Commit 7127a406 authored by Alvarez, Gonzalo's avatar Alvarez, Gonzalo
Browse files

Parallelizer2::parallelFor(start, end, lambda)

parent 7514526c

drivers/testParallelizer2.cpp

+3 −4
Original line number Diff line number Diff line
@@ -12,11 +12,10 @@ int main(int argc, char** argv) 


	PsimagLite::Parallizer2<> parallelizer(threads);



	parallelizer.parallelFor([&v](SizeType i, SizeType)

	parallelizer.parallelFor(0, n, [&v](SizeType i, SizeType)

	{

		v[i] = i + 42;        // <<<--- body of the loop

	},

	n);                       // <<<---- total of the loop

		v[i] = i + 42; 

	});



	/*

	for (SizeType i = 0; i < n; ++i) {

src/Parallelizer2Pthread.h

+19 −16
Original line number Diff line number Diff line
@@ -28,14 +28,15 @@ template<typename SomeLambdaType, 
         >

struct PthreadFunctionStruct {

	PthreadFunctionStruct()

	    : pfh(0),loadBalancer(0),threadNum(0),nthreads(0),total(0),cpu(0)

	    : pfh(0),loadBalancer(0),threadNum(0),nthreads(0),start(0),end(0),cpu(0)

	{}



	const SomeLambdaType* pfh;

	const LoadBalancerType* loadBalancer;

	int threadNum;

	SizeType nthreads;

	SizeType total;

	SizeType start;

	SizeType end;

	SizeType cpu;

};
@@ -57,8 +58,8 @@ void *thread_function_wrapper(void *dummyPtr) 


	for (SizeType p = 0; p < blockSize; ++p) {

		SizeType taskNumber = pfs->loadBalancer->taskNumber(pfs->threadNum, p);

		if (taskNumber > pfs->total) break;

		(*pfh)(taskNumber, pfs->threadNum);

		if (taskNumber + pfs->start >= pfs->end) break;

		(*pfh)(taskNumber + pfs->start, pfs->threadNum);

	}



	return 0;
@@ -78,29 +79,30 @@ public: 


	// no weights, no balancer ==> create weights, set all weigths to 1, delegate

	template<typename SomeLambdaType>

	void parallelFor(const SomeLambdaType& lambda,

	                 SizeType ntasks)

	void parallelFor(SizeType start, SizeType end, const SomeLambdaType& lambda)

	{

		VectorSizeType weights(ntasks,1);

		parallelFor(lambda, weights, ntasks);

		VectorSizeType weights(end - start, 1);

		parallelFor(start, end, lambda, weights);

	}



	// weights, no balancer ==> create balancer with weights ==> delegate

	template<typename SomeLambdaType>

	void parallelFor(const SomeLambdaType& lambda,

	                 const VectorSizeType& weights,

	                 SizeType ntasks)

	void parallelFor(SizeType start,

	                 SizeType end,

	                 const SomeLambdaType& lambda,

	                 const VectorSizeType& weights)

	{

		LoadBalancerType* loadBalancer = new LoadBalancerType(weights, nthreads_);

		parallelFor(lambda, *loadBalancer, ntasks);

		parallelFor(start, end, lambda, *loadBalancer);

		delete loadBalancer;

		loadBalancer = 0;

	}



	template<typename SomeLambdaType>

	void parallelFor(const SomeLambdaType& lambda,

	                 const LoadBalancerType& loadBalancer,

	                 SizeType ntasks)

	void parallelFor(SizeType start,

	                 SizeType end,

	                 const SomeLambdaType& lambda,

	                 const LoadBalancerType& loadBalancer)

	{

		PthreadFunctionStruct<SomeLambdaType>* pfs =

		new PthreadFunctionStruct<SomeLambdaType>[nthreads_];
@@ -111,7 +113,8 @@ public: 
			pfs[j].pfh = &lambda;

			pfs[j].loadBalancer = &loadBalancer;

			pfs[j].threadNum = j;

			pfs[j].total = ntasks;

			pfs[j].start = start;

			pfs[j].end = end;

			pfs[j].nthreads = nthreads_;



			attr[j] = new pthread_attr_t;

src/Parallelizer2Serial.h

+2 −2
Original line number Diff line number Diff line
@@ -16,9 +16,9 @@ public: 
	}



	template<typename SomeLambdaType>

	void parallelFor(const SomeLambdaType& lambda, SizeType n)

	void parallelFor(SizeType start, SizeType end, const SomeLambdaType& lambda)

	{

		for (SizeType i = 0; i < n; ++i)

		for (SizeType i = start; i < end; ++i)

			lambda(i, 0);

	}

};