src/content/common/gpu/gpu_channel.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 #if defined(OS_WIN)
   6 #include <windows.h>
   7 #endif
   8
   9 #include "content/common/gpu/gpu_channel.h"
  10
  11 #include <queue>
  12 #include <vector>
  13
  14 #include "base/bind.h"
  15 #include "base/command_line.h"
  16 #include "base/debug/trace_event.h"
  17 #include "base/message_loop/message_loop_proxy.h"
  18 #include "base/strings/string_util.h"
  19 #include "base/timer/timer.h"
  20 #include "content/common/gpu/devtools_gpu_agent.h"
  21 #include "content/common/gpu/gpu_channel_manager.h"
  22 #include "content/common/gpu/gpu_messages.h"
  23 #include "content/common/gpu/media/gpu_video_encode_accelerator.h"
  24 #include "content/common/gpu/sync_point_manager.h"
  25 #include "content/public/common/content_switches.h"
  26 #include "gpu/command_buffer/common/mailbox.h"
  27 #include "gpu/command_buffer/service/gpu_scheduler.h"
  28 #include "gpu/command_buffer/service/image_manager.h"
  29 #include "gpu/command_buffer/service/mailbox_manager.h"
  30 #include "ipc/ipc_channel.h"
  31 #include "ipc/ipc_channel_proxy.h"
  32 #include "ui/gl/gl_context.h"
  33 #include "ui/gl/gl_image.h"
  34 #include "ui/gl/gl_surface.h"
  35
  36 #if defined(OS_POSIX)
  37 #include "ipc/ipc_channel_posix.h"
  38 #endif
  39
  40 namespace content {
  41 namespace {
  42
  43 // Number of milliseconds between successive vsync. Many GL commands block
  44 // on vsync, so thresholds for preemption should be multiples of this.
  45 const int64 kVsyncIntervalMs = 17;
  46
  47 // Amount of time that we will wait for an IPC to be processed before
  48 // preempting. After a preemption, we must wait this long before triggering
  49 // another preemption.
  50 const int64 kPreemptWaitTimeMs = 2 * kVsyncIntervalMs;
  51
  52 // Once we trigger a preemption, the maximum duration that we will wait
  53 // before clearing the preemption.
  54 const int64 kMaxPreemptTimeMs = kVsyncIntervalMs;
  55
  56 // Stop the preemption once the time for the longest pending IPC drops
  57 // below this threshold.
  58 const int64 kStopPreemptThresholdMs = kVsyncIntervalMs;
  59
  60 }  // anonymous namespace
  61
  62 // This filter does three things:
  63 // - it counts and timestamps each message forwarded to the channel
  64 //   so that we can preempt other channels if a message takes too long to
  65 //   process. To guarantee fairness, we must wait a minimum amount of time
  66 //   before preempting and we limit the amount of time that we can preempt in
  67 //   one shot (see constants above).
  68 // - it handles the GpuCommandBufferMsg_InsertSyncPoint message on the IO
  69 //   thread, generating the sync point ID and responding immediately, and then
  70 //   posting a task to insert the GpuCommandBufferMsg_RetireSyncPoint message
  71 //   into the channel's queue.
  72 // - it generates mailbox names for clients of the GPU process on the IO thread.
  73 class GpuChannelMessageFilter : public IPC::ChannelProxy::MessageFilter {
  74  public:
  75   // Takes ownership of gpu_channel (see below).
  76   GpuChannelMessageFilter(base::WeakPtr<GpuChannel>* gpu_channel,
  77                           scoped_refptr<SyncPointManager> sync_point_manager,
  78                           scoped_refptr<base::MessageLoopProxy> message_loop)
  79       : preemption_state_(IDLE),
  80         gpu_channel_(gpu_channel),
  81         channel_(NULL),
  82         sync_point_manager_(sync_point_manager),
  83         message_loop_(message_loop),
  84         messages_forwarded_to_channel_(0),
  85         a_stub_is_descheduled_(false) {
  86   }
  87
  88   virtual void OnFilterAdded(IPC::Channel* channel) OVERRIDE {
  89     DCHECK(!channel_);
  90     channel_ = channel;
  91   }
  92
  93   virtual void OnFilterRemoved() OVERRIDE {
  94     DCHECK(channel_);
  95     channel_ = NULL;
  96   }
  97
  98   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE {
  99     DCHECK(channel_);
 100
 101     bool handled = false;
 102     if (message.type() == GpuCommandBufferMsg_RetireSyncPoint::ID) {
 103       // This message should not be sent explicitly by the renderer.
