content/child/child_thread_impl.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/child/child_thread_impl.h"
   6
   7 #include <signal.h>
   8
   9 #include <string>
  10
  11 #include "base/allocator/allocator_extension.h"
  12 #include "base/base_switches.h"
  13 #include "base/basictypes.h"
  14 #include "base/command_line.h"
  15 #include "base/debug/leak_annotations.h"
  16 #include "base/debug/profiler.h"
  17 #include "base/lazy_instance.h"
  18 #include "base/location.h"
  19 #include "base/logging.h"
  20 #include "base/message_loop/timer_slack.h"
  21 #include "base/metrics/field_trial.h"
  22 #include "base/process/process.h"
  23 #include "base/process/process_handle.h"
  24 #include "base/single_thread_task_runner.h"
  25 #include "base/strings/string_number_conversions.h"
  26 #include "base/strings/string_util.h"
  27 #include "base/synchronization/condition_variable.h"
  28 #include "base/synchronization/lock.h"
  29 #include "base/thread_task_runner_handle.h"
  30 #include "base/threading/thread_local.h"
  31 #include "base/trace_event/memory_dump_manager.h"
  32 #include "base/tracked_objects.h"
  33 #include "components/tracing/child_trace_message_filter.h"
  34 #include "content/child/bluetooth/bluetooth_message_filter.h"
  35 #include "content/child/child_discardable_shared_memory_manager.h"
  36 #include "content/child/child_gpu_memory_buffer_manager.h"
  37 #include "content/child/child_histogram_message_filter.h"
  38 #include "content/child/child_process.h"
  39 #include "content/child/child_resource_message_filter.h"
  40 #include "content/child/child_shared_bitmap_manager.h"
  41 #include "content/child/fileapi/file_system_dispatcher.h"
  42 #include "content/child/fileapi/webfilesystem_impl.h"
  43 #include "content/child/geofencing/geofencing_message_filter.h"
  44 #include "content/child/mojo/mojo_application.h"
  45 #include "content/child/navigator_connect/navigator_connect_dispatcher.h"
  46 #include "content/child/notifications/notification_dispatcher.h"
  47 #include "content/child/power_monitor_broadcast_source.h"
  48 #include "content/child/push_messaging/push_dispatcher.h"
  49 #include "content/child/quota_dispatcher.h"
  50 #include "content/child/quota_message_filter.h"
  51 #include "content/child/resource_dispatcher.h"
  52 #include "content/child/service_worker/service_worker_message_filter.h"
  53 #include "content/child/thread_safe_sender.h"
  54 #include "content/child/websocket_dispatcher.h"
  55 #include "content/common/child_process_messages.h"
  56 #include "content/common/in_process_child_thread_params.h"
  57 #include "content/public/common/content_switches.h"
  58 #include "ipc/ipc_logging.h"
  59 #include "ipc/ipc_switches.h"
  60 #include "ipc/ipc_sync_channel.h"
  61 #include "ipc/ipc_sync_message_filter.h"
  62 #include "ipc/mojo/ipc_channel_mojo.h"
  63
  64 #if defined(OS_ANDROID)
  65 #include "base/thread_task_runner_handle.h"
  66 #endif
  67
  68 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED)
  69 #include "third_party/tcmalloc/chromium/src/gperftools/heap-profiler.h"
  70 #endif
  71
  72 using tracked_objects::ThreadData;
  73
  74 namespace content {
  75 namespace {
  76
  77 // How long to wait for a connection to the browser process before giving up.
  78 const int kConnectionTimeoutS = 15;
  79
  80 base::LazyInstance<base::ThreadLocalPointer<ChildThreadImpl> > g_lazy_tls =
  81     LAZY_INSTANCE_INITIALIZER;
  82
  83 // This isn't needed on Windows because there the sandbox's job object
  84 // terminates child processes automatically. For unsandboxed processes (i.e.
  85 // plugins), PluginThread has EnsureTerminateMessageFilter.
  86 #if defined(OS_POSIX)
  87
  88 #if defined(ADDRESS_SANITIZER) || defined(LEAK_SANITIZER) || \
  89     defined(MEMORY_SANITIZER) || defined(THREAD_SANITIZER) || \
  90     defined(UNDEFINED_SANITIZER)
  91 // A thread delegate that waits for |duration| and then exits the process with
  92 // _exit(0).
