| // 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/logging.h" |
| #include "base/memory/ptr_util.h" |
| #include "base/single_thread_task_runner.h" |
| #include "base/trace_event/trace_event.h" |
| #include "base/trace_event/trace_event_argument.h" |
| #include "cc/base/devtools_instrumentation.h" |
| #include "cc/scheduler/compositor_timing_history.h" |
| #include "components/viz/common/frame_sinks/delay_based_time_source.h" |
| |
| namespace cc { |
| |
| namespace { |
| // This is a fudge factor we subtract from the deadline to account |
| // for message latency and kernel scheduling variability. |
| const base::TimeDelta kDeadlineFudgeFactor = |
| base::TimeDelta::FromMicroseconds(1000); |
| } // namespace |
| |
| Scheduler::Scheduler( |
| SchedulerClient* client, |
| const SchedulerSettings& settings, |
| int layer_tree_host_id, |
| base::SingleThreadTaskRunner* task_runner, |
| std::unique_ptr<CompositorTimingHistory> compositor_timing_history) |
| : settings_(settings), |
| client_(client), |
| layer_tree_host_id_(layer_tree_host_id), |
| task_runner_(task_runner), |
| compositor_timing_history_(std::move(compositor_timing_history)), |
| begin_impl_frame_tracker_(BEGINFRAMETRACKER_FROM_HERE), |
| state_machine_(settings), |
| weak_factory_(this) { |
| TRACE_EVENT1("cc", "Scheduler::Scheduler", "settings", settings_.AsValue()); |
| DCHECK(client_); |
| DCHECK(!state_machine_.BeginFrameNeeded()); |
| |
| begin_impl_frame_deadline_closure_ = base::Bind( |
| &Scheduler::OnBeginImplFrameDeadline, weak_factory_.GetWeakPtr()); |
| |
| // We want to handle animate_only BeginFrames. |
| wants_animate_only_begin_frames_ = true; |
| |
| ProcessScheduledActions(); |
| } |
| |
| Scheduler::~Scheduler() { |
| SetBeginFrameSource(nullptr); |
| } |
| |
| void Scheduler::Stop() { |
| stopped_ = true; |
| } |
| |
| void Scheduler::SetNeedsImplSideInvalidation( |
| bool needs_first_draw_on_activation) { |
| state_machine_.SetNeedsImplSideInvalidation(needs_first_draw_on_activation); |
| ProcessScheduledActions(); |
| } |
| |
| base::TimeTicks Scheduler::Now() const { |
| base::TimeTicks now = base::TimeTicks::Now(); |
| TRACE_EVENT1(TRACE_DISABLED_BY_DEFAULT("cc.debug.scheduler.now"), |
| "Scheduler::Now", "now", now); |
| return now; |
| } |
| |
| void Scheduler::SetVisible(bool visible) { |
| state_machine_.SetVisible(visible); |
| UpdateCompositorTimingHistoryRecordingEnabled(); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::SetCanDraw(bool can_draw) { |
| state_machine_.SetCanDraw(can_draw); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::NotifyReadyToActivate() { |
| if (state_machine_.NotifyReadyToActivate()) |
| compositor_timing_history_->ReadyToActivate(); |
| |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::NotifyReadyToDraw() { |
| // Future work might still needed for crbug.com/352894. |
| state_machine_.NotifyReadyToDraw(); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::SetBeginFrameSource(viz::BeginFrameSource* source) { |
| if (source == begin_frame_source_) |
| return; |
| if (begin_frame_source_ && observing_begin_frame_source_) |
| begin_frame_source_->RemoveObserver(this); |
| begin_frame_source_ = source; |
| if (!begin_frame_source_) |
| return; |
| if (observing_begin_frame_source_) |
| begin_frame_source_->AddObserver(this); |
| } |
| |
| void Scheduler::SetNeedsBeginMainFrame() { |
| state_machine_.SetNeedsBeginMainFrame(); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::SetNeedsOneBeginImplFrame() { |
| state_machine_.SetNeedsOneBeginImplFrame(); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::SetNeedsRedraw() { |
| state_machine_.SetNeedsRedraw(); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::SetNeedsPrepareTiles() { |
| DCHECK(!IsInsideAction(SchedulerStateMachine::Action::PREPARE_TILES)); |
| state_machine_.SetNeedsPrepareTiles(); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::DidSubmitCompositorFrame() { |
| compositor_timing_history_->DidSubmitCompositorFrame(); |
| state_machine_.DidSubmitCompositorFrame(); |
| |
| // There is no need to call ProcessScheduledActions here because |
| // submitting a CompositorFrame should not trigger any new actions. |
| if (!inside_process_scheduled_actions_) { |
| DCHECK_EQ(state_machine_.NextAction(), SchedulerStateMachine::Action::NONE); |
| } |
| } |
| |
| void Scheduler::DidReceiveCompositorFrameAck() { |
| DCHECK_GT(state_machine_.pending_submit_frames(), 0) << AsValue()->ToString(); |
| compositor_timing_history_->DidReceiveCompositorFrameAck(); |
| state_machine_.DidReceiveCompositorFrameAck(); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::SetTreePrioritiesAndScrollState( |
| TreePriority tree_priority, |
| ScrollHandlerState scroll_handler_state) { |
| compositor_timing_history_->SetTreePriority(tree_priority); |