 104       DLOG(ERROR) << "Client should not send "
 105                      "GpuCommandBufferMsg_RetireSyncPoint message";
 106       handled = true;
 107     }
 108
 109     // All other messages get processed by the GpuChannel.
 110     if (!handled) {
 111       messages_forwarded_to_channel_++;
 112       if (preempting_flag_.get())
 113         pending_messages_.push(PendingMessage(messages_forwarded_to_channel_));
 114       UpdatePreemptionState();
 115     }
 116
 117     if (message.type() == GpuCommandBufferMsg_InsertSyncPoint::ID) {
 118       uint32 sync_point = sync_point_manager_->GenerateSyncPoint();
 119       IPC::Message* reply = IPC::SyncMessage::GenerateReply(&message);
 120       GpuCommandBufferMsg_InsertSyncPoint::WriteReplyParams(reply, sync_point);
 121       Send(reply);
 122       message_loop_->PostTask(FROM_HERE, base::Bind(
 123           &GpuChannelMessageFilter::InsertSyncPointOnMainThread,
 124           gpu_channel_,
 125           sync_point_manager_,
 126           message.routing_id(),
 127           sync_point));
 128       handled = true;
 129     }
 130     return handled;
 131   }
 132
 133   void MessageProcessed(uint64 messages_processed) {
 134     while (!pending_messages_.empty() &&
 135            pending_messages_.front().message_number <= messages_processed)
 136       pending_messages_.pop();
 137     UpdatePreemptionState();
 138   }
 139
 140   void SetPreemptingFlagAndSchedulingState(
 141       gpu::PreemptionFlag* preempting_flag,
 142       bool a_stub_is_descheduled) {
 143     preempting_flag_ = preempting_flag;
 144     a_stub_is_descheduled_ = a_stub_is_descheduled;
 145   }
 146
 147   void UpdateStubSchedulingState(bool a_stub_is_descheduled) {
 148     a_stub_is_descheduled_ = a_stub_is_descheduled;
 149     UpdatePreemptionState();
 150   }
 151
 152   bool Send(IPC::Message* message) {
 153     return channel_->Send(message);
 154   }
 155
 156  protected:
 157   virtual ~GpuChannelMessageFilter() {
 158     message_loop_->PostTask(FROM_HERE, base::Bind(
 159         &GpuChannelMessageFilter::DeleteWeakPtrOnMainThread, gpu_channel_));
 160   }
 161
 162  private:
 163   enum PreemptionState {
 164     // Either there's no other channel to preempt, there are no messages
 165     // pending processing, or we just finished preempting and have to wait
 166     // before preempting again.
 167     IDLE,
 168     // We are waiting kPreemptWaitTimeMs before checking if we should preempt.
 169     WAITING,
 170     // We can preempt whenever any IPC processing takes more than
 171     // kPreemptWaitTimeMs.
 172     CHECKING,
 173     // We are currently preempting (i.e. no stub is descheduled).
 174     PREEMPTING,
 175     // We would like to preempt, but some stub is descheduled.
 176     WOULD_PREEMPT_DESCHEDULED,
 177   };
 178
 179   PreemptionState preemption_state_;
 180
 181   // Maximum amount of time that we can spend in PREEMPTING.
 182   // It is reset when we transition to IDLE.
 183   base::TimeDelta max_preemption_time_;
 184
 185   struct PendingMessage {
 186     uint64 message_number;
 187     base::TimeTicks time_received;
 188
 189     explicit PendingMessage(uint64 message_number)
 190         : message_number(message_number),
 191           time_received(base::TimeTicks::Now()) {
 192     }
 193   };
 194
 195   void UpdatePreemptionState() {
 196     switch (preemption_state_) {
 197       case IDLE:
 198         if (preempting_flag_.get() && !pending_messages_.empty())
 199           TransitionToWaiting();
 200         break;
 201       case WAITING:
 202         // A timer will transition us to CHECKING.
 203         DCHECK(timer_.IsRunning());
 204         break;
 205       case CHECKING:
 206         if (!pending_messages_.empty()) {
 207           base::TimeDelta time_elapsed =
 208               base::TimeTicks::Now() - pending_messages_.front().time_received;
 209           if (time_elapsed.InMilliseconds() < kPreemptWaitTimeMs) {
 210             // Schedule another check for when the IPC may go long.
 211             timer_.Start(
 212                 FROM_HERE,
 213                 base::TimeDelta::FromMilliseconds(kPreemptWaitTimeMs) -
 214                     time_elapsed,
 215                 this, &GpuChannelMessageFilter::UpdatePreemptionState);
 216           } else {
 217             if (a_stub_is_descheduled_)
 218               TransitionToWouldPreemptDescheduled();
 219             else
 220               TransitionToPreempting();
 221           }
 222         }
 223         break;
 224       case PREEMPTING:
 225         // A TransitionToIdle() timer should always be running in this state.
