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Diffstat (limited to 'libgomp/config/linux/affinity.c')
-rw-r--r-- | libgomp/config/linux/affinity.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/libgomp/config/linux/affinity.c b/libgomp/config/linux/affinity.c new file mode 100644 index 000000000..da9f3d8fd --- /dev/null +++ b/libgomp/config/linux/affinity.c @@ -0,0 +1,103 @@ +/* Copyright (C) 2006, 2007, 2008, 2009, 2010 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 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 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; + +void +gomp_init_affinity (void) +{ + cpu_set_t cpuset, cpusetnew; + size_t idx, widx; + unsigned long cpus = 0; + + 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; + } + + CPU_ZERO (&cpusetnew); + for (widx = idx = 0; idx < gomp_cpu_affinity_len; idx++) + if (gomp_cpu_affinity[idx] < CPU_SETSIZE + && CPU_ISSET (gomp_cpu_affinity[idx], &cpuset)) + { + if (! CPU_ISSET (gomp_cpu_affinity[idx], &cpusetnew)) + { + cpus++; + CPU_SET (gomp_cpu_affinity[idx], &cpusetnew); + } + 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; + if (cpus < gomp_available_cpus) + gomp_available_cpus = cpus; + CPU_ZERO (&cpuset); + CPU_SET (gomp_cpu_affinity[0], &cpuset); + pthread_setaffinity_np (pthread_self (), sizeof (cpuset), &cpuset); + affinity_counter = 1; +} + +void +gomp_init_thread_affinity (pthread_attr_t *attr) +{ + unsigned int cpu; + cpu_set_t cpuset; + + cpu = __sync_fetch_and_add (&affinity_counter, 1); + 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 |