src/content/child/child_thread.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.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/lazy_instance.h"
  17 #include "base/logging.h"
  18 #include "base/message_loop/message_loop.h"
  19 #include "base/process/kill.h"
  20 #include "base/process/process_handle.h"
  21 #include "base/strings/string_util.h"
  22 #include "base/synchronization/condition_variable.h"
  23 #include "base/synchronization/lock.h"
  24 #include "base/threading/thread_local.h"
  25 #include "base/tracked_objects.h"
  26 #include "components/tracing/child_trace_message_filter.h"
  27 #include "content/child/child_histogram_message_filter.h"
  28 #include "content/child/child_process.h"
  29 #include "content/child/child_resource_message_filter.h"
  30 #include "content/child/child_shared_bitmap_manager.h"
  31 #include "content/child/fileapi/file_system_dispatcher.h"
  32 #include "content/child/power_monitor_broadcast_source.h"
  33 #include "content/child/quota_dispatcher.h"
  34 #include "content/child/quota_message_filter.h"
  35 #include "content/child/resource_dispatcher.h"
  36 #include "content/child/service_worker/service_worker_dispatcher.h"
  37 #include "content/child/service_worker/service_worker_message_filter.h"
  38 #include "content/child/socket_stream_dispatcher.h"
  39 #include "content/child/thread_safe_sender.h"
  40 #include "content/child/websocket_dispatcher.h"
  41 #include "content/common/child_process_messages.h"
  42 #include "content/public/common/content_switches.h"
  43 #include "ipc/ipc_logging.h"
  44 #include "ipc/ipc_switches.h"
  45 #include "ipc/ipc_sync_channel.h"
  46 #include "ipc/ipc_sync_message_filter.h"
  47 #include "webkit/child/resource_loader_bridge.h"
  48
  49 #if defined(OS_WIN)
  50 #include "content/common/handle_enumerator_win.h"
  51 #endif
  52
  53 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED)
  54 #include "third_party/tcmalloc/chromium/src/gperftools/heap-profiler.h"
  55 #endif
  56
  57 using tracked_objects::ThreadData;
  58
  59 namespace content {
  60 namespace {
  61
  62 // How long to wait for a connection to the browser process before giving up.
  63 const int kConnectionTimeoutS = 15;
  64
  65 base::LazyInstance<base::ThreadLocalPointer<ChildThread> > g_lazy_tls =
  66     LAZY_INSTANCE_INITIALIZER;
  67
  68 // This isn't needed on Windows because there the sandbox's job object
  69 // terminates child processes automatically. For unsandboxed processes (i.e.
  70 // plugins), PluginThread has EnsureTerminateMessageFilter.
  71 #if defined(OS_POSIX)
  72
  73 // A thread delegate that waits for |duration| and then signals the process
  74 // with SIGALRM.
  75 class WaitAndExitDelegate : public base::PlatformThread::Delegate {
  76  public:
  77   explicit WaitAndExitDelegate(base::TimeDelta duration)
  78       : duration_(duration) {}
  79   virtual ~WaitAndExitDelegate() OVERRIDE {}
  80
  81   virtual void ThreadMain() OVERRIDE {
  82     base::PlatformThread::Sleep(duration_);
  83     // This used to be implemented with alarm(2). Make sure to not break
  84     // anything that requires the process being signaled.
  85     CHECK_EQ(0, raise(SIGALRM));
  86
  87     base::PlatformThread::Sleep((base::TimeDelta::FromSeconds(10)));
  88     // If something erroneously blocked SIGALRM, this will trigger.
  89     NOTREACHED();
  90     _exit(0);
  91   }
  92
  93  private:
  94   const base::TimeDelta duration_;
  95   DISALLOW_COPY_AND_ASSIGN(WaitAndExitDelegate);
  96 };
  97
  98 // This is similar to using alarm(2), except it will spawn a thread
  99 // which will sleep for |duration| before raising SIGALRM.
