Nektar::Thread::ThreadManagerStd Class Reference

Implementation of ThreadManager using std::thread. More...

#include <ThreadStd.h>

Inheritance diagram for Nektar::Thread::ThreadManagerStd:

Classes
class	Barrier
	Lightweight barrier class. More...

Public Member Functions
	ThreadManagerStd (unsigned int numWorkers)
	Constructs a ThreadManagerStd. More...
	~ThreadManagerStd () override
	Shuts down threading. More...
Public Member Functions inherited from Nektar::Thread::ThreadManager
virtual	~ThreadManager ()
	Destructor. More...
void	QueueJobs (std::vector< ThreadJob * > &joblist)
	Pass a list of tasklets to the master queue. More...
void	QueueJob (ThreadJob *job)
	Pass a single job to the master queue. More...
unsigned int	GetNumWorkers ()
	Return the number of active workers. More...
unsigned int	GetWorkerNum ()
	Returns the worker number of the executing thread. More...
void	SetNumWorkers (const unsigned int num)
	Sets the number of active workers. More...
void	SetNumWorkers ()
	Sets the number of active workers to the maximum. More...
unsigned int	GetMaxNumWorkers ()
	Gets the maximum available number of threads. More...
void	Wait ()
	Waits until all queued jobs are finished. More...
void	SetChunkSize (unsigned int chnk)
	Controls how many jobs are sent to each worker at a time. More...
void	SetSchedType (SchedType s)
	Sets the current scheduling algorithm. More...
bool	InThread ()
	Indicates whether the code is in a worker thread or not. More...
void	Hold ()
	A calling threads holds until all active threads call this method. More...
const std::string &	GetType ()
	Returns a description of the type of threading. More...
bool	IsInitialised ()
	ThreadManager implementation. More...
int	GetThrFromPartition (int pPartition)
int	GetRankFromPartition (int pPartition)
int	GetPartitionFromRankThr (int pRank, unsigned int pThr)

Static Public Member Functions
static ThreadManagerSharedPtr	Create (unsigned int numT)
	Called by the factory method. More...

Protected Member Functions
void	v_QueueJobs (std::vector< ThreadJob * > &joblist) override
void	v_QueueJob (ThreadJob *job) override
unsigned int	v_GetNumWorkers () override
unsigned int	v_GetWorkerNum () override
void	v_SetNumWorkers (const unsigned int num) override
void	v_SetNumWorkers () override
unsigned int	v_GetMaxNumWorkers () override
void	v_Wait () override
void	v_SetChunkSize (unsigned int chnk) override
void	v_SetSchedType (SchedType s) override
bool	v_InThread () override
void	v_Hold () override
const std::string &	v_GetType () const override
Protected Member Functions inherited from Nektar::Thread::ThreadManager
virtual void	v_QueueJobs (std::vector< ThreadJob * > &joblist)=0
virtual void	v_QueueJob (ThreadJob *job)=0
virtual unsigned int	v_GetNumWorkers ()=0
virtual unsigned int	v_GetWorkerNum ()=0
virtual void	v_SetNumWorkers (const unsigned int num)=0
virtual void	v_SetNumWorkers ()=0
virtual unsigned int	v_GetMaxNumWorkers ()=0
virtual void	v_Wait ()=0
virtual void	v_SetChunkSize (unsigned int chnk)=0
virtual void	v_SetSchedType (SchedType s)=0
virtual bool	v_InThread ()=0
virtual void	v_Hold ()=0
virtual const std::string &	v_GetType () const =0
virtual bool	v_IsInitialised ()

Private Member Functions
	ThreadManagerStd ()
	ThreadManagerStd (const ThreadManagerStd &)
bool	IsWorking ()
void	SetNumWorkersImpl (const unsigned int num)

Private Attributes
const unsigned int	m_numThreads
unsigned int	m_numWorkers
std::queue< ThreadJob * >	m_masterQueue
std::mutex	m_masterQueueMutex
std::mutex	m_masterActiveMutex
std::condition_variable	m_masterQueueCondVar
std::condition_variable	m_masterActiveCondVar
ThreadWorkerStd **	m_threadList
std::thread **	m_threadThreadList
std::thread::id	m_masterThreadId
bool *	m_threadBusyList
bool *	m_threadActiveList
unsigned int	m_chunkSize
SchedType	m_schedType
Barrier *	m_barrier
std::map< std::thread::id, unsigned int >	m_threadMap
std::string	m_type

Static Private Attributes
static std::string	className

Friends
class	ThreadWorkerStd

Detailed Description

Implementation of ThreadManager using std::thread.

