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// Copyright 2014 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 "content/browser/renderer_host/input/render_widget_host_latency_tracker.h"
#include <stddef.h>
#include "base/logging.h"
#include "base/metrics/histogram_functions.h"
#include "base/metrics/histogram_macros.h"
#include "build/build_config.h"
#include "components/rappor/public/rappor_utils.h"
#include "content/browser/renderer_host/render_widget_host_delegate.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/common/content_client.h"
#include "ui/events/blink/web_input_event_traits.h"
#include "ui/latency/latency_histogram_macros.h"
using blink::WebGestureEvent;
using blink::WebInputEvent;
using blink::WebMouseEvent;
using blink::WebMouseWheelEvent;
using blink::WebTouchEvent;
using ui::LatencyInfo;
namespace content {
RenderWidgetHostLatencyTracker::RenderWidgetHostLatencyTracker(
RenderWidgetHostDelegate* delegate)
: has_seen_first_gesture_scroll_update_(false),
active_multi_finger_gesture_(false),
touch_start_default_prevented_(false),
render_widget_host_delegate_(delegate) {}
RenderWidgetHostLatencyTracker::~RenderWidgetHostLatencyTracker() {}
void RenderWidgetHostLatencyTracker::ComputeInputLatencyHistograms(
WebInputEvent::Type type,
const LatencyInfo& latency,
InputEventAckState ack_result) {
// If this event was coalesced into another event, ignore it, as the event it
// was coalesced into will reflect the full latency.
if (latency.coalesced())
return;
if (latency.source_event_type() == ui::SourceEventType::UNKNOWN ||
latency.source_event_type() == ui::SourceEventType::OTHER) {
return;
}
// The event will have gone through OnInputEvent(). So the BEGIN_RWH component
// should always be available here.
base::TimeTicks rwh_timestamp;
bool found_component = latency.FindLatency(
ui::INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT, &rwh_timestamp);
DCHECK(found_component);
bool multi_finger_touch_gesture =
WebInputEvent::IsTouchEventType(type) && active_multi_finger_gesture_;
bool action_prevented = ack_result == INPUT_EVENT_ACK_STATE_CONSUMED;
// Touchscreen tap and scroll gestures depend on the disposition of the touch
// start and the current touch. For touch start,
// touch_start_default_prevented_ == (ack_result ==
// INPUT_EVENT_ACK_STATE_CONSUMED).
if (WebInputEvent::IsTouchEventType(type))
action_prevented |= touch_start_default_prevented_;
std::string event_name = WebInputEvent::GetName(type);
if (latency.source_event_type() == ui::KEY_PRESS)
event_name = "KeyPress";
std::string default_action_status =
action_prevented ? "DefaultPrevented" : "DefaultAllowed";
base::TimeTicks main_thread_timestamp;
if (latency.FindLatency(ui::INPUT_EVENT_LATENCY_RENDERER_MAIN_COMPONENT,
&main_thread_timestamp)) {
if (!multi_finger_touch_gesture) {
UMA_HISTOGRAM_INPUT_LATENCY_MILLISECONDS(
"Event.Latency.QueueingTime." + event_name + default_action_status,
rwh_timestamp, main_thread_timestamp);
}
}
base::TimeTicks rwh_ack_timestamp;
if (latency.FindLatency(ui::INPUT_EVENT_LATENCY_ACK_RWH_COMPONENT,
&rwh_ack_timestamp)) {
if (!multi_finger_touch_gesture && !main_thread_timestamp.is_null()) {
UMA_HISTOGRAM_INPUT_LATENCY_MILLISECONDS(
"Event.Latency.BlockingTime." + event_name + default_action_status,
main_thread_timestamp, rwh_ack_timestamp);
}
}
}
void RenderWidgetHostLatencyTracker::OnInputEvent(
const blink::WebInputEvent& event,
LatencyInfo* latency) {
DCHECK(latency);
DCHECK_CURRENTLY_ON(BrowserThread::UI);
OnEventStart(latency);
if (event.GetType() == WebInputEvent::kTouchStart) {
const WebTouchEvent& touch_event =
*static_cast<const WebTouchEvent*>(&event);
DCHECK(touch_event.touches_length >= 1);
active_multi_finger_gesture_ = touch_event.touches_length != 1;
}
if (latency->source_event_type() == ui::KEY_PRESS) {
DCHECK(event.GetType() == WebInputEvent::kChar ||
event.GetType() == WebInputEvent::kRawKeyDown);
}
// This is the only place to add the BEGIN_RWH component. So this component
// should not already be present in the latency info.
