| /* Copyright (C) 2006, 2007 Free Software Foundation, Inc. |
| Contributed by Jakub Jelinek <jakub@redhat.com>. |
| |
| This file is part of the GNU OpenMP Library (libgomp). |
| |
| Libgomp is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 2.1 of the License, 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 Lesser General Public License for |
| more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with libgomp; see the file COPYING.LIB. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, |
| MA 02110-1301, USA. */ |
| |
| /* As a special exception, if you link this library with other files, some |
| of which are compiled with GCC, to produce an executable, this library |
| 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. */ |
| |
| /* This is a Linux specific implementation of a CPU affinity setting. */ |
| |
| #ifndef _GNU_SOURCE |
| #define _GNU_SOURCE 1 |
| #endif |
| #include "libgomp.h" |
| #include <sched.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| |
| #ifdef HAVE_PTHREAD_AFFINITY_NP |
| |
| static unsigned int affinity_counter; |
| #ifndef HAVE_SYNC_BUILTINS |
| static gomp_mutex_t affinity_lock; |
| #endif |
| |
| void |
| gomp_init_affinity (void) |
| { |
| cpu_set_t cpuset; |
| size_t idx, widx; |
| |
| if (pthread_getaffinity_np (pthread_self (), sizeof (cpuset), &cpuset)) |
| { |
| gomp_error ("could not get CPU affinity set"); |
| free (gomp_cpu_affinity); |
| gomp_cpu_affinity = NULL; |
| gomp_cpu_affinity_len = 0; |
| return; |
| } |
| |
| for (widx = idx = 0; idx < gomp_cpu_affinity_len; idx++) |
| if (gomp_cpu_affinity[idx] < CPU_SETSIZE |
| && CPU_ISSET (gomp_cpu_affinity[idx], &cpuset)) |
| gomp_cpu_affinity[widx++] = gomp_cpu_affinity[idx]; |
| |
| if (widx == 0) |
| { |
| gomp_error ("no CPUs left for affinity setting"); |
| free (gomp_cpu_affinity); |
| gomp_cpu_affinity = NULL; |
| gomp_cpu_affinity_len = 0; |
| return; |
| } |
| |
| gomp_cpu_affinity_len = widx; |
| CPU_ZERO (&cpuset); |
| CPU_SET (gomp_cpu_affinity[0], &cpuset); |
| pthread_setaffinity_np (pthread_self (), sizeof (cpuset), &cpuset); |
| affinity_counter = 1; |
| #ifndef HAVE_SYNC_BUILTINS |
| gomp_mutex_init (&affinity_lock); |
| #endif |
| } |
| |
| void |
| gomp_init_thread_affinity (pthread_attr_t *attr) |
| { |
| unsigned int cpu; |
| cpu_set_t cpuset; |
| |
| #ifdef HAVE_SYNC_BUILTINS |
| cpu = __sync_fetch_and_add (&affinity_counter, 1); |
| #else |
| gomp_mutex_lock (&affinity_lock); |
| cpu = affinity_counter++; |
| gomp_mutex_unlock (&affinity_lock); |
| #endif |
| cpu %= gomp_cpu_affinity_len; |
| CPU_ZERO (&cpuset); |
| CPU_SET (gomp_cpu_affinity[cpu], &cpuset); |
| pthread_attr_setaffinity_np (attr, sizeof (cpu_set_t), &cpuset); |
| } |
| |
| #else |
| |
| #include "../posix/affinity.c" |
| |
| #endif |