Definition at line 57 of file ThreadStd.h.

Constructor & Destructor Documentation

ThreadManagerStd() [1/3]

Nektar::Thread::ThreadManagerStd::ThreadManagerStd

(

unsigned int

numT

)

Constructs a ThreadManagerStd.

Parameters

numWorkers

The number of threads to start (including master thread).

Note

Do not use, use factory instead.

Definition at line 54 of file ThreadStd.cpp.

    : m_numThreads(numT), m_numWorkers(numT), m_masterQueue(),
      m_masterQueueMutex(), m_masterActiveMutex(), m_masterQueueCondVar(),
      m_masterActiveCondVar(), m_chunkSize(1), m_schedType(e_dynamic),
      m_threadMap()
{
    using namespace std;
    try
    {
        m_threadList       = new ThreadWorkerStd *[m_numThreads];
        m_threadThreadList = new std::thread *[m_numThreads];
        m_threadBusyList   = new bool[m_numThreads];
        m_threadActiveList = new bool[m_numThreads];
    }
    catch (exception &e)
    {
        cerr << "Exception while allocating thread storage: " << e.what()
             << endl;
        abort();
    }
    unsigned int i = 0;
    while (i < m_numThreads)
    {
        ThreadWorkerStd *tw;
        try
        {
            tw = new ThreadWorkerStd(this, i);
        }
        catch (exception &e)
        {
            cerr << "Exception while allocating worker threads: " << e.what()
                 << endl;
            abort();
        }
 
        m_threadList[i]       = tw;
        m_threadBusyList[i]   = false;
        m_threadActiveList[i] = true;
 
        try
        {
            m_threadThreadList[i] = new std::thread(std::ref(*tw));
            std::thread::id id    = m_threadThreadList[i]->get_id();
            m_threadMap[id]       = i;
        }
        catch (...)
        {
            std::cerr << "Exception while creating worker threads" << std::endl;
            abort();
        }
        i++;
    }
    m_masterThreadId = std::this_thread::get_id();
    m_barrier        = new Barrier(m_numWorkers > 0 ? m_numWorkers : 1);
    m_type           = "Threading with Std";
}

References m_barrier, m_masterThreadId, m_numThreads, m_numWorkers, m_threadActiveList, m_threadBusyList, m_threadList, m_threadMap, m_threadThreadList, m_type, and ThreadWorkerStd.

~ThreadManagerStd()

Nektar::Thread::ThreadManagerStd::~ThreadManagerStd ( )

override

Shuts down threading.

Terminates all running threads (they will finish their current job), releases resources and destructs.

Definition at line 115 of file ThreadStd.cpp.

{
    // This is an immediate teardown.  We attempt to kill everything.
    // we daren't lock anything as we may cause a deadlock
    for (unsigned int i = 0; i < m_numThreads; i++)
    {
        m_threadList[i]->Stop();
    }
 
    m_masterQueueCondVar.notify_all();
    m_masterActiveCondVar.notify_all();
    for (unsigned int i = 0; i < m_numThreads; i++)
    {
        m_threadThreadList[i]->join();
        delete m_threadThreadList[i];
        delete m_threadList[i];
    }
 
    delete[] m_threadList;
    delete[] m_threadThreadList;
    delete[] m_threadActiveList;
    delete[] m_threadBusyList;
    delete m_barrier;
}

References m_barrier, m_masterActiveCondVar, m_masterQueueCondVar, m_numThreads, m_threadActiveList, m_threadBusyList, m_threadList, m_threadThreadList, and Nektar::Thread::ThreadWorkerStd::Stop().