| state_machine_.SetTreePrioritiesAndScrollState(tree_priority, |
| scroll_handler_state); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::NotifyReadyToCommit() { |
| TRACE_EVENT0("cc", "Scheduler::NotifyReadyToCommit"); |
| compositor_timing_history_->NotifyReadyToCommit(); |
| state_machine_.NotifyReadyToCommit(); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::DidCommit() { |
| compositor_timing_history_->DidCommit(); |
| } |
| |
| void Scheduler::BeginMainFrameAborted(CommitEarlyOutReason reason) { |
| TRACE_EVENT1("cc", "Scheduler::BeginMainFrameAborted", "reason", |
| CommitEarlyOutReasonToString(reason)); |
| compositor_timing_history_->BeginMainFrameAborted(); |
| state_machine_.BeginMainFrameAborted(reason); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::WillPrepareTiles() { |
| compositor_timing_history_->WillPrepareTiles(); |
| } |
| |
| void Scheduler::DidPrepareTiles() { |
| compositor_timing_history_->DidPrepareTiles(); |
| state_machine_.DidPrepareTiles(); |
| } |
| |
| void Scheduler::DidLoseLayerTreeFrameSink() { |
| TRACE_EVENT0("cc", "Scheduler::DidLoseLayerTreeFrameSink"); |
| state_machine_.DidLoseLayerTreeFrameSink(); |
| UpdateCompositorTimingHistoryRecordingEnabled(); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::DidCreateAndInitializeLayerTreeFrameSink() { |
| TRACE_EVENT0("cc", "Scheduler::DidCreateAndInitializeLayerTreeFrameSink"); |
| DCHECK(!observing_begin_frame_source_); |
| DCHECK(begin_impl_frame_deadline_task_.IsCancelled()); |
| state_machine_.DidCreateAndInitializeLayerTreeFrameSink(); |
| compositor_timing_history_->DidCreateAndInitializeLayerTreeFrameSink(); |
| UpdateCompositorTimingHistoryRecordingEnabled(); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::NotifyBeginMainFrameStarted( |
| base::TimeTicks main_thread_start_time) { |
| TRACE_EVENT0("cc", "Scheduler::NotifyBeginMainFrameStarted"); |
| state_machine_.NotifyBeginMainFrameStarted(); |
| compositor_timing_history_->BeginMainFrameStarted(main_thread_start_time); |
| } |
| |
| base::TimeTicks Scheduler::LastBeginImplFrameTime() { |
| return begin_impl_frame_tracker_.Current().frame_time; |
| } |
| |
| void Scheduler::BeginMainFrameNotExpectedUntil(base::TimeTicks time) { |
| TRACE_EVENT1("cc", "Scheduler::BeginMainFrameNotExpectedUntil", |
| "remaining_time", (time - Now()).InMillisecondsF()); |
| |
| DCHECK(!inside_scheduled_action_); |
| base::AutoReset<bool> mark_inside(&inside_scheduled_action_, true); |
| client_->ScheduledActionBeginMainFrameNotExpectedUntil(time); |
| } |
| |
| void Scheduler::BeginImplFrameNotExpectedSoon() { |
| compositor_timing_history_->BeginImplFrameNotExpectedSoon(); |
| |
| // Tying this to SendBeginMainFrameNotExpectedSoon will have some |
| // false negatives, but we want to avoid running long idle tasks when |
| // we are actually active. |
| if (state_machine_.wants_begin_main_frame_not_expected_messages()) { |
| DCHECK(!inside_scheduled_action_); |
| base::AutoReset<bool> mark_inside(&inside_scheduled_action_, true); |
| client_->SendBeginMainFrameNotExpectedSoon(); |
| } |
| } |
| |
| void Scheduler::SetupNextBeginFrameIfNeeded() { |
| if (state_machine_.begin_impl_frame_state() != |
| SchedulerStateMachine::BeginImplFrameState::IDLE) { |
| return; |
| } |
| |
| bool needs_begin_frames = state_machine_.BeginFrameNeeded(); |
| |
| // The propagation of the needsBeginFrame signal to viz is inherently racy |
| // with issuing the next BeginFrame. In full-pipe mode, it is important we |
| // don't miss a BeginFrame because our needsBeginFrames signal propagated to |
| // viz too slowly. To avoid the race, we simply always request BeginFrames |
| // from viz. |
| if (settings_.wait_for_all_pipeline_stages_before_draw && |
| state_machine_.HasInitializedLayerTreeFrameSink()) { |
| needs_begin_frames = true; |
| } |
| |
| if (needs_begin_frames && !observing_begin_frame_source_) { |
| observing_begin_frame_source_ = true; |
| if (begin_frame_source_) |
| begin_frame_source_->AddObserver(this); |
| devtools_instrumentation::NeedsBeginFrameChanged(layer_tree_host_id_, true); |
| } else if (!needs_begin_frames && observing_begin_frame_source_) { |
| observing_begin_frame_source_ = false; |
| if (begin_frame_source_) |
| begin_frame_source_->RemoveObserver(this); |
| missed_begin_frame_task_.Cancel(); |
| BeginImplFrameNotExpectedSoon(); |
| devtools_instrumentation::NeedsBeginFrameChanged(layer_tree_host_id_, |
| false); |
| } |
| } |
| |
| void Scheduler::OnBeginFrameSourcePausedChanged(bool paused) { |
| if (state_machine_.begin_frame_source_paused() == paused) |
| return; |
| TRACE_EVENT_INSTANT1("cc", "Scheduler::SetBeginFrameSourcePaused", |
| TRACE_EVENT_SCOPE_THREAD, "paused", paused); |
| state_machine_.SetBeginFrameSourcePaused(paused); |
| ProcessScheduledActions(); |
| } |
| |