 100 bool CreateAlarmThread(base::TimeDelta duration) {
 101   scoped_ptr<WaitAndExitDelegate> delegate(new WaitAndExitDelegate(duration));
 102
 103   const bool thread_created = base::PlatformThread::CreateNonJoinable(
 104       0 /* stack_size */, delegate.get());
 105   if (!thread_created)
 106     return false;
 107
 108   // A non joinable thread has been created. The thread will either terminate
 109   // the process or will be terminated by the process. Therefore, keep the
 110   // delegate object alive for the lifetime of the process.
 111   WaitAndExitDelegate* leaking_delegate = delegate.release();
 112   ANNOTATE_LEAKING_OBJECT_PTR(leaking_delegate);
 113   ignore_result(leaking_delegate);
 114   return true;
 115 }
 116
 117 class SuicideOnChannelErrorFilter : public IPC::ChannelProxy::MessageFilter {
 118  public:
 119   // IPC::ChannelProxy::MessageFilter
 120   virtual void OnChannelError() OVERRIDE {
 121     // For renderer/worker processes:
 122     // On POSIX, at least, one can install an unload handler which loops
 123     // forever and leave behind a renderer process which eats 100% CPU forever.
 124     //
 125     // This is because the terminate signals (ViewMsg_ShouldClose and the error
 126     // from the IPC channel) are routed to the main message loop but never
 127     // processed (because that message loop is stuck in V8).
 128     //
 129     // One could make the browser SIGKILL the renderers, but that leaves open a
 130     // large window where a browser failure (or a user, manually terminating
 131     // the browser because "it's stuck") will leave behind a process eating all
 132     // the CPU.
 133     //
 134     // So, we install a filter on the channel so that we can process this event
 135     // here and kill the process.
 136     if (CommandLine::ForCurrentProcess()->
 137         HasSwitch(switches::kChildCleanExit)) {
 138       // If clean exit is requested, we want to kill this process after giving
 139       // it 60 seconds to run exit handlers. Exit handlers may including ones
 140       // that write profile data to disk (which happens under profile collection
 141       // mode).
 142       CHECK(CreateAlarmThread(base::TimeDelta::FromSeconds(60)));
 143 #if defined(LEAK_SANITIZER)
 144       // Invoke LeakSanitizer early to avoid detecting shutdown-only leaks. If
 145       // leaks are found, the process will exit here.
 146       __lsan_do_leak_check();
 147 #endif
 148     } else {
 149       _exit(0);
 150     }
 151   }
 152
 153  protected:
 154   virtual ~SuicideOnChannelErrorFilter() {}
 155 };
 156
 157 #endif  // OS(POSIX)
 158
 159 #if defined(OS_ANDROID)
 160 ChildThread* g_child_thread = NULL;
 161
 162 // A lock protects g_child_thread.
 163 base::LazyInstance<base::Lock> g_lazy_child_thread_lock =
 164     LAZY_INSTANCE_INITIALIZER;
 165
 166 // base::ConditionVariable has an explicit constructor that takes
 167 // a base::Lock pointer as parameter. The base::DefaultLazyInstanceTraits
 168 // doesn't handle the case. Thus, we need our own class here.
 169 struct CondVarLazyInstanceTraits {
 170   static const bool kRegisterOnExit = true;
 171 #ifndef NDEBUG
 172   static const bool kAllowedToAccessOnNonjoinableThread = false;
 173 #endif
 174
 175   static base::ConditionVariable* New(void* instance) {
 176     return new (instance) base::ConditionVariable(
 177         g_lazy_child_thread_lock.Pointer());
 178   }
 179   static void Delete(base::ConditionVariable* instance) {
 180     instance->~ConditionVariable();
 181   }
 182 };
 183
 184 // A condition variable that synchronize threads initializing and waiting
 185 // for g_child_thread.
