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<code c++ map.cpp> /* -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */ /* * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * As a special exception, you may use this file as part of a free software * library without restriction. Specifically, if other files instantiate * templates or use macros or inline functions from this file, or you compile * this file and link it with other files to produce an executable, this * file does not by itself cause the resulting executable to be covered by * the GNU General Public License. This exception does not however * invalidate any other reasons why the executable file might be covered by * the GNU General Public License. * ** */

/* * The program is a simple map used: * 1. as a software accelerator (mapSA) * 2. to compute just one single task (mapOneShot). * */ #include <vector> #include <iostream> #include <ff/map.hpp> #include <ff/utils.hpp>

using namespace ff;

this is the map function void* mapF(basePartitioner*const P, int tid) { LinearPartitioner<int>* const partitioner=(LinearPartitioner<int>* const)P; LinearPartitioner<int>::partition_t Partition; partitioner→getPartition(tid, Partition); int* p = (int*)Partition.getData(); gets the pointer to the first element of the partion

  size_t l = Partition.getLength(); // gets the length of the partion

  for(size_t i=0;i<l;++i)  p[i] += tid;

  return p;  // returns the partition pointer !!!

}

long f(long v) { return v+1;}

int main(int argc, char * argv[]) {

  
  if (argc<3) {
      std::cerr << "use: " 
                << argv[0] 
                << " arraysize nworkers\n";
      return -1;
  }
  int arraySize= atoi(argv[1]);
  int nworkers = atoi(argv[2]);

  if (nworkers<=0) {
      std::cerr << "Wrong parameters values\n";
      return -1;
  }
  
  // defining a linear partitioner of integer elements
  LinearPartitioner<int> P(arraySize,nworkers);
  // defining the map passing as parameter the function called 
  // within each worker and the partitioner that has to be used
  // to create the worker partitions
  ff_map mapSA(mapF,&P, NULL, true); // the 4rd parameter enable the accelerator mode
  mapSA.run();

  printf("\nmapSA:\n");
  for(int i=0;i<10;++i) {
      // create a task
      int* A=new int[arraySize];
      for(int j=0;j<arraySize;++j) A[j]=i;

      // offload the task into the map 
      mapSA.offload(A);

      // wait for the result (NOTE: also the non-blocking call may be used !)
      void* R=NULL;
      mapSA.load_result(&R);

      // print the result
      for(int j=0;j<arraySize;++j) printf("%d ", ((int*)R)[j]);
      printf("\n");
  }
  // stopping the accelerator
  mapSA.offload(EOS);
  mapSA.wait();

  long *oneTask=new long[arraySize];

  for(long j=0;j<arraySize;++j) oneTask[j]=j;
  FF_MAP(map, oneTask,arraySize, f, nworkers);

#if 0

  ff_map mapOneShot(mapF,&P, oneTask);
  mapOneShot.run_and_wait_end();

#endif

  //ff_map mapOneShot(mapF,&P, oneTask);
  //mapOneShot.run_and_wait_end();
  // print the result
  printf("\nmapOneShot:\n");
  for(int j=0;j<arraySize;++j) printf("%ld ", oneTask[j]);
  printf("\n");

  std::cerr << "DONE\n";
  return 0;

} <code>