Add multi-architecture support in telemetry.

tools/telemetry/telemetry/core/platform/linux_platform_backend.py

Index: tools/telemetry/telemetry/core/platform/linux_platform_backend.py
diff --git a/tools/telemetry/telemetry/core/platform/linux_platform_backend.py b/tools/telemetry/telemetry/core/platform/linux_platform_backend.py
index 4a24b147c99c7dc0a9892c925c2fe8598f667208..54fde65707b7e81da791bab67dc4d8b1a485da6b 100644
--- a/tools/telemetry/telemetry/core/platform/linux_platform_backend.py
+++ b/tools/telemetry/telemetry/core/platform/linux_platform_backend.py
@@ -4,6 +4,7 @@
 
 import logging
 import os
+import platform
 import subprocess
 import sys
 
@@ -44,6 +45,10 @@ class LinuxPlatformBackend(
   def HasBeenThermallyThrottled(self):
     raise NotImplementedError()
 
+  @decorators.Cache
+  def GetArchName(self):
+    return platform.machine()
+
   def GetOSName(self):
     return 'linux'
 
@@ -121,8 +126,10 @@ class LinuxPlatformBackend(
         ['lsmod'], stdout=subprocess.PIPE).communicate()[0]
 
   def _InstallIpfw(self):
-    ipfw_bin = support_binaries.FindPath('ipfw', self.GetOSName())
-    ipfw_mod = support_binaries.FindPath('ipfw_mod.ko', self.GetOSName())
+    ipfw_bin = support_binaries.FindPath(
+        'ipfw', self.GetArchName(), self.GetOSName())

[pasko, 2014/10/14 14:15:42]

I think Tony means that support_binaries should know which binary to get without
providing with the arch name. I am not sure how to do that in presence of both
host and target platforms. Tony, would you like a parameter like host=True/False
for this? Any other suggestions?

I am OK with either approach actually.

+    ipfw_mod = support_binaries.FindPath(
+        'ipfw_mod.ko', self.GetArchName(), self.GetOSName())
 
     try:
       changed = cloud_storage.GetIfChanged(
@@ -148,7 +155,8 @@ class LinuxPlatformBackend(
         'your kernel. See: http://info.iet.unipi.it/~luigi/dummynet/'
 
   def _InstallBinary(self, bin_name, fallback_package=None):
-    bin_path = support_binaries.FindPath(bin_name, self.GetOSName())
+    bin_path = support_binaries.FindPath(
+        bin_name, self.GetArchName(), self.GetOSName())
     if not bin_path:
       raise Exception('Could not find the binary package %s' % bin_name)
     os.environ['PATH'] += os.pathsep + os.path.dirname(bin_path)