cc: Add SchedulerStateMachine::DidDraw and use for forced draws

cc/scheduler/scheduler_state_machine.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_state_machine.h"
 
 #include "base/format_macros.h"
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
 #include "base/trace_event/trace_event.h"
@@ skipping 10 matching lines @@
 SchedulerStateMachine::SchedulerStateMachine(const SchedulerSettings& settings)
     : settings_(settings),
       output_surface_state_(OUTPUT_SURFACE_NONE),
       begin_impl_frame_state_(BEGIN_IMPL_FRAME_STATE_IDLE),
       begin_main_frame_state_(BEGIN_MAIN_FRAME_STATE_IDLE),
       forced_redraw_state_(FORCED_REDRAW_STATE_IDLE),
       commit_count_(0),
       current_frame_number_(0),
       last_frame_number_animate_performed_(-1),
       last_frame_number_swap_performed_(-1),
-      last_frame_number_swap_requested_(-1),
+      last_frame_number_draw_performed_(-1),
       last_frame_number_begin_main_frame_sent_(-1),
       last_frame_number_invalidate_output_surface_performed_(-1),
       animate_funnel_(false),
-      request_swap_funnel_(false),
+      draw_funnel_(false),
       send_begin_main_frame_funnel_(true),
       invalidate_output_surface_funnel_(false),
       prepare_tiles_funnel_(0),
       consecutive_checkerboard_animations_(0),
       pending_swaps_(0),
       swaps_with_current_output_surface_(0),
       needs_redraw_(false),
       needs_animate_(false),
       needs_prepare_tiles_(false),
       needs_begin_main_frame_(false),
       needs_one_begin_impl_frame_(false),
       visible_(false),
       resourceless_draw_(false),
       can_draw_(false),
       has_pending_tree_(false),
       pending_tree_is_ready_for_activation_(false),
       active_tree_needs_first_draw_(false),
       did_create_and_initialize_first_output_surface_(false),
       tree_priority_(NEW_CONTENT_TAKES_PRIORITY),
       scroll_handler_state_(
           ScrollHandlerState::SCROLL_DOES_NOT_AFFECT_SCROLL_HANDLER),
       critical_begin_main_frame_to_activate_is_fast_(true),
       main_thread_missed_last_deadline_(false),
       skip_next_begin_main_frame_to_reduce_latency_(false),
       children_need_begin_frames_(false),
       defer_commits_(false),
       video_needs_begin_frames_(false),
       last_commit_had_no_updates_(false),
       wait_for_ready_to_draw_(false),
-      did_request_swap_in_last_frame_(false),
-      did_perform_swap_in_last_draw_(false) {}
+      did_draw_in_last_frame_(false),
+      did_perform_swap_in_last_draw_(false),
+      last_draw_result_(INVALID_RESULT) {}
 
 const char* SchedulerStateMachine::OutputSurfaceStateToString(
     OutputSurfaceState state) {
   switch (state) {
     case OUTPUT_SURFACE_NONE:
       return "OUTPUT_SURFACE_NONE";
     case OUTPUT_SURFACE_ACTIVE:
       return "OUTPUT_SURFACE_ACTIVE";
     case OUTPUT_SURFACE_CREATING:
       return "OUTPUT_SURFACE_CREATING";
@@ skipping 138 matching lines @@
                    ForcedRedrawOnTimeoutStateToString(forced_redraw_state_));
   state->EndDictionary();
 
