* sysdeps/x86_64/cacheinfo.c (init_cacheinfo): Pass correct value
[glibc.git] / posix / sched_cpucount.c
blobd7f6b7b49f0d8e9e58b8f85505e9f184aed4f393
1 /* Copyright (C) 2007 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 02111-1307 USA. */
19 #include <limits.h>
20 #include <sched.h>
23 int
24 __sched_cpucount (size_t setsize, cpu_set_t *setp)
26 int s = 0;
27 for (unsigned int j = 0; j < setsize / sizeof (__cpu_mask); ++j)
29 __cpu_mask l = setp->__bits[j];
30 if (l == 0)
31 continue;
33 #if LONG_BIT > 32
34 l = (l & 0x5555555555555555ul) + ((l >> 1) & 0x5555555555555555ul);
35 l = (l & 0x3333333333333333ul) + ((l >> 2) & 0x3333333333333333ul);
36 l = (l & 0x0f0f0f0f0f0f0f0ful) + ((l >> 4) & 0x0f0f0f0f0f0f0f0ful);
37 l = (l & 0x00ff00ff00ff00fful) + ((l >> 8) & 0x00ff00ff00ff00fful);
38 l = (l & 0x0000ffff0000fffful) + ((l >> 16) & 0x0000ffff0000fffful);
39 l = (l & 0x00000000fffffffful) + ((l >> 32) & 0x00000000fffffffful);
40 #else
41 l = (l & 0x55555555ul) + ((l >> 1) & 0x55555555ul);
42 l = (l & 0x33333333ul) + ((l >> 2) & 0x33333333ul);
43 l = (l & 0x0f0f0f0ful) + ((l >> 4) & 0x0f0f0f0ful);
44 l = (l & 0x00ff00fful) + ((l >> 8) & 0x00ff00fful);
45 l = (l & 0x0000fffful) + ((l >> 16) & 0x0000fffful);
46 #endif
48 s += l;
51 return s;