| /* Copyright (C) 2007-2020 Free Software Foundation, Inc. |
| Contributed by Danny Smith <dannysmith@users.sourceforge.net> |
| |
| This file is part of the GNU Offloading and Multi Processing Library |
| (libgomp). |
| |
| Libgomp is free software; you can redistribute it and/or modify it |
| under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3, or (at your option) |
| any later version. |
| |
| Libgomp 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. |
| |
| Under Section 7 of GPL version 3, you are granted additional |
| permissions described in the GCC Runtime Library Exception, version |
| 3.1, as published by the Free Software Foundation. |
| |
| You should have received a copy of the GNU General Public License and |
| a copy of the GCC Runtime Library Exception along with this program; |
| see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| /* This file contains system specific routines related to counting |
| online processors and dynamic load balancing. It is expected that |
| a system may well want to write special versions of each of these. |
| |
| The following implementation uses win32 API routines. */ |
| |
| #include "libgomp.h" |
| #include <windows.h> |
| |
| /* Count the CPU's currently available to this process. */ |
| static unsigned int |
| count_avail_process_cpus () |
| { |
| DWORD_PTR process_cpus; |
| DWORD_PTR system_cpus; |
| |
| if (GetProcessAffinityMask (GetCurrentProcess (), |
| &process_cpus, &system_cpus)) |
| { |
| unsigned int count; |
| for (count = 0; process_cpus != 0; process_cpus >>= 1) |
| if (process_cpus & 1) |
| count++; |
| return count; |
| } |
| return 1; |
| } |
| |
| /* At startup, determine the default number of threads. It would seem |
| this should be related to the number of cpus available to the process. */ |
| |
| void |
| gomp_init_num_threads (void) |
| { |
| gomp_global_icv.nthreads_var = count_avail_process_cpus (); |
| } |
| |
| /* When OMP_DYNAMIC is set, at thread launch determine the number of |
| threads we should spawn for this team. FIXME: How do we adjust for |
| load average on MS Windows? */ |
| |
| unsigned |
| gomp_dynamic_max_threads (void) |
| { |
| unsigned int n_onln = count_avail_process_cpus (); |
| unsigned int nthreads_var = gomp_icv (false)->nthreads_var; |
| return n_onln > nthreads_var ? nthreads_var : n_onln; |
| } |
| |
| int |
| omp_get_num_procs (void) |
| { |
| return count_avail_process_cpus (); |
| } |
| |
| ialias (omp_get_num_procs) |