 226         DCHECK(timer_.IsRunning());
 227         if (a_stub_is_descheduled_)
 228           TransitionToWouldPreemptDescheduled();
 229         else
 230           TransitionToIdleIfCaughtUp();
 231         break;
 232       case WOULD_PREEMPT_DESCHEDULED:
 233         // A TransitionToIdle() timer should never be running in this state.
 234         DCHECK(!timer_.IsRunning());
 235         if (!a_stub_is_descheduled_)
 236           TransitionToPreempting();
 237         else
 238           TransitionToIdleIfCaughtUp();
 239         break;
 240       default:
 241         NOTREACHED();
 242     }
 243   }
 244
 245   void TransitionToIdleIfCaughtUp() {
 246     DCHECK(preemption_state_ == PREEMPTING ||
 247            preemption_state_ == WOULD_PREEMPT_DESCHEDULED);
 248     if (pending_messages_.empty()) {
 249       TransitionToIdle();
 250     } else {
 251       base::TimeDelta time_elapsed =
 252           base::TimeTicks::Now() - pending_messages_.front().time_received;
 253       if (time_elapsed.InMilliseconds() < kStopPreemptThresholdMs)
 254         TransitionToIdle();
 255     }
 256   }
 257
 258   void TransitionToIdle() {
 259     DCHECK(preemption_state_ == PREEMPTING ||
 260            preemption_state_ == WOULD_PREEMPT_DESCHEDULED);
 261     // Stop any outstanding timer set to force us from PREEMPTING to IDLE.
 262     timer_.Stop();
 263
 264     preemption_state_ = IDLE;
 265     preempting_flag_->Reset();
 266     TRACE_COUNTER_ID1("gpu", "GpuChannel::Preempting", this, 0);
 267
 268     UpdatePreemptionState();
 269   }
 270
 271   void TransitionToWaiting() {
 272     DCHECK_EQ(preemption_state_, IDLE);
 273     DCHECK(!timer_.IsRunning());
 274
 275     preemption_state_ = WAITING;
 276     timer_.Start(
 277         FROM_HERE,
 278         base::TimeDelta::FromMilliseconds(kPreemptWaitTimeMs),
 279         this, &GpuChannelMessageFilter::TransitionToChecking);
 280   }
 281
 282   void TransitionToChecking() {
 283     DCHECK_EQ(preemption_state_, WAITING);
 284     DCHECK(!timer_.IsRunning());
 285
 286     preemption_state_ = CHECKING;
 287     max_preemption_time_ = base::TimeDelta::FromMilliseconds(kMaxPreemptTimeMs);
 288     UpdatePreemptionState();
 289   }
 290
 291   void TransitionToPreempting() {
 292     DCHECK(preemption_state_ == CHECKING ||
 293            preemption_state_ == WOULD_PREEMPT_DESCHEDULED);
 294     DCHECK(!a_stub_is_descheduled_);
 295
 296     // Stop any pending state update checks that we may have queued
 297     // while CHECKING.
 298     if (preemption_state_ == CHECKING)
 299       timer_.Stop();
 300
 301     preemption_state_ = PREEMPTING;
 302     preempting_flag_->Set();
 303     TRACE_COUNTER_ID1("gpu", "GpuChannel::Preempting", this, 1);
 304
 305     timer_.Start(
 306        FROM_HERE,
 307        max_preemption_time_,
 308        this, &GpuChannelMessageFilter::TransitionToIdle);
 309
 310     UpdatePreemptionState();
 311   }
 312
 313   void TransitionToWouldPreemptDescheduled() {
 314     DCHECK(preemption_state_ == CHECKING ||
 315            preemption_state_ == PREEMPTING);
 316     DCHECK(a_stub_is_descheduled_);
 317
 318     if (preemption_state_ == CHECKING) {
 319       // Stop any pending state update checks that we may have queued
 320       // while CHECKING.
 321       timer_.Stop();
 322     } else {
 323       // Stop any TransitionToIdle() timers that we may have queued
 324       // while PREEMPTING.