  93 class WaitAndExitDelegate : public base::PlatformThread::Delegate {
  94  public:
  95   explicit WaitAndExitDelegate(base::TimeDelta duration)
  96       : duration_(duration) {}
  97
  98   void ThreadMain() override {
  99     base::PlatformThread::Sleep(duration_);
 100     _exit(0);
 101   }
 102
 103  private:
 104   const base::TimeDelta duration_;
 105   DISALLOW_COPY_AND_ASSIGN(WaitAndExitDelegate);
 106 };
 107
 108 bool CreateWaitAndExitThread(base::TimeDelta duration) {
 109   scoped_ptr<WaitAndExitDelegate> delegate(new WaitAndExitDelegate(duration));
 110
 111   const bool thread_created =
 112       base::PlatformThread::CreateNonJoinable(0, delegate.get());
 113   if (!thread_created)
 114     return false;
 115
 116   // A non joinable thread has been created. The thread will either terminate
 117   // the process or will be terminated by the process. Therefore, keep the
 118   // delegate object alive for the lifetime of the process.
 119   WaitAndExitDelegate* leaking_delegate = delegate.release();
 120   ANNOTATE_LEAKING_OBJECT_PTR(leaking_delegate);
 121   ignore_result(leaking_delegate);
 122   return true;
 123 }
 124 #endif
 125
 126 class SuicideOnChannelErrorFilter : public IPC::MessageFilter {
 127  public:
 128   // IPC::MessageFilter
 129   void OnChannelError() override {
 130     // For renderer/worker processes:
 131     // On POSIX, at least, one can install an unload handler which loops
 132     // forever and leave behind a renderer process which eats 100% CPU forever.
 133     //
 134     // This is because the terminate signals (ViewMsg_ShouldClose and the error
 135     // from the IPC sender) are routed to the main message loop but never
 136     // processed (because that message loop is stuck in V8).
 137     //
 138     // One could make the browser SIGKILL the renderers, but that leaves open a
 139     // large window where a browser failure (or a user, manually terminating
 140     // the browser because "it's stuck") will leave behind a process eating all
 141     // the CPU.
 142     //
 143     // So, we install a filter on the sender so that we can process this event
 144     // here and kill the process.
 145     base::debug::StopProfiling();
 146 #if defined(ADDRESS_SANITIZER) || defined(LEAK_SANITIZER) || \
 147     defined(MEMORY_SANITIZER) || defined(THREAD_SANITIZER) || \
 148     defined(UNDEFINED_SANITIZER)
 149     // Some sanitizer tools rely on exit handlers (e.g. to run leak detection,
 150     // or dump code coverage data to disk). Instead of exiting the process
 151     // immediately, we give it 60 seconds to run exit handlers.
 152     CHECK(CreateWaitAndExitThread(base::TimeDelta::FromSeconds(60)));
 153 #if defined(LEAK_SANITIZER)
 154     // Invoke LeakSanitizer early to avoid detecting shutdown-only leaks. If
 155     // leaks are found, the process will exit here.
 156     __lsan_do_leak_check();
 157 #endif
 158 #else
 159     _exit(0);
 160 #endif
 161   }
 162
 163  protected:
 164   ~SuicideOnChannelErrorFilter() override {}
 165 };
 166
 167 #endif  // OS(POSIX)
 168
 169 #if defined(OS_ANDROID)
 170 // A class that allows for triggering a clean shutdown from another
 171 // thread through draining the main thread's msg loop.