| // BeginFrame is the mechanism that tells us that now is a good time to start |
| // making a frame. Usually this means that user input for the frame is complete. |
| // If the scheduler is busy, we queue the BeginFrame to be handled later as |
| // a BeginRetroFrame. |
| bool Scheduler::OnBeginFrameDerivedImpl(const viz::BeginFrameArgs& args) { |
| TRACE_EVENT1("cc,benchmark", "Scheduler::BeginFrame", "args", args.AsValue()); |
| |
| if (ShouldDropBeginFrame(args)) { |
| TRACE_EVENT_INSTANT0("cc", "Scheduler::BeginFrameDropped", |
| TRACE_EVENT_SCOPE_THREAD); |
| // Since we don't use the BeginFrame, we may later receive the same |
| // BeginFrame again. Thus, we can't confirm it at this point, even though we |
| // don't have any updates right now. |
| SendBeginFrameAck(args, kBeginFrameSkipped); |
| return false; |
| } |
| |
| // Trace this begin frame time through the Chrome stack |
| TRACE_EVENT_FLOW_BEGIN0( |
| TRACE_DISABLED_BY_DEFAULT("cc.debug.scheduler.frames"), |
| "viz::BeginFrameArgs", args.frame_time.since_origin().InMicroseconds()); |
| |
| if (settings_.using_synchronous_renderer_compositor) { |
| BeginImplFrameSynchronous(args); |
| return true; |
| } |
| |
| if (inside_process_scheduled_actions_) { |
| // The BFS can send a missed begin frame inside AddObserver. We can't handle |
| // a begin frame inside ProcessScheduledActions so post a task. |
| DCHECK_EQ(args.type, viz::BeginFrameArgs::MISSED); |
| DCHECK(missed_begin_frame_task_.IsCancelled()); |
| missed_begin_frame_task_.Reset(base::Bind( |
| &Scheduler::BeginImplFrameWithDeadline, base::Unretained(this), args)); |
| task_runner_->PostTask(FROM_HERE, missed_begin_frame_task_.callback()); |
| return true; |
| } |
| |
| BeginImplFrameWithDeadline(args); |
| return true; |
| } |
| |
| void Scheduler::SetVideoNeedsBeginFrames(bool video_needs_begin_frames) { |
| state_machine_.SetVideoNeedsBeginFrames(video_needs_begin_frames); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::OnDrawForLayerTreeFrameSink(bool resourceless_software_draw) { |
| DCHECK(settings_.using_synchronous_renderer_compositor); |
| DCHECK_EQ(state_machine_.begin_impl_frame_state(), |
| SchedulerStateMachine::BeginImplFrameState::IDLE); |
| DCHECK(begin_impl_frame_deadline_task_.IsCancelled()); |
| |
| state_machine_.SetResourcelessSoftwareDraw(resourceless_software_draw); |
| state_machine_.OnBeginImplFrameDeadline(); |
| ProcessScheduledActions(); |
| |
| state_machine_.OnBeginImplFrameIdle(); |
| ProcessScheduledActions(); |
| state_machine_.SetResourcelessSoftwareDraw(false); |
| } |
| |
| void Scheduler::BeginImplFrameWithDeadline(const viz::BeginFrameArgs& args) { |
| // The storage for |args| is owned by the missed begin frame task. Therefore |
| // save |args| before cancelling the task either here or in the deadline. |
| viz::BeginFrameArgs adjusted_args = args; |
| // Cancel the missed begin frame task in case the BFS sends a begin frame |
| // before the missed frame task runs. |
| missed_begin_frame_task_.Cancel(); |
| |
| base::TimeTicks now = Now(); |
| |
| // Discard missed begin frames if they are too late. In full-pipe mode, we |
| // ignore BeginFrame deadlines. |
| if (adjusted_args.type == viz::BeginFrameArgs::MISSED && |
| now > adjusted_args.deadline && |
| !settings_.wait_for_all_pipeline_stages_before_draw) { |
| skipped_last_frame_missed_exceeded_deadline_ = true; |
| SendBeginFrameAck(adjusted_args, kBeginFrameSkipped); |
| return; |
| } |
| |
| skipped_last_frame_missed_exceeded_deadline_ = false; |
| |
| // Run the previous deadline if any. |
| if (state_machine_.begin_impl_frame_state() == |
| SchedulerStateMachine::BeginImplFrameState::INSIDE_BEGIN_FRAME) { |
| OnBeginImplFrameDeadline(); |
| // We may not need begin frames any longer. |
| if (!observing_begin_frame_source_) { |
| // We need to confirm the ignored BeginFrame, since we don't have updates. |
| SendBeginFrameAck(adjusted_args, kBeginFrameSkipped); |
| return; |
| } |
| } |
| DCHECK_EQ(state_machine_.begin_impl_frame_state(), |
| SchedulerStateMachine::BeginImplFrameState::IDLE); |
| |
| bool main_thread_is_in_high_latency_mode = |
| state_machine_.main_thread_missed_last_deadline(); |
| TRACE_EVENT2("cc,benchmark", "Scheduler::BeginImplFrame", "args", |
| adjusted_args.AsValue(), "main_thread_missed_last_deadline", |
| main_thread_is_in_high_latency_mode); |
| TRACE_COUNTER1(TRACE_DISABLED_BY_DEFAULT("cc.debug.scheduler"), |
| "MainThreadLatency", main_thread_is_in_high_latency_mode); |
| |
| DCHECK_EQ(state_machine_.begin_impl_frame_state(), |
| SchedulerStateMachine::BeginImplFrameState::IDLE); |
| |
| adjusted_args.deadline -= compositor_timing_history_->DrawDurationEstimate(); |
| adjusted_args.deadline -= kDeadlineFudgeFactor; |
| |
| // TODO(khushalsagar): We need to consider the deadline fudge factor here to |
