bug-gnulib
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PATCH] core-count: A new program to count the number of cpu cores


From: Giuseppe Scrivano
Subject: Re: [PATCH] core-count: A new program to count the number of cpu cores
Date: Sat, 31 Oct 2009 17:46:25 +0100
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1.50 (gnu/linux)

Hi,

I included what we have discussed into my patch.  I renamed the new
program to `nproc', now it accepts two options: --available and
--installed.
By default --available is used, if --available is not know then
--installed is used.

I added another test to ensure nproc --available <= nproc --installed.

Any comment?


Cheers,
Giuseppe


>From 4665e1801f73eeba98cad9988c5d5829bad03a37 Mon Sep 17 00:00:00 2001
From: Giuseppe Scrivano <address@hidden>
Date: Sun, 25 Oct 2009 19:04:41 +0100
Subject: [PATCH] nproc: A new program to count the number of processors

* AUTHORS: Add my name.
* NEWS: Mention it.
* bootstrap.conf (gnulib_modules): Add nproc and pthread.
* doc/coreutils.texi (nproc invocation): Add nproc info.
* src/Makefile.am (EXTRA_PROGRAMS): Add nproc.
* src/nproc.c: New file.
* tests/Makefile.am (TESTS): Add nproc/{avail, cpuinfo, positive}.
* tests/nproc/avail: New file.
* tests/nproc/cpuinfo: New file.
* tests/nproc/positive: New file.
---
 AUTHORS              |    1 +
 NEWS                 |    4 +
 bootstrap.conf       |    2 +
 doc/coreutils.texi   |   39 +++++++++++++
 src/Makefile.am      |    3 +
 src/nproc.c          |  155 ++++++++++++++++++++++++++++++++++++++++++++++++++
 tests/Makefile.am    |    3 +
 tests/nproc/avail    |   33 +++++++++++
 tests/nproc/cpuinfo  |   34 +++++++++++
 tests/nproc/positive |   33 +++++++++++
 10 files changed, 307 insertions(+), 0 deletions(-)
 create mode 100644 src/nproc.c
 create mode 100644 tests/nproc/avail
 create mode 100755 tests/nproc/cpuinfo
 create mode 100755 tests/nproc/positive

diff --git a/AUTHORS b/AUTHORS
index 7095db0..3855622 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -51,6 +51,7 @@ mv: Mike Parker, David MacKenzie, Jim Meyering
 nice: David MacKenzie
 nl: Scott Bartram, David MacKenzie
 nohup: Jim Meyering
+nproc: Giuseppe Scrivano
 od: Jim Meyering
 paste: David M. Ihnat, David MacKenzie
 pathchk: Paul Eggert, David MacKenzie, Jim Meyering
diff --git a/NEWS b/NEWS
index 1ed577f..4caa747 100644
--- a/NEWS
+++ b/NEWS
@@ -32,6 +32,10 @@ GNU coreutils NEWS                                    -*- 
outline -*-
   with the invoked command failing with status 1.  Likewise, nohup
   fails with status 125 instead of 127.
 
+** New programs
+
+  nproc: A new program to get the number of processors.
+
 ** New features
 
   md5sum --check now also accepts openssl-style checksums.
diff --git a/bootstrap.conf b/bootstrap.conf
index 1857489..67e2672 100644
--- a/bootstrap.conf
+++ b/bootstrap.conf
@@ -157,6 +157,7 @@ gnulib_modules="
   modechange
   mountlist
   mpsort
+  nproc
   obstack
   pathmax
   perl
@@ -167,6 +168,7 @@ gnulib_modules="
   priv-set
   progname
   propername
+  pthread
   putenv
   quote
   quotearg
diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index c54ffb8..588150b 100644
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -84,6 +84,7 @@
 * nice: (coreutils)nice invocation.             Modify niceness.
 * nl: (coreutils)nl invocation.                 Number lines and write files.
 * nohup: (coreutils)nohup invocation.           Immunize to hangups.
+* nproc: (coreutils)nproc invocation.           Print the number of processors.
 * od: (coreutils)od invocation.                 Dump files in octal, etc.
 * paste: (coreutils)paste invocation.           Merge lines of files.
 * pathchk: (coreutils)pathchk invocation.       Check file name portability.
@@ -409,6 +410,7 @@ System context
 