 325       timer_.Stop();
 326       max_preemption_time_ = timer_.desired_run_time() - base::TimeTicks::Now();
 327       if (max_preemption_time_ < base::TimeDelta()) {
 328         TransitionToIdle();
 329         return;
 330       }
 331     }
 332
 333     preemption_state_ = WOULD_PREEMPT_DESCHEDULED;
 334     preempting_flag_->Reset();
 335     TRACE_COUNTER_ID1("gpu", "GpuChannel::Preempting", this, 0);
 336
 337     UpdatePreemptionState();
 338   }
 339
 340   static void InsertSyncPointOnMainThread(
 341       base::WeakPtr<GpuChannel>* gpu_channel,
 342       scoped_refptr<SyncPointManager> manager,
 343       int32 routing_id,
 344       uint32 sync_point) {
 345     // This function must ensure that the sync point will be retired. Normally
 346     // we'll find the stub based on the routing ID, and associate the sync point
 347     // with it, but if that fails for any reason (channel or stub already
 348     // deleted, invalid routing id), we need to retire the sync point
 349     // immediately.
 350     if (gpu_channel->get()) {
 351       GpuCommandBufferStub* stub = gpu_channel->get()->LookupCommandBuffer(
 352           routing_id);
 353       if (stub) {
 354         stub->AddSyncPoint(sync_point);
 355         GpuCommandBufferMsg_RetireSyncPoint message(routing_id, sync_point);
 356         gpu_channel->get()->OnMessageReceived(message);
 357         return;
 358       } else {
 359         gpu_channel->get()->MessageProcessed();
 360       }
 361     }
 362     manager->RetireSyncPoint(sync_point);
 363   }
 364
 365   static void DeleteWeakPtrOnMainThread(
 366       base::WeakPtr<GpuChannel>* gpu_channel) {
 367     delete gpu_channel;
 368   }
 369
 370   // NOTE: this is a pointer to a weak pointer. It is never dereferenced on the
 371   // IO thread, it's only passed through - therefore the WeakPtr assumptions are
 372   // respected.
 373   base::WeakPtr<GpuChannel>* gpu_channel_;
 374   IPC::Channel* channel_;
 375   scoped_refptr<SyncPointManager> sync_point_manager_;
 376   scoped_refptr<base::MessageLoopProxy> message_loop_;
 377   scoped_refptr<gpu::PreemptionFlag> preempting_flag_;
 378
 379   std::queue<PendingMessage> pending_messages_;
 380
 381   // Count of the number of IPCs forwarded to the GpuChannel.
 382   uint64 messages_forwarded_to_channel_;
 383
 384   base::OneShotTimer<GpuChannelMessageFilter> timer_;
 385
 386   bool a_stub_is_descheduled_;
 387 };
 388
 389 GpuChannel::GpuChannel(GpuChannelManager* gpu_channel_manager,
 390                        GpuWatchdog* watchdog,
 391                        gfx::GLShareGroup* share_group,
 392                        gpu::gles2::MailboxManager* mailbox,
 393                        int client_id,
 394                        bool software)
 395     : gpu_channel_manager_(gpu_channel_manager),
 396       messages_processed_(0),
 397       client_id_(client_id),
 398       share_group_(share_group ? share_group : new gfx::GLShareGroup),
 399       mailbox_manager_(mailbox ? mailbox : new gpu::gles2::MailboxManager),
 400       image_manager_(new gpu::gles2::ImageManager),
 401       watchdog_(watchdog),
 402       software_(software),
 403       handle_messages_scheduled_(false),
 404       processed_get_state_fast_(false),
 405       currently_processing_message_(NULL),
 406       weak_factory_(this),
 407       num_stubs_descheduled_(0) {
 408   DCHECK(gpu_channel_manager);
 409   DCHECK(client_id);
 410
 411   channel_id_ = IPC::Channel::GenerateVerifiedChannelID("gpu");
 412   const CommandLine* command_line = CommandLine::ForCurrentProcess();
 413   log_messages_ = command_line->HasSwitch(switches::kLogPluginMessages);
 414 }
 415
 416
 417 bool GpuChannel::Init(base::MessageLoopProxy* io_message_loop,
 418                       base::WaitableEvent* shutdown_event) {
 419   DCHECK(!channel_.get());
 420
 421   // Map renderer ID to a (single) channel to that process.
