TBB 学习笔记
#include <tbb/task_scheduler_init.h> #include <tbb/blocked_range.h> #include <tbb/parallel_for.h> #include <iostream> class ApplyFoo { private: float *const my_a; public: void operator()(const tbb::blocked_range<size_t>&r)const { float *a=my_a; for(int i=r.begin();i!=r.end();++i) { printf("gevar = %f\n",a[i]); } } ApplyFoo(float a[]): my_a(a) { } }; void parallelApplyFoo(float a[],size_t n) { tbb::parallel_for ( tbb::blocked_range<size_t> (0,n),ApplyFoo(a) ,tbb::auto_partitioner()); } int main() { //tbb::task_scheduler_init init; float a[10]={1,2,3,4,5,6,7,8,9,10}; parallelApplyFoo(a,10); return 0; }
修改简化版本:
#include <iostream> #include <tbb/task_scheduler_init.h> #include <tbb/blocked_range.h> #include <tbb/parallel_for.h> #include <vector> using namespace std; using namespace tbb; #define THREAD_FUNCTION void operator()(const blocked_range<size_t> &r)const #define THREAD_EXCUTED_FOR(N,CLASS)\ {\ parallel_for(blocked_range<size_t>(0,N),CLASS,auto_partitioner());\ } class ApplyFoo { public: ApplyFoo() { } void setData(float *data) { my_a = data; } THREAD_FUNCTION { //cout << "going to thread\n"; float *a = my_a; for(size_t i=r.begin();i!=r.end();++i) { //cout << "going to thread:"<<i<<endl; a[i] = 10; } } private: float * my_a; }; int main() { long int size = 5000000000; vector<float> b(size); cout << "loop size " << b.size() << endl; cout << "start threading\n"; ApplyFoo foo; foo.setData(b.data()); THREAD_EXCUTED_FOR(size,foo); cout << "thread executed end\n"; cout << b[0] << endl; return 0; }
posted on 2015-07-26 22:44 gearslogy 阅读(1830) 评论(0) 编辑 收藏 举报