| // match the deadline used in BeginImplFrameDeadlineMode::REGULAR mode |
| // (used in the case where the impl thread needs to redraw). In the case where |
| // main_frame_to_active is fast, we should consider using |
| // BeginImplFrameDeadlineMode::LATE instead to avoid putting the main |
| // thread in high latency mode. See crbug.com/753146. |
| base::TimeDelta bmf_to_activate_threshold = |
| adjusted_args.interval - |
| compositor_timing_history_->DrawDurationEstimate() - kDeadlineFudgeFactor; |
| |
| // An estimate of time from starting the main frame on the main thread to when |
| // the resulting pending tree is activated. Note that this excludes the |
| // durations where progress is blocked due to back pressure in the pipeline |
| // (ready to commit to commit, ready to activate to activate, etc.) |
| base::TimeDelta bmf_start_to_activate = |
| compositor_timing_history_ |
| ->BeginMainFrameStartToReadyToCommitDurationEstimate() + |
| compositor_timing_history_->CommitDurationEstimate() + |
| compositor_timing_history_->CommitToReadyToActivateDurationEstimate() + |
| compositor_timing_history_->ActivateDurationEstimate(); |
| |
| base::TimeDelta bmf_to_activate_estimate_critical = |
| bmf_start_to_activate + |
| compositor_timing_history_->BeginMainFrameQueueDurationCriticalEstimate(); |
| state_machine_.SetCriticalBeginMainFrameToActivateIsFast( |
| bmf_to_activate_estimate_critical < bmf_to_activate_threshold); |
| |
| // Update the BeginMainFrame args now that we know whether the main |
| // thread will be on the critical path or not. |
| begin_main_frame_args_ = adjusted_args; |
| begin_main_frame_args_.on_critical_path = !ImplLatencyTakesPriority(); |
| |
| // If we expect the main thread to respond within this frame, defer the |
| // invalidation to merge it with the incoming main frame. Even if the response |
| // is delayed such that the raster can not be completed within this frame's |
| // draw, its better to delay the invalidation than blocking the pipeline with |
| // an extra pending tree update to be flushed. |
| base::TimeDelta time_since_main_frame_sent; |
| if (compositor_timing_history_->begin_main_frame_sent_time() != |
| base::TimeTicks()) { |
| time_since_main_frame_sent = |
| now - compositor_timing_history_->begin_main_frame_sent_time(); |
| } |
| base::TimeDelta bmf_sent_to_ready_to_commit_estimate = |
| compositor_timing_history_ |
| ->BeginMainFrameStartToReadyToCommitDurationEstimate(); |
| if (begin_main_frame_args_.on_critical_path) { |
| bmf_sent_to_ready_to_commit_estimate += |
| compositor_timing_history_ |
| ->BeginMainFrameQueueDurationCriticalEstimate(); |
| } else { |
| bmf_sent_to_ready_to_commit_estimate += |
| compositor_timing_history_ |
| ->BeginMainFrameQueueDurationNotCriticalEstimate(); |
| } |
| |
| // We defer the invalidation if we expect the main thread to respond within |
| // this frame, and our prediction in the last frame was correct. That |
| // is, if we predicted the main thread to be fast and it fails to respond |
| // before the deadline in the previous frame, we don't defer the invalidation |
| // in the next frame. |
| const bool main_thread_response_expected_before_deadline = |
| bmf_sent_to_ready_to_commit_estimate - time_since_main_frame_sent < |
| bmf_to_activate_threshold; |
| const bool previous_invalidation_maybe_skipped_for_main_frame = |
| state_machine_.should_defer_invalidation_for_fast_main_frame() && |
| state_machine_.main_thread_failed_to_respond_last_deadline(); |
| state_machine_.set_should_defer_invalidation_for_fast_main_frame( |
| main_thread_response_expected_before_deadline && |
| !previous_invalidation_maybe_skipped_for_main_frame); |
| |
| base::TimeDelta bmf_to_activate_estimate = bmf_to_activate_estimate_critical; |
| if (!begin_main_frame_args_.on_critical_path) { |
| bmf_to_activate_estimate = |
| bmf_start_to_activate + |
| compositor_timing_history_ |
| ->BeginMainFrameQueueDurationNotCriticalEstimate(); |
| } |
| bool can_activate_before_deadline = |
| CanBeginMainFrameAndActivateBeforeDeadline(adjusted_args, |
| bmf_to_activate_estimate, now); |
| |
| if (ShouldRecoverMainLatency(adjusted_args, can_activate_before_deadline)) { |
| TRACE_EVENT_INSTANT0("cc", "SkipBeginMainFrameToReduceLatency", |
| TRACE_EVENT_SCOPE_THREAD); |
| state_machine_.SetSkipNextBeginMainFrameToReduceLatency(); |
| } else if (ShouldRecoverImplLatency(adjusted_args, |
| can_activate_before_deadline)) { |
| TRACE_EVENT_INSTANT0("cc", "SkipBeginImplFrameToReduceLatency", |
| TRACE_EVENT_SCOPE_THREAD); |
| skipped_last_frame_to_reduce_latency_ = true; |
| SendBeginFrameAck(begin_main_frame_args_, kBeginFrameSkipped); |
| return; |
| } |
| |
| skipped_last_frame_to_reduce_latency_ = false; |
| |
| BeginImplFrame(adjusted_args, now); |
| } |
| |
| void Scheduler::BeginImplFrameSynchronous(const viz::BeginFrameArgs& args) { |
