root/orte/test/mpi/binding.c

DEFINITIONS

1. main

   1 /* -*- C -*-
   2  *
   3  * $HEADER$
   4  *
   5  * The most basic of MPI applications
   6  */
   7 
   8 #define _GNU_SOURCE
   9 #include <stdio.h>
  10 #include <sys/types.h>
  11 #include <unistd.h>
  12 #include <sched.h>
  13 #include "opal/mca/hwloc/base/base.h"
  14 #include "mpi.h"
  15 
  16 #include "orte/util/proc_info.h"
  17 
  18 int main(int argc, char* argv[])
  19 {
  20     int rank, size, rc;
  21     hwloc_cpuset_t cpus;
  22     char *bindings = NULL;
  23     cpu_set_t *mask;
  24     int nrcpus, c;
  25     size_t csize;
  26     char hostname[1024];
  27 
  28     MPI_Init(&argc, &argv);
  29     MPI_Comm_rank(MPI_COMM_WORLD, &rank);
  30     MPI_Comm_size(MPI_COMM_WORLD, &size);
  31 
  32     gethostname(hostname, 1024);
  33 
  34     if (OPAL_SUCCESS == opal_hwloc_base_get_topology()) {
  35         cpus = hwloc_bitmap_alloc();
  36         rc = hwloc_get_cpubind(opal_hwloc_topology, cpus, HWLOC_CPUBIND_PROCESS);
  37         hwloc_bitmap_list_asprintf(&bindings, cpus);
  38     }
  39 
  40     printf("[%s;%d] Hello, World, I am %d of %d [%d local peers]: get_cpubind: %d bitmap %s\n",
  41            hostname, (int)getpid(), rank, size, orte_process_info.num_local_peers, rc,
  42            (NULL == bindings) ? "NULL" : bindings);
  43 
  44     nrcpus = sysconf(_SC_NPROCESSORS_ONLN);
  45     mask = CPU_ALLOC(nrcpus);
  46     csize = CPU_ALLOC_SIZE(nrcpus);
  47     CPU_ZERO_S(csize, mask);
  48     if ( sched_getaffinity(0, csize, mask) == -1 ) {
  49         perror("sched_getaffinity");
  50     } else {
  51         for ( c = 0; c < nrcpus; c++ ) {
  52                 if ( CPU_ISSET_S(c, csize, mask) ) {
  53                         printf("[%s:%d] CPU %d is set\n", hostname, (int)getpid(), c);
  54                 }
  55         }
  56     }
  57 
  58     CPU_FREE(mask);
  59 
  60     MPI_Finalize();
  61     return 0;
  62 }