1/* Copyright (C) 2007 Free Software Foundation, Inc. 2 Contributed by Danny Smith <dannysmith@users.sourceforge.net> 3 4 This file is part of the GNU OpenMP Library (libgomp). 5 6 Libgomp is free software; you can redistribute it and/or modify it 7 under the terms of the GNU Lesser General Public License as published by 8 the Free Software Foundation; either version 2.1 of the License, or 9 (at your option) any later version. 10 11 Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY 12 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 13 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for 14 more details. 15 16 You should have received a copy of the GNU Lesser General Public License 17 along with libgomp; see the file COPYING.LIB. If not, write to the 18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, 19 MA 02110-1301, USA. */ 20 21/* As a special exception, if you link this library with other files, some 22 of which are compiled with GCC, to produce an executable, this library 23 does not by itself cause the resulting executable to be covered by the 24 GNU General Public License. This exception does not however invalidate 25 any other reasons why the executable file might be covered by the GNU 26 General Public License. */ 27 28/* This file contains system specific routines related to counting 29 online processors and dynamic load balancing. It is expected that 30 a system may well want to write special versions of each of these. 31 32 The following implementation uses win32 API routines. */ 33 34#include "libgomp.h" 35#include <windows.h> 36 37/* Count the CPU's currently available to this process. */ 38static int 39count_avail_process_cpus () 40{ 41 DWORD_PTR process_cpus; 42 DWORD_PTR system_cpus; 43 44 if (GetProcessAffinityMask (GetCurrentProcess (), 45 &process_cpus, &system_cpus)) 46 { 47 unsigned int count; 48 for (count = 0; process_cpus != 0; process_cpus >>= 1) 49 if (process_cpus & 1) 50 count++; 51 return count; 52 } 53 return 1; 54} 55 56/* At startup, determine the default number of threads. It would seem 57 this should be related to the number of cpus available to the process. */ 58 59void 60gomp_init_num_threads (void) 61{ 62 gomp_nthreads_var = count_avail_process_cpus (); 63} 64 65/* When OMP_DYNAMIC is set, at thread launch determine the number of 66 threads we should spawn for this team. FIXME: How do we adjust for 67 load average on MS Windows? */ 68 69unsigned 70gomp_dynamic_max_threads (void) 71{ 72 int n_onln = count_avail_process_cpus (); 73 return n_onln > gomp_nthreads_var ? gomp_nthreads_var : n_onln; 74} 75 76int 77omp_get_num_procs (void) 78{ 79 return count_avail_process_cpus (); 80} 81 82ialias (omp_get_num_procs) 83