Fixed #5135 - Facter returns physicalprocessorcount => 0 on a physical computer

2 files changed, 87 insertions, 6 deletions

diff --git a/lib/facter/physicalprocessorcount.rb b/lib/facter/physicalprocessorcount.rb
index 9c59614..c6145dc 100644
--- a/lib/facter/physicalprocessorcount.rb
+++ b/lib/facter/physicalprocessorcount.rb
@@ -3,16 +3,57 @@
 # Purpose: Return the number of physical processors.
 #
 # Resolution:
-#   On linux, parses the output of '/proc/cpuinfo' for the number of unique
-#   lines with "physical id" in them.
+#
+#   Attempts to use sysfs to get the physical IDs of the processors. Falls
+#   back to /proc/cpuinfo and "physical id" if sysfs is not available.
 #
 # Caveats:
 #
+Facter.add('physicalprocessorcount') do
+  confine :kernel => :linux
+
+  setcode do
+    sysfs_cpu_directory = '/sys/devices/system/cpu' # This should always be there ...
+
+    if File.exists?(sysfs_cpu_directory)
+      #
+      # We assume that the sysfs file system has the correct number of entries
+      # under the "/sys/device/system/cpu" directory and if so then we process
+      # content of the file "physical_package_id" located inside the "topology"
+      # directory in each of the per-CPU sub-directories.
+      #
+      # As per Linux Kernel documentation and the file "cputopology.txt" located
+      # inside the "/usr/src/linux/Documentation" directory we can find following
+      # short explanation:
+      #
+      # (...)
+      #
+      # 1) /sys/devices/system/cpu/cpuX/topology/physical_package_id:
+      #
+      #         physical package id of cpuX. Typically corresponds to a physical
+      #         socket number, but the actual value is architecture and platform
+      #         dependent.
+      #
+      # (...)
+      #
+      lookup_pattern = "#{sysfs_cpu_directory}" +
+        "/cpu*/topology/physical_package_id"
+
+      ids = Dir.glob(lookup_pattern).collect { |f| Facter::Util::Resolution.exec("cat #{f}")}
+
+      ids = ids.join if ids.is_a?(Array)
+      ids.scan(/\d+/).uniq.size
 
-Facter.add("physicalprocessorcount") do
-    confine :kernel => :linux
+    else
+      #
+      # Try to count number of CPUs using the proc file system next ...
+      #
+      # We assume that /proc/cpuinfo has what we need and is so then we need
+      # to make sure that we only count unique entries ...
+      #
+      str = Facter::Util::Resolution.exec("grep 'physical.\\+:' /proc/cpuinfo")
 
-    setcode do
-        ppcount = Facter::Util::Resolution.exec('grep "physical id" /proc/cpuinfo|cut -d: -f 2|sort -u|wc -l')
+      if not str.nil? then str.scan(/\d+/).uniq.size; end
     end
+  end
 end
diff --git a/spec/unit/physicalprocessorcount_spec.rb b/spec/unit/physicalprocessorcount_spec.rb
new file mode 100644
index 0000000..260788b
--- /dev/null
+++ b/spec/unit/physicalprocessorcount_spec.rb
@@ -0,0 +1,40 @@
+#!/usr/bin/env ruby
+
+require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')
+
+require 'facter'
+
+describe "Physical processor count facts" do
+    before do
+        Facter.loadfacts
+    end
+    before do
+        Facter.clear
+    end
+    it "should return one physical CPU" do
+        Facter.fact(:kernel).stubs(:value).returns("Linux")
+        File.stubs(:exists?).with('/sys/devices/system/cpu').returns(true)
+        Dir.stubs(:glob).with("/sys/devices/system/cpu/cpu*/topology/physical_package_id").returns("/sys/devices/system/cpu/cpu0/topology/physical_package_id")
+        Facter::Util::Resolution.stubs(:exec).with("cat /sys/devices/system/cpu/cpu0/topology/physical_package_id").returns("0")
+
+        Facter.fact(:physicalprocessorcount).value.should == 1
+    end
+
+    it "should return four physical CPUs" do
+        Facter.fact(:kernel).stubs(:value).returns("Linux")
+        File.stubs(:exists?).with('/sys/devices/system/cpu').returns(true)
+        Dir.stubs(:glob).with("/sys/devices/system/cpu/cpu*/topology/physical_package_id").returns(%w{
+          /sys/devices/system/cpu/cpu0/topology/physical_package_id
+          /sys/devices/system/cpu/cpu1/topology/physical_package_id
+          /sys/devices/system/cpu/cpu2/topology/physical_package_id
+          /sys/devices/system/cpu/cpu3/topology/physical_package_id
+        })
+
+        Facter::Util::Resolution.stubs(:exec).with("cat /sys/devices/system/cpu/cpu0/topology/physical_package_id").returns("0")
+        Facter::Util::Resolution.stubs(:exec).with("cat /sys/devices/system/cpu/cpu1/topology/physical_package_id").returns("1")
+        Facter::Util::Resolution.stubs(:exec).with("cat /sys/devices/system/cpu/cpu2/topology/physical_package_id").returns("2")
+        Facter::Util::Resolution.stubs(:exec).with("cat /sys/devices/system/cpu/cpu3/topology/physical_package_id").returns("3")
+
+        Facter.fact(:physicalprocessorcount).value.should == 4
+    end
+end