1 ///////////////////////////////////////////////////////////////////////////////
2 //
3 /// \file tuklib_cpucores.c
4 /// \brief Get the number of CPU cores online
5 //
6 // Author: Lasse Collin
7 //
8 // This file has been put into the public domain.
9 // You can do whatever you want with this file.
10 //
11 ///////////////////////////////////////////////////////////////////////////////
12
13 #include "tuklib_cpucores.h"
14
15 #if defined(_WIN32) || defined(__CYGWIN__)
16 # ifndef _WIN32_WINNT
17 # define _WIN32_WINNT 0x0500
18 # endif
19 # include <windows.h>
20
21 // glibc >= 2.9
22 #elif defined(TUKLIB_CPUCORES_SCHED_GETAFFINITY)
23 # include <sched.h>
24
25 // FreeBSD
26 #elif defined(TUKLIB_CPUCORES_CPUSET)
27 # include <sys/param.h>
28 # include <sys/cpuset.h>
29
30 #elif defined(TUKLIB_CPUCORES_SYSCTL)
31 # ifdef HAVE_SYS_PARAM_H
32 # include <sys/param.h>
33 # endif
34 # include <sys/sysctl.h>
35
36 #elif defined(TUKLIB_CPUCORES_SYSCONF)
37 # include <unistd.h>
38
39 // HP-UX
40 #elif defined(TUKLIB_CPUCORES_PSTAT_GETDYNAMIC)
41 # include <sys/param.h>
42 # include <sys/pstat.h>
43 #endif
44
45
46 extern uint32_t
tuklib_cpucores(void)47 tuklib_cpucores(void)
48 {
49 uint32_t ret = 0;
50
51 #if defined(_WIN32) || defined(__CYGWIN__)
52 SYSTEM_INFO sysinfo;
53 GetSystemInfo(&sysinfo);
54 ret = sysinfo.dwNumberOfProcessors;
55
56 #elif defined(TUKLIB_CPUCORES_SCHED_GETAFFINITY)
57 cpu_set_t cpu_mask;
58 if (sched_getaffinity(0, sizeof(cpu_mask), &cpu_mask) == 0)
59 ret = (uint32_t)CPU_COUNT(&cpu_mask);
60
61 #elif defined(TUKLIB_CPUCORES_CPUSET)
62 cpuset_t set;
63 if (cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_PID, -1,
64 sizeof(set), &set) == 0) {
65 # ifdef CPU_COUNT
66 ret = (uint32_t)CPU_COUNT(&set);
67 # else
68 for (unsigned i = 0; i < CPU_SETSIZE; ++i)
69 if (CPU_ISSET(i, &set))
70 ++ret;
71 # endif
72 }
73
74 #elif defined(TUKLIB_CPUCORES_SYSCTL)
75 int name[2] = { CTL_HW, HW_NCPU };
76 int cpus;
77 size_t cpus_size = sizeof(cpus);
78 if (sysctl(name, 2, &cpus, &cpus_size, NULL, 0) != -1
79 && cpus_size == sizeof(cpus) && cpus > 0)
80 ret = (uint32_t)cpus;
81
82 #elif defined(TUKLIB_CPUCORES_SYSCONF)
83 # ifdef _SC_NPROCESSORS_ONLN
84 // Most systems
85 const long cpus = sysconf(_SC_NPROCESSORS_ONLN);
86 # else
87 // IRIX
88 const long cpus = sysconf(_SC_NPROC_ONLN);
89 # endif
90 if (cpus > 0)
91 ret = (uint32_t)cpus;
92
93 #elif defined(TUKLIB_CPUCORES_PSTAT_GETDYNAMIC)
94 struct pst_dynamic pst;
95 if (pstat_getdynamic(&pst, sizeof(pst), 1, 0) != -1)
96 ret = (uint32_t)pst.psd_proc_cnt;
97 #endif
98
99 return ret;
100 }
101