| TRACE_EVENT1("cc,benchmark", "Scheduler::BeginImplFrame", "args", |
| args.AsValue()); |
| // The main thread currently can't commit before we draw with the |
| // synchronous compositor, so never consider the BeginMainFrame fast. |
| state_machine_.SetCriticalBeginMainFrameToActivateIsFast(false); |
| begin_main_frame_args_ = args; |
| begin_main_frame_args_.on_critical_path = !ImplLatencyTakesPriority(); |
| |
| BeginImplFrame(args, Now()); |
| compositor_timing_history_->WillFinishImplFrame( |
| state_machine_.needs_redraw()); |
| FinishImplFrame(); |
| } |
| |
| void Scheduler::FinishImplFrame() { |
| state_machine_.OnBeginImplFrameIdle(); |
| ProcessScheduledActions(); |
| |
| DCHECK(!inside_scheduled_action_); |
| { |
| base::AutoReset<bool> mark_inside(&inside_scheduled_action_, true); |
| client_->DidFinishImplFrame(); |
| } |
| SendBeginFrameAck(begin_main_frame_args_, kBeginFrameFinished); |
| begin_impl_frame_tracker_.Finish(); |
| } |
| |
| void Scheduler::SendBeginFrameAck(const viz::BeginFrameArgs& args, |
| BeginFrameResult result) { |
| bool did_submit = false; |
| if (result == kBeginFrameFinished) |
| did_submit = state_machine_.did_submit_in_last_frame(); |
| |
| if (!did_submit) { |
| DCHECK(!inside_scheduled_action_); |
| base::AutoReset<bool> mark_inside(&inside_scheduled_action_, true); |
| client_->DidNotProduceFrame( |
| viz::BeginFrameAck(args.source_id, args.sequence_number, did_submit)); |
| } |
| |
| if (begin_frame_source_) |
| begin_frame_source_->DidFinishFrame(this); |
| } |
| |
| // BeginImplFrame starts a compositor frame that will wait up until a deadline |
| // for a BeginMainFrame+activation to complete before it times out and draws |
| // any asynchronous animation and scroll/pinch updates. |
| void Scheduler::BeginImplFrame(const viz::BeginFrameArgs& args, |
| base::TimeTicks now) { |
| DCHECK_EQ(state_machine_.begin_impl_frame_state(), |
| SchedulerStateMachine::BeginImplFrameState::IDLE); |
| DCHECK(begin_impl_frame_deadline_task_.IsCancelled()); |
| DCHECK(state_machine_.HasInitializedLayerTreeFrameSink()); |
| |
| { |
| DCHECK(!inside_scheduled_action_); |
| base::AutoReset<bool> mark_inside(&inside_scheduled_action_, true); |
| |
| begin_impl_frame_tracker_.Start(args); |
| state_machine_.OnBeginImplFrame(args.source_id, args.sequence_number); |
| devtools_instrumentation::DidBeginFrame(layer_tree_host_id_); |
| compositor_timing_history_->WillBeginImplFrame( |
| state_machine_.NewActiveTreeLikely(), args.frame_time, args.type, now); |
| client_->WillBeginImplFrame(begin_impl_frame_tracker_.Current()); |
| } |
| |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::ScheduleBeginImplFrameDeadline() { |
| // The synchronous compositor does not post a deadline task. |
| DCHECK(!settings_.using_synchronous_renderer_compositor); |
| |
| begin_impl_frame_deadline_task_.Cancel(); |
| begin_impl_frame_deadline_task_.Reset(begin_impl_frame_deadline_closure_); |
| |
| begin_impl_frame_deadline_mode_ = |
| state_machine_.CurrentBeginImplFrameDeadlineMode(); |
| switch (begin_impl_frame_deadline_mode_) { |
| case SchedulerStateMachine::BeginImplFrameDeadlineMode::NONE: |
| // No deadline. |
| return; |
| case SchedulerStateMachine::BeginImplFrameDeadlineMode::IMMEDIATE: |
| // We are ready to draw a new active tree immediately. |
| // We don't use Now() here because it's somewhat expensive to call. |
| deadline_ = base::TimeTicks(); |
| break; |
| case SchedulerStateMachine::BeginImplFrameDeadlineMode::REGULAR: |
| // We are animating on the impl thread but we can wait for some time. |
| deadline_ = begin_impl_frame_tracker_.Current().deadline; |
| break; |
| case SchedulerStateMachine::BeginImplFrameDeadlineMode::LATE: |
| // We are blocked for one reason or another and we should wait. |
| // TODO(brianderson): Handle long deadlines (that are past the next |
| // frame's frame time) properly instead of using this hack. |
| deadline_ = begin_impl_frame_tracker_.Current().frame_time + |
| begin_impl_frame_tracker_.Current().interval; |
| break; |
| case SchedulerStateMachine::BeginImplFrameDeadlineMode::BLOCKED: |
| // We are blocked because we are waiting for ReadyToDraw signal. We would |
| // post deadline after we received ReadyToDraw singal. |
| TRACE_EVENT1("cc", "Scheduler::ScheduleBeginImplFrameDeadline", |
| "deadline_mode", "blocked"); |
| return; |
| } |
| |
| TRACE_EVENT2("cc", "Scheduler::ScheduleBeginImplFrameDeadline", "mode", |
| SchedulerStateMachine::BeginImplFrameDeadlineModeToString( |
| begin_impl_frame_deadline_mode_), |
| "deadline", deadline_); |
| |
| deadline_scheduled_at_ = Now(); |
| base::TimeDelta delta = |
| std::max(deadline_ - deadline_scheduled_at_, base::TimeDelta()); |
| task_runner_->PostDelayedTask( |
| FROM_HERE, begin_impl_frame_deadline_task_.callback(), delta); |
