diff options
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/smp.h')
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/smp.h | 30 |
1 files changed, 27 insertions, 3 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/smp.h b/nptl/sysdeps/unix/sysv/linux/smp.h index fcc34f7681..4f4d358d32 100644 --- a/nptl/sysdeps/unix/sysv/linux/smp.h +++ b/nptl/sysdeps/unix/sysv/linux/smp.h @@ -1,5 +1,5 @@ /* Determine whether the host has multiple processors. Linux version. - Copyright (C) 1996, 2002, 2004, 2006 Free Software Foundation, Inc. + Copyright (C) 1996, 2002, 2004 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 @@ -17,12 +17,36 @@ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ +#include <errno.h> +#include <fcntl.h> +#include <string.h> +#include <sys/sysctl.h> +#include <not-cancel.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) { - /* Assume all machines are SMP and/or CMT and/or SMT. */ - return 1; + 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_not_cancel_2 ("/proc/sys/kernel/version", O_RDONLY); + if (__builtin_expect (fd, 0) == -1 + || (reslen = read_not_cancel (fd, buf, sizeof (buf))) <= 0) + /* This also didn't work. We give up and say it's a UP machine. */ + buf[0] = '\0'; + + close_not_cancel_no_status (fd); + } + + return strstr (buf, "SMP") != NULL; } |