git.m6w6.name Git - m6w6/libmemcached/blob - libtest/cpu.cc

   1 /*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
   2  *
   3  *  libtest
   4  *
   5  *  Copyright (C) 2012 Data Differential, http://datadifferential.com/
   6  *
   7  *  This library is free software; you can redistribute it and/or
   8  *  modify it under the terms of the GNU Lesser General Public
   9  *  License as published by the Free Software Foundation; either
  10  *  version 3 of the License, or (at your option) any later version.
  11  *
  12  *  This library is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  *  Lesser General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU Lesser General Public
  18  *  License along with this library; if not, write to the Free Software
  19  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  20  */
  21
  22 #include <libtest/common.h>
  23
  24 #include <unistd.h>
  25
  26 #if defined(HAVE_SYS_SYSCTL_H) && HAVE_SYS_SYSCTL_H
  27 #include <sys/sysctl.h>
  28 #endif
  29
  30 namespace libtest {
  31
  32 size_t number_of_cpus()
  33 {
  34   size_t number_of_cpu= 1;
  35 #if TARGET_OS_LINUX
  36   number_of_cpu= sysconf(_SC_NPROCESSORS_ONLN);
  37 #elif defined(HAVE_SYS_SYSCTL_H) && defined(CTL_HW) && defined(HW_NCPU) && defined(HW_AVAILCPU) && defined(HW_NCPU)
  38   int mib[4];
  39   size_t len= sizeof(number_of_cpu);
  40
  41   /* set the mib for hw.ncpu */
  42   mib[0] = CTL_HW;
  43   mib[1] = HW_AVAILCPU;  // alternatively, try HW_NCPU;
  44
  45   /* get the number of CPUs from the system */
  46   sysctl(mib, 2, &number_of_cpu, &len, NULL, 0);
  47
  48   if (number_of_cpu < 1)
  49   {
  50     mib[1]= HW_NCPU;
  51     sysctl(mib, 2, &number_of_cpu, &len, NULL, 0 );
  52
  53     if (number_of_cpu < 1 )
  54     {
  55       number_of_cpu = 1;
  56     }
  57   }
  58 #else
  59   fprintf(stderr, "Going with guessing\n");
  60 #endif
  61
  62   return number_of_cpu;
  63 }
  64
  65 } // namespace libtest