Expose GPU information to Telemetry.

tools/telemetry/telemetry/core/chrome/system_info_backend.py

Index: tools/telemetry/telemetry/core/chrome/system_info_backend.py
diff --git a/tools/telemetry/telemetry/core/chrome/system_info_backend.py b/tools/telemetry/telemetry/core/chrome/system_info_backend.py
new file mode 100644
index 0000000000000000000000000000000000000000..141fe5c56bff96fdbdcc05c6fd7c96fb808dd014
--- /dev/null
+++ b/tools/telemetry/telemetry/core/chrome/system_info_backend.py
@@ -0,0 +1,58 @@
+# Copyright (c) 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import json
+import logging
+import socket
+
+
+from telemetry.core import system_info
+from telemetry.core.chrome import websocket
+from telemetry.core.chrome import camel_case_converter as camel_case
+
+
+class SystemInfoBackend(object):

[nduca, 2013/08/14 19:53:36]

hmm looks like most of this code is just to establish/comm with the browser
channel. maybe we can move that to the browser backend direclty, and have
methods like _SyncBrowserRequest(), and _CloseBrowserWebSocket() on it, and have
this and the tracing backend just call up to there.

[Ken Russell (switch to Gerrit), 2013/08/14 22:47:57]

The tracing backend requires its own websocket connection to the browser because
it uses it in multiple threads. The best that could be done would be to refactor
common code between tracing_backend.py and system_info_backend.py into a base
class.

+  def __init__(self, devtools_port):
+    debugger_url = 'ws://localhost:%i/devtools/browser' % devtools_port
+    self._socket = websocket.create_connection(debugger_url)
+    self._next_request_id = 0
+    self._cur_socket_timeout = 0
+    self._thread = None
+    self._tracing_data = []
+
+  def GetSystemInfo(self, timeout=10):
+    req = {'method': 'SystemInfo.getInfo'}
+    self._SyncRequest(req, timeout)
+    while self._socket:
+      try:
+        data = self._socket.recv()
+        if not data:
+          break
+        res = json.loads(data)
+        if 'error' in res:
+          return None
+        logging.debug('got [%s]', data)
+        return system_info.SystemInfo.FromDict(
+            camel_case.CamelCaseConverter.FromCamelCase(res['result']))
+      except (socket.error, websocket.WebSocketException):
+        logging.warning('Timeout waiting for system info; this is unusual.')
+    return None
+
+  def Close(self):
+    if self._socket:
+      self._socket.close()
+      self._socket = None
+
+  def _SyncRequest(self, req, timeout=10):
+    self._SetTimeout(timeout)
+    req['id'] = self._next_request_id
+    self._next_request_id += 1
+    data = json.dumps(req)
+    logging.debug('will send [%s]', data)
+    self._socket.send(data)
+
+  def _SetTimeout(self, timeout):
+    if self._cur_socket_timeout != timeout:
+      self._socket.settimeout(timeout)
+      self._cur_socket_timeout = timeout