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Diffstat (limited to 'cross/lib/nproc.c')
| -rw-r--r-- | cross/lib/nproc.c | 404 |
1 files changed, 0 insertions, 404 deletions
diff --git a/cross/lib/nproc.c b/cross/lib/nproc.c deleted file mode 100644 index 2740c458c11..00000000000 --- a/cross/lib/nproc.c +++ /dev/null @@ -1,404 +0,0 @@ -/* Detect the number of processors. - - Copyright (C) 2009-2023 Free Software Foundation, Inc. - - This file is free software: you can redistribute it and/or modify - it under the terms of the GNU Lesser General Public License as - published by the Free Software Foundation; either version 2.1 of the - License, or (at your option) any later version. - - This file is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with this program. If not, see <https://www.gnu.org/licenses/>. */ - -/* Written by Glen Lenker and Bruno Haible. */ - -#include <config.h> -#include "nproc.h" - -#include <limits.h> -#include <stdlib.h> -#include <unistd.h> - -#if HAVE_PTHREAD_GETAFFINITY_NP && 0 -# include <pthread.h> -# include <sched.h> -#endif -#if HAVE_SCHED_GETAFFINITY_LIKE_GLIBC || HAVE_SCHED_GETAFFINITY_NP -# include <sched.h> -#endif - -#include <sys/types.h> - -#if HAVE_SYS_PSTAT_H -# include <sys/pstat.h> -#endif - -#if HAVE_SYS_SYSMP_H -# include <sys/sysmp.h> -#endif - -#if HAVE_SYS_PARAM_H -# include <sys/param.h> -#endif - -#if HAVE_SYS_SYSCTL_H && ! defined __GLIBC__ -# include <sys/sysctl.h> -#endif - -#if defined _WIN32 && ! defined __CYGWIN__ -# define WIN32_LEAN_AND_MEAN -# include <windows.h> -#endif - -#include "c-ctype.h" - -#include "minmax.h" - -#define ARRAY_SIZE(a) (sizeof (a) / sizeof ((a)[0])) - -/* Return the number of processors available to the current process, based - on a modern system call that returns the "affinity" between the current - process and each CPU. Return 0 if unknown or if such a system call does - not exist. */ -static unsigned long -num_processors_via_affinity_mask (void) -{ - /* glibc >= 2.3.3 with NPTL and NetBSD 5 have pthread_getaffinity_np, - but with different APIs. Also it requires linking with -lpthread. - Therefore this code is not enabled. - glibc >= 2.3.4 has sched_getaffinity whereas NetBSD 5 has - sched_getaffinity_np. */ -#if HAVE_PTHREAD_GETAFFINITY_NP && defined __GLIBC__ && 0 - { - cpu_set_t set; - - if (pthread_getaffinity_np (pthread_self (), sizeof (set), &set) == 0) - { - unsigned long count; - -# ifdef CPU_COUNT - /* glibc >= 2.6 has the CPU_COUNT macro. */ - count = CPU_COUNT (&set); -# else - size_t i; - - count = 0; - for (i = 0; i < CPU_SETSIZE; i++) - if (CPU_ISSET (i, &set)) - count++; -# endif - if (count > 0) - return count; - } - } -#elif HAVE_PTHREAD_GETAFFINITY_NP && defined __NetBSD__ && 0 - { - cpuset_t *set; - - set = cpuset_create (); - if (set != NULL) - { - unsigned long count = 0; - - if (pthread_getaffinity_np (pthread_self (), cpuset_size (set), set) - == 0) - { - cpuid_t i; - - for (i = 0;; i++) - { - int ret = cpuset_isset (i, set); - if (ret < 0) - break; - if (ret > 0) - count++; - } - } - cpuset_destroy (set); - if (count > 0) - return count; - } - } -#elif HAVE_SCHED_GETAFFINITY_LIKE_GLIBC /* glibc >= 2.3.4 */ - { - cpu_set_t set; - - if (sched_getaffinity (0, sizeof (set), &set) == 0) - { - unsigned long count; - -# ifdef CPU_COUNT - /* glibc >= 2.6 has the CPU_COUNT macro. */ - count = CPU_COUNT (&set); -# else - size_t i; - - count = 0; - for (i = 0; i < CPU_SETSIZE; i++) - if (CPU_ISSET (i, &set)) - count++; -# endif - if (count > 0) - return count; - } - } -#elif HAVE_SCHED_GETAFFINITY_NP /* NetBSD >= 5 */ - { - cpuset_t *set; - - set = cpuset_create (); - if (set != NULL) - { - unsigned long count = 0; - - if (sched_getaffinity_np (getpid (), cpuset_size (set), set) == 0) - { - cpuid_t i; - - for (i = 0;; i++) - { - int ret = cpuset_isset (i, set); - if (ret < 0) - break; - if (ret > 0) - count++; - } - } - cpuset_destroy (set); - if (count > 0) - return count; - } - } -#endif - -#if defined _WIN32 && ! defined __CYGWIN__ - { /* This works on native Windows platforms. */ - DWORD_PTR process_mask; - DWORD_PTR system_mask; - - if (GetProcessAffinityMask (GetCurrentProcess (), - &process_mask, &system_mask)) - { - DWORD_PTR mask = process_mask; - unsigned long count = 0; - - for (; mask != 0; mask = mask >> 1) - if (mask & 1) - count++; - if (count > 0) - return count; - } - } -#endif - - return 0; -} - - -/* Return the total number of processors. Here QUERY must be one of - NPROC_ALL, NPROC_CURRENT. The result is guaranteed to be at least 1. */ -static unsigned long int -num_processors_ignoring_omp (enum nproc_query query) -{ - /* On systems with a modern affinity mask system call, we have - sysconf (_SC_NPROCESSORS_CONF) - >= sysconf (_SC_NPROCESSORS_ONLN) - >= num_processors_via_affinity_mask () - The first number is the number of CPUs configured in the system. - The second number is the number of CPUs available to the scheduler. - The third number is the number of CPUs available to the current process. - - Note! On Linux systems with glibc, the first and second number come from - the /sys and /proc file systems (see - glibc/sysdeps/unix/sysv/linux/getsysstats.c). - In some situations these file systems are not mounted, and the sysconf call - returns 1 or 2 (<https://sourceware.org/bugzilla/show_bug.cgi?id=21542>), - which does not reflect the reality. */ - - if (query == NPROC_CURRENT) - { - /* Try the modern affinity mask system call. */ - { - unsigned long nprocs = num_processors_via_affinity_mask (); - - if (nprocs > 0) - return nprocs; - } - -#if defined _SC_NPROCESSORS_ONLN - { /* This works on glibc, Mac OS X 10.5, FreeBSD, AIX, OSF/1, Solaris, - Cygwin, Haiku. */ - long int nprocs = sysconf (_SC_NPROCESSORS_ONLN); - if (nprocs > 0) - return nprocs; - } -#endif - } - else /* query == NPROC_ALL */ - { -#if defined _SC_NPROCESSORS_CONF - { /* This works on glibc, Mac OS X 10.5, FreeBSD, AIX, OSF/1, Solaris, - Cygwin, Haiku. */ - long int nprocs = sysconf (_SC_NPROCESSORS_CONF); - -# if __GLIBC__ >= 2 && defined __linux__ - /* On Linux systems with glibc, this information comes from the /sys and - /proc file systems (see glibc/sysdeps/unix/sysv/linux/getsysstats.c). - In some situations these file systems are not mounted, and the - sysconf call returns 1 or 2. But we wish to guarantee that - num_processors (NPROC_ALL) >= num_processors (NPROC_CURRENT). */ - if (nprocs == 1 || nprocs == 2) - { - unsigned long nprocs_current = num_processors_via_affinity_mask (); - - if (/* nprocs_current > 0 && */ nprocs_current > nprocs) - nprocs = nprocs_current; - } -# endif - - if (nprocs > 0) - return nprocs; - } -#endif - } - -#if HAVE_PSTAT_GETDYNAMIC - { /* This works on HP-UX. */ - struct pst_dynamic psd; - if (pstat_getdynamic (&psd, sizeof psd, 1, 0) >= 0) - { - /* The field psd_proc_cnt contains the number of active processors. - In newer releases of HP-UX 11, the field psd_max_proc_cnt includes - deactivated processors. */ - if (query == NPROC_CURRENT) - { - if (psd.psd_proc_cnt > 0) - return psd.psd_proc_cnt; - } - else - { - if (psd.psd_max_proc_cnt > 0) - return psd.psd_max_proc_cnt; - } - } - } -#endif - -#if HAVE_SYSMP && defined MP_NAPROCS && defined MP_NPROCS - { /* This works on IRIX. */ - /* MP_NPROCS yields the number of installed processors. - MP_NAPROCS yields the number of processors available to unprivileged - processes. */ - int nprocs = - sysmp (query == NPROC_CURRENT && getuid () != 0 - ? MP_NAPROCS - : MP_NPROCS); - if (nprocs > 0) - return nprocs; - } -#endif - - /* Finally, as fallback, use the APIs that don't distinguish between - NPROC_CURRENT and NPROC_ALL. */ - -#if HAVE_SYSCTL && ! defined __GLIBC__ && defined HW_NCPU - { /* This works on macOS, FreeBSD, NetBSD, OpenBSD. - macOS 10.14 does not allow mib to be const. */ - int nprocs; - size_t len = sizeof (nprocs); - static int mib[][2] = { -# ifdef HW_NCPUONLINE - { CTL_HW, HW_NCPUONLINE }, -# endif - { CTL_HW, HW_NCPU } - }; - for (int i = 0; i < ARRAY_SIZE (mib); i++) - { - if (sysctl (mib[i], ARRAY_SIZE (mib[i]), &nprocs, &len, NULL, 0) == 0 - && len == sizeof (nprocs) - && 0 < nprocs) - return nprocs; - } - } -#endif - -#if defined _WIN32 && ! defined __CYGWIN__ - { /* This works on native Windows platforms. */ - SYSTEM_INFO system_info; - GetSystemInfo (&system_info); - if (0 < system_info.dwNumberOfProcessors) - return system_info.dwNumberOfProcessors; - } -#endif - - return 1; -} - -/* Parse OMP environment variables without dependence on OMP. - Return 0 for invalid values. */ -static unsigned long int -parse_omp_threads (char const* threads) -{ - unsigned long int ret = 0; - - if (threads == NULL) - return ret; - - /* The OpenMP spec says that the value assigned to the environment variables - "may have leading and trailing white space". */ - while (*threads != '\0' && c_isspace (*threads)) - threads++; - - /* Convert it from positive decimal to 'unsigned long'. */ - if (c_isdigit (*threads)) - { - char *endptr = NULL; - unsigned long int value = strtoul (threads, &endptr, 10); - - if (endptr != NULL) - { - while (*endptr != '\0' && c_isspace (*endptr)) - endptr++; - if (*endptr == '\0') - return value; - /* Also accept the first value in a nesting level, - since we can't determine the nesting level from env vars. */ - else if (*endptr == ',') - return value; - } - } - - return ret; -} - -unsigned long int -num_processors (enum nproc_query query) -{ - unsigned long int omp_env_limit = ULONG_MAX; - - if (query == NPROC_CURRENT_OVERRIDABLE) - { - unsigned long int omp_env_threads; - /* Honor the OpenMP environment variables, recognized also by all - programs that are based on OpenMP. */ - omp_env_threads = parse_omp_threads (getenv ("OMP_NUM_THREADS")); - omp_env_limit = parse_omp_threads (getenv ("OMP_THREAD_LIMIT")); - if (! omp_env_limit) - omp_env_limit = ULONG_MAX; - - if (omp_env_threads) - return MIN (omp_env_threads, omp_env_limit); - - query = NPROC_CURRENT; - } - /* Here query is one of NPROC_ALL, NPROC_CURRENT. */ - { - unsigned long nprocs = num_processors_ignoring_omp (query); - return MIN (nprocs, omp_env_limit); - } -} |