cc: Use BeginFrameArgs

cc/scheduler/scheduler.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/scheduler/scheduler.h"
 
+#include <algorithm>
 #include "base/auto_reset.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 
 namespace cc {
 
 Scheduler::Scheduler(SchedulerClient* client,
                      const SchedulerSettings& scheduler_settings)
     : settings_(scheduler_settings),
       client_(client),
       weak_factory_(this),
       last_set_needs_begin_frame_(false),
       has_pending_begin_frame_(false),
-      safe_to_expect_begin_frame_(false),
+      safe_to_expect_begin_frame_(
+        !scheduler_settings.use_begin_frame_workaround_for_crbug_249806),
       state_machine_(scheduler_settings),
       inside_process_scheduled_actions_(false) {
   DCHECK(client_);
-  DCHECK(!state_machine_.BeginFrameNeededToDrawByImplThread());
+  DCHECK(!state_machine_.BeginFrameNeededByImplThread());
 }
 
 Scheduler::~Scheduler() {
   client_->SetNeedsBeginFrameOnImplThread(false);
 }
 
 void Scheduler::SetCanStart() {
   state_machine_.SetCanStart();
   ProcessScheduledActions();
 }
 
 void Scheduler::SetVisible(bool visible) {
   state_machine_.SetVisible(visible);
   ProcessScheduledActions();
 }
 
 void Scheduler::SetCanDraw(bool can_draw) {
   state_machine_.SetCanDraw(can_draw);
   ProcessScheduledActions();
 }
 
-void Scheduler::SetHasPendingTree(bool has_pending_tree) {
-  state_machine_.SetHasPendingTree(has_pending_tree);
+void Scheduler::NotifyReadyToActivate() {
+  state_machine_.NotifyReadyToActivate();
   ProcessScheduledActions();
 }
 
+void Scheduler::SetHasTrees(bool has_pending_tree, bool active_tree_is_null) {
+  state_machine_.SetHasTrees(has_pending_tree, active_tree_is_null);
+  ProcessScheduledActions();
+
+  if (state_machine_.ShouldTriggerBeginFrameDeadlineEarly())
+    PostBeginFrameDeadline(base::TimeTicks());
+}
+
 void Scheduler::SetNeedsCommit() {
   state_machine_.SetNeedsCommit();
   ProcessScheduledActions();
 }
 
-void Scheduler::SetNeedsForcedCommit() {
+void Scheduler::SetNeedsForcedCommitForReadback() {
   state_machine_.SetNeedsCommit();
-  state_machine_.SetNeedsForcedCommit();
+  state_machine_.SetNeedsForcedCommitForReadback();
   ProcessScheduledActions();
 }
 
 void Scheduler::SetNeedsRedraw() {
   state_machine_.SetNeedsRedraw();
   ProcessScheduledActions();
 }
 
 void Scheduler::DidSwapUseIncompleteTile() {
   state_machine_.DidSwapUseIncompleteTile();
   ProcessScheduledActions();
 }
 
-void Scheduler::SetNeedsForcedRedraw() {
-  state_machine_.SetNeedsForcedRedraw();
-  ProcessScheduledActions();
-}
-
 void Scheduler::SetMainThreadNeedsLayerTextures() {
   state_machine_.SetMainThreadNeedsLayerTextures();
   ProcessScheduledActions();
 }
 
 void Scheduler::FinishCommit() {
   TRACE_EVENT0("cc", "Scheduler::FinishCommit");
   state_machine_.FinishCommit();
   ProcessScheduledActions();
+
+  if (state_machine_.ShouldTriggerBeginFrameDeadlineEarly())
+    PostBeginFrameDeadline(base::TimeTicks());
 }
 
 void Scheduler::BeginFrameAbortedByMainThread(bool did_handle) {
   TRACE_EVENT0("cc", "Scheduler::BeginFrameAbortedByMainThread");
   state_machine_.BeginFrameAbortedByMainThread(did_handle);
   ProcessScheduledActions();
 }
 
 void Scheduler::DidLoseOutputSurface() {
   TRACE_EVENT0("cc", "Scheduler::DidLoseOutputSurface");
+  begin_frame_deadline_closure_.Cancel();
+  has_pending_begin_frame_ = false;
   state_machine_.DidLoseOutputSurface();
   ProcessScheduledActions();
 }
 
 void Scheduler::DidCreateAndInitializeOutputSurface() {
   TRACE_EVENT0("cc", "Scheduler::DidCreateAndInitializeOutputSurface");
   state_machine_.DidCreateAndInitializeOutputSurface();
+  begin_frame_deadline_closure_.Cancel();
   has_pending_begin_frame_ = false;
   last_set_needs_begin_frame_ = false;
-  safe_to_expect_begin_frame_ = false;
+  safe_to_expect_begin_frame_ =
+      !settings_.use_begin_frame_workaround_for_crbug_249806;
   ProcessScheduledActions();
 }
 
 base::TimeTicks Scheduler::AnticipatedDrawTime() {
   TRACE_EVENT0("cc", "Scheduler::AnticipatedDrawTime");
 
   if (!last_set_needs_begin_frame_ ||
       last_begin_frame_args_.interval <= base::TimeDelta())
     return base::TimeTicks();
 
