GPU Channel's now maintain a global order number for each processed IPC.

content/common/gpu/gpu_channel_manager.cc

Index: content/common/gpu/gpu_channel_manager.cc
diff --git a/content/common/gpu/gpu_channel_manager.cc b/content/common/gpu/gpu_channel_manager.cc
index 1f027783eb02dc5b839f150f1181872dde49cfd8..9c37102d9ab6bc6bc75e0cfea4507dda83b8526c 100644
--- a/content/common/gpu/gpu_channel_manager.cc
+++ b/content/common/gpu/gpu_channel_manager.cc
@@ -39,6 +39,7 @@ GpuChannelManager::GpuChannelManager(
     : task_runner_(task_runner),
       io_task_runner_(io_task_runner),
       channel_(channel),
+      global_order_counter_(0),
       watchdog_(watchdog),
       shutdown_event_(shutdown_event),
       gpu_memory_manager_(
@@ -50,6 +51,7 @@ GpuChannelManager::GpuChannelManager(
       weak_factory_(this) {
   DCHECK(task_runner);
   DCHECK(io_task_runner);
+  io_thread_checker_.DetachFromThread();
 }
 
 GpuChannelManager::~GpuChannelManager() {
@@ -105,6 +107,11 @@ void GpuChannelManager::RemoveRoute(int32 routing_id) {
   router_.RemoveRoute(routing_id);
 }
 
+uint32_t GpuChannelManager::GenerateGlobalOrderNumber() {
+  DCHECK(io_thread_checker_.CalledOnValidThread());
+  return global_order_counter_++;
+}
+
 GpuChannel* GpuChannelManager::LookupChannel(int32 client_id) {
   const auto& it = gpu_channels_.find(client_id);
   return it != gpu_channels_.end() ? it->second : nullptr;
@@ -255,11 +262,12 @@ bool GpuChannelManager::HandleMessagesScheduled() {
   return false;
 }
 
-uint64 GpuChannelManager::MessagesProcessed() {
-  uint64 messages_processed = 0;
+uint32_t GpuChannelManager::ProcessedOrderNumber() {
+  uint32_t processed_order_num = 0;
   for (auto& kv : gpu_channels_)

[piman, 2015/08/31 23:15:04]

nit: needs brackets per style guide

[David Yen, 2015/09/01 02:01:52]

Done, although I was following the style in the below function :). I changed the
function below as well.

-    messages_processed += kv.second->messages_processed();
-  return messages_processed;
+    processed_order_num = std::max(processed_order_num,
+                                   kv.second->GetProcessedOrderNum());
+  return processed_order_num;
 }
 
 void GpuChannelManager::LoseAllContexts() {