 172 class QuitClosure {
 173  public:
 174   QuitClosure();
 175   ~QuitClosure();
 176
 177   void BindToMainThread();
 178   void PostQuitFromNonMainThread();
 179
 180  private:
 181   static void PostClosure(
 182       const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
 183       base::Closure closure);
 184
 185   base::Lock lock_;
 186   base::ConditionVariable cond_var_;
 187   base::Closure closure_;
 188 };
 189
 190 QuitClosure::QuitClosure() : cond_var_(&lock_) {
 191 }
 192
 193 QuitClosure::~QuitClosure() {
 194 }
 195
 196 void QuitClosure::PostClosure(
 197     const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
 198     base::Closure closure) {
 199   task_runner->PostTask(FROM_HERE, closure);
 200 }
 201
 202 void QuitClosure::BindToMainThread() {
 203   base::AutoLock lock(lock_);
 204   scoped_refptr<base::SingleThreadTaskRunner> task_runner(
 205       base::ThreadTaskRunnerHandle::Get());
 206   base::Closure quit_closure =
 207       base::MessageLoop::current()->QuitWhenIdleClosure();
 208   closure_ = base::Bind(&QuitClosure::PostClosure, task_runner, quit_closure);
 209   cond_var_.Signal();
 210 }
 211
 212 void QuitClosure::PostQuitFromNonMainThread() {
 213   base::AutoLock lock(lock_);
 214   while (closure_.is_null())
 215     cond_var_.Wait();
 216
 217   closure_.Run();
 218 }
 219
 220 base::LazyInstance<QuitClosure> g_quit_closure = LAZY_INSTANCE_INITIALIZER;
 221 #endif
 222
 223 }  // namespace
 224
 225 ChildThread* ChildThread::Get() {
 226   return ChildThreadImpl::current();
 227 }
 228
 229 ChildThreadImpl::Options::Options()
 230     : channel_name(base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
 231           switches::kProcessChannelID)),
 232       use_mojo_channel(false) {
 233 }
 234
 235 ChildThreadImpl::Options::~Options() {
 236 }
 237
 238 ChildThreadImpl::Options::Builder::Builder() {
 239 }
 240
 241 ChildThreadImpl::Options::Builder&
 242 ChildThreadImpl::Options::Builder::InBrowserProcess(
 243     const InProcessChildThreadParams& params) {
 244   options_.browser_process_io_runner = params.io_runner();
 245   options_.channel_name = params.channel_name();
 246   return *this;
 247 }
 248
 249 ChildThreadImpl::Options::Builder&
 250 ChildThreadImpl::Options::Builder::UseMojoChannel(bool use_mojo_channel) {
 251   options_.use_mojo_channel = use_mojo_channel;
 252   return *this;
 253 }
 254
 255 ChildThreadImpl::Options::Builder&
 256 ChildThreadImpl::Options::Builder::WithChannelName(
 257     const std::string& channel_name) {
 258   options_.channel_name = channel_name;
 259   return *this;
 260 }
 261
 262 ChildThreadImpl::Options::Builder&
 263 ChildThreadImpl::Options::Builder::AddStartupFilter(
 264     IPC::MessageFilter* filter) {
 265   options_.startup_filters.push_back(filter);
 266   return *this;
 267 }
 268
 269 ChildThreadImpl::Options ChildThreadImpl::Options::Builder::Build() {
 270   return options_;
 271 }
 272
 273 ChildThreadImpl::ChildThreadMessageRouter::ChildThreadMessageRouter(
 274     IPC::Sender* sender)
 275     : sender_(sender) {}
 276
 277 bool ChildThreadImpl::ChildThreadMessageRouter::Send(IPC::Message* msg) {
 278   return sender_->Send(msg);
 279 }
 280
 281 ChildThreadImpl::ChildThreadImpl()
 282     : router_(this),
 283       channel_connected_factory_(this) {
 284   Init(Options::Builder().Build());
 285 }
 286
 287 ChildThreadImpl::ChildThreadImpl(const Options& options)
 288     : router_(this),
 289       browser_process_io_runner_(options.browser_process_io_runner),
 290       channel_connected_factory_(this) {
 291   Init(options);
 292 }
 293
 294 scoped_refptr<base::SequencedTaskRunner> ChildThreadImpl::GetIOTaskRunner() {
 295   if (IsInBrowserProcess())
 296     return browser_process_io_runner_;
 297   return ChildProcess::current()->io_task_runner();
 298 }
 299
 300 void ChildThreadImpl::ConnectChannel(bool use_mojo_channel) {
 301   bool create_pipe_now = true;
 302   if (use_mojo_channel) {
 303     VLOG(1) << "Mojo is enabled on child";
 304     scoped_refptr<base::SequencedTaskRunner> io_task_runner = GetIOTaskRunner();
 305     DCHECK(io_task_runner);
 306     channel_->Init(IPC::ChannelMojo::CreateClientFactory(
 307                        nullptr, io_task_runner, channel_name_),
 308                    create_pipe_now);
 309     return;
 310   }
 311
 312   VLOG(1) << "Mojo is disabled on child";
 313   channel_->Init(channel_name_, IPC::Channel::MODE_CLIENT, create_pipe_now);
 314 }
 315
 316 void ChildThreadImpl::Init(const Options& options) {
 317   channel_name_ = options.channel_name;
 318
 319   g_lazy_tls.Pointer()->Set(this);
 320   on_channel_error_called_ = false;
 321   message_loop_ = base::MessageLoop::current();
 322 #ifdef IPC_MESSAGE_LOG_ENABLED
 323   // We must make sure to instantiate the IPC Logger *before* we create the
 324   // channel, otherwise we can get a callback on the IO thread which creates
 325   // the logger, and the logger does not like being created on the IO thread.