 422   channel_.reset(new IPC::SyncChannel(
 423       channel_id_,
 424       IPC::Channel::MODE_SERVER,
 425       this,
 426       io_message_loop,
 427       false,
 428       shutdown_event));
 429
 430   base::WeakPtr<GpuChannel>* weak_ptr(new base::WeakPtr<GpuChannel>(
 431       weak_factory_.GetWeakPtr()));
 432
 433   filter_ = new GpuChannelMessageFilter(
 434       weak_ptr,
 435       gpu_channel_manager_->sync_point_manager(),
 436       base::MessageLoopProxy::current());
 437   io_message_loop_ = io_message_loop;
 438   channel_->AddFilter(filter_.get());
 439
 440   devtools_gpu_agent_.reset(new DevToolsGpuAgent(this));
 441
 442   return true;
 443 }
 444
 445 std::string GpuChannel::GetChannelName() {
 446   return channel_id_;
 447 }
 448
 449 #if defined(OS_POSIX)
 450 int GpuChannel::TakeRendererFileDescriptor() {
 451   if (!channel_) {
 452     NOTREACHED();
 453     return -1;
 454   }
 455   return channel_->TakeClientFileDescriptor();
 456 }
 457 #endif  // defined(OS_POSIX)
 458
 459 bool GpuChannel::OnMessageReceived(const IPC::Message& message) {
 460   if (log_messages_) {
 461     DVLOG(1) << "received message @" << &message << " on channel @" << this
 462              << " with type " << message.type();
 463   }
 464
 465   if (message.type() == GpuCommandBufferMsg_GetStateFast::ID) {
 466     if (processed_get_state_fast_) {
 467       // Require a non-GetStateFast message in between two GetStateFast
 468       // messages, to ensure progress is made.
 469       std::deque<IPC::Message*>::iterator point = deferred_messages_.begin();
 470
 471       while (point != deferred_messages_.end() &&
 472              (*point)->type() == GpuCommandBufferMsg_GetStateFast::ID) {
 473         ++point;
 474       }
 475
 476       if (point != deferred_messages_.end()) {
 477         ++point;
 478       }
 479
 480       deferred_messages_.insert(point, new IPC::Message(message));
 481     } else {
 482       // Move GetStateFast commands to the head of the queue, so the renderer
 483       // doesn't have to wait any longer than necessary.
 484       deferred_messages_.push_front(new IPC::Message(message));
 485     }
 486   } else {
 487     deferred_messages_.push_back(new IPC::Message(message));
 488   }
 489
 490   OnScheduled();
 491
 492   return true;
 493 }
 494
 495 void GpuChannel::OnChannelError() {
 496   gpu_channel_manager_->RemoveChannel(client_id_);
 497 }
 498
 499 bool GpuChannel::Send(IPC::Message* message) {
 500   // The GPU process must never send a synchronous IPC message to the renderer
 501   // process. This could result in deadlock.
 502   DCHECK(!message->is_sync());
 503   if (log_messages_) {
 504     DVLOG(1) << "sending message @" << message << " on channel @" << this
 505              << " with type " << message->type();
 506   }
 507
 508   if (!channel_) {
 509     delete message;
 510     return false;
 511   }
 512
 513   return channel_->Send(message);
 514 }
 515
 516 void GpuChannel::RequeueMessage() {
 517   DCHECK(currently_processing_message_);
 518   deferred_messages_.push_front(
 519       new IPC::Message(*currently_processing_message_));
 520   messages_processed_--;
 521   currently_processing_message_ = NULL;
 522 }
 523
 524 void GpuChannel::OnScheduled() {
 525   if (handle_messages_scheduled_)
 526     return;
 527   // Post a task to handle any deferred messages. The deferred message queue is
 528   // not emptied here, which ensures that OnMessageReceived will continue to
 529   // defer newly received messages until the ones in the queue have all been
 530   // handled by HandleMessage. HandleMessage is invoked as a
 531   // task to prevent reentrancy.
 532   base::MessageLoop::current()->PostTask(
 533       FROM_HERE,
 534       base::Bind(&GpuChannel::HandleMessage, weak_factory_.GetWeakPtr()));
 535   handle_messages_scheduled_ = true;
 536 }
 537
 538 void GpuChannel::StubSchedulingChanged(bool scheduled) {
 539   bool a_stub_was_descheduled = num_stubs_descheduled_ > 0;
 540   if (scheduled) {
 541     num_stubs_descheduled_--;
 542     OnScheduled();
 543   } else {
 544     num_stubs_descheduled_++;
 545   }
 546   DCHECK_LE(num_stubs_descheduled_, stubs_.size());
 547   bool a_stub_is_descheduled = num_stubs_descheduled_ > 0;
 548
 549   if (a_stub_is_descheduled != a_stub_was_descheduled) {
 550     if (preempting_flag_.get()) {
 551       io_message_loop_->PostTask(
 552           FROM_HERE,
 553           base::Bind(&GpuChannelMessageFilter::UpdateStubSchedulingState,
 554                      filter_,
 555                      a_stub_is_descheduled));
 556     }
 557   }
 558 }
 559
 560 void GpuChannel::CreateViewCommandBuffer(
 561     const gfx::GLSurfaceHandle& window,
 562     int32 surface_id,
 563     const GPUCreateCommandBufferConfig& init_params,
 564     int32* route_id) {
 565   TRACE_EVENT1("gpu",
 566                "GpuChannel::CreateViewCommandBuffer",
 567                "surface_id",
 568                surface_id);
 569
 570   *route_id = MSG_ROUTING_NONE;
 571
 572   GpuCommandBufferStub* share_group = stubs_.Lookup(init_params.share_group_id);
 573
 574   // Virtualize compositor contexts on OS X to prevent performance regressions
 575   // when enabling FCM.