   state->BeginDictionary("minor_state");
   state->SetInteger("commit_count", commit_count_);
   state->SetInteger("current_frame_number", current_frame_number_);
   state->SetInteger("last_frame_number_animate_performed",
                     last_frame_number_animate_performed_);
   state->SetInteger("last_frame_number_swap_performed",
                     last_frame_number_swap_performed_);
-  state->SetInteger("last_frame_number_swap_requested",
-                    last_frame_number_swap_requested_);
+  state->SetInteger("last_frame_number_draw_performed",
+                    last_frame_number_draw_performed_);
   state->SetInteger("last_frame_number_begin_main_frame_sent",
                     last_frame_number_begin_main_frame_sent_);
   state->SetBoolean("funnel: animate_funnel", animate_funnel_);
-  state->SetBoolean("funnel: request_swap_funnel", request_swap_funnel_);
+  state->SetBoolean("funnel: draw_funnel", draw_funnel_);
   state->SetBoolean("funnel: send_begin_main_frame_funnel",
                     send_begin_main_frame_funnel_);
   state->SetInteger("funnel: prepare_tiles_funnel", prepare_tiles_funnel_);
   state->SetBoolean("funnel: invalidate_output_surface_funnel",
                     invalidate_output_surface_funnel_);
   state->SetInteger("consecutive_checkerboard_animations",
                     consecutive_checkerboard_animations_);
   state->SetInteger("pending_swaps_", pending_swaps_);
   state->SetInteger("swaps_with_current_output_surface",
                     swaps_with_current_output_surface_);
@@ skipping 19 matching lines @@
   state->SetBoolean("critical_begin_main_frame_to_activate_is_fast_",
                     critical_begin_main_frame_to_activate_is_fast_);
   state->SetBoolean("main_thread_missed_last_deadline",
                     main_thread_missed_last_deadline_);
   state->SetBoolean("skip_next_begin_main_frame_to_reduce_latency",
                     skip_next_begin_main_frame_to_reduce_latency_);
   state->SetBoolean("children_need_begin_frames", children_need_begin_frames_);
   state->SetBoolean("video_needs_begin_frames", video_needs_begin_frames_);
   state->SetBoolean("defer_commits", defer_commits_);
   state->SetBoolean("last_commit_had_no_updates", last_commit_had_no_updates_);
-  state->SetBoolean("did_request_swap_in_last_frame",
-                    did_request_swap_in_last_frame_);
+  state->SetBoolean("did_draw_in_last_frame", did_draw_in_last_frame_);
   state->SetBoolean("did_perform_swap_in_last_draw",
                     did_perform_swap_in_last_draw_);
   state->EndDictionary();
 }
 
 bool SchedulerStateMachine::PendingDrawsShouldBeAborted() const {
   // Normally when |visible_| is false, pending activations will be forced and
   // draws will be aborted. However, when the embedder is Android WebView,
   // software draws could be scheduled by the Android OS at any time and draws
   // should not be aborted in this case.
@@ skipping 61 matching lines @@
   // be blocking other important actions (like output surface initialization),
   // from occurring. If we are waiting for the first draw, then perform the
   // aborted draw to keep things moving. If we are not waiting for the first
   // draw however, we don't want to abort for no reason.
   if (PendingDrawsShouldBeAborted())
     return active_tree_needs_first_draw_;
 
   // Do not draw too many times in a single frame. It's okay that we don't check
   // this before checking for aborted draws because aborted draws do not request
   // a swap.
-  if (request_swap_funnel_)
+  if (draw_funnel_)
     return false;
 
   // Don't draw if we are waiting on the first commit after a surface.
   if (output_surface_state_ != OUTPUT_SURFACE_ACTIVE)
     return false;
 
   // Do not queue too many swaps.
   if (SwapThrottled())
     return false;
 
@@ skipping 297 matching lines @@
 
   if (forced_redraw_state_ == FORCED_REDRAW_STATE_WAITING_FOR_ACTIVATION)
     forced_redraw_state_ = FORCED_REDRAW_STATE_WAITING_FOR_DRAW;
 
   has_pending_tree_ = false;
   pending_tree_is_ready_for_activation_ = false;
   active_tree_needs_first_draw_ = true;
   needs_redraw_ = true;
 }
 
