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-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;
+}