 326   IPC::Logging::GetInstance();
 327 #endif
 328   channel_ =
 329       IPC::SyncChannel::Create(this, ChildProcess::current()->io_task_runner(),
 330                                ChildProcess::current()->GetShutDownEvent());
 331 #ifdef IPC_MESSAGE_LOG_ENABLED
 332   if (!IsInBrowserProcess())
 333     IPC::Logging::GetInstance()->SetIPCSender(this);
 334 #endif
 335
 336   mojo_application_.reset(new MojoApplication(GetIOTaskRunner()));
 337
 338   sync_message_filter_ =
 339       new IPC::SyncMessageFilter(ChildProcess::current()->GetShutDownEvent());
 340   thread_safe_sender_ = new ThreadSafeSender(
 341       message_loop_->task_runner(), sync_message_filter_.get());
 342
 343   resource_dispatcher_.reset(new ResourceDispatcher(
 344       this, message_loop()->task_runner()));
 345   websocket_dispatcher_.reset(new WebSocketDispatcher);
 346   file_system_dispatcher_.reset(new FileSystemDispatcher());
 347
 348   histogram_message_filter_ = new ChildHistogramMessageFilter();
 349   resource_message_filter_ =
 350       new ChildResourceMessageFilter(resource_dispatcher());
 351
 352   service_worker_message_filter_ =
 353       new ServiceWorkerMessageFilter(thread_safe_sender_.get());
 354
 355   quota_message_filter_ =
 356       new QuotaMessageFilter(thread_safe_sender_.get());
 357   quota_dispatcher_.reset(new QuotaDispatcher(thread_safe_sender_.get(),
 358                                               quota_message_filter_.get()));
 359   geofencing_message_filter_ =
 360       new GeofencingMessageFilter(thread_safe_sender_.get());
 361   bluetooth_message_filter_ =
 362       new BluetoothMessageFilter(thread_safe_sender_.get());
 363   notification_dispatcher_ =
 364       new NotificationDispatcher(thread_safe_sender_.get());
 365   push_dispatcher_ = new PushDispatcher(thread_safe_sender_.get());
 366   navigator_connect_dispatcher_ =
 367       new NavigatorConnectDispatcher(thread_safe_sender_.get());
 368
 369   channel_->AddFilter(histogram_message_filter_.get());
 370   channel_->AddFilter(sync_message_filter_.get());
 371   channel_->AddFilter(resource_message_filter_.get());
 372   channel_->AddFilter(quota_message_filter_->GetFilter());
 373   channel_->AddFilter(notification_dispatcher_->GetFilter());
 374   channel_->AddFilter(push_dispatcher_->GetFilter());
 375   channel_->AddFilter(service_worker_message_filter_->GetFilter());
 376   channel_->AddFilter(geofencing_message_filter_->GetFilter());
 377   channel_->AddFilter(bluetooth_message_filter_->GetFilter());
 378   channel_->AddFilter(navigator_connect_dispatcher_->GetFilter());
 379
 380   if (!IsInBrowserProcess()) {
 381     // In single process mode, browser-side tracing will cover the whole
 382     // process including renderers.