| } |
| |
| void Scheduler::ScheduleBeginImplFrameDeadlineIfNeeded() { |
| if (settings_.using_synchronous_renderer_compositor) |
| return; |
| |
| if (state_machine_.begin_impl_frame_state() != |
| SchedulerStateMachine::BeginImplFrameState::INSIDE_BEGIN_FRAME) |
| return; |
| |
| if (begin_impl_frame_deadline_mode_ == |
| state_machine_.CurrentBeginImplFrameDeadlineMode() && |
| !begin_impl_frame_deadline_task_.IsCancelled()) { |
| return; |
| } |
| |
| ScheduleBeginImplFrameDeadline(); |
| } |
| |
| void Scheduler::OnBeginImplFrameDeadline() { |
| TRACE_EVENT0("cc,benchmark", "Scheduler::OnBeginImplFrameDeadline"); |
| begin_impl_frame_deadline_task_.Cancel(); |
| // We split the deadline actions up into two phases so the state machine |
| // has a chance to trigger actions that should occur durring and after |
| // the deadline separately. For example: |
| // * Sending the BeginMainFrame will not occur after the deadline in |
| // order to wait for more user-input before starting the next commit. |
| // * Creating a new OuputSurface will not occur during the deadline in |
| // order to allow the state machine to "settle" first. |
| compositor_timing_history_->WillFinishImplFrame( |
| state_machine_.needs_redraw()); |
| state_machine_.OnBeginImplFrameDeadline(); |
| ProcessScheduledActions(); |
| FinishImplFrame(); |
| } |
| |
| void Scheduler::DrawIfPossible() { |
| DCHECK(!inside_scheduled_action_); |
| base::AutoReset<bool> mark_inside(&inside_scheduled_action_, true); |
| bool drawing_with_new_active_tree = |
| state_machine_.active_tree_needs_first_draw() && |
| !state_machine_.previous_pending_tree_was_impl_side(); |
| compositor_timing_history_->WillDraw(); |
| state_machine_.WillDraw(); |
| DrawResult result = client_->ScheduledActionDrawIfPossible(); |
| state_machine_.DidDraw(result); |
| compositor_timing_history_->DidDraw( |
| drawing_with_new_active_tree, |
| begin_impl_frame_tracker_.DangerousMethodCurrentOrLast().frame_time, |
| client_->CompositedAnimationsCount(), |
| client_->MainThreadAnimationsCount(), |
| client_->MainThreadCompositableAnimationsCount()); |
| } |
| |
| void Scheduler::DrawForced() { |
| DCHECK(!inside_scheduled_action_); |
| base::AutoReset<bool> mark_inside(&inside_scheduled_action_, true); |
| bool drawing_with_new_active_tree = |
| state_machine_.active_tree_needs_first_draw() && |
| !state_machine_.previous_pending_tree_was_impl_side(); |
| compositor_timing_history_->WillDraw(); |
| state_machine_.WillDraw(); |
| DrawResult result = client_->ScheduledActionDrawForced(); |
| state_machine_.DidDraw(result); |
| compositor_timing_history_->DidDraw( |
| drawing_with_new_active_tree, |
| begin_impl_frame_tracker_.DangerousMethodCurrentOrLast().frame_time, |
| client_->CompositedAnimationsCount(), |
| client_->MainThreadAnimationsCount(), |
| client_->MainThreadCompositableAnimationsCount()); |
| } |
| |
| void Scheduler::SetDeferCommits(bool defer_commits) { |
| TRACE_EVENT1("cc", "Scheduler::SetDeferCommits", "defer_commits", |
| defer_commits); |
| state_machine_.SetDeferCommits(defer_commits); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::SetMainThreadWantsBeginMainFrameNotExpected(bool new_state) { |
| state_machine_.SetMainThreadWantsBeginMainFrameNotExpectedMessages(new_state); |
| ProcessScheduledActions(); |
| } |
| |
| void Scheduler::ProcessScheduledActions() { |
| // Do not perform actions during compositor shutdown. |
| if (stopped_) |
| return; |
| |
| // 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_ || inside_scheduled_action_) |
| return; |
| |
| base::AutoReset<bool> mark_inside(&inside_process_scheduled_actions_, true); |
| |
| SchedulerStateMachine::Action action; |
| do { |
| action = state_machine_.NextAction(); |
| TRACE_EVENT1(TRACE_DISABLED_BY_DEFAULT("cc.debug.scheduler"), |
| "SchedulerStateMachine", "state", AsValue()); |
| base::AutoReset<SchedulerStateMachine::Action> mark_inside_action( |
| &inside_action_, action); |
| switch (action) { |
| case SchedulerStateMachine::Action::NONE: |
| break; |
| case SchedulerStateMachine::Action::SEND_BEGIN_MAIN_FRAME: |
| compositor_timing_history_->WillBeginMainFrame( |
| begin_main_frame_args_.on_critical_path, |
| begin_main_frame_args_.frame_time); |
| state_machine_.WillSendBeginMainFrame(); |
| // TODO(brianderson): Pass begin_main_frame_args_ directly to client. |
| client_->ScheduledActionSendBeginMainFrame(begin_main_frame_args_); |
| break; |
| case SchedulerStateMachine::Action::NOTIFY_BEGIN_MAIN_FRAME_NOT_SENT: |
| state_machine_.WillNotifyBeginMainFrameNotSent(); |
| // If SendBeginMainFrameNotExpectedSoon was not previously sent by |
| // BeginImplFrameNotExpectedSoon (because the messages were not required |
| // at that time), then send it now. |
| if (!observing_begin_frame_source_) { |
