From c49ad96cae0e067034350309b611ed798834cdda Mon Sep 17 00:00:00 2001
From: Glenn Strauss <gstrauss@gluelogic.com>
Date: Sun, 18 Sep 2016 00:35:08 -0400
Subject: [PATCH] Run - detect num active CPUs

github: fixes #2, fixes #16
---
 UnixBench/Run | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/UnixBench/Run b/UnixBench/Run
index 1a7ebf6..a16a5c9 100755
--- a/UnixBench/Run
+++ b/UnixBench/Run
@@ -670,6 +670,9 @@ sub processCpuFlags {
 # array of N entries, one per CPU, where each entry is a hash containing
 # these fields:
 # describing the model etc.  Returns undef if the information can't be got.
+#
+# future: on systems without /proc/cpuinfo, might check for Perl modules:
+#   Sys::Info::Device::CPU or Sys::CpuAffinity
 sub getCpuInfo {
     if (!("$^O" eq "darwin")) {
         open(my $fd, "<", "/proc/cpuinfo") || return undef;
@@ -716,6 +719,39 @@ sub getCpuInfo {
 }
 
 
+# Get number of available (active) CPUs (not including disabled CPUs)
+# or, if not num of available CPUs, the total number of CPUs on the system
+# Returns undef if the information can't be obtained.
+#
+# There is no shortage of platform-specific methods to obtain this info.
+# This routine -is not- exhaustive, but adds some additional portability.
+# Most modern unix systems implement sysconf(_SC_NPROCESSORS_ONLN).
+sub getNumActiveCpus {
+    my $numCpus;
+
+    #(POSIX::_SC_NPROCESSORS_ONLN value not typically provided by POSIX.pm)
+    #$numCpus = POSIX::sysconf(POSIX::_SC_NPROCESSORS_ONLN);
+    #if (defined($numCpus)) { chomp $numCpus; return $numCpus if $numCpus; }
+
+    $numCpus = `getconf _NPROCESSORS_ONLN 2>/dev/null`;
+    if (defined($numCpus)) { chomp $numCpus; return $numCpus if $numCpus; }
+
+    $numCpus = `getconf NPROCESSORS_ONLN 2>/dev/null`;
+    if (defined($numCpus)) { chomp $numCpus; return $numCpus if $numCpus; }
+
+    $numCpus = `nproc 2>/dev/null`;
+    if (defined($numCpus)) { chomp $numCpus; return $numCpus if $numCpus; }
+
+    $numCpus = `python -c 'import os; print os.sysconf(os.sysconf_names["SC_NPROCESSORS_ONLN"]);' 2>/dev/null`;
+    if (defined($numCpus)) { chomp $numCpus; return $numCpus if $numCpus; }
+
+    # Windows
+    return $ENV{"NUMBER_OF_PROCESSORS"} if $ENV{"NUMBER_OF_PROCESSORS"};
+
+    return undef;
+}
+
+
 # Get information on the host system.  Returns a reference to a hash
 # with the following fields:
 #    name           Host name
@@ -766,6 +802,12 @@ sub getSystemInfo {
         $info->{'numCpus'} = scalar(@$cpus);
     }
 
+    # Get available number of CPUs (not disabled CPUs), if possible.
+    my $numCpus = getNumActiveCpus();
+    if (defined($numCpus)) {
+        $info->{'numCpus'} = $numCpus; # overwrite value from getCpuinfo()
+    }
+
     # Get graphics hardware info.
     $info->{'graphics'} = getCmdOutput("3dinfo | cut -f1 -d\'(\'");