-void SchedulerStateMachine::WillDraw(bool did_request_swap) {
+void SchedulerStateMachine::WillDrawInternal() {
+  // We need to reset needs_redraw_ before we draw since the
+  // draw itself might request another draw.
+  needs_redraw_ = false;
+
+  draw_funnel_ = true;
+  active_tree_needs_first_draw_ = false;
+  did_draw_in_last_frame_ = true;
+  last_frame_number_draw_performed_ = current_frame_number_;
+
   if (forced_redraw_state_ == FORCED_REDRAW_STATE_WAITING_FOR_DRAW)
     forced_redraw_state_ = FORCED_REDRAW_STATE_IDLE;
 
   if (begin_main_frame_state_ == BEGIN_MAIN_FRAME_STATE_WAITING_FOR_DRAW)
     begin_main_frame_state_ = BEGIN_MAIN_FRAME_STATE_IDLE;
+}
 
-  needs_redraw_ = false;
-  active_tree_needs_first_draw_ = false;
+void SchedulerStateMachine::DidDrawInternal(DrawResult draw_result) {
+  switch (draw_result) {
+    case INVALID_RESULT:
+    case DRAW_ABORTED_CANT_DRAW:
+    case DRAW_ABORTED_CONTEXT_LOST:
+      NOTREACHED() << "Invalid return DrawResult:" << draw_result;
+      break;
+    case DRAW_ABORTED_DRAINING_PIPELINE:

[sunnyps, 2015/11/24 22:42:44]

nit: Maybe DCHECK(!did_perform_swap_in_last_draw_) here too.

[brianderson, 2015/11/24 23:19:38]

Tried doing this. DRAW_ABORTED_DRAINING_PIPELINE can come in at anytime compared
to the other aborts which only arrive in the deadline, so the DCHECK doesn't
quite work. I added a comment.

+    case DRAW_SUCCESS:
+      consecutive_checkerboard_animations_ = 0;
+      forced_redraw_state_ = FORCED_REDRAW_STATE_IDLE;
+      break;
+    case DRAW_ABORTED_CHECKERBOARD_ANIMATIONS:
+      DCHECK(!did_perform_swap_in_last_draw_);
+      needs_begin_main_frame_ = true;
+      needs_redraw_ = true;
+      consecutive_checkerboard_animations_++;
 
-  if (did_request_swap) {
-    DCHECK(!request_swap_funnel_);
-    request_swap_funnel_ = true;
-    did_request_swap_in_last_frame_ = true;
-    last_frame_number_swap_requested_ = current_frame_number_;
+      if (consecutive_checkerboard_animations_ >=
+              settings_.maximum_number_of_failed_draws_before_draw_is_forced &&
+          forced_redraw_state_ == FORCED_REDRAW_STATE_IDLE &&
+          settings_.timeout_and_draw_when_animation_checkerboards) {
+        // We need to force a draw, but it doesn't make sense to do this until
+        // we've committed and have new textures.
+        forced_redraw_state_ = FORCED_REDRAW_STATE_WAITING_FOR_COMMIT;
+      }
+      break;
+    case DRAW_ABORTED_MISSING_HIGH_RES_CONTENT:
+      DCHECK(!did_perform_swap_in_last_draw_);
+      // It's not clear whether this missing content is because of missing
+      // pictures (which requires a commit) or because of memory pressure
+      // removing textures (which might not).  To be safe, request a commit
+      // anyway.
+      needs_begin_main_frame_ = true;
+      break;
   }
+  last_draw_result_ = draw_result;
+}
+
+void SchedulerStateMachine::WillDraw() {
+  DCHECK(!draw_funnel_);
+  WillDrawInternal();
+
+  // Assume the draw will succeed in case we get a DidSwapBuffers
+  // before DidDraw is called.
+  last_draw_result_ = DRAW_SUCCESS;

[sunnyps, 2015/11/24 22:42:44]

nit: Looks like the only reason to set this is for the DCHECK in DidSwapBuffers.
Seems unnecessary.

[brianderson, 2015/11/24 23:19:38]

True. Removed.