| client_->SendBeginMainFrameNotExpectedSoon(); |
| } else { |
| BeginMainFrameNotExpectedUntil(begin_main_frame_args_.frame_time + |
| begin_main_frame_args_.interval); |
| } |
| break; |
| case SchedulerStateMachine::Action::COMMIT: { |
| bool commit_has_no_updates = false; |
| state_machine_.WillCommit(commit_has_no_updates); |
| compositor_timing_history_->WillCommit(); |
| client_->ScheduledActionCommit(); |
| break; |
| } |
| case SchedulerStateMachine::Action::ACTIVATE_SYNC_TREE: |
| compositor_timing_history_->WillActivate(); |
| state_machine_.WillActivate(); |
| client_->ScheduledActionActivateSyncTree(); |
| compositor_timing_history_->DidActivate(); |
| break; |
| case SchedulerStateMachine::Action::PERFORM_IMPL_SIDE_INVALIDATION: |
| state_machine_.WillPerformImplSideInvalidation(); |
| compositor_timing_history_->WillInvalidateOnImplSide(); |
| client_->ScheduledActionPerformImplSideInvalidation(); |
| break; |
| case SchedulerStateMachine::Action::DRAW_IF_POSSIBLE: |
| DrawIfPossible(); |
| break; |
| case SchedulerStateMachine::Action::DRAW_FORCED: |
| DrawForced(); |
| break; |
| case SchedulerStateMachine::Action::DRAW_ABORT: { |
| // No action is actually performed, but this allows the state machine to |
| // drain the pipeline without actually drawing. |
| state_machine_.AbortDraw(); |
| compositor_timing_history_->DrawAborted(); |
| break; |
| } |
| case SchedulerStateMachine::Action::BEGIN_LAYER_TREE_FRAME_SINK_CREATION: |
| state_machine_.WillBeginLayerTreeFrameSinkCreation(); |
| client_->ScheduledActionBeginLayerTreeFrameSinkCreation(); |
| break; |
| case SchedulerStateMachine::Action::PREPARE_TILES: |
| state_machine_.WillPrepareTiles(); |
| client_->ScheduledActionPrepareTiles(); |
| break; |
| case SchedulerStateMachine::Action::INVALIDATE_LAYER_TREE_FRAME_SINK: { |
| state_machine_.WillInvalidateLayerTreeFrameSink(); |
| client_->ScheduledActionInvalidateLayerTreeFrameSink(); |
| break; |
| } |
| } |
| } while (action != SchedulerStateMachine::Action::NONE); |
| |
| ScheduleBeginImplFrameDeadlineIfNeeded(); |
| SetupNextBeginFrameIfNeeded(); |
| } |
| |
| std::unique_ptr<base::trace_event::ConvertableToTraceFormat> |
| Scheduler::AsValue() const { |
| auto state = std::make_unique<base::trace_event::TracedValue>(); |
| AsValueInto(state.get()); |
| return std::move(state); |
| } |
| |
| void Scheduler::AsValueInto(base::trace_event::TracedValue* state) const { |
| base::TimeTicks now = Now(); |
| |
| state->BeginDictionary("state_machine"); |
| state_machine_.AsValueInto(state); |
| state->EndDictionary(); |
| |
| state->SetBoolean("observing_begin_frame_source", |
| observing_begin_frame_source_); |
| state->SetBoolean("begin_impl_frame_deadline_task", |
| !begin_impl_frame_deadline_task_.IsCancelled()); |
| state->SetBoolean("missed_begin_frame_task", |
| !missed_begin_frame_task_.IsCancelled()); |
| state->SetBoolean("skipped_last_frame_missed_exceeded_deadline", |
| skipped_last_frame_missed_exceeded_deadline_); |
| state->SetBoolean("skipped_last_frame_to_reduce_latency", |
| skipped_last_frame_to_reduce_latency_); |
| state->SetString("inside_action", |
| SchedulerStateMachine::ActionToString(inside_action_)); |
| state->SetString("begin_impl_frame_deadline_mode", |
| SchedulerStateMachine::BeginImplFrameDeadlineModeToString( |
| begin_impl_frame_deadline_mode_)); |
| |
| state->SetDouble("deadline_ms", deadline_.since_origin().InMillisecondsF()); |
| state->SetDouble("deadline_scheduled_at_ms", |
| deadline_scheduled_at_.since_origin().InMillisecondsF()); |
| |
| state->SetDouble("now_ms", Now().since_origin().InMillisecondsF()); |
| state->SetDouble("now_to_deadline_ms", (deadline_ - Now()).InMillisecondsF()); |
| state->SetDouble("now_to_deadline_scheduled_at_ms", |
| (deadline_scheduled_at_ - Now()).InMillisecondsF()); |
| |
| state->BeginDictionary("begin_impl_frame_args"); |
| begin_impl_frame_tracker_.AsValueInto(now, state); |
| state->EndDictionary(); |
| |
| state->BeginDictionary("begin_frame_observer_state"); |
| BeginFrameObserverBase::AsValueInto(state); |
| state->EndDictionary(); |
| |
| if (begin_frame_source_) { |
| state->BeginDictionary("begin_frame_source_state"); |
| begin_frame_source_->AsValueInto(state); |
| state->EndDictionary(); |
| } |
| |
| state->BeginDictionary("compositor_timing_history"); |
| compositor_timing_history_->AsValueInto(state); |
| state->EndDictionary(); |
| } |
| |
| void Scheduler::UpdateCompositorTimingHistoryRecordingEnabled() { |
| compositor_timing_history_->SetRecordingEnabled( |
| state_machine_.HasInitializedLayerTreeFrameSink() && |
| state_machine_.visible()); |
| } |
| |
| bool Scheduler::ShouldDropBeginFrame(const viz::BeginFrameArgs& args) const { |
| // Drop the BeginFrame if we don't need one. |
| if (!state_machine_.BeginFrameNeeded()) |
| return true; |
| |