 576   // http://crbug.com/180463
 577   bool use_virtualized_gl_context = false;
 578 #if defined(OS_MACOSX)
 579   use_virtualized_gl_context = true;
 580 #endif
 581
 582   *route_id = GenerateRouteID();
 583   scoped_ptr<GpuCommandBufferStub> stub(
 584       new GpuCommandBufferStub(this,
 585                                share_group,
 586                                window,
 587                                mailbox_manager_.get(),
 588                                image_manager_.get(),
 589                                gfx::Size(),
 590                                disallowed_features_,
 591                                init_params.attribs,
 592                                init_params.gpu_preference,
 593                                use_virtualized_gl_context,
 594                                *route_id,
 595                                surface_id,
 596                                watchdog_,
 597                                software_,
 598                                init_params.active_url));
 599   if (preempted_flag_.get())
 600     stub->SetPreemptByFlag(preempted_flag_);
 601   router_.AddRoute(*route_id, stub.get());
 602   stubs_.AddWithID(stub.release(), *route_id);
 603 }
 604
 605 GpuCommandBufferStub* GpuChannel::LookupCommandBuffer(int32 route_id) {
 606   return stubs_.Lookup(route_id);
 607 }
 608
 609 void GpuChannel::CreateImage(
 610     gfx::PluginWindowHandle window,
 611     int32 image_id,
 612     gfx::Size* size) {
 613   TRACE_EVENT1("gpu",
 614                "GpuChannel::CreateImage",
 615                "image_id",
 616                image_id);
 617
 618   *size = gfx::Size();
 619
 620   if (image_manager_->LookupImage(image_id)) {
 621     LOG(ERROR) << "CreateImage failed, image_id already in use.";
 622     return;
 623   }
 624
 625   scoped_refptr<gfx::GLImage> image = gfx::GLImage::CreateGLImage(window);
 626   if (!image.get())
 627     return;
 628
 629   image_manager_->AddImage(image.get(), image_id);
 630   *size = image->GetSize();
 631 }
 632
 633 void GpuChannel::DeleteImage(int32 image_id) {
 634   TRACE_EVENT1("gpu",
 635                "GpuChannel::DeleteImage",
 636                "image_id",
 637                image_id);
 638
 639   image_manager_->RemoveImage(image_id);
 640 }
 641
 642 void GpuChannel::LoseAllContexts() {
 643   gpu_channel_manager_->LoseAllContexts();
 644 }
 645
 646 void GpuChannel::MarkAllContextsLost() {
 647   for (StubMap::Iterator<GpuCommandBufferStub> it(&stubs_);
 648        !it.IsAtEnd(); it.Advance()) {
 649     it.GetCurrentValue()->MarkContextLost();
 650   }
 651 }
 652
 653 void GpuChannel::DestroySoon() {
 654   base::MessageLoop::current()->PostTask(
 655       FROM_HERE, base::Bind(&GpuChannel::OnDestroy, this));
 656 }
 657
 658 int32 GpuChannel::GenerateRouteID() {
 659   static int32 last_id = 0;
 660   return ++last_id;
 661 }
 662
 663 void GpuChannel::AddRoute(int32 route_id, IPC::Listener* listener) {
 664   router_.AddRoute(route_id, listener);
 665 }
 666
 667 void GpuChannel::RemoveRoute(int32 route_id) {
 668   router_.RemoveRoute(route_id);
 669 }
 670
 671 gpu::PreemptionFlag* GpuChannel::GetPreemptionFlag() {
 672   if (!preempting_flag_.get()) {
 673     preempting_flag_ = new gpu::PreemptionFlag;
 674     io_message_loop_->PostTask(
 675         FROM_HERE, base::Bind(
 676             &GpuChannelMessageFilter::SetPreemptingFlagAndSchedulingState,
 677             filter_, preempting_flag_, num_stubs_descheduled_ > 0));
 678   }
 679   return preempting_flag_.get();
 680 }
 681
 682 void GpuChannel::SetPreemptByFlag(
 683     scoped_refptr<gpu::PreemptionFlag> preempted_flag) {
