by a previous call to SetThreadingType) and associates it with the string s. More...

Private Attributes
std::vector< ThreadManagerSharedPtr >	m_threadManagers
std::shared_mutex	m_mutex
std::string	m_threadingType

Detailed Description

A class to manage multiple ThreadManagers. It also acts as a cut-out during static initialisation, where code attempts to grab a ThreadManager before any can have been initialised. When this happens the ThreadMaster creates a simple implementation of ThreadManager, ThreadStartupManager, which behaves as a single-threaded ThreadManager that fails if anything non-trivial is attempted. This means code should be cautious about caching the value of GetInstance(string), as it might change once that particular threading system is initialised.

Multiple ThreadManagers should now be possible. Each is identified with a string and can be recovered by calling Thread::GetThreadMaster().GetInstance(string).

ThreadMaster is thread-safe apart from CreateInstance. Call CreateInstance in single threaded code only.

Definition at line 396 of file Thread.h.

Member Enumeration Documentation

ThreadManagerName

enum Nektar::Thread::ThreadMaster::ThreadManagerName

Enumerator
SessionJob
THREADMANAGER_MAX

Definition at line 404 of file Thread.h.

    {
        SessionJob,
        THREADMANAGER_MAX
    };

Constructor & Destructor Documentation

ThreadMaster()

Nektar::Thread::ThreadMaster::ThreadMaster

(

)

Constructor.

ThreadMaster implementation

Definition at line 110 of file Thread.cpp.

    : m_threadManagers(THREADMANAGER_MAX), m_mutex(), m_threadingType()
{
    // empty
}

~ThreadMaster()

Nektar::Thread::ThreadMaster::~ThreadMaster

(

)

Destructor.

Will clear the list of ThreadManagers, destructing them.

Definition at line 119 of file Thread.cpp.

{
    // Locking is a bit pointless, since the map is empty after this call.
    m_threadManagers.clear();
}

References m_threadManagers.

Member Function Documentation

CreateInstance()

ThreadManagerSharedPtr Nektar::Thread::ThreadMaster::CreateInstance	(	const ThreadManagerName	t,
		unsigned int	nThr
	)

Creates an instance of a ThreadManager (which one is determined by a previous call to SetThreadingType) and associates it with the string s.

Returns

Shared pointer to the created ThreadManager.

An error occurs if this is called before SetThreadingType.

Definition at line 179 of file Thread.cpp.

{
    ASSERTL0(!m_threadingType.empty(),
             "Trying to create a ThreadManager before SetThreadingType called");
    return m_threadManagers[t] =
               Thread::GetThreadManagerFactory().CreateInstance(m_threadingType,
                                                                nThr);
}

References ASSERTL0, Nektar::LibUtilities::NekFactory< tKey, tBase, tParam >::CreateInstance(), Nektar::Thread::GetThreadManagerFactory(), m_threadingType, and m_threadManagers.

GetInstance()

ThreadManagerSharedPtr & Nektar::Thread::ThreadMaster::GetInstance

(

const ThreadManagerName

t

)

Gets the ThreadManager associated with string s.

Returns

a shared pointer to /em either a ThreadStartupManager or whatever ThreadManager has been created for the string s with CreateInstance.

Calling code may store the result if it is sure the call to GetInstance(s) has occurred after the call to CreateInstance(s). This cannot be before threadedcommReader::StartThreads(), as that's where SetThreadingType is called.

Warning

Static initialisation may want to access a ThreadManager. Such code must be able to cope with the temporary ThreadStartupManager.

Definition at line 163 of file Thread.cpp.

{
    if (!m_threadManagers[t])
    {
        m_threadManagers[t] =
            ThreadManagerSharedPtr(new ThreadStartupManager());
        return m_threadManagers[t];
    }
    return m_threadManagers[t];
}

References m_threadManagers.

SetThreadingType()

void Nektar::Thread::ThreadMaster::SetThreadingType

(

const std::string &

p_type

)

Sets what ThreadManagers will be created in CreateInstance.

Parameters

p_type

String to be passed to the ThreadManagerFactory

Subsequent CreateInstance calls will pass this string to the ThreadManagerFactory to create a ThreadManager.

It is an error to call this more than once (since having different kinds of ThreadManager active is probably a stupendously bad idea).

Definition at line 143 of file Thread.cpp.

{
    ASSERTL0(m_threadingType.empty(),
             "Tried to SetThreadingType when it was already set");
    m_threadingType = p_type;
}

References ASSERTL0, and m_threadingType.

Member Data Documentation

m_mutex

std::shared_mutex Nektar::Thread::ThreadMaster::m_mutex

private

Definition at line 400 of file Thread.h.

m_threadingType

std::string Nektar::Thread::ThreadMaster::m_threadingType

private

Definition at line 401 of file Thread.h.

Referenced by CreateInstance(), and SetThreadingType().

m_threadManagers

std::vector<ThreadManagerSharedPtr> Nektar::Thread::ThreadMaster::m_threadManagers

private

Definition at line 399 of file Thread.h.

Referenced by CreateInstance(), GetInstance(), and ~ThreadMaster().