 186 base::LazyInstance<base::ConditionVariable, CondVarLazyInstanceTraits>
 187     g_lazy_child_thread_cv = LAZY_INSTANCE_INITIALIZER;
 188
 189 void QuitMainThreadMessageLoop() {
 190   base::MessageLoop::current()->Quit();
 191 }
 192
 193 #endif
 194
 195 }  // namespace
 196
 197 ChildThread::ChildThreadMessageRouter::ChildThreadMessageRouter(
 198     IPC::Sender* sender)
 199     : sender_(sender) {}
 200
 201 bool ChildThread::ChildThreadMessageRouter::Send(IPC::Message* msg) {
 202   return sender_->Send(msg);
 203 }
 204
 205 ChildThread::ChildThread()
 206     : router_(this),
 207       channel_connected_factory_(this),
 208       in_browser_process_(false) {
 209   channel_name_ = CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
 210       switches::kProcessChannelID);
 211   Init();
 212 }
 213
 214 ChildThread::ChildThread(const std::string& channel_name)
 215     : channel_name_(channel_name),
 216       router_(this),
 217       channel_connected_factory_(this),
 218       in_browser_process_(true) {
 219   Init();
 220 }
 221
 222 void ChildThread::Init() {
 223   g_lazy_tls.Pointer()->Set(this);
 224   on_channel_error_called_ = false;
 225   message_loop_ = base::MessageLoop::current();
 226 #ifdef IPC_MESSAGE_LOG_ENABLED
 227   // We must make sure to instantiate the IPC Logger *before* we create the
 228   // channel, otherwise we can get a callback on the IO thread which creates
 229   // the logger, and the logger does not like being created on the IO thread.
 230   IPC::Logging::GetInstance();
 231 #endif
 232   channel_.reset(
 233       new IPC::SyncChannel(channel_name_,
 234                            IPC::Channel::MODE_CLIENT,
 235                            this,
 236                            ChildProcess::current()->io_message_loop_proxy(),
 237                            true,
 238                            ChildProcess::current()->GetShutDownEvent()));
 239 #ifdef IPC_MESSAGE_LOG_ENABLED
 240   if (!in_browser_process_)
 241     IPC::Logging::GetInstance()->SetIPCSender(this);
 242 #endif
 243
 244   sync_message_filter_ =
 245       new IPC::SyncMessageFilter(ChildProcess::current()->GetShutDownEvent());
 246   thread_safe_sender_ = new ThreadSafeSender(
 247       base::MessageLoopProxy::current().get(), sync_message_filter_.get());
 248
 249   resource_dispatcher_.reset(new ResourceDispatcher(this));
 250   socket_stream_dispatcher_.reset(new SocketStreamDispatcher());
 251   websocket_dispatcher_.reset(new WebSocketDispatcher);
 252   file_system_dispatcher_.reset(new FileSystemDispatcher());
 253
 254   histogram_message_filter_ = new ChildHistogramMessageFilter();
 255   resource_message_filter_ =
 256       new ChildResourceMessageFilter(resource_dispatcher());
 257
 258   service_worker_message_filter_ =
 259       new ServiceWorkerMessageFilter(thread_safe_sender_.get());
 260   service_worker_dispatcher_.reset(
 261       new ServiceWorkerDispatcher(thread_safe_sender_.get()));
 262
 263   quota_message_filter_ =
 264       new QuotaMessageFilter(thread_safe_sender_.get());
 265   quota_dispatcher_.reset(new QuotaDispatcher(thread_safe_sender_.get(),
 266                                               quota_message_filter_.get()));
 267
 268   channel_->AddFilter(histogram_message_filter_.get());
 269   channel_->AddFilter(sync_message_filter_.get());
 270   channel_->AddFilter(new tracing::ChildTraceMessageFilter(
 271       ChildProcess::current()->io_message_loop_proxy()));
 272   channel_->AddFilter(resource_message_filter_.get());
 273   channel_->AddFilter(quota_message_filter_->GetFilter());
 274   channel_->AddFilter(service_worker_message_filter_->GetFilter());
 275
 276   // In single process mode we may already have a power monitor
 277   if (!base::PowerMonitor::Get()) {
 278     scoped_ptr<PowerMonitorBroadcastSource> power_monitor_source(
 279       new PowerMonitorBroadcastSource());
 280     channel_->AddFilter(power_monitor_source->GetMessageFilter());
 281
 282     power_monitor_.reset(new base::PowerMonitor(
 283         power_monitor_source.PassAs<base::PowerMonitorSource>()));
 284   }
 285
 286 #if defined(OS_POSIX)
 287   // Check that --process-type is specified so we don't do this in unit tests
 288   // and single-process mode.