 684   preempted_flag_ = preempted_flag;
 685
 686   for (StubMap::Iterator<GpuCommandBufferStub> it(&stubs_);
 687        !it.IsAtEnd(); it.Advance()) {
 688     it.GetCurrentValue()->SetPreemptByFlag(preempted_flag_);
 689   }
 690 }
 691
 692 GpuChannel::~GpuChannel() {
 693   if (preempting_flag_.get())
 694     preempting_flag_->Reset();
 695 }
 696
 697 void GpuChannel::OnDestroy() {
 698   TRACE_EVENT0("gpu", "GpuChannel::OnDestroy");
 699   gpu_channel_manager_->RemoveChannel(client_id_);
 700 }
 701
 702 bool GpuChannel::OnControlMessageReceived(const IPC::Message& msg) {
 703   bool handled = true;
 704   IPC_BEGIN_MESSAGE_MAP(GpuChannel, msg)
 705     IPC_MESSAGE_HANDLER(GpuChannelMsg_CreateOffscreenCommandBuffer,
 706                         OnCreateOffscreenCommandBuffer)
 707     IPC_MESSAGE_HANDLER(GpuChannelMsg_DestroyCommandBuffer,
 708                         OnDestroyCommandBuffer)
 709     IPC_MESSAGE_HANDLER(GpuChannelMsg_CreateVideoEncoder, OnCreateVideoEncoder)
 710     IPC_MESSAGE_HANDLER(GpuChannelMsg_DestroyVideoEncoder,
 711                         OnDestroyVideoEncoder)
 712     IPC_MESSAGE_HANDLER(GpuChannelMsg_DevToolsStartEventsRecording,
 713                         OnDevToolsStartEventsRecording)
 714     IPC_MESSAGE_HANDLER(GpuChannelMsg_DevToolsStopEventsRecording,
 715                         OnDevToolsStopEventsRecording)
 716     IPC_MESSAGE_UNHANDLED(handled = false)
 717   IPC_END_MESSAGE_MAP()
 718   DCHECK(handled) << msg.type();
 719   return handled;
 720 }
 721
 722 void GpuChannel::HandleMessage() {
 723   handle_messages_scheduled_ = false;
 724   if (deferred_messages_.empty())
 725     return;
 726
 727   bool should_fast_track_ack = false;
 728   IPC::Message* m = deferred_messages_.front();
 729   GpuCommandBufferStub* stub = stubs_.Lookup(m->routing_id());
 730
 731   do {
 732     if (stub) {
 733       if (!stub->IsScheduled())
 734         return;
 735       if (stub->IsPreempted()) {
 736         OnScheduled();
 737         return;
 738       }
 739     }
 740
 741     scoped_ptr<IPC::Message> message(m);
 742     deferred_messages_.pop_front();
 743     bool message_processed = true;
 744
 745     processed_get_state_fast_ =
 746         (message->type() == GpuCommandBufferMsg_GetStateFast::ID);
 747
 748     currently_processing_message_ = message.get();
 749     bool result;
 750     if (message->routing_id() == MSG_ROUTING_CONTROL)
 751       result = OnControlMessageReceived(*message);
 752     else
 753       result = router_.RouteMessage(*message);
 754     currently_processing_message_ = NULL;
 755
 756     if (!result) {
 757       // Respond to sync messages even if router failed to route.
 758       if (message->is_sync()) {
 759         IPC::Message* reply = IPC::SyncMessage::GenerateReply(&*message);
 760         reply->set_reply_error();
 761         Send(reply);
 762       }
 763     } else {
 764       // If the command buffer becomes unscheduled as a result of handling the
 765       // message but still has more commands to process, synthesize an IPC
 766       // message to flush that command buffer.
 767       if (stub) {
 768         if (stub->HasUnprocessedCommands()) {
 769           deferred_messages_.push_front(new GpuCommandBufferMsg_Rescheduled(
 770               stub->route_id()));
 771           message_processed = false;
 772         }
 773       }
 774     }
 775     if (message_processed)
 776       MessageProcessed();
 777
 778     // We want the EchoACK following the SwapBuffers to be sent as close as
 779     // possible, avoiding scheduling other channels in the meantime.
