summaryrefslogtreecommitdiff
path: root/linuxthreads/sysdeps/unix/sysv/linux/smp.h
diff options
context:
space:
mode:
Diffstat (limited to 'linuxthreads/sysdeps/unix/sysv/linux/smp.h')
-rw-r--r--linuxthreads/sysdeps/unix/sysv/linux/smp.h48
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;
+}