 383     channel_->AddFilter(new tracing::ChildTraceMessageFilter(
 384         ChildProcess::current()->io_task_runner()));
 385   }
 386
 387   // In single process mode we may already have a power monitor
 388   if (!base::PowerMonitor::Get()) {
 389     scoped_ptr<PowerMonitorBroadcastSource> power_monitor_source(
 390       new PowerMonitorBroadcastSource());
 391     channel_->AddFilter(power_monitor_source->GetMessageFilter());
 392
 393     power_monitor_.reset(new base::PowerMonitor(
 394         power_monitor_source.Pass()));
 395   }
 396
 397 #if defined(OS_POSIX)
 398   // Check that --process-type is specified so we don't do this in unit tests
 399   // and single-process mode.
 400   if (base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kProcessType))
 401     channel_->AddFilter(new SuicideOnChannelErrorFilter());
 402 #endif
 403
 404   // Add filters passed here via options.
 405   for (auto startup_filter : options.startup_filters) {
 406     channel_->AddFilter(startup_filter);
 407   }
 408
 409   ConnectChannel(options.use_mojo_channel);
 410
 411   int connection_timeout = kConnectionTimeoutS;
 412   std::string connection_override =
 413       base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
 414           switches::kIPCConnectionTimeout);
 415   if (!connection_override.empty()) {
 416     int temp;
 417     if (base::StringToInt(connection_override, &temp))
 418       connection_timeout = temp;
 419   }
 420
 421   message_loop_->task_runner()->PostDelayedTask(
 422       FROM_HERE, base::Bind(&ChildThreadImpl::EnsureConnected,
 423                             channel_connected_factory_.GetWeakPtr()),
 424       base::TimeDelta::FromSeconds(connection_timeout));
 425
 426 #if defined(OS_ANDROID)
 427   g_quit_closure.Get().BindToMainThread();
 428 #endif
 429
 430 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED)
 431   trace_memory_controller_.reset(new base::trace_event::TraceMemoryController(
 432       message_loop_->task_runner(), ::HeapProfilerWithPseudoStackStart,
 433       ::HeapProfilerStop, ::GetHeapProfile));
 434 #endif
 435
 436   base::trace_event::MemoryDumpManager::GetInstance()->Initialize();
 437
 438   shared_bitmap_manager_.reset(
 439       new ChildSharedBitmapManager(thread_safe_sender()));
 440
 441   gpu_memory_buffer_manager_.reset(
 442       new ChildGpuMemoryBufferManager(thread_safe_sender()));
 443
 444   discardable_shared_memory_manager_.reset(
 445       new ChildDiscardableSharedMemoryManager(thread_safe_sender()));
 446 }
 447
 448 ChildThreadImpl::~ChildThreadImpl() {
 449   // ChildDiscardableSharedMemoryManager has to be destroyed while
 450   // |thread_safe_sender_| is still valid.
 451   discardable_shared_memory_manager_.reset();
 452
 453 #ifdef IPC_MESSAGE_LOG_ENABLED
 454   IPC::Logging::GetInstance()->SetIPCSender(NULL);
 455 #endif
 456
 457   channel_->RemoveFilter(histogram_message_filter_.get());
 458   channel_->RemoveFilter(sync_message_filter_.get());
 459
 460   // The ChannelProxy object caches a pointer to the IPC thread, so need to
 461   // reset it as it's not guaranteed to outlive this object.
 462   // NOTE: this also has the side-effect of not closing the main IPC channel to
 463   // the browser process.  This is needed because this is the signal that the
 464   // browser uses to know that this process has died, so we need it to be alive
 465   // until this process is shut down, and the OS closes the handle
 466   // automatically.  We used to watch the object handle on Windows to do this,
 467   // but it wasn't possible to do so on POSIX.
 468   channel_->ClearIPCTaskRunner();
 469   g_lazy_tls.Pointer()->Set(NULL);
 470 }
 471
 472 void ChildThreadImpl::Shutdown() {
 473   // Delete objects that hold references to blink so derived classes can
 474   // safely shutdown blink in their Shutdown implementation.