 780     should_fast_track_ack = false;
 781     if (!deferred_messages_.empty()) {
 782       m = deferred_messages_.front();
 783       stub = stubs_.Lookup(m->routing_id());
 784       should_fast_track_ack =
 785           (m->type() == GpuCommandBufferMsg_Echo::ID) &&
 786           stub && stub->IsScheduled();
 787     }
 788   } while (should_fast_track_ack);
 789
 790   if (!deferred_messages_.empty()) {
 791     OnScheduled();
 792   }
 793 }
 794
 795 void GpuChannel::OnCreateOffscreenCommandBuffer(
 796     const gfx::Size& size,
 797     const GPUCreateCommandBufferConfig& init_params,
 798     int32* route_id) {
 799   TRACE_EVENT0("gpu", "GpuChannel::OnCreateOffscreenCommandBuffer");
 800   GpuCommandBufferStub* share_group = stubs_.Lookup(init_params.share_group_id);
 801
 802   *route_id = GenerateRouteID();
 803
 804   scoped_ptr<GpuCommandBufferStub> stub(new GpuCommandBufferStub(
 805       this,
 806       share_group,
 807       gfx::GLSurfaceHandle(),
 808       mailbox_manager_.get(),
 809       image_manager_.get(),
 810       size,
 811       disallowed_features_,
 812       init_params.attribs,
 813       init_params.gpu_preference,
 814       false,
 815       *route_id,
 816       0,
 817       watchdog_,
 818       software_,
 819       init_params.active_url));
 820   if (preempted_flag_.get())
 821     stub->SetPreemptByFlag(preempted_flag_);
 822   router_.AddRoute(*route_id, stub.get());
 823   stubs_.AddWithID(stub.release(), *route_id);
 824   TRACE_EVENT1("gpu", "GpuChannel::OnCreateOffscreenCommandBuffer",
 825                "route_id", route_id);
 826 }
 827
 828 void GpuChannel::OnDestroyCommandBuffer(int32 route_id) {
 829   TRACE_EVENT1("gpu", "GpuChannel::OnDestroyCommandBuffer",
 830                "route_id", route_id);
 831
 832   GpuCommandBufferStub* stub = stubs_.Lookup(route_id);
 833   if (!stub)
 834     return;
 835   bool need_reschedule = (stub && !stub->IsScheduled());
 836   router_.RemoveRoute(route_id);
 837   stubs_.Remove(route_id);
 838   // In case the renderer is currently blocked waiting for a sync reply from the
 839   // stub, we need to make sure to reschedule the GpuChannel here.
 840   if (need_reschedule) {
 841     // This stub won't get a chance to reschedule, so update the count now.
 842     StubSchedulingChanged(true);
 843   }
 844 }
 845
 846 void GpuChannel::OnCreateVideoEncoder(int32* route_id) {
 847   TRACE_EVENT0("gpu", "GpuChannel::OnCreateVideoEncoder");
 848
 849   *route_id = GenerateRouteID();
 850   GpuVideoEncodeAccelerator* encoder =
 851       new GpuVideoEncodeAccelerator(this, *route_id);
 852   router_.AddRoute(*route_id, encoder);
 853   video_encoders_.AddWithID(encoder, *route_id);
 854 }
 855
 856 void GpuChannel::OnDestroyVideoEncoder(int32 route_id) {
 857   TRACE_EVENT1(
 858       "gpu", "GpuChannel::OnDestroyVideoEncoder", "route_id", route_id);
 859   GpuVideoEncodeAccelerator* encoder = video_encoders_.Lookup(route_id);
 860   if (!encoder)
 861     return;
 862   router_.RemoveRoute(route_id);
 863   video_encoders_.Remove(route_id);
 864 }
 865
 866 void GpuChannel::OnDevToolsStartEventsRecording(int32* route_id) {
 867   devtools_gpu_agent_->StartEventsRecording(route_id);
 868 }
 869
 870 void GpuChannel::OnDevToolsStopEventsRecording() {
 871   devtools_gpu_agent_->StopEventsRecording();
 872 }
 873
 874 void GpuChannel::MessageProcessed() {
 875   messages_processed_++;
 876   if (preempting_flag_.get()) {
 877     io_message_loop_->PostTask(
 878         FROM_HERE,
 879         base::Bind(&GpuChannelMessageFilter::MessageProcessed,
 880                    filter_,
 881                    messages_processed_));
 882   }
 883 }
 884
 885 void GpuChannel::CacheShader(const std::string& key,
 886                              const std::string& shader) {
 887   gpu_channel_manager_->Send(
 888       new GpuHostMsg_CacheShader(client_id_, key, shader));
 889 }
 890
 891 void GpuChannel::AddFilter(IPC::ChannelProxy::MessageFilter* filter) {
 892   channel_->AddFilter(filter);
 893 }
 894
 895 void GpuChannel::RemoveFilter(IPC::ChannelProxy::MessageFilter* filter) {
 896   channel_->RemoveFilter(filter);
 897 }
 898
 899 }  // namespace content