 * arch invocation::              Print machine hardware name
 * date invocation::              Print or set system date and time
+* nproc invocation::             Print the number of processors
 * uname invocation::             Print system information
 * hostname invocation::          Print or set system name
 * hostid invocation::            Print numeric host identifier
@@ -13221,6 +13223,7 @@ information.
 @menu
 * date invocation::             Print or set system date and time.
 * arch invocation::             Print machine hardware name.
+* nproc invocation::            Print the number of processors.
 * uname invocation::            Print system information.
 * hostname invocation::         Print or set system name.
 * hostid invocation::           Print numeric host identifier.
@@ -13880,6 +13883,42 @@ The program accepts the @ref{Common options} only.
 @exitstatus
 
 
address@hidden nproc invocation
address@hidden @command{nproc}: Print the number of processors
+
address@hidden nproc
address@hidden Print the number of processors
address@hidden system information, printing
+
address@hidden prints the number of processors.  It is not a hardware
+inspection tool but a portable way to get how many processes
+potentially can be executed in parallel.  The result is guaranteed  to
+be a non-zero positive number.  Synopsis:
+
address@hidden
+nproc address@hidden
address@hidden example
+
+The program accepts the following options.  Also see @ref{Common options}.
+
address@hidden @samp
+
address@hidden --available
address@hidden --available
+Print the number of processors available to the current process.  It
+may be less than the number of installed processors.
+If this information is not accessible, then nproc returs the number of
+installed processors.  By default --available is used.
+
address@hidden --installed
address@hidden --installed
+Print the number of installed processors.
+
address@hidden table
+
address@hidden
+
+
 @node uname invocation
 @section @command{uname}: Print system information
 
diff --git a/src/Makefile.am b/src/Makefile.am
index 67c29cc..a6dc5ff 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -86,6 +86,7 @@ EXTRA_PROGRAMS = \
   mktemp       \
   mv           \
   nl           \
+  nproc                \
   nohup                \
   od           \
   paste                \
@@ -189,6 +190,7 @@ chown_LDADD = $(LDADD)
 chroot_LDADD = $(LDADD)
 cksum_LDADD = $(LDADD)
 comm_LDADD = $(LDADD)
+nproc_LDADD = $(LDADD) $(LIB_PTHREAD)
 cp_LDADD = $(LDADD)
 csplit_LDADD = $(LDADD)
 cut_LDADD = $(LDADD)
@@ -480,6 +482,7 @@ rmdir_SOURCES = rmdir.c prog-fprintf.c
 
 uname_SOURCES = uname.c uname-uname.c
 arch_SOURCES = uname.c uname-arch.c
+nproc_SOURCES = nproc.c
 
