1 /*
2 * Copyright (C) 2020 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 // This example shows how to log trace events to the console using the console
18 // interceptor.
19
20 #include "trace_categories.h"
21
22 #include <chrono>
23 #include <thread>
24
InitializePerfetto()25 void InitializePerfetto() {
26 perfetto::TracingInitArgs args;
27 args.backends = perfetto::kInProcessBackend;
28 perfetto::Tracing::Initialize(args);
29 perfetto::TrackEvent::Register();
30 perfetto::ConsoleInterceptor::Register();
31 }
32
StartTracing()33 std::unique_ptr<perfetto::TracingSession> StartTracing() {
34 perfetto::TraceConfig cfg;
35 cfg.add_buffers()->set_size_kb(1024);
36 auto* ds_cfg = cfg.add_data_sources()->mutable_config();
37 ds_cfg->set_name("track_event");
38
39 // Enable the console interceptor.
40 ds_cfg->mutable_interceptor_config()->set_name("console");
41
42 auto tracing_session = perfetto::Tracing::NewTrace();
43 tracing_session->Setup(cfg);
44 tracing_session->StartBlocking();
45 return tracing_session;
46 }
47
DrawPlayer(int player_number)48 void DrawPlayer(int player_number) {
49 TRACE_EVENT("rendering", "DrawPlayer", "player_number", player_number);
50 // Sleep to simulate a long computation.
51 std::this_thread::sleep_for(std::chrono::milliseconds(500));
52 }
53
DrawGame()54 void DrawGame() {
55 // This is an example of an unscoped slice, which begins and ends at specific
56 // points (instead of at the end of the current block scope).
57 TRACE_EVENT_BEGIN("rendering", "DrawGame");
58 DrawPlayer(1);
59 DrawPlayer(2);
60 TRACE_EVENT_END("rendering");
61 }
62
main(int,const char **)63 int main(int, const char**) {
64 InitializePerfetto();
65 auto tracing_session = StartTracing();
66
67 // Simulate some work that emits trace events.
68 DrawGame();
69
70 tracing_session->StopBlocking();
71 return 0;
72 }
73