-  // TODO(brianderson): Express this in terms of the deadline.
   base::TimeTicks now = base::TimeTicks::Now();
-  int64 intervals = 1 + ((now - last_begin_frame_args_.frame_time) /
-                         last_begin_frame_args_.interval);
-  return last_begin_frame_args_.frame_time +
-      (last_begin_frame_args_.interval * intervals);
+  base::TimeTicks timebase = std::max(last_begin_frame_args_.frame_time,
+                                      last_begin_frame_args_.deadline);
+  int64 intervals = 1 + ((now - timebase) / last_begin_frame_args_.interval);
+  return timebase + (last_begin_frame_args_.interval * intervals);
 }
 
 base::TimeTicks Scheduler::LastBeginFrameOnImplThreadTime() {
   return last_begin_frame_args_.frame_time;
 }
 
 void Scheduler::SetupNextBeginFrameIfNeeded() {
   bool needs_begin_frame_to_draw =
       state_machine_.BeginFrameNeededToDrawByImplThread();
-  // We want to avoid proactive begin frames with the synchronous compositor
-  // because every SetNeedsBeginFrame will force a redraw.
   bool proactive_begin_frame_wanted =
-      state_machine_.ProactiveBeginFrameWantedByImplThread() &&
-      !settings_.using_synchronous_renderer_compositor &&
-      settings_.throttle_frame_production;
+      state_machine_.BeginFrameProactivelyNeededByImplThread();
+
+  // We want to avoid proactive begin frames with the synchronous
+  // compositor because every SetNeedsBeginFrame will force a redraw.
   bool needs_begin_frame = needs_begin_frame_to_draw ||
                            proactive_begin_frame_wanted;
-  bool immediate_disables_needed =
-      settings_.using_synchronous_renderer_compositor;
+
+  bool should_call_set_needs_begin_frame =
+      // The synchronous renderer compositor needs immediate enables/disables.
+      (settings_.using_synchronous_renderer_compositor &&
+       needs_begin_frame != last_set_needs_begin_frame_) ||
+      // Always request the BeginFrame immediately if it wasn't needed before.
+      (needs_begin_frame && !last_set_needs_begin_frame_) ||
+      // Only disable the BeginFrame after a BeginFrame where we didn't swap.
+      (!needs_begin_frame && last_set_needs_begin_frame_ &&
+       has_pending_begin_frame_ && !state_machine_.InsideBeginFrame()) ||
+      // We did not draw and swap this BeginFrame,
+      // so we need to explicitly request another BeginFrame.
+      (needs_begin_frame && has_pending_begin_frame_ &&
+       !state_machine_.InsideBeginFrame());
 
   if (needs_begin_frame_to_draw)
     safe_to_expect_begin_frame_ = true;
 
-  // Determine if we need BeginFrame notifications.
-  // If we do, always request the BeginFrame immediately.
-  // If not, only disable on the next BeginFrame to avoid unnecessary toggles.
-  // The synchronous renderer compositor requires immediate disables though.
-  if ((needs_begin_frame ||
-       state_machine_.inside_begin_frame() ||
-       immediate_disables_needed) &&
-      (needs_begin_frame != last_set_needs_begin_frame_)) {
+  if (should_call_set_needs_begin_frame) {
     has_pending_begin_frame_ = false;
     client_->SetNeedsBeginFrameOnImplThread(needs_begin_frame);
     if (safe_to_expect_begin_frame_)
       last_set_needs_begin_frame_ = needs_begin_frame;
   }
-
-  // Request another BeginFrame if we haven't drawn for now until we have
-  // deadlines implemented.
-  if (state_machine_.inside_begin_frame() && has_pending_begin_frame_) {
-    has_pending_begin_frame_ = false;
-    client_->SetNeedsBeginFrameOnImplThread(true);
-    return;
-  }
 }
 
 void Scheduler::BeginFrame(const BeginFrameArgs& args) {
   TRACE_EVENT0("cc", "Scheduler::BeginFrame");
   DCHECK(!has_pending_begin_frame_);
   has_pending_begin_frame_ = true;
   safe_to_expect_begin_frame_ = true;
   last_begin_frame_args_ = args;
-  state_machine_.DidEnterBeginFrame(args);
+  last_begin_frame_args_.AdjustDeadline(-client_->DrawDurationEstimate());
+  state_machine_.OnBeginFrame(last_begin_frame_args_);
   ProcessScheduledActions();
-  state_machine_.DidLeaveBeginFrame();
+
+  if (settings_.using_synchronous_renderer_compositor)
+    OnBeginFrameDeadline();
+  else if (state_machine_.ShouldTriggerBeginFrameDeadlineEarly()) {
+    // We are ready to draw a new active tree immediately.
+    PostBeginFrameDeadline(base::TimeTicks());
+  } else if (state_machine_.needs_redraw()) {
+    // We have an animation or fast input path on the impl thread that wants
+    // to draw, so don't wait too long for a new active tree.
+    PostBeginFrameDeadline(last_begin_frame_args_.deadline);
+  } else {
+    // The impl thread doesn't have anything it wants to draw and we are just
+    // waiting for a new active tree, so post the deadline for the next
+    // expected BeginFrame start.
+    PostBeginFrameDeadline(last_begin_frame_args_.frame_time +
+                           last_begin_frame_args_.interval);
+  }
+}
+
+void Scheduler::PostBeginFrameDeadline(base::TimeTicks deadline) {
+  begin_frame_deadline_closure_.Cancel();
+  begin_frame_deadline_closure_.Reset(
+      base::Bind(&Scheduler::OnBeginFrameDeadline, weak_factory_.GetWeakPtr()));
+  client_->PostBeginFrameDeadline(
+      begin_frame_deadline_closure_.callback(), deadline);
+}
+
+void Scheduler::OnBeginFrameDeadline() {
+  TRACE_EVENT0("cc", "Scheduler::OnBeginFrameDeadline");
+  begin_frame_deadline_closure_.Cancel();
+  state_machine_.OnBeginFrameDeadline();
+  ProcessScheduledActions();
+  client_->DidBeginFrameDeadlineOnImplThread();
 }
 
