mirror/glibc
2
0
Fork 0
mirror of git://sourceware.org/git/glibc.git synced 2025-01-18 12:16:13 +08:00
Code Issues Packages Projects Releases Wiki Activity

* sysdeps/unix/sysv/linux/getsysstats.c (__get_nprocs): Using

Browse Source 
/proc is faster and sufficient.  /sys is still needed for
	__get_nprocs_conf.
This commit is contained in:
Ulrich Drepper 2007-08-01 21:23:59 +00:00
parent 5e0923ab31
commit 0abf17decf
2 changed files with 11 additions and 59 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
ChangeLog
View File

@ -1,3 +1,9 @@
2007-08-01 Ulrich Drepper <drepper@redhat.com>
* sysdeps/unix/sysv/linux/getsysstats.c (__get_nprocs): Using
/proc is faster and sufficient. /sys is still needed for
__get_nprocs_conf.
2007-08-01 Jakub Jelinek <jakub@redhat.com> 2007-08-01 Jakub Jelinek <jakub@redhat.com>
* sysdeps/unix/sysv/linux/i386/syscalls.list (fallocate): Add fallocate * sysdeps/unix/sysv/linux/i386/syscalls.list (fallocate): Add fallocate

64
sysdeps/unix/sysv/linux/getsysstats.c
View File

@ -68,9 +68,11 @@
#endif #endif
static int int
count_processors_in_proc (void) __get_nprocs ()
{ {
/* XXX Here will come a test for the new system call. */
char buffer[8192]; char buffer[8192];
int result = 1; int result = 1;
@ -102,62 +104,6 @@ count_processors_in_proc (void)
return result; return result;
} }
int
__get_nprocs ()
{
/* XXX Here will come a test for the new system call. */
/* Try to use the sysfs filesystem. It has actual information about
online processors. */
DIR *dir = __opendir ("/sys/devices/system/cpu");
if (dir != NULL)
{
int dfd = dirfd (dir);
int count = 0;
struct dirent64 *d;
while ((d = __readdir64 (dir)) != NULL)
/* NB: the sysfs has d_type support. */
if (d->d_type == DT_DIR && strncmp (d->d_name, "cpu", 3) == 0)
{
char *endp;
unsigned long int nr = strtoul (d->d_name + 3, &endp, 10);
if (nr != ULONG_MAX && endp != d->d_name + 3 && *endp == '\0')
{
/* Try reading the online file. */
char oname[_D_ALLOC_NAMLEN (d) + sizeof "/online"];
strcpy (stpcpy (oname, d->d_name), "/online");
/* We unconditionally use openat since the "online"
file became readable only after the openat system
call was introduced. */
char buf[1];
int fd = openat_not_cancel_3 (dfd, oname, O_RDONLY);
/* If we cannot read the online file we have to assume
the CPU is online. */
if (fd < 0)
++count;
else
{
if (read_not_cancel (fd, buf, sizeof (buf)) < 0
|| buf[0] == '1')
++count;
close_not_cancel_no_status (fd);
}
}
}
__closedir (dir);
return count;
}
return count_processors_in_proc ();
}
weak_alias (__get_nprocs, get_nprocs) weak_alias (__get_nprocs, get_nprocs)
@ -206,7 +152,7 @@ __get_nprocs_conf ()
fclose (fp); fclose (fp);
} }
#else #else
result = count_processors_in_proc (); result = __get_nprocs ();
#endif #endif
return result; return result;