1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
|
#
# SYNOPSIS
#
# TUKLIB_CPUCORES
#
# DESCRIPTION
#
# Check how to find out the number of available CPU cores in the system.
# This information is used by tuklib_cpucores.c.
#
# Supported methods:
# - GetSystemInfo(): Windows (including Cygwin)
# - sched_getaffinity(): glibc (GNU/Linux, GNU/kFreeBSD)
# - cpuset_getaffinity(): FreeBSD
# - sysctl(): BSDs, OS/2
# - sysconf(): GNU/Linux, Solaris, Tru64, IRIX, AIX, QNX, Cygwin (but
# GetSystemInfo() is used on Cygwin)
# - pstat_getdynamic(): HP-UX
#
# COPYING
#
# Author: Lasse Collin
#
# This file has been put into the public domain.
# You can do whatever you want with this file.
#
AC_DEFUN_ONCE([TUKLIB_CPUCORES], [
AC_REQUIRE([TUKLIB_COMMON])
# sys/param.h might be needed by sys/sysctl.h.
AC_CHECK_HEADERS([sys/param.h])
AC_CACHE_CHECK([how to detect the number of available CPU cores],
[tuklib_cv_cpucores_method], [
# Maybe checking $host_os would be enough but this matches what
# tuklib_cpucores.c does.
#
# NOTE: IRIX has a compiler that doesn't error out with #error, so use
# a non-compilable text instead of #error to generate an error.
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
#if defined(_WIN32) || defined(__CYGWIN__)
int main(void) { return 0; }
#else
compile error
#endif
]])], [tuklib_cv_cpucores_method=special], [
# glibc-based systems (GNU/Linux and GNU/kFreeBSD) have sched_getaffinity().
# The CPU_COUNT() macro was added in glibc 2.9 so we try to link the
# test program instead of merely compiling it. glibc 2.9 is old enough that
# if someone uses the code on older glibc, the fallback to sysconf() should
# be good enough.
AC_LINK_IFELSE([AC_LANG_SOURCE([[
#include <sched.h>
int
main(void)
{
cpu_set_t cpu_mask;
sched_getaffinity(0, sizeof(cpu_mask), &cpu_mask);
return CPU_COUNT(&cpu_mask);
}
]])], [tuklib_cv_cpucores_method=sched_getaffinity], [
# FreeBSD has both cpuset and sysctl. Look for cpuset first because
# it's a better approach.
#
# This test would match on GNU/kFreeBSD too but it would require
# -lfreebsd-glue when linking and thus in the current form this would
# fail on GNU/kFreeBSD. The above test for sched_getaffinity() matches
# on GNU/kFreeBSD so the test below should never run on that OS.
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
#include <sys/param.h>
#include <sys/cpuset.h>
int
main(void)
{
cpuset_t set;
cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_PID, -1,
sizeof(set), &set);
return 0;
}
]])], [tuklib_cv_cpucores_method=cpuset], [
# On OS/2, both sysconf() and sysctl() pass the tests in this file,
# but only sysctl() works. On QNX it's the opposite: only sysconf() works
# (although it assumes that _POSIX_SOURCE, _XOPEN_SOURCE, and _POSIX_C_SOURCE
# are undefined or alternatively _QNX_SOURCE is defined).
#
# We test sysctl() first and intentionally break the sysctl() test on QNX
# so that sysctl() is never used on QNX.
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
#ifdef __QNX__
compile error
#endif
#ifdef HAVE_SYS_PARAM_H
# include <sys/param.h>
#endif
#include <sys/sysctl.h>
int
main(void)
{
#ifdef HW_NCPUONLINE
/* This is preferred on OpenBSD, see tuklib_cpucores.c. */
int name[2] = { CTL_HW, HW_NCPUONLINE };
#else
int name[2] = { CTL_HW, HW_NCPU };
#endif
int cpus;
size_t cpus_size = sizeof(cpus);
sysctl(name, 2, &cpus, &cpus_size, NULL, 0);
return 0;
}
]])], [tuklib_cv_cpucores_method=sysctl], [
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
#include <unistd.h>
int
main(void)
{
long i;
#ifdef _SC_NPROCESSORS_ONLN
/* Many systems using sysconf() */
i = sysconf(_SC_NPROCESSORS_ONLN);
#else
/* IRIX */
i = sysconf(_SC_NPROC_ONLN);
#endif
return 0;
}
]])], [tuklib_cv_cpucores_method=sysconf], [
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
#include <sys/param.h>
#include <sys/pstat.h>
int
main(void)
{
struct pst_dynamic pst;
pstat_getdynamic(&pst, sizeof(pst), 1, 0);
(void)pst.psd_proc_cnt;
return 0;
}
]])], [tuklib_cv_cpucores_method=pstat_getdynamic], [
tuklib_cv_cpucores_method=unknown
])])])])])])])
case $tuklib_cv_cpucores_method in
sched_getaffinity)
AC_DEFINE([TUKLIB_CPUCORES_SCHED_GETAFFINITY], [1],
[Define to 1 if the number of available CPU cores
can be detected with sched_getaffinity()])
;;
cpuset)
AC_DEFINE([TUKLIB_CPUCORES_CPUSET], [1],
[Define to 1 if the number of available CPU cores
can be detected with cpuset(2).])
;;
sysctl)
AC_DEFINE([TUKLIB_CPUCORES_SYSCTL], [1],
[Define to 1 if the number of available CPU cores
can be detected with sysctl().])
;;
sysconf)
AC_DEFINE([TUKLIB_CPUCORES_SYSCONF], [1],
[Define to 1 if the number of available CPU cores
can be detected with sysconf(_SC_NPROCESSORS_ONLN)
or sysconf(_SC_NPROC_ONLN).])
;;
pstat_getdynamic)
AC_DEFINE([TUKLIB_CPUCORES_PSTAT_GETDYNAMIC], [1],
[Define to 1 if the number of available CPU cores
can be detected with pstat_getdynamic().])
;;
esac
])dnl
|