+}
+
+void SchedulerStateMachine::DidDraw(DrawResult draw_result) {
+  DidDrawInternal(draw_result);
+}
+
+void SchedulerStateMachine::AbortDrawAndSwap() {
+  // Pretend like the draw was successful.
+  WillDrawInternal();
+  DidDrawInternal(DRAW_ABORTED_DRAINING_PIPELINE);
 }
 
 void SchedulerStateMachine::WillPrepareTiles() {
   needs_prepare_tiles_ = false;
 }
 
 void SchedulerStateMachine::WillBeginOutputSurfaceCreation() {
   DCHECK_EQ(output_surface_state_, OUTPUT_SURFACE_NONE);
   output_surface_state_ = OUTPUT_SURFACE_CREATING;
 
@@ skipping 95 matching lines @@
   // If the pending tree activates quickly, we'll want a BeginImplFrame soon
   // to draw the new active tree.
   if (has_pending_tree_)
     return true;
 
   // Changing priorities may allow us to activate (given the new priorities),
   // which may result in a new frame.
   if (needs_prepare_tiles_)
     return true;
 
-  // If we just sent a swap request, it's likely that we are going to produce
+  // If we just tried to DrawAndSwap, it's likely that we are going to produce
   // another frame soon. This helps avoid negative glitches in our
   // SetNeedsBeginFrame requests, which may propagate to the BeginImplFrame
   // provider and get sampled at an inopportune time, delaying the next
   // BeginImplFrame.
-  if (did_request_swap_in_last_frame_)
+  if (did_draw_in_last_frame_)
     return true;
 
   // If the last commit was aborted because of early out (no updates), we should
   // still want a begin frame in case there is a commit coming again.
   if (last_commit_had_no_updates_)
     return true;
 
   return false;
 }
 
 void SchedulerStateMachine::OnBeginImplFrame() {
   begin_impl_frame_state_ = BEGIN_IMPL_FRAME_STATE_BEGIN_FRAME_STARTING;
   current_frame_number_++;
 
   last_commit_had_no_updates_ = false;
-  did_request_swap_in_last_frame_ = false;
+  did_draw_in_last_frame_ = false;
   needs_one_begin_impl_frame_ = false;
 
   // Clear funnels for any actions we perform during the frame.
   animate_funnel_ = false;
   send_begin_main_frame_funnel_ = false;
   invalidate_output_surface_funnel_ = false;
 
   // "Drain" the PrepareTiles funnel.
   if (prepare_tiles_funnel_ > 0)
     prepare_tiles_funnel_--;
 }
 
 void SchedulerStateMachine::OnBeginImplFrameDeadlinePending() {
   begin_impl_frame_state_ = BEGIN_IMPL_FRAME_STATE_INSIDE_BEGIN_FRAME;
 }
 
 void SchedulerStateMachine::OnBeginImplFrameDeadline() {
   begin_impl_frame_state_ = BEGIN_IMPL_FRAME_STATE_INSIDE_DEADLINE;
 
   did_perform_swap_in_last_draw_ = false;
 
   // Clear funnels for any actions we perform during the deadline.
-  request_swap_funnel_ = false;
+  draw_funnel_ = false;
 
   // Allow one PrepareTiles per draw for synchronous compositor.
   if (settings_.using_synchronous_renderer_compositor) {
     if (prepare_tiles_funnel_ > 0)
       prepare_tiles_funnel_--;
   }
 }
 
 void SchedulerStateMachine::OnBeginImplFrameIdle() {
   begin_impl_frame_state_ = BEGIN_IMPL_FRAME_STATE_IDLE;
@@ skipping 115 matching lines @@
 }
 
 void SchedulerStateMachine::SetNeedsPrepareTiles() {
   if (!needs_prepare_tiles_) {
     TRACE_EVENT0("cc", "SchedulerStateMachine::SetNeedsPrepareTiles");
     needs_prepare_tiles_ = true;
   }
 }
 void SchedulerStateMachine::DidSwapBuffers() {
   TRACE_EVENT_ASYNC_BEGIN0("cc", "Scheduler:pending_swaps", this);
+  DCHECK_EQ(last_draw_result_, DRAW_SUCCESS);

[sunnyps, 2015/11/24 22:42:44]

nit: This DCHECK_EQ should be unnecessary.

