NUMA topology discovering

Implements: blueprint support-numa-cpu-pinning
Depends-On: Id91c479f74d4e4945a6a1340e3f73a8789961b66
Change-Id: I7ef4fdd6a1e5501a47090badc38df8992595bd0b

agent

@@ -31,6 +31,8 @@ require 'timeout'
 require 'uri'
 # TODO(vsharshov): replace below lines by this string after excluding Ruby 1.8
 require 'pathname'
+require 'rexml/document'
+include REXML
 
 unless Process.euid == 0
   puts "You must be root"
@@ -147,6 +149,7 @@ class NodeAgent
     @api_url = "#{scheme}://#{@api_ip}:#{api_port}/api"
     @logger.info("API URL is #{@api_url}")
     @os = ohai_system_info
+    @numa_topology = get_numa_topology
   end
 
   def get_scheme_and_port
@@ -276,6 +279,7 @@ class NodeAgent
       :disks => [],
       :memory => (_dmi_memory or _ohai_memory),
       :pci_devices => _get_pci_dev_list,
+      :numa_topology => @numa_topology,
     }
 
     admin_mac = (_master_ip_and_mac[:mac] or @os[:macaddress]) rescue nil
@@ -806,6 +810,52 @@ class NodeAgent
     @logger.warn("Can't get data from lshw. Reason: #{e.message}")
   end
 
+  def get_numa_topology
+    # Output EXAMPLE:
+    # <distances nbobjs="2" relative_depth="1" latency_base="10.000000">
+    #   <latency value="1.000000"/>
+    #   <latency value="2.100000"/>
+    #   <latency value="2.100000"/>
+    #   <latency value="1.000000"/>
+    # </distances>
+    # <object type="NUMANode" os_index="0" cpuset="0x3ff003ff" complete_cpuset="0x3ff003ff" online_cpuset="0x3ff003ff" allowed_cpuset="0x3ff003ff" nodeset="0x00000001" complete_nodeset="0x00000001" allowed_nodeset="0x00000001" local_memory="67452473344">
+    #   <page_type size="4096" count="14370737"/>
+    #   <page_type size="1073741824" count="8"/>
+    doc = Document.new `lstopo --no-caches --of xml`
+
+    topology = {:numa_nodes => [], :supported_hugepages => supported_hugepages, :distances => nil}
+
+    doc.elements.each('/topology/object/distances/') do |dist|
+      topology[:distances] = dist.elements.collect{|v| v.attributes['value']}
+        .each_slice(dist.attributes['nbobjs'].to_i).to_a
+    end
+
+    numa_node = "/topology/object/object[@type='NUMANode']"
+    element = doc.elements[numa_node] ? numa_node : "/topology/object[@type='Machine']"
+
+    doc.elements.each(element) do |numa|
+
+      struct = {:id=> nil, :cpus => [], :memory => nil}
+      struct[:id] = numa.attributes['os_index'].to_i
+      struct[:memory] = numa.attributes['local_memory'].to_i
+
+      numa.elements.each("object/object/object[@type='PU']") do |pu|
+        struct[:cpus] << pu.attributes['os_index'].to_i
+      end
+      topology[:numa_nodes] << struct
+    end
+    topology
+  rescue e
+    logger.error "Something went wrong with parsing lstopo: #{e.backtrace}"
+    nil
+  end
+
+  def supported_hugepages
+      return [2048, 1048576] if @os[:cpu]['0']['flags'].include?('pdpe1gb')
+      return [2048] if @os[:cpu]['0']['flags'].include?('pse')
+      []
+  end
+
   def update_state
     @node_state = nil
     if File.exist?("/etc/nailgun_systemtype")