ThreadManagerStd() [2/3]

Nektar::Thread::ThreadManagerStd::ThreadManagerStd ( )

private

Referenced by Create().

ThreadManagerStd() [3/3]

Nektar::Thread::ThreadManagerStd::ThreadManagerStd ( const ThreadManagerStd &  )

private

Member Function Documentation

Create()

static ThreadManagerSharedPtr Nektar::Thread::ThreadManagerStd::Create ( unsigned int  numT )

inlinestatic

Called by the factory method.

Definition at line 104 of file ThreadStd.h.

    {
        return std::shared_ptr<ThreadManager>(new ThreadManagerStd(numT));
    }

References ThreadManagerStd().

IsWorking()

bool Nektar::Thread::ThreadManagerStd::IsWorking ( )

private

Definition at line 165 of file ThreadStd.cpp.

{
    bool working = false;
    Lock masterActiveLock(m_masterActiveMutex);
    for (unsigned int i = 0; i < m_numWorkers; i++)
    {
        working = working || m_threadBusyList[i];
    }
    return working;
}

References m_masterActiveMutex, m_numWorkers, and m_threadBusyList.

Referenced by v_Wait().

SetNumWorkersImpl()

void Nektar::Thread::ThreadManagerStd::SetNumWorkersImpl ( const unsigned int  num )

private

Definition at line 242 of file ThreadStd.cpp.

{
    Lock masterActiveLock(m_masterActiveMutex); // locks the active
 
    if (m_numWorkers == num)
    {
        return;
    }
 
    delete m_barrier;
    m_barrier = new Barrier(num > 0 ? num : 1);
 
    m_numWorkers = num;
    for (unsigned int i = 0; i < m_numThreads; i++)
    {
        m_threadActiveList[i] = i < m_numWorkers ? true : false;
    }
    m_masterActiveCondVar.notify_all();
} // Lock on active released here

References m_barrier, m_masterActiveCondVar, m_masterActiveMutex, m_numThreads, m_numWorkers, and m_threadActiveList.

Referenced by v_SetNumWorkers().

v_GetMaxNumWorkers()

unsigned int Nektar::Thread::ThreadManagerStd::v_GetMaxNumWorkers ( )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 284 of file ThreadStd.cpp.

{
    return m_numThreads;
}

References m_numThreads.

v_GetNumWorkers()

unsigned int Nektar::Thread::ThreadManagerStd::v_GetNumWorkers ( )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 225 of file ThreadStd.cpp.

{
    return m_numWorkers;
}

References m_numWorkers.

v_GetType()

const std::string & Nektar::Thread::ThreadManagerStd::v_GetType ( ) const

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 300 of file ThreadStd.cpp.

{
    return m_type;
}

References m_type.

v_GetWorkerNum()

unsigned int Nektar::Thread::ThreadManagerStd::v_GetWorkerNum ( )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 233 of file ThreadStd.cpp.

{
    std::thread::id id = std::this_thread::get_id();
    return m_threadMap[id];
}

References m_threadMap.

v_Hold()

void Nektar::Thread::ThreadManagerStd::v_Hold ( )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 292 of file ThreadStd.cpp.

{
    m_barrier->Wait();
}

References m_barrier, and Nektar::Thread::ThreadManagerStd::Barrier::Wait().

v_InThread()

bool Nektar::Thread::ThreadManagerStd::v_InThread ( )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 197 of file ThreadStd.cpp.

{
    std::thread::id id = std::this_thread::get_id();
    return (id != m_masterThreadId);
}

References m_masterThreadId.

v_QueueJob()

void Nektar::Thread::ThreadManagerStd::v_QueueJob ( ThreadJob *  job )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 155 of file ThreadStd.cpp.

{
    Lock masterQueueLock(m_masterQueueMutex); // locks the queue
    m_masterQueue.push(job);
    m_masterQueueCondVar.notify_all(); // alert a waiting thread.
} // queue unlocked

References m_masterQueue, m_masterQueueCondVar, and m_masterQueueMutex.

v_QueueJobs()

void Nektar::Thread::ThreadManagerStd::v_QueueJobs ( std::vector< ThreadJob * > &  joblist )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 143 of file ThreadStd.cpp.