 289   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kProcessType))
 290     channel_->AddFilter(new SuicideOnChannelErrorFilter());
 291 #endif
 292
 293   base::MessageLoop::current()->PostDelayedTask(
 294       FROM_HERE,
 295       base::Bind(&ChildThread::EnsureConnected,
 296                  channel_connected_factory_.GetWeakPtr()),
 297       base::TimeDelta::FromSeconds(kConnectionTimeoutS));
 298
 299 #if defined(OS_ANDROID)
 300   {
 301     base::AutoLock lock(g_lazy_child_thread_lock.Get());
 302     g_child_thread = this;
 303   }
 304   // Signalling without locking is fine here because only
 305   // one thread can wait on the condition variable.
 306   g_lazy_child_thread_cv.Get().Signal();
 307 #endif
 308
 309 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED)
 310   trace_memory_controller_.reset(new base::debug::TraceMemoryController(
 311       message_loop_->message_loop_proxy(),
 312       ::HeapProfilerWithPseudoStackStart,
 313       ::HeapProfilerStop,
 314       ::GetHeapProfile));
 315 #endif
 316
 317   shared_bitmap_manager_.reset(
 318       new ChildSharedBitmapManager(thread_safe_sender()));
 319 }
 320
 321 ChildThread::~ChildThread() {
 322 #ifdef IPC_MESSAGE_LOG_ENABLED
 323   IPC::Logging::GetInstance()->SetIPCSender(NULL);
 324 #endif
 325
 326   channel_->RemoveFilter(histogram_message_filter_.get());
 327   channel_->RemoveFilter(sync_message_filter_.get());
 328
 329   // The ChannelProxy object caches a pointer to the IPC thread, so need to
 330   // reset it as it's not guaranteed to outlive this object.
 331   // NOTE: this also has the side-effect of not closing the main IPC channel to
 332   // the browser process.  This is needed because this is the signal that the
 333   // browser uses to know that this process has died, so we need it to be alive
 334   // until this process is shut down, and the OS closes the handle
 335   // automatically.  We used to watch the object handle on Windows to do this,
 336   // but it wasn't possible to do so on POSIX.
 337   channel_->ClearIPCTaskRunner();
 338   g_lazy_tls.Pointer()->Set(NULL);
 339 }
 340
 341 void ChildThread::Shutdown() {
 342   // Delete objects that hold references to blink so derived classes can
 343   // safely shutdown blink in their Shutdown implementation.