 void Scheduler::DrawAndSwapIfPossible() {
-  ScheduledActionDrawAndSwapResult result =
+  DrawSwapReadbackResult result =
       client_->ScheduledActionDrawAndSwapIfPossible();
   state_machine_.DidDrawIfPossibleCompleted(result.did_draw);
   if (result.did_swap)
     has_pending_begin_frame_ = false;
 }
 
 void Scheduler::DrawAndSwapForced() {
-  ScheduledActionDrawAndSwapResult result =
+  DrawSwapReadbackResult result =
       client_->ScheduledActionDrawAndSwapForced();
   if (result.did_swap)
     has_pending_begin_frame_ = false;
 }
 
 void Scheduler::ProcessScheduledActions() {
   // We do not allow ProcessScheduledActions to be recursive.
   // The top-level call will iteratively execute the next action for us anyway.
   if (inside_process_scheduled_actions_)
     return;
 
   base::AutoReset<bool> mark_inside(&inside_process_scheduled_actions_, true);
 
-  SchedulerStateMachine::Action action = state_machine_.NextAction();
-  while (action != SchedulerStateMachine::ACTION_NONE) {
+  SchedulerStateMachine::Action action;
+  do {
+    action = state_machine_.NextAction();
+    TRACE_EVENT2("cc", "SchedulerStateMachine",
+                 "action", action,
+                 "state", state_machine_.ToString());
     state_machine_.UpdateState(action);
     switch (action) {
       case SchedulerStateMachine::ACTION_NONE:
         break;
       case SchedulerStateMachine::ACTION_SEND_BEGIN_FRAME_TO_MAIN_THREAD:
         client_->ScheduledActionSendBeginFrameToMainThread();
         break;
       case SchedulerStateMachine::ACTION_COMMIT:
         client_->ScheduledActionCommit();
         break;
       case SchedulerStateMachine::ACTION_UPDATE_VISIBLE_TILES:
         client_->ScheduledActionUpdateVisibleTiles();
         break;
-      case SchedulerStateMachine::ACTION_ACTIVATE_PENDING_TREE_IF_NEEDED:
-        client_->ScheduledActionActivatePendingTreeIfNeeded();
+      case SchedulerStateMachine::ACTION_ACTIVATE_PENDING_TREE:
+        client_->ScheduledActionActivatePendingTree();
         break;
-      case SchedulerStateMachine::ACTION_DRAW_IF_POSSIBLE:
+      case SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE:
         DrawAndSwapIfPossible();
         break;
-      case SchedulerStateMachine::ACTION_DRAW_FORCED:
+      case SchedulerStateMachine::ACTION_DRAW_AND_SWAP_FORCED:
         DrawAndSwapForced();
         break;
+      case SchedulerStateMachine::ACTION_DRAW_AND_SWAP_ABORT:
+        // No action is actually performed, but this allows the state machine to
+        // advance out of its waiting to draw state without actually drawing.
+        break;
+      case SchedulerStateMachine::ACTION_DRAW_AND_READBACK:
+        client_->ScheduledActionDrawAndReadback();
+        break;
       case SchedulerStateMachine::ACTION_BEGIN_OUTPUT_SURFACE_CREATION:
         client_->ScheduledActionBeginOutputSurfaceCreation();
         break;
       case SchedulerStateMachine::ACTION_ACQUIRE_LAYER_TEXTURES_FOR_MAIN_THREAD:
         client_->ScheduledActionAcquireLayerTexturesForMainThread();
         break;
     }
-    action = state_machine_.NextAction();
-  }
+  } while (action != SchedulerStateMachine::ACTION_NONE);
 
+  state_machine_.AdvanceBeginFrameStateWhenNoActionsRemain();
   SetupNextBeginFrameIfNeeded();
   client_->DidAnticipatedDrawTimeChange(AnticipatedDrawTime());
 }
 
 bool Scheduler::WillDrawIfNeeded() const {
   return !state_machine_.DrawSuspendedUntilCommit();
 }
 
 }  // namespace cc