1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
|
// Copyright 2016 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_SCHEDULER_COMMON_THREAD_LOAD_TRACKER_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_SCHEDULER_COMMON_THREAD_LOAD_TRACKER_H_
#include "base/functional/callback.h"
#include "base/time/time.h"
#include "third_party/blink/renderer/platform/platform_export.h"
#include "third_party/blink/renderer/platform/wtf/allocator/allocator.h"
namespace blink {
namespace scheduler {
// This class tracks thread load level, i.e. percentage of wall time spent
// running tasks.
// In order to avoid bias it reports load level at regular intervals.
// Every |reporting_interval_| time units, it reports the average thread load
// level computed using a sliding window of width |reporting_interval_|.
class PLATFORM_EXPORT ThreadLoadTracker {
DISALLOW_NEW();
public:
// Callback is called with (current_time, load_level) parameters.
using Callback = base::RepeatingCallback<void(base::TimeTicks, double)>;
ThreadLoadTracker(base::TimeTicks now,
const Callback& callback,
base::TimeDelta reporting_interval);
~ThreadLoadTracker();
void Pause(base::TimeTicks now);
void Resume(base::TimeTicks now);
// Note: this does not change |thread_state_|.
void Reset(base::TimeTicks now);
void RecordTaskTime(base::TimeTicks start_time, base::TimeTicks end_time);
void RecordIdle(base::TimeTicks now);
// TODO(altimin): Count wake-ups.
private:
enum class ThreadState { kActive, kPaused };
enum class TaskState { kTaskRunning, kIdle };
// This function advances |time_| to |now|, calling |callback_|
// in the process (multiple times if needed).
void Advance(base::TimeTicks now, TaskState task_state);
double Load();
// |time_| is the last timestamp LoadTracker knows about.
base::TimeTicks time_;
base::TimeTicks next_reporting_time_;
ThreadState thread_state_;
base::TimeTicks last_state_change_time_;
base::TimeDelta reporting_interval_;
// Recorded run time in window
// [next_reporting_time - reporting_interval, next_reporting_time].
base::TimeDelta run_time_inside_window_;
Callback callback_;
};
} // namespace scheduler
} // namespace blink
#endif // THIRD_PARTY_BLINK_RENDERER_PLATFORM_SCHEDULER_COMMON_THREAD_LOAD_TRACKER_H_
|