 344   file_system_dispatcher_.reset();
 345   quota_dispatcher_.reset();
 346 }
 347
 348 void ChildThread::OnChannelConnected(int32 peer_pid) {
 349   channel_connected_factory_.InvalidateWeakPtrs();
 350 }
 351
 352 void ChildThread::OnChannelError() {
 353   set_on_channel_error_called(true);
 354   base::MessageLoop::current()->Quit();
 355 }
 356
 357 bool ChildThread::Send(IPC::Message* msg) {
 358   DCHECK(base::MessageLoop::current() == message_loop());
 359   if (!channel_) {
 360     delete msg;
 361     return false;
 362   }
 363
 364   return channel_->Send(msg);
 365 }
 366
 367 MessageRouter* ChildThread::GetRouter() {
 368   DCHECK(base::MessageLoop::current() == message_loop());
 369   return &router_;
 370 }
 371
 372 webkit_glue::ResourceLoaderBridge* ChildThread::CreateBridge(
 373     const RequestInfo& request_info) {
 374   return resource_dispatcher()->CreateBridge(request_info);
 375 }
 376
 377 base::SharedMemory* ChildThread::AllocateSharedMemory(size_t buf_size) {
 378   return AllocateSharedMemory(buf_size, this);
 379 }
 380
 381 // static
 382 base::SharedMemory* ChildThread::AllocateSharedMemory(
 383     size_t buf_size,
 384     IPC::Sender* sender) {
 385   scoped_ptr<base::SharedMemory> shared_buf;
 386 #if defined(OS_WIN)
 387   shared_buf.reset(new base::SharedMemory);
 388   if (!shared_buf->CreateAndMapAnonymous(buf_size)) {
 389     NOTREACHED();
 390     return NULL;
 391   }
 392 #else
 393   // On POSIX, we need to ask the browser to create the shared memory for us,
 394   // since this is blocked by the sandbox.
 395   base::SharedMemoryHandle shared_mem_handle;
 396   if (sender->Send(new ChildProcessHostMsg_SyncAllocateSharedMemory(
 397                            buf_size, &shared_mem_handle))) {
 398     if (base::SharedMemory::IsHandleValid(shared_mem_handle)) {
 399       shared_buf.reset(new base::SharedMemory(shared_mem_handle, false));
 400       if (!shared_buf->Map(buf_size)) {
 401         NOTREACHED() << "Map failed";
 402         return NULL;
 403       }
 404     } else {
 405       NOTREACHED() << "Browser failed to allocate shared memory";
 406       return NULL;
 407     }
 408   } else {
 409     NOTREACHED() << "Browser allocation request message failed";
 410     return NULL;
 411   }
 412 #endif
 413   return shared_buf.release();
 414 }
 415
 416 bool ChildThread::OnMessageReceived(const IPC::Message& msg) {
 417   // Resource responses are sent to the resource dispatcher.
 418   if (resource_dispatcher_->OnMessageReceived(msg))
 419     return true;
 420   if (socket_stream_dispatcher_->OnMessageReceived(msg))
 421     return true;
 422   if (websocket_dispatcher_->OnMessageReceived(msg))
 423     return true;
 424   if (file_system_dispatcher_->OnMessageReceived(msg))
 425     return true;
 426
 427   bool handled = true;
 428   IPC_BEGIN_MESSAGE_MAP(ChildThread, msg)
 429     IPC_MESSAGE_HANDLER(ChildProcessMsg_Shutdown, OnShutdown)
 430 #if defined(IPC_MESSAGE_LOG_ENABLED)
 431     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetIPCLoggingEnabled,
 432                         OnSetIPCLoggingEnabled)
 433 #endif
 434     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetProfilerStatus,
 435                         OnSetProfilerStatus)
 436     IPC_MESSAGE_HANDLER(ChildProcessMsg_GetChildProfilerData,
 437                         OnGetChildProfilerData)
 438     IPC_MESSAGE_HANDLER(ChildProcessMsg_DumpHandles, OnDumpHandles)
 439 #if defined(USE_TCMALLOC)
 440     IPC_MESSAGE_HANDLER(ChildProcessMsg_GetTcmallocStats, OnGetTcmallocStats)
 441 #endif
 442     IPC_MESSAGE_UNHANDLED(handled = false)
