1 /*
2 * Copyright 2018 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include "rtc_base/experiments/cpu_speed_experiment.h"
12
13 #include <stdio.h>
14
15 #include "rtc_base/experiments/field_trial_list.h"
16 #include "rtc_base/logging.h"
17 #include "system_wrappers/include/field_trial.h"
18
19 namespace webrtc {
20 namespace {
21 constexpr char kFieldTrial[] = "WebRTC-VP8-CpuSpeed-Arm";
22 constexpr int kMinSetting = -16;
23 constexpr int kMaxSetting = -1;
24
GetValidOrEmpty(const std::vector<CpuSpeedExperiment::Config> & configs)25 std::vector<CpuSpeedExperiment::Config> GetValidOrEmpty(
26 const std::vector<CpuSpeedExperiment::Config>& configs) {
27 if (configs.empty()) {
28 return {};
29 }
30
31 for (const auto& config : configs) {
32 if (config.cpu_speed < kMinSetting || config.cpu_speed > kMaxSetting) {
33 RTC_LOG(LS_WARNING) << "Unsupported cpu speed setting, value ignored.";
34 return {};
35 }
36 }
37
38 for (size_t i = 1; i < configs.size(); ++i) {
39 if (configs[i].pixels < configs[i - 1].pixels ||
40 configs[i].cpu_speed > configs[i - 1].cpu_speed) {
41 RTC_LOG(LS_WARNING) << "Invalid parameter value provided.";
42 return {};
43 }
44 }
45
46 return configs;
47 }
48
HasLeCores(const std::vector<CpuSpeedExperiment::Config> & configs)49 bool HasLeCores(const std::vector<CpuSpeedExperiment::Config>& configs) {
50 for (const auto& config : configs) {
51 if (config.cpu_speed_le_cores == 0)
52 return false;
53 }
54 return true;
55 }
56 } // namespace
57
CpuSpeedExperiment()58 CpuSpeedExperiment::CpuSpeedExperiment() : cores_("cores") {
59 FieldTrialStructList<Config> configs(
60 {FieldTrialStructMember("pixels", [](Config* c) { return &c->pixels; }),
61 FieldTrialStructMember("cpu_speed",
62 [](Config* c) { return &c->cpu_speed; }),
63 FieldTrialStructMember(
64 "cpu_speed_le_cores",
65 [](Config* c) { return &c->cpu_speed_le_cores; })},
66 {});
67 ParseFieldTrial({&configs, &cores_}, field_trial::FindFullName(kFieldTrial));
68
69 configs_ = GetValidOrEmpty(configs.Get());
70 }
71
~CpuSpeedExperiment()72 CpuSpeedExperiment::~CpuSpeedExperiment() {}
73
GetValue(int pixels,int num_cores) const74 absl::optional<int> CpuSpeedExperiment::GetValue(int pixels,
75 int num_cores) const {
76 if (configs_.empty())
77 return absl::nullopt;
78
79 bool use_le = HasLeCores(configs_) && cores_ && num_cores <= cores_.Value();
80
81 for (const auto& config : configs_) {
82 if (pixels <= config.pixels)
83 return use_le ? absl::optional<int>(config.cpu_speed_le_cores)
84 : absl::optional<int>(config.cpu_speed);
85 }
86 return absl::optional<int>(kMinSetting);
87 }
88
89 } // namespace webrtc
90