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// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "third_party/blink/renderer/platform/scheduler/main_thread/user_model.h"
#include "base/trace_event/trace_event.h"
#include "third_party/perfetto/include/perfetto/tracing/traced_value.h"
namespace blink {
namespace scheduler {
UserModel::UserModel() = default;
void UserModel::DidStartProcessingInputEvent(blink::WebInputEvent::Type type,
const base::TimeTicks now) {
last_input_signal_time_ = now;
if (type == blink::WebInputEvent::Type::kTouchStart ||
type == blink::WebInputEvent::Type::kGestureScrollBegin ||
type == blink::WebInputEvent::Type::kGesturePinchBegin) {
// Only update stats once per gesture.
if (!is_gesture_active_)
last_gesture_start_time_ = now;
is_gesture_active_ = true;
}
// We need to track continuous gestures seperatly for scroll detection
// because taps should not be confused with scrolls.
if (type == blink::WebInputEvent::Type::kGestureScrollBegin ||
type == blink::WebInputEvent::Type::kGestureScrollEnd ||
type == blink::WebInputEvent::Type::kGestureScrollUpdate ||
type == blink::WebInputEvent::Type::kGestureFlingStart ||
type == blink::WebInputEvent::Type::kGestureFlingCancel ||
type == blink::WebInputEvent::Type::kGesturePinchBegin ||
type == blink::WebInputEvent::Type::kGesturePinchEnd ||
type == blink::WebInputEvent::Type::kGesturePinchUpdate) {
last_continuous_gesture_time_ = now;
}
// If the gesture has ended, clear |is_gesture_active_| and record a UMA
// metric that tracks its duration.
if (type == blink::WebInputEvent::Type::kGestureScrollEnd ||
type == blink::WebInputEvent::Type::kGesturePinchEnd ||
type == blink::WebInputEvent::Type::kGestureFlingStart ||
type == blink::WebInputEvent::Type::kTouchEnd) {
is_gesture_active_ = false;
}
TRACE_COUNTER1(TRACE_DISABLED_BY_DEFAULT("renderer.scheduler"),
"is_gesture_active", is_gesture_active_);
pending_input_event_count_++;
}
void UserModel::DidFinishProcessingInputEvent(const base::TimeTicks now) {
last_input_signal_time_ = now;
if (pending_input_event_count_ > 0)
pending_input_event_count_--;
}
void UserModel::DidProcessDiscreteInputEvent(const base::TimeTicks now) {
last_discrete_input_time_ = now;
}
void UserModel::DidProcessDiscreteInputResponse() {
last_discrete_input_time_ = base::TimeTicks();
}
base::TimeDelta UserModel::TimeLeftInContinuousUserGesture(
base::TimeTicks now) const {
// If the input event is still pending, go into input prioritized policy and
// check again later.
if (pending_input_event_count_ > 0) {
return kGestureEstimationLimit;
}
if (last_input_signal_time_.is_null() ||
last_input_signal_time_ + kGestureEstimationLimit < now) {
return base::TimeDelta();
}
return last_input_signal_time_ + kGestureEstimationLimit - now;
}
base::TimeDelta UserModel::TimeLeftUntilDiscreteInputResponseDeadline(
base::TimeTicks now) const {
if (last_discrete_input_time_.is_null() ||
last_discrete_input_time_ + kDiscreteInputResponseDeadline < now) {
return base::TimeDelta();
}
return last_discrete_input_time_ + kDiscreteInputResponseDeadline - now;
}
bool UserModel::IsGestureExpectedSoon(
const base::TimeTicks now,
base::TimeDelta* prediction_valid_duration) {
bool was_gesture_expected = is_gesture_expected_;
is_gesture_expected_ =
IsGestureExpectedSoonImpl(now, prediction_valid_duration);
// Track when we start expecting a gesture so we can work out later if a
// gesture actually happened.
if (!was_gesture_expected && is_gesture_expected_)
last_gesture_expected_start_time_ = now;
return is_gesture_expected_;
}
bool UserModel::IsGestureExpectedSoonImpl(
const base::TimeTicks now,
base::TimeDelta* prediction_valid_duration) const {
if (is_gesture_active_) {
if (IsGestureExpectedToContinue(now, prediction_valid_duration))
return false;
*prediction_valid_duration = kExpectSubsequentGestureDeadline;
return true;
} else {
// If we have finished a gesture then a subsequent gesture is deemed likely.
if (last_continuous_gesture_time_.is_null() ||
last_continuous_gesture_time_ + kExpectSubsequentGestureDeadline <=
now) {
return false;
}
*prediction_valid_duration =
last_continuous_gesture_time_ + kExpectSubsequentGestureDeadline - now;
return true;
}
}
bool UserModel::IsGestureExpectedToContinue(
const base::TimeTicks now,
base::TimeDelta* prediction_valid_duration) const {
if (!is_gesture_active_)
return false;
base::TimeTicks expected_gesture_end_time =
last_gesture_start_time_ + kMedianGestureDuration;
if (expected_gesture_end_time > now) {
*prediction_valid_duration = expected_gesture_end_time - now;
return true;
}
return false;
}
void UserModel::Reset(base::TimeTicks now) {
last_input_signal_time_ = base::TimeTicks();
last_gesture_start_time_ = base::TimeTicks();
last_continuous_gesture_time_ = base::TimeTicks();
last_gesture_expected_start_time_ = base::TimeTicks();
last_discrete_input_time_ = base::TimeTicks();
last_reset_time_ = now;
is_gesture_active_ = false;
is_gesture_expected_ = false;
pending_input_event_count_ = 0;
}
void UserModel::WriteIntoTrace(perfetto::TracedValue context) const {
auto dict = std::move(context).WriteDictionary();
dict.Add("pending_input_event_count", pending_input_event_count_);
dict.Add("last_input_signal_time", last_input_signal_time_);
dict.Add("last_gesture_start_time", last_gesture_start_time_);
dict.Add("last_continuous_gesture_time", last_continuous_gesture_time_);
dict.Add("last_gesture_expected_start_time",
last_gesture_expected_start_time_);
dict.Add("last_reset_time", last_reset_time_);
dict.Add("is_gesture_expected", is_gesture_expected_);
dict.Add("is_gesture_active", is_gesture_active_);
}
} // namespace scheduler
} // namespace blink
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