 443   IPC_END_MESSAGE_MAP()
 444
 445   if (handled)
 446     return true;
 447
 448   if (msg.routing_id() == MSG_ROUTING_CONTROL)
 449     return OnControlMessageReceived(msg);
 450
 451   return router_.OnMessageReceived(msg);
 452 }
 453
 454 bool ChildThread::OnControlMessageReceived(const IPC::Message& msg) {
 455   return false;
 456 }
 457
 458 void ChildThread::OnShutdown() {
 459   base::MessageLoop::current()->Quit();
 460 }
 461
 462 #if defined(IPC_MESSAGE_LOG_ENABLED)
 463 void ChildThread::OnSetIPCLoggingEnabled(bool enable) {
 464   if (enable)
 465     IPC::Logging::GetInstance()->Enable();
 466   else
 467     IPC::Logging::GetInstance()->Disable();
 468 }
 469 #endif  //  IPC_MESSAGE_LOG_ENABLED
 470
 471 void ChildThread::OnSetProfilerStatus(ThreadData::Status status) {
 472   ThreadData::InitializeAndSetTrackingStatus(status);
 473 }
 474
 475 void ChildThread::OnGetChildProfilerData(int sequence_number) {
 476   tracked_objects::ProcessDataSnapshot process_data;
 477   ThreadData::Snapshot(false, &process_data);
 478
 479   Send(new ChildProcessHostMsg_ChildProfilerData(sequence_number,
 480                                                  process_data));
 481 }
 482
 483 void ChildThread::OnDumpHandles() {
 484 #if defined(OS_WIN)
 485   scoped_refptr<HandleEnumerator> handle_enum(
 486       new HandleEnumerator(
 487           CommandLine::ForCurrentProcess()->HasSwitch(
 488               switches::kAuditAllHandles)));
 489   handle_enum->EnumerateHandles();
 490   Send(new ChildProcessHostMsg_DumpHandlesDone);
 491 #else
 492   NOTIMPLEMENTED();
 493 #endif
 494 }
 495
 496 #if defined(USE_TCMALLOC)
 497 void ChildThread::OnGetTcmallocStats() {
 498   std::string result;
 499   char buffer[1024 * 32];
 500   base::allocator::GetStats(buffer, sizeof(buffer));
 501   result.append(buffer);
 502   Send(new ChildProcessHostMsg_TcmallocStats(result));
 503 }
 504 #endif
 505
 506 ChildThread* ChildThread::current() {
 507   return g_lazy_tls.Pointer()->Get();
 508 }
 509
 510 #if defined(OS_ANDROID)
 511 // The method must NOT be called on the child thread itself.
 512 // It may block the child thread if so.
 513 void ChildThread::ShutdownThread() {
 514   DCHECK(!ChildThread::current()) <<
 515       "this method should NOT be called from child thread itself";
 516   {
 517     base::AutoLock lock(g_lazy_child_thread_lock.Get());
 518     while (!g_child_thread)
 519       g_lazy_child_thread_cv.Get().Wait();
 520   }
 521   DCHECK_NE(base::MessageLoop::current(), g_child_thread->message_loop());
 522   g_child_thread->message_loop()->PostTask(
 523       FROM_HERE, base::Bind(&QuitMainThreadMessageLoop));
 524 }
 525 #endif
 526
 527 void ChildThread::OnProcessFinalRelease() {
 528   if (on_channel_error_called_) {
 529     base::MessageLoop::current()->Quit();
 530     return;
 531   }
 532
 533   // The child process shutdown sequence is a request response based mechanism,
 534   // where we send out an initial feeler request to the child process host
 535   // instance in the browser to verify if it's ok to shutdown the child process.
 536   // The browser then sends back a response if it's ok to shutdown. This avoids
 537   // race conditions if the process refcount is 0 but there's an IPC message
 538   // inflight that would addref it.
 539   Send(new ChildProcessHostMsg_ShutdownRequest);
 540 }
 541
 542 void ChildThread::EnsureConnected() {
 543   VLOG(0) << "ChildThread::EnsureConnected()";
 544   base::KillProcess(base::GetCurrentProcessHandle(), 0, false);
 545 }
 546
 547 }  // namespace content