{
    std::vector<ThreadJob *>::iterator it;
    for (it = joblist.begin(); it < joblist.end(); ++it)
    {
        QueueJob(*it);
    }
}

References Nektar::Thread::ThreadManager::QueueJob().

v_SetChunkSize()

void Nektar::Thread::ThreadManagerStd::v_SetChunkSize ( unsigned int  chnk )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 179 of file ThreadStd.cpp.

{
    Lock masterQueueLock(m_masterQueueMutex); // locks the queue
    m_chunkSize = std::max(chnk, 1U);
}

References m_chunkSize, and m_masterQueueMutex.

v_SetNumWorkers() [1/2]

void Nektar::Thread::ThreadManagerStd::v_SetNumWorkers ( )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 276 of file ThreadStd.cpp.

{
    SetNumWorkersImpl(m_numThreads);
}

References m_numThreads, and SetNumWorkersImpl().

v_SetNumWorkers() [2/2]

void Nektar::Thread::ThreadManagerStd::v_SetNumWorkers ( const unsigned int  num )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 265 of file ThreadStd.cpp.

{
    unsigned int n;
    n = std::min(num, m_numThreads);
    n = std::max(n, static_cast<unsigned int>(0));
    SetNumWorkersImpl(n);
}

References m_numThreads, and SetNumWorkersImpl().

v_SetSchedType()

void Nektar::Thread::ThreadManagerStd::v_SetSchedType ( SchedType  s )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 188 of file ThreadStd.cpp.

{
    Lock masterQueueLock(m_masterQueueMutex); // locks the queue
    m_schedType = s;
}

References m_masterQueueMutex, and m_schedType.

v_Wait()

void Nektar::Thread::ThreadManagerStd::v_Wait ( )

overrideprotectedvirtual

Implements Nektar::Thread::ThreadManager.

Definition at line 206 of file ThreadStd.cpp.

{
    bool working;
    Lock masterQueueLock(m_masterQueueMutex); // locks the queue
    working = IsWorking();
    m_masterActiveCondVar.notify_all();
    m_masterQueueCondVar.notify_all();
    while (!m_masterQueue.empty() || working)
    {
        // while waiting, master queue is unlocked
        m_masterQueueCondVar.wait(masterQueueLock);
        // on exiting wait master queue is locked again
        working = IsWorking();
    }
}

References IsWorking(), m_masterActiveCondVar, m_masterQueue, m_masterQueueCondVar, and m_masterQueueMutex.

Friends And Related Function Documentation

ThreadWorkerStd

friend class ThreadWorkerStd

friend

So the workers can access the master queue and locks.

Definition at line 95 of file ThreadStd.h.

Referenced by ThreadManagerStd().

Member Data Documentation

className

std::string Nektar::Thread::ThreadManagerStd::className

staticprivate

Initial value:

=
    GetThreadManagerFactory().RegisterCreatorFunction(
        "ThreadManagerStd", ThreadManagerStd::Create,
        "Threading using std::thread.")

Definition at line 147 of file ThreadStd.h.

m_barrier

Barrier* Nektar::Thread::ThreadManagerStd::m_barrier

private

Definition at line 145 of file ThreadStd.h.

Referenced by SetNumWorkersImpl(), ThreadManagerStd(), v_Hold(), and ~ThreadManagerStd().

m_chunkSize

unsigned int Nektar::Thread::ThreadManagerStd::m_chunkSize

private

Definition at line 143 of file ThreadStd.h.

Referenced by Nektar::Thread::ThreadWorkerStd::GetNumToLoad(), and v_SetChunkSize().

m_masterActiveCondVar

std::condition_variable Nektar::Thread::ThreadManagerStd::m_masterActiveCondVar

private

Definition at line 137 of file ThreadStd.h.

Referenced by SetNumWorkersImpl(), v_Wait(), Nektar::Thread::ThreadWorkerStd::WaitForActive(), and ~ThreadManagerStd().

m_masterActiveMutex

std::mutex Nektar::Thread::ThreadManagerStd::m_masterActiveMutex

private

Definition at line 135 of file ThreadStd.h.

