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