Split GpuProcessHost into GpuProcessHostUIShim, which runs on the UI...

chrome/renderer/render_thread.cc

 // Copyright (c) 2010 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.
 
 #include "chrome/renderer/render_thread.h"
 
 #include <v8.h>
 
 #include <algorithm>
 #include <limits>
@@ skipping 669 matching lines @@
     return;
 
   std::set<std::string> active_extensions;
   user_script_slave_->GetActiveExtensions(&active_extensions);
   ExtensionProcessBindings::GetActiveExtensions(&active_extensions);
   child_process_logging::SetActiveExtensions(active_extensions);
 }
 
 void RenderThread::EstablishGpuChannel() {
   if (gpu_channel_.get()) {
-    // Do nothing if we are already establishing GPU channel.
-    if (gpu_channel_->state() == GpuChannelHost::UNCONNECTED)
+    // Do nothing if we already have a GPU channel or are already
+    // establishing one.
+    if (gpu_channel_->state() == GpuChannelHost::UNCONNECTED ||
+        gpu_channel_->state() == GpuChannelHost::CONNECTED)
       return;
 
     // Recreate the channel if it has been lost.
     if (gpu_channel_->state() == GpuChannelHost::LOST)
       gpu_channel_ = NULL;
   }
 
   if (!gpu_channel_.get())
     gpu_channel_ = new GpuChannelHost;
 
   // Ask the browser for the channel name.
   Send(new ViewHostMsg_EstablishGpuChannel());
 }
 
 GpuChannelHost* RenderThread::EstablishGpuChannelSync() {
-  EstablishGpuChannel();
-  Send(new ViewHostMsg_SynchronizeGpu());
+  // We may need to retry the connection establishment if an existing
+  // connection has gone bad, which will not be detected in
+  // EstablishGpuChannel since we do not send duplicate
+  // ViewHostMsg_EstablishGpuChannel messages -- doing so breaks the
+  // preexisting connection in bad ways.
+  bool retry = true;
+  for (int i = 0; i < 2 && retry; ++i) {
+    EstablishGpuChannel();
+    retry = !Send(new ViewHostMsg_SynchronizeGpu());
+  }
   // TODO(kbr): the GPU channel is still in the unconnected state at this point.
   // Need to figure out whether it is really safe to return it.
   return gpu_channel_.get();
 }
 
 GpuChannelHost* RenderThread::GetGpuChannel() {
   if (!gpu_channel_.get())
     return NULL;
 
   if (gpu_channel_->state() != GpuChannelHost::CONNECTED)
@@ skipping 272 matching lines @@
 #endif
 
   if (channel_handle.name.size() != 0) {
     // Connect to the GPU process if a channel name was received.
     gpu_channel_->Connect(channel_handle.name);
   } else {
     // Otherwise cancel the connection.
     gpu_channel_ = NULL;
   }
 }