 475   file_system_dispatcher_.reset();
 476   quota_dispatcher_.reset();
 477   WebFileSystemImpl::DeleteThreadSpecificInstance();
 478 }
 479
 480 void ChildThreadImpl::OnChannelConnected(int32 peer_pid) {
 481   channel_connected_factory_.InvalidateWeakPtrs();
 482 }
 483
 484 void ChildThreadImpl::OnChannelError() {
 485   set_on_channel_error_called(true);
 486   base::MessageLoop::current()->Quit();
 487 }
 488
 489 bool ChildThreadImpl::Send(IPC::Message* msg) {
 490   DCHECK(base::MessageLoop::current() == message_loop());
 491   if (!channel_) {
 492     delete msg;
 493     return false;
 494   }
 495
 496   return channel_->Send(msg);
 497 }
 498
 499 #if defined(OS_WIN)
 500 void ChildThreadImpl::PreCacheFont(const LOGFONT& log_font) {
 501   Send(new ChildProcessHostMsg_PreCacheFont(log_font));
 502 }
 503
 504 void ChildThreadImpl::ReleaseCachedFonts() {
 505   Send(new ChildProcessHostMsg_ReleaseCachedFonts());
 506 }
 507 #endif
 508
 509 MessageRouter* ChildThreadImpl::GetRouter() {
 510   DCHECK(base::MessageLoop::current() == message_loop());
 511   return &router_;
 512 }
 513
 514 scoped_ptr<base::SharedMemory> ChildThreadImpl::AllocateSharedMemory(
 515     size_t buf_size) {
 516   DCHECK(base::MessageLoop::current() == message_loop());
 517   return AllocateSharedMemory(buf_size, this);
 518 }
 519
 520 // static
 521 scoped_ptr<base::SharedMemory> ChildThreadImpl::AllocateSharedMemory(
 522     size_t buf_size,
 523     IPC::Sender* sender) {
 524   scoped_ptr<base::SharedMemory> shared_buf;
 525 #if defined(OS_WIN)
 526   shared_buf.reset(new base::SharedMemory);
 527   if (!shared_buf->CreateAnonymous(buf_size)) {
 528     NOTREACHED();
 529     return NULL;
 530   }
 531 #else
 532   // On POSIX, we need to ask the browser to create the shared memory for us,
 533   // since this is blocked by the sandbox.
 534   base::SharedMemoryHandle shared_mem_handle;
 535   if (sender->Send(new ChildProcessHostMsg_SyncAllocateSharedMemory(
 536                            buf_size, &shared_mem_handle))) {
 537     if (base::SharedMemory::IsHandleValid(shared_mem_handle)) {
 538       shared_buf.reset(new base::SharedMemory(shared_mem_handle, false));
 539     } else {
 540       NOTREACHED() << "Browser failed to allocate shared memory";
 541       return NULL;
 542     }
 543   } else {
 544     NOTREACHED() << "Browser allocation request message failed";
 545     return NULL;
 546   }
 547 #endif
 548   return shared_buf;
 549 }
 550
 551 bool ChildThreadImpl::OnMessageReceived(const IPC::Message& msg) {
 552   if (mojo_application_->OnMessageReceived(msg))
 553     return true;
 554
 555   // Resource responses are sent to the resource dispatcher.
 556   if (resource_dispatcher_->OnMessageReceived(msg))
 557     return true;
 558   if (websocket_dispatcher_->OnMessageReceived(msg))
 559     return true;
 560   if (file_system_dispatcher_->OnMessageReceived(msg))
 561     return true;
 562
 563   bool handled = true;
 564   IPC_BEGIN_MESSAGE_MAP(ChildThreadImpl, msg)
 565     IPC_MESSAGE_HANDLER(ChildProcessMsg_Shutdown, OnShutdown)
 566 #if defined(IPC_MESSAGE_LOG_ENABLED)
 567     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetIPCLoggingEnabled,
 568                         OnSetIPCLoggingEnabled)
 569 #endif
 570     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetProfilerStatus,
 571                         OnSetProfilerStatus)
 572     IPC_MESSAGE_HANDLER(ChildProcessMsg_GetChildProfilerData,
 573                         OnGetChildProfilerData)
 574     IPC_MESSAGE_HANDLER(ChildProcessMsg_ProfilingPhaseCompleted,
 575                         OnProfilingPhaseCompleted)
 576     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetProcessBackgrounded,
 577                         OnProcessBackgrounded)