| // Also ignore MISSED args in full-pipe mode, because a missed BeginFrame may |
| // have already been completed by the DisplayScheduler. In such a case, |
| // handling it now would be likely to mess up future full-pipe BeginFrames. |
| // The only situation in which we can reasonably receive MISSED args is when |
| // our frame sink hierarchy changes, since we always request BeginFrames in |
| // full-pipe mode. If surface synchronization is also enabled, we can and |
| // should use the MISSED args safely because the parent's latest |
| // CompositorFrame will block its activation until we submit a new frame. |
| if (args.type == viz::BeginFrameArgs::MISSED && |
| settings_.wait_for_all_pipeline_stages_before_draw && |
| !settings_.enable_surface_synchronization) { |
| return true; |
| } |
| |
| return false; |
| } |
| |
| bool Scheduler::ShouldRecoverMainLatency( |
| const viz::BeginFrameArgs& args, |
| bool can_activate_before_deadline) const { |
| DCHECK(!settings_.using_synchronous_renderer_compositor); |
| |
| if (!settings_.enable_latency_recovery) |
| return false; |
| |
| // The main thread is in a low latency mode and there's no need to recover. |
| if (!state_machine_.main_thread_missed_last_deadline()) |
| return false; |
| |
| // When prioritizing impl thread latency, we currently put the |
| // main thread in a high latency mode. Don't try to fight it. |
| if (state_machine_.ImplLatencyTakesPriority()) |
| return false; |
| |
| // Ensure that we have data from at least one frame before attempting latency |
| // recovery. This prevents skipping of frames during loading where the main |
| // thread is likely slow but we assume it to be fast since we have no history. |
| static const int kMinNumberOfSamplesBeforeLatencyRecovery = 1; |
| if (compositor_timing_history_ |
| ->begin_main_frame_start_to_ready_to_commit_sample_count() < |
| kMinNumberOfSamplesBeforeLatencyRecovery || |
| compositor_timing_history_->commit_to_ready_to_activate_sample_count() < |
| kMinNumberOfSamplesBeforeLatencyRecovery) { |
| return false; |
| } |
| |
| return can_activate_before_deadline; |
| } |
| |
| bool Scheduler::ShouldRecoverImplLatency( |
| const viz::BeginFrameArgs& args, |
| bool can_activate_before_deadline) const { |
| DCHECK(!settings_.using_synchronous_renderer_compositor); |
| |
| if (!settings_.enable_latency_recovery) |
| return false; |
| |
| // Disable impl thread latency recovery when using the unthrottled |
| // begin frame source since we will always get a BeginFrame before |
| // the swap ack and our heuristics below will not work. |
| if (begin_frame_source_ && !begin_frame_source_->IsThrottled()) |
| return false; |
| |
| // If we are swap throttled at the BeginFrame, that means the impl thread is |
| // very likely in a high latency mode. |
| bool impl_thread_is_likely_high_latency = state_machine_.IsDrawThrottled(); |
| if (!impl_thread_is_likely_high_latency) |
| return false; |
| |
| // The deadline may be in the past if our draw time is too long. |
| bool can_draw_before_deadline = args.frame_time < args.deadline; |
| |
| // When prioritizing impl thread latency, the deadline doesn't wait |
| // for the main thread. |
| if (state_machine_.ImplLatencyTakesPriority()) |
| return can_draw_before_deadline; |
| |
| // If we only have impl-side updates, the deadline doesn't wait for |
| // the main thread. |
| if (state_machine_.OnlyImplSideUpdatesExpected()) |
| return can_draw_before_deadline; |
| |
| // If we get here, we know the main thread is in a low-latency mode relative |
| // to the impl thread. In this case, only try to also recover impl thread |
| // latency if both the main and impl threads can run serially before the |
| // deadline. |
| return can_activate_before_deadline; |
| } |
| |
| bool Scheduler::CanBeginMainFrameAndActivateBeforeDeadline( |
| const viz::BeginFrameArgs& args, |
| base::TimeDelta bmf_to_activate_estimate, |
| base::TimeTicks now) const { |
| // Check if the main thread computation and commit can be finished before the |
| // impl thread's deadline. |
| base::TimeTicks estimated_draw_time = now + bmf_to_activate_estimate; |
| |
| return estimated_draw_time < args.deadline; |
| } |
| |
| bool Scheduler::IsBeginMainFrameSentOrStarted() const { |
| return (state_machine_.begin_main_frame_state() == |
| SchedulerStateMachine::BeginMainFrameState::SENT || |
| state_machine_.begin_main_frame_state() == |
| SchedulerStateMachine::BeginMainFrameState::STARTED); |
| } |
| |
| viz::BeginFrameAck Scheduler::CurrentBeginFrameAckForActiveTree() const { |
| return viz::BeginFrameAck(begin_main_frame_args_.source_id, |
| begin_main_frame_args_.sequence_number, true); |
| } |
| |
| void Scheduler::ClearHistoryOnNavigation() { |
| compositor_timing_history_->ClearHistoryOnNavigation(); |
| } |
| |
| } // namespace cc |