 md5sum_SOURCES = md5sum.c
 md5sum_CPPFLAGS = -DHASH_ALGO_MD5=1 $(AM_CPPFLAGS)
diff --git a/src/nproc.c b/src/nproc.c
new file mode 100644
index 0000000..2449fc9
--- /dev/null
+++ b/src/nproc.c
@@ -0,0 +1,155 @@
+/* nproc - print the number of processors.
+   Copyright (C) 2009 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Giuseppe Scrivano.  */
+
+#include <config.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <sys/types.h>
+
+#include "system.h"
+#include "pthread.h"
+#include "nproc.h"
+
+/* The official name of this program (e.g., no `g' prefix).  */
+#define PROGRAM_NAME "nproc"
+
+#define AUTHORS proper_name ("Giuseppe Scrivano")
+
+enum
+{
+  AVAILABLE_OPTION = CHAR_MAX + 1,
+  INSTALLED_OPTION
+};
+
+static struct option const longopts[] =
+{
+  {"installed", no_argument, NULL, INSTALLED_OPTION},
+  {"available", no_argument, NULL, AVAILABLE_OPTION},
+  {GETOPT_HELP_OPTION_DECL},
+  {GETOPT_VERSION_OPTION_DECL},
+  {NULL, 0, NULL, 0}
+};
+
+void
+usage (int status)
+{
+  if (status != EXIT_SUCCESS)
+    fprintf (stderr, _("Try `%s --help' for more information.\n"),
+             program_name);
+  else
+    {
+      printf (_("Usage: %s [OPTION]...\n"), program_name);
+      fputs (_("\
+Print the number of online cpu cores.\n\
+\n\
+"), stdout);
+      fputs (_("\
+      --available          report the number of processors available to the\n \
+                           current process.\n \
+      --installed          return the number of installed processors\n\
+"), stdout);
+
+      fputs (HELP_OPTION_DESCRIPTION, stdout);
+      fputs (VERSION_OPTION_DESCRIPTION, stdout);
+      emit_ancillary_info ();
+    }
+  exit (status);
+}
+
+/* Compute the number of available processors.  Return 0 on error.  */
+
+static u_long
+nproc_available ()
+{
+  u_long nproc = 0;
+
+#ifdef CPU_SETSIZE
+  size_t j;
+  cpu_set_t cpuset;
+  CPU_ZERO (&cpuset);
+
+  if (pthread_getaffinity_np (pthread_self (), sizeof (cpu_set_t), &cpuset))
+    return 0;
+
+  for (j = 0; j < CPU_SETSIZE; j++)
+    if (CPU_ISSET (j, &cpuset))
+      nproc++;
+#endif
+
+  return nproc;
+}
+
+/* Compute the number of processors.  If AVAILABLE returns the number
+   of processors available to the current process, otherwise the number
+   of installed processors.  In case the number of available processors
+   can't be computed rollback to the installed processors.  The result is
+   guaranteed to be at least 1.  */
+
+static u_long
+nproc (bool available)
+{
+  if (available)
+    {
+      u_long available_proc = nproc_available ();
+      if (available_proc)
+        return available_proc;
+    }
+
+  return num_processors ();
+}
+
+int
+main (int argc, char **argv)
+{
+  bool available = true;
+  initialize_main (&argc, &argv);
+  set_program_name (argv[0]);
+  setlocale (LC_ALL, "");
+  bindtextdomain (PACKAGE, LOCALEDIR);
+  textdomain (PACKAGE);
+
+  atexit (close_stdout);
+
+  while (1)
+    {
+      int c = getopt_long (argc, argv, "", longopts, NULL);
+      if (c == -1)
+        break;
+      switch (c)
+        {
+        case_GETOPT_HELP_CHAR;
+
+        case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
+
+        case AVAILABLE_OPTION:
+          available = true;
+          break;
+
+        case INSTALLED_OPTION:
+          available = false;
+          break;
+
+        default:
+          usage (EXIT_FAILURE);
+        }
+    }
+
+  printf ("%u\n", nproc (available));
+
+  exit (EXIT_SUCCESS);
+}
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 03fe6f1..dd2beee 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -458,6 +458,9 @@ TESTS =                                             \
   touch/read-only                              \
   touch/relative                               \
   touch/trailing-slash                         \
+  nproc/avail                          \
+  nproc/cpuinfo                                \
+  nproc/positive                               \
   $(root_tests)
 
 pr_data =                                      \
diff --git a/tests/nproc/avail b/tests/nproc/avail
new file mode 100644
index 0000000..2543e5b
--- /dev/null
+++ b/tests/nproc/avail
@@ -0,0 +1,33 @@
+#!/bin/sh
+# Ensure that nproc --installed is greater or equal to nproc --available.
+
+# Copyright (C) 2009 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program 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 General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+if test "$VERBOSE" = yes; then
+  set -x
+  nproc --version
+fi
+
+. $srcdir/test-lib.sh
+
+fail=0
+
+available=$(nproc --available)
+installed=$(nproc --installed)
+
+test $installed -ge $available || fail=1
+
+Exit $fail
diff --git a/tests/nproc/cpuinfo b/tests/nproc/cpuinfo
new file mode 100755
index 0000000..3a3abe6
--- /dev/null
+++ b/tests/nproc/cpuinfo
@@ -0,0 +1,34 @@
+#!/bin/sh
+# Check that the number of cores reported by nproc is equal to the number
+# of cores listed in /proc/cpuinfo, when it is available
+
+# Copyright (C) 2009 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+if test "$VERBOSE" = yes; then
+  set -x
+  nproc --version
+fi
+
+. $srcdir/test-lib.sh
+
+test -r /proc/cpuinfo || skip_test_
+
+fail=0
+cores=$(nproc)
+
+test $(grep '^proc' /proc/cpuinfo  | wc -l) -eq $cores || fail=1
+
+Exit $fail
diff --git a/tests/nproc/positive b/tests/nproc/positive
new file mode 100755
index 0000000..acdba78
--- /dev/null
+++ b/tests/nproc/positive
@@ -0,0 +1,33 @@
+#!/bin/sh
+# Ensure that nproc returns a non-zero positive number
+
+# Copyright (C) 2009 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+if test "$VERBOSE" = yes; then
+  set -x
+  nproc --version
+fi
+
+. $srcdir/test-lib.sh
+
+fail=0
+
+for opt in --available --installed; do
+    cores=$(nproc $opt)
+    test $cores -gt 0 || fail=1
+done
+
+Exit $fail
-- 
1.6.5




reply via email to

[Prev in Thread] Current Thread [Next in Thread]