 578 #if defined(USE_TCMALLOC)
 579     IPC_MESSAGE_HANDLER(ChildProcessMsg_GetTcmallocStats, OnGetTcmallocStats)
 580 #endif
 581     IPC_MESSAGE_UNHANDLED(handled = false)
 582   IPC_END_MESSAGE_MAP()
 583
 584   if (handled)
 585     return true;
 586
 587   if (msg.routing_id() == MSG_ROUTING_CONTROL)
 588     return OnControlMessageReceived(msg);
 589
 590   return router_.OnMessageReceived(msg);
 591 }
 592
 593 bool ChildThreadImpl::OnControlMessageReceived(const IPC::Message& msg) {
 594   return false;
 595 }
 596
 597 void ChildThreadImpl::OnShutdown() {
 598   base::MessageLoop::current()->Quit();
 599 }
 600
 601 #if defined(IPC_MESSAGE_LOG_ENABLED)
 602 void ChildThreadImpl::OnSetIPCLoggingEnabled(bool enable) {
 603   if (enable)
 604     IPC::Logging::GetInstance()->Enable();
 605   else
 606     IPC::Logging::GetInstance()->Disable();
 607 }
 608 #endif  //  IPC_MESSAGE_LOG_ENABLED
 609
 610 void ChildThreadImpl::OnSetProfilerStatus(ThreadData::Status status) {
 611   ThreadData::InitializeAndSetTrackingStatus(status);
 612 }
 613
 614 void ChildThreadImpl::OnGetChildProfilerData(int sequence_number,
 615                                              int current_profiling_phase) {
 616   tracked_objects::ProcessDataSnapshot process_data;
 617   ThreadData::Snapshot(current_profiling_phase, &process_data);
 618
 619   Send(
 620       new ChildProcessHostMsg_ChildProfilerData(sequence_number, process_data));
 621 }
 622
 623 void ChildThreadImpl::OnProfilingPhaseCompleted(int profiling_phase) {
 624   ThreadData::OnProfilingPhaseCompleted(profiling_phase);
 625 }
 626
 627 #if defined(USE_TCMALLOC)
 628 void ChildThreadImpl::OnGetTcmallocStats() {
 629   std::string result;
 630   char buffer[1024 * 32];
 631   base::allocator::GetStats(buffer, sizeof(buffer));
 632   result.append(buffer);
 633   Send(new ChildProcessHostMsg_TcmallocStats(result));
 634 }
 635 #endif
 636
 637 ChildThreadImpl* ChildThreadImpl::current() {
 638   return g_lazy_tls.Pointer()->Get();
 639 }
 640
 641 #if defined(OS_ANDROID)
 642 // The method must NOT be called on the child thread itself.
 643 // It may block the child thread if so.
 644 void ChildThreadImpl::ShutdownThread() {
 645   DCHECK(!ChildThreadImpl::current()) <<
 646       "this method should NOT be called from child thread itself";
 647   g_quit_closure.Get().PostQuitFromNonMainThread();
 648 }
 649 #endif
 650
 651 void ChildThreadImpl::OnProcessFinalRelease() {
 652   if (on_channel_error_called_) {
 653     base::MessageLoop::current()->Quit();
 654     return;
 655   }
 656
 657   // The child process shutdown sequence is a request response based mechanism,
 658   // where we send out an initial feeler request to the child process host
 659   // instance in the browser to verify if it's ok to shutdown the child process.
 660   // The browser then sends back a response if it's ok to shutdown. This avoids
 661   // race conditions if the process refcount is 0 but there's an IPC message
 662   // inflight that would addref it.
 663   Send(new ChildProcessHostMsg_ShutdownRequest);
 664 }
 665
 666 void ChildThreadImpl::EnsureConnected() {
 667   VLOG(0) << "ChildThreadImpl::EnsureConnected()";
 668   base::Process::Current().Terminate(0, false);
 669 }
 670
 671 bool ChildThreadImpl::IsInBrowserProcess() const {
 672   return browser_process_io_runner_;
 673 }
 674
 675 void ChildThreadImpl::OnProcessBackgrounded(bool background) {
 676   // Set timer slack to maximum on main thread when in background.
 677   base::TimerSlack timer_slack = base::TIMER_SLACK_NONE;
 678   if (background)
 679     timer_slack = base::TIMER_SLACK_MAXIMUM;
 680   base::MessageLoop::current()->SetTimerSlack(timer_slack);
 681 }
 682
 683 }  // namespace content