Referenced by IsWorking(), Nektar::Thread::ThreadWorkerStd::LoadJobs(), SetNumWorkersImpl(), and Nektar::Thread::ThreadWorkerStd::WaitForActive().

m_masterQueue

std::queue<ThreadJob *> Nektar::Thread::ThreadManagerStd::m_masterQueue

private

Definition at line 133 of file ThreadStd.h.

Referenced by Nektar::Thread::ThreadWorkerStd::GetNumToLoad(), Nektar::Thread::ThreadWorkerStd::LoadJobs(), v_QueueJob(), and v_Wait().

m_masterQueueCondVar

std::condition_variable Nektar::Thread::ThreadManagerStd::m_masterQueueCondVar

private

Definition at line 136 of file ThreadStd.h.

Referenced by Nektar::Thread::ThreadWorkerStd::LoadJobs(), v_QueueJob(), v_Wait(), and ~ThreadManagerStd().

m_masterQueueMutex

std::mutex Nektar::Thread::ThreadManagerStd::m_masterQueueMutex

private

Definition at line 134 of file ThreadStd.h.

Referenced by Nektar::Thread::ThreadWorkerStd::LoadJobs(), v_QueueJob(), v_SetChunkSize(), v_SetSchedType(), and v_Wait().

m_masterThreadId

std::thread::id Nektar::Thread::ThreadManagerStd::m_masterThreadId

private

Definition at line 140 of file ThreadStd.h.

Referenced by ThreadManagerStd(), and v_InThread().

m_numThreads

const unsigned int Nektar::Thread::ThreadManagerStd::m_numThreads

private

Definition at line 131 of file ThreadStd.h.

Referenced by SetNumWorkersImpl(), ThreadManagerStd(), v_GetMaxNumWorkers(), v_SetNumWorkers(), and ~ThreadManagerStd().

m_numWorkers

unsigned int Nektar::Thread::ThreadManagerStd::m_numWorkers

private

Definition at line 132 of file ThreadStd.h.

Referenced by Nektar::Thread::ThreadWorkerStd::GetNumToLoad(), IsWorking(), SetNumWorkersImpl(), ThreadManagerStd(), and v_GetNumWorkers().

m_schedType

SchedType Nektar::Thread::ThreadManagerStd::m_schedType

private

Definition at line 144 of file ThreadStd.h.

Referenced by Nektar::Thread::ThreadWorkerStd::GetNumToLoad(), and v_SetSchedType().

m_threadActiveList

bool* Nektar::Thread::ThreadManagerStd::m_threadActiveList

private

Definition at line 142 of file ThreadStd.h.

Referenced by Nektar::Thread::ThreadWorkerStd::LoadJobs(), SetNumWorkersImpl(), ThreadManagerStd(), Nektar::Thread::ThreadWorkerStd::WaitForActive(), and ~ThreadManagerStd().

m_threadBusyList

bool* Nektar::Thread::ThreadManagerStd::m_threadBusyList

private

Definition at line 141 of file ThreadStd.h.

Referenced by IsWorking(), Nektar::Thread::ThreadWorkerStd::LoadJobs(), ThreadManagerStd(), and ~ThreadManagerStd().

m_threadList

ThreadWorkerStd** Nektar::Thread::ThreadManagerStd::m_threadList

private

Definition at line 138 of file ThreadStd.h.

Referenced by ThreadManagerStd(), and ~ThreadManagerStd().

m_threadMap

std::map<std::thread::id, unsigned int> Nektar::Thread::ThreadManagerStd::m_threadMap

private

Definition at line 146 of file ThreadStd.h.

Referenced by ThreadManagerStd(), and v_GetWorkerNum().

m_threadThreadList

std::thread** Nektar::Thread::ThreadManagerStd::m_threadThreadList

private

Definition at line 139 of file ThreadStd.h.

Referenced by ThreadManagerStd(), and ~ThreadManagerStd().

m_type

std::string Nektar::Thread::ThreadManagerStd::m_type

private

Definition at line 148 of file ThreadStd.h.

Referenced by ThreadManagerStd(), and v_GetType().