1 // Copyright 2013 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef UI_EVENTS_LATENCY_INFO_H_
6 #define UI_EVENTS_LATENCY_INFO_H_
11 #include "base/basictypes.h"
12 #include "base/containers/small_map.h"
13 #include "base/time/time.h"
14 #include "ui/events/events_base_export.h"
18 enum LatencyComponentType {
19 // ---------------------------BEGIN COMPONENT-------------------------------
20 // BEGIN COMPONENT is when we show the latency begin in chrome://tracing.
21 // Timestamp when the input event is sent from RenderWidgetHost to renderer.
22 INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT,
23 // ---------------------------NORMAL COMPONENT-------------------------------
24 // Timestamp when the scroll update gesture event is sent from RWH to
25 // renderer. In Aura, touch event's LatencyInfo is carried over to the gesture
26 // event. So gesture event's INPUT_EVENT_LATENCY_RWH_COMPONENT is the
27 // timestamp when its original touch events is sent from RWH to renderer.
28 // In non-aura platform, INPUT_EVENT_LATENCY_SCROLL_UPDATE_RWH_COMPONENT
29 // is the same as INPUT_EVENT_LATENCY_RWH_COMPONENT.
30 INPUT_EVENT_LATENCY_SCROLL_UPDATE_RWH_COMPONENT,
31 // The original timestamp of the touch event which converts to scroll update.
32 INPUT_EVENT_LATENCY_SCROLL_UPDATE_ORIGINAL_COMPONENT,
33 // Original timestamp for input event (e.g. timestamp from kernel).
34 INPUT_EVENT_LATENCY_ORIGINAL_COMPONENT,
35 // Timestamp when the UI event is created.
36 INPUT_EVENT_LATENCY_UI_COMPONENT,
37 // This is special component indicating there is rendering scheduled for
38 // the event associated with this LatencyInfo.
39 INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_COMPONENT,
40 // Timestamp when the touch event is acked.
41 INPUT_EVENT_LATENCY_ACKED_TOUCH_COMPONENT,
42 // Frame number when a window snapshot was requested. The snapshot
43 // is taken when the rendering results actually reach the screen.
44 WINDOW_SNAPSHOT_FRAME_NUMBER_COMPONENT,
45 // ---------------------------TERMINAL COMPONENT-----------------------------
46 // TERMINAL COMPONENT is when we show the latency end in chrome://tracing.
47 // Timestamp when the mouse event is acked from renderer and it does not
48 // cause any rendering scheduled.
49 INPUT_EVENT_LATENCY_TERMINATED_MOUSE_COMPONENT,
50 // Timestamp when the touch event is acked from renderer and it does not
51 // cause any rendering schedueld and does not generate any gesture event.
52 INPUT_EVENT_LATENCY_TERMINATED_TOUCH_COMPONENT,
53 // Timestamp when the gesture event is acked from renderer, and it does not
54 // cause any rendering schedueld.
55 INPUT_EVENT_LATENCY_TERMINATED_GESTURE_COMPONENT,
56 // Timestamp when the frame is swapped (i.e. when the rendering caused by
57 // input event actually takes effect).
58 INPUT_EVENT_LATENCY_TERMINATED_FRAME_SWAP_COMPONENT,
59 // This component indicates that the input causes a commit to be scheduled
60 // but the commit failed.
61 INPUT_EVENT_LATENCY_TERMINATED_COMMIT_FAILED_COMPONENT,
62 // This component indicates that the input causes a swap to be scheduled
63 // but the swap failed.
64 INPUT_EVENT_LATENCY_TERMINATED_SWAP_FAILED_COMPONENT,
65 // This component indicates that the cached LatencyInfo number exceeds the
66 // maximal allowed size.
67 LATENCY_INFO_LIST_TERMINATED_OVERFLOW_COMPONENT,
68 LATENCY_COMPONENT_TYPE_LAST = LATENCY_INFO_LIST_TERMINATED_OVERFLOW_COMPONENT
71 struct EVENTS_BASE_EXPORT LatencyInfo {
72 struct LatencyComponent {
73 // Nondecreasing number that can be used to determine what events happened
74 // in the component at the time this struct was sent on to the next
76 int64 sequence_number;
77 // Average time of events that happened in this component.
78 base::TimeTicks event_time;
79 // Count of events that happened in this component
83 // Empirically determined constant based on a typical scroll sequence.
84 enum { kTypicalMaxComponentsPerLatencyInfo = 6 };
86 // Map a Latency Component (with a component-specific int64 id) to a
88 typedef base::SmallMap<
89 std::map<std::pair<LatencyComponentType, int64>, LatencyComponent>,
90 kTypicalMaxComponentsPerLatencyInfo> LatencyMap;
96 // Returns true if the vector |latency_info| is valid. Returns false
97 // if it is not valid and log the |referring_msg|.
98 // This function is mainly used to check the latency_info vector that
99 // is passed between processes using IPC message has reasonable size
100 // so that we are confident the IPC message is not corrupted/compromised.
101 // This check will go away once the IPC system has better built-in scheme
102 // for corruption/compromise detection.
103 static bool Verify(const std::vector<LatencyInfo>& latency_info,
104 const char* referring_msg);
106 // Copy LatencyComponents with type |type| from |other| into |this|.
107 void CopyLatencyFrom(const LatencyInfo& other, LatencyComponentType type);
109 // Add LatencyComponents that are in |other| but not in |this|.
110 void AddNewLatencyFrom(const LatencyInfo& other);
112 // Modifies the current sequence number for a component, and adds a new
113 // sequence number with the current timestamp.
114 void AddLatencyNumber(LatencyComponentType component,
116 int64 component_sequence_number);
118 // Modifies the current sequence number and adds a certain number of events
119 // for a specific component.
120 void AddLatencyNumberWithTimestamp(LatencyComponentType component,
122 int64 component_sequence_number,
123 base::TimeTicks time,
126 // Returns true if the a component with |type| and |id| is found in
127 // the latency_components and the component is stored to |output| if
128 // |output| is not NULL. Returns false if no such component is found.
129 bool FindLatency(LatencyComponentType type,
131 LatencyComponent* output) const;
133 void RemoveLatency(LatencyComponentType type);
137 // Records the |event_type| in trace buffer as TRACE_EVENT_ASYNC_STEP.
138 void TraceEventType(const char* event_type);
140 LatencyMap latency_components;
141 // The unique id for matching the ASYNC_BEGIN/END trace event.
143 // Whether a terminal component has been added.
149 #endif // UI_EVENTS_LATENCY_INFO_H_