WIP: A couple of more ChannelMojo speedup ideas

third_party/mojo/src/mojo/edk/system/dispatcher.cc

 // Copyright 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.
 
 #include "mojo/edk/system/dispatcher.h"
 
 #include "base/logging.h"
 #include "mojo/edk/system/configuration.h"
 #include "mojo/edk/system/message_pipe_dispatcher.h"
 #include "mojo/edk/system/platform_handle_dispatcher.h"
@@ skipping 228 matching lines @@
   base::AutoLock locker(lock_);
   if (is_closed_) {
     if (handle_signals_state)
       *handle_signals_state = HandleSignalsState();
     return;
   }
 
   RemoveAwakableImplNoLock(awakable, handle_signals_state);
 }
 
+MojoResult Dispatcher::SetAsyncMessageCallback(
+    const AsyncMessageCallback& callback) {
+  base::AutoLock locker(lock_);
+  return SetAsyncMessageCallbackImplNoLock(callback);
+}
+
 Dispatcher::Dispatcher() : is_closed_(false) {
 }
 
 Dispatcher::~Dispatcher() {
   // Make sure that |Close()| was called.
   DCHECK(is_closed_);
 }
 
 void Dispatcher::CancelAllAwakablesNoLock() {
   lock_.AssertAcquired();
@@ skipping 129 matching lines @@
 void Dispatcher::RemoveAwakableImplNoLock(Awakable* /*awakable*/,
                                           HandleSignalsState* signals_state) {
   lock_.AssertAcquired();
   DCHECK(!is_closed_);
   // By default, waiting isn't supported. Only dispatchers that can be waited on
   // will do something nontrivial.
   if (signals_state)
     *signals_state = HandleSignalsState();
 }
 
+MojoResult Dispatcher::SetAsyncMessageCallbackImplNoLock(
+    const AsyncMessageCallback& callback) {
+  lock_.AssertAcquired();
+  NOTREACHED();
+  return MOJO_RESULT_INTERNAL;
+}
+
 void Dispatcher::StartSerializeImplNoLock(Channel* /*channel*/,
                                           size_t* max_size,
                                           size_t* max_platform_handles) {
   DCHECK(HasOneRef());  // Only one ref => no need to take the lock.
   DCHECK(!is_closed_);
   *max_size = 0;
   *max_platform_handles = 0;
 }
 
 bool Dispatcher::EndSerializeAndCloseImplNoLock(
@@ skipping 75 matching lines @@
 // DispatcherTransport ---------------------------------------------------------
 
 void DispatcherTransport::End() {
   DCHECK(dispatcher_);
   dispatcher_->lock_.Release();
   dispatcher_ = nullptr;
 }
 
 }  // namespace system
 }  // namespace mojo