[brianderson, 2015/11/24 23:19:38]

Done.

+  DCHECK_LT(pending_swaps_, kMaxPendingSwaps);
+
   pending_swaps_++;
   swaps_with_current_output_surface_++;
 
-  DCHECK_LE(pending_swaps_, kMaxPendingSwaps);
-
   did_perform_swap_in_last_draw_ = true;
   last_frame_number_swap_performed_ = current_frame_number_;
 }
 
 void SchedulerStateMachine::DidSwapBuffersComplete() {
   TRACE_EVENT_ASYNC_END0("cc", "Scheduler:pending_swaps", this);
   pending_swaps_--;
 }
 
 void SchedulerStateMachine::SetTreePrioritiesAndScrollState(
@@ skipping 16 matching lines @@
       critical_begin_main_frame_to_activate_is_fast_)
     return false;
 
   // Don't wait for the main thread if we are prioritizing smoothness.
   if (SMOOTHNESS_TAKES_PRIORITY == tree_priority_)
     return true;
 
   return false;
 }
 
-void SchedulerStateMachine::DidDrawIfPossibleCompleted(DrawResult result) {
-  switch (result) {
-    case INVALID_RESULT:
-      NOTREACHED() << "Uninitialized DrawResult.";
-      break;
-    case DRAW_ABORTED_CANT_DRAW:
-    case DRAW_ABORTED_CONTEXT_LOST:
-      NOTREACHED() << "Invalid return value from DrawAndSwapIfPossible:"
-                   << result;
-      break;
-    case DRAW_SUCCESS:
-      consecutive_checkerboard_animations_ = 0;
-      forced_redraw_state_ = FORCED_REDRAW_STATE_IDLE;
-      break;
-    case DRAW_ABORTED_CHECKERBOARD_ANIMATIONS:
-      needs_redraw_ = true;
-
-      // If we're already in the middle of a redraw, we don't need to
-      // restart it.
-      if (forced_redraw_state_ != FORCED_REDRAW_STATE_IDLE)
-        return;
-
-      needs_begin_main_frame_ = true;
-      consecutive_checkerboard_animations_++;
-      if (settings_.timeout_and_draw_when_animation_checkerboards &&
-          consecutive_checkerboard_animations_ >=
-              settings_.maximum_number_of_failed_draws_before_draw_is_forced) {
-        consecutive_checkerboard_animations_ = 0;
-        // We need to force a draw, but it doesn't make sense to do this until
-        // we've committed and have new textures.
-        forced_redraw_state_ = FORCED_REDRAW_STATE_WAITING_FOR_COMMIT;
-      }
-      break;
-    case DRAW_ABORTED_MISSING_HIGH_RES_CONTENT:
-      // It's not clear whether this missing content is because of missing
-      // pictures (which requires a commit) or because of memory pressure
-      // removing textures (which might not).  To be safe, request a commit
-      // anyway.
-      needs_begin_main_frame_ = true;
-      break;
-  }
-}
-
 void SchedulerStateMachine::SetNeedsBeginMainFrame() {
   needs_begin_main_frame_ = true;
 }
 
 void SchedulerStateMachine::SetNeedsOneBeginImplFrame() {
   needs_one_begin_impl_frame_ = true;
 }
 
 void SchedulerStateMachine::NotifyReadyToCommit() {
   DCHECK_EQ(begin_main_frame_state_, BEGIN_MAIN_FRAME_STATE_STARTED)
@@ skipping 75 matching lines @@
     case OUTPUT_SURFACE_ACTIVE:
     case OUTPUT_SURFACE_WAITING_FOR_FIRST_COMMIT:
     case OUTPUT_SURFACE_WAITING_FOR_FIRST_ACTIVATION:
       return true;
   }
   NOTREACHED();
   return false;
 }
 
 }  // namespace cc