// Copyright 2013 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.
#ifndef UI_EVENTS_LATENCY_INFO_H_
#define UI_EVENTS_LATENCY_INFO_H_
#include <utility>
#include <vector>
#include "base/basictypes.h"
#include "base/containers/small_map.h"
#include "base/time/time.h"
#include "ui/events/events_base_export.h"
namespace ui {
enum LatencyComponentType {
// ---------------------------BEGIN COMPONENT-------------------------------
// BEGIN COMPONENT is when we show the latency begin in chrome://tracing.
// Timestamp when the input event is sent from RenderWidgetHost to renderer.
INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT,
// ---------------------------NORMAL COMPONENT-------------------------------
// Timestamp when the scroll update gesture event is sent from RWH to
// renderer. In Aura, touch event's LatencyInfo is carried over to the gesture
// event. So gesture event's INPUT_EVENT_LATENCY_RWH_COMPONENT is the
// timestamp when its original touch events is sent from RWH to renderer.
// In non-aura platform, INPUT_EVENT_LATENCY_SCROLL_UPDATE_RWH_COMPONENT
// is the same as INPUT_EVENT_LATENCY_RWH_COMPONENT.
INPUT_EVENT_LATENCY_SCROLL_UPDATE_RWH_COMPONENT,
// The original timestamp of the touch event which converts to scroll update.
INPUT_EVENT_LATENCY_SCROLL_UPDATE_ORIGINAL_COMPONENT,
// Original timestamp for input event (e.g. timestamp from kernel).
INPUT_EVENT_LATENCY_ORIGINAL_COMPONENT,
// Timestamp when the UI event is created.
INPUT_EVENT_LATENCY_UI_COMPONENT,
// This is special component indicating there is rendering scheduled for
// the event associated with this LatencyInfo.
INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_COMPONENT,
// Timestamp when the touch event is acked.
INPUT_EVENT_LATENCY_ACKED_TOUCH_COMPONENT,
// Frame number when a window snapshot was requested. The snapshot
// is taken when the rendering results actually reach the screen.
WINDOW_SNAPSHOT_FRAME_NUMBER_COMPONENT,
// ---------------------------TERMINAL COMPONENT-----------------------------
// TERMINAL COMPONENT is when we show the latency end in chrome://tracing.
// Timestamp when the mouse event is acked from renderer and it does not
// cause any rendering scheduled.
INPUT_EVENT_LATENCY_TERMINATED_MOUSE_COMPONENT,
// Timestamp when the touch event is acked from renderer and it does not
// cause any rendering schedueld and does not generate any gesture event.
INPUT_EVENT_LATENCY_TERMINATED_TOUCH_COMPONENT,
// Timestamp when the gesture event is acked from renderer, and it does not
// cause any rendering schedueld.
INPUT_EVENT_LATENCY_TERMINATED_GESTURE_COMPONENT,
// Timestamp when the frame is swapped (i.e. when the rendering caused by
// input event actually takes effect).
INPUT_EVENT_LATENCY_TERMINATED_FRAME_SWAP_COMPONENT,
// This component indicates that the input causes a commit to be scheduled
// but the commit failed.
INPUT_EVENT_LATENCY_TERMINATED_COMMIT_FAILED_COMPONENT,
// This component indicates that the input causes a swap to be scheduled
// but the swap failed.
INPUT_EVENT_LATENCY_TERMINATED_SWAP_FAILED_COMPONENT,
// This component indicates that the cached LatencyInfo number exceeds the
// maximal allowed size.
LATENCY_INFO_LIST_TERMINATED_OVERFLOW_COMPONENT,
LATENCY_COMPONENT_TYPE_LAST = LATENCY_INFO_LIST_TERMINATED_OVERFLOW_COMPONENT
};
struct EVENTS_BASE_EXPORT LatencyInfo {
struct LatencyComponent {
// Nondecreasing number that can be used to determine what events happened
// in the component at the time this struct was sent on to the next
// component.
int64 sequence_number;
// Average time of events that happened in this component.
base::TimeTicks event_time;
// Count of events that happened in this component
uint32 event_count;
};
// Empirically determined constant based on a typical scroll sequence.
enum { kTypicalMaxComponentsPerLatencyInfo = 6 };
// Map a Latency Component (with a component-specific int64 id) to a
// component info.
typedef base::SmallMap<
std::map<std::pair<LatencyComponentType, int64>, LatencyComponent>,
kTypicalMaxComponentsPerLatencyInfo> LatencyMap;
LatencyInfo();
~LatencyInfo();
// Returns true if the vector |latency_info| is valid. Returns false
// if it is not valid and log the |referring_msg|.
// This function is mainly used to check the latency_info vector that
// is passed between processes using IPC message has reasonable size
// so that we are confident the IPC message is not corrupted/compromised.
// This check will go away once the IPC system has better built-in scheme
// for corruption/compromise detection.
static bool Verify(const std::vector<LatencyInfo>& latency_info,
const char* referring_msg);
// Copy LatencyComponents with type |type| from |other| into |this|.
void CopyLatencyFrom(const LatencyInfo& other, LatencyComponentType type);
// Add LatencyComponents that are in |other| but not in |this|.
void AddNewLatencyFrom(const LatencyInfo& other);
// Modifies the current sequence number for a component, and adds a new
// sequence number with the current timestamp.
void AddLatencyNumber(LatencyComponentType component,
int64 id,
int64 component_sequence_number);
// Modifies the current sequence number and adds a certain number of events
// for a specific component.
void AddLatencyNumberWithTimestamp(LatencyComponentType component,
int64 id,
int64 component_sequence_number,
base::TimeTicks time,
uint32 event_count);
// Returns true if the a component with |type| and |id| is found in
// the latency_components and the component is stored to |output| if
// |output| is not NULL. Returns false if no such component is found.
bool FindLatency(LatencyComponentType type,
int64 id,
LatencyComponent* output) const;
void RemoveLatency(LatencyComponentType type);
void Clear();
// Records the |event_type| in trace buffer as TRACE_EVENT_ASYNC_STEP.
void TraceEventType(const char* event_type);
LatencyMap latency_components;
// The unique id for matching the ASYNC_BEGIN/END trace event.
int64 trace_id;
// Whether a terminal component has been added.
bool terminated;
};
} // namespace ui
#endif // UI_EVENTS_LATENCY_INFO_H_