bool found_component = latency->FindLatency(
ui::INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT, nullptr);
DCHECK(!found_component);
if (!event.TimeStamp().is_null() &&
!latency->FindLatency(ui::INPUT_EVENT_LATENCY_ORIGINAL_COMPONENT,
nullptr)) {
base::TimeTicks timestamp_now = base::TimeTicks::Now();
base::TimeTicks timestamp_original = event.TimeStamp();
// Timestamp from platform input can wrap, e.g. 32 bits timestamp
// for Xserver and Window MSG time will wrap about 49.6 days. Do a
// sanity check here and if wrap does happen, use TimeTicks::Now()
// as the timestamp instead.
if ((timestamp_now - timestamp_original).InDays() > 0)
timestamp_original = timestamp_now;
latency->AddLatencyNumberWithTimestamp(
ui::INPUT_EVENT_LATENCY_ORIGINAL_COMPONENT,
timestamp_original,
1);
}
latency->AddLatencyNumberWithTraceName(
ui::INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT,
WebInputEvent::GetName(event.GetType()));
if (event.GetType() == blink::WebInputEvent::kGestureScrollBegin) {
has_seen_first_gesture_scroll_update_ = false;
} else if (event.GetType() == blink::WebInputEvent::kGestureScrollUpdate) {
// Make a copy of the INPUT_EVENT_LATENCY_ORIGINAL_COMPONENT with a
// different name INPUT_EVENT_LATENCY_SCROLL_UPDATE_ORIGINAL_COMPONENT.
// So we can track the latency specifically for scroll update events.
base::TimeTicks original_event_timestamp;
if (latency->FindLatency(ui::INPUT_EVENT_LATENCY_ORIGINAL_COMPONENT,
&original_event_timestamp)) {
latency->AddLatencyNumberWithTimestamp(
has_seen_first_gesture_scroll_update_
? ui::INPUT_EVENT_LATENCY_SCROLL_UPDATE_ORIGINAL_COMPONENT
: ui::INPUT_EVENT_LATENCY_FIRST_SCROLL_UPDATE_ORIGINAL_COMPONENT,
original_event_timestamp, 1);
}
has_seen_first_gesture_scroll_update_ = true;
}
}
void RenderWidgetHostLatencyTracker::OnInputEventAck(
const blink::WebInputEvent& event,
LatencyInfo* latency, InputEventAckState ack_result) {
DCHECK(latency);
// Latency ends if an event is acked but does not cause render scheduling.
bool rendering_scheduled = latency->FindLatency(
ui::INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_MAIN_COMPONENT, nullptr);
rendering_scheduled |= latency->FindLatency(
ui::INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_IMPL_COMPONENT, nullptr);
if (WebInputEvent::IsTouchEventType(event.GetType())) {
const WebTouchEvent& touch_event =
*static_cast<const WebTouchEvent*>(&event);
if (event.GetType() == WebInputEvent::kTouchStart) {
touch_start_default_prevented_ =
ack_result == INPUT_EVENT_ACK_STATE_CONSUMED;
} else if (event.GetType() == WebInputEvent::kTouchEnd ||
event.GetType() == WebInputEvent::kTouchCancel) {
active_multi_finger_gesture_ = touch_event.touches_length > 2;
}
}
latency->AddLatencyNumber(ui::INPUT_EVENT_LATENCY_ACK_RWH_COMPONENT);
// If this event couldn't have caused a gesture event, and it didn't trigger
// rendering, we're done processing it. If the event got coalesced then
// terminate it as well. We also exclude cases where we're against the scroll
// extent from scrolling metrics.
if (!rendering_scheduled || latency->coalesced() ||
(event.GetType() == WebInputEvent::kGestureScrollUpdate &&
ack_result == INPUT_EVENT_ACK_STATE_NO_CONSUMER_EXISTS)) {
latency->Terminate();
}
ComputeInputLatencyHistograms(event.GetType(), *latency, ack_result);
}
void RenderWidgetHostLatencyTracker::OnEventStart(ui::LatencyInfo* latency) {
static uint64_t global_trace_id = 0;
latency->set_trace_id(++global_trace_id);
latency->set_ukm_source_id(
render_widget_host_delegate_->GetUkmSourceIdForLastCommittedSource());
}
} // namespace content
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