diff options
Diffstat (limited to 'linuxthreads/sysdeps/unix/sysv/linux/smp.h')
-rw-r--r-- | linuxthreads/sysdeps/unix/sysv/linux/smp.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/linuxthreads/sysdeps/unix/sysv/linux/smp.h b/linuxthreads/sysdeps/unix/sysv/linux/smp.h new file mode 100644 index 0000000000..81289294b4 --- /dev/null +++ b/linuxthreads/sysdeps/unix/sysv/linux/smp.h @@ -0,0 +1,48 @@ +/* Determine whether the host has multiple processors. Linux version. + Copyright (C) 1996, 2002 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <sys/sysctl.h> + +/* Test whether the machine has more than one processor. This is not the + best test but good enough. More complicated tests would require `malloc' + which is not available at that time. */ +static inline int +is_smp_system (void) +{ + static const int sysctl_args[] = { CTL_KERN, KERN_VERSION }; + char buf[512]; + size_t reslen = sizeof (buf); + + /* Try reading the number using `sysctl' first. */ + if (__sysctl ((int *) sysctl_args, + sizeof (sysctl_args) / sizeof (sysctl_args[0]), + buf, &reslen, NULL, 0) < 0) + { + /* This was not successful. Now try reading the /proc filesystem. */ + int fd = __open ("/proc/sys/kernel/version", O_RDONLY); + if (__builtin_expect (fd, 0) == -1 + || (reslen = __read (fd, buf, sizeof (buf))) <= 0) + /* This also didn't work. We give up and say it's a UP machine. */ + buf[0] = '\0'; + + __close (fd); + } + + return strstr (buf, "SMP") != NULL; +} |