xref: /aosp_15_r20/external/perfetto/src/tracing/service/metatrace_writer.cc (revision 6dbdd20afdafa5e3ca9b8809fa73465d530080dc)
1 /*
2  * Copyright (C) 2019 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 #include "src/tracing/service/metatrace_writer.h"
18 
19 #include "perfetto/base/logging.h"
20 #include "perfetto/base/task_runner.h"
21 #include "perfetto/ext/tracing/core/trace_writer.h"
22 #include "perfetto/tracing/core/data_source_descriptor.h"
23 
24 #include "protos/perfetto/trace/perfetto/perfetto_metatrace.pbzero.h"
25 #include "protos/perfetto/trace/trace_packet.pbzero.h"
26 
27 namespace perfetto {
28 
MetatraceWriter()29 MetatraceWriter::MetatraceWriter() : weak_ptr_factory_(this) {}
30 
~MetatraceWriter()31 MetatraceWriter::~MetatraceWriter() {
32   Disable();
33 }
34 
Enable(base::TaskRunner * task_runner,std::unique_ptr<TraceWriter> trace_writer,uint32_t tags)35 void MetatraceWriter::Enable(base::TaskRunner* task_runner,
36                              std::unique_ptr<TraceWriter> trace_writer,
37                              uint32_t tags) {
38   PERFETTO_DCHECK_THREAD(thread_checker_);
39   if (started_) {
40     PERFETTO_DFATAL_OR_ELOG("Metatrace already started from this instance");
41     return;
42   }
43   task_runner_ = task_runner;
44   trace_writer_ = std::move(trace_writer);
45   auto weak_ptr = weak_ptr_factory_.GetWeakPtr();
46   bool enabled = metatrace::Enable(
47       [weak_ptr] {
48         if (weak_ptr)
49           weak_ptr->WriteAllAvailableEvents();
50       },
51       task_runner, tags);
52   if (!enabled)
53     return;
54   started_ = true;
55 }
56 
Disable()57 void MetatraceWriter::Disable() {
58   PERFETTO_DCHECK_THREAD(thread_checker_);
59   if (!started_)
60     return;
61   metatrace::Disable();
62   started_ = false;
63   trace_writer_.reset();
64 }
65 
WriteAllAvailableEvents()66 void MetatraceWriter::WriteAllAvailableEvents() {
67   PERFETTO_DCHECK_THREAD(thread_checker_);
68   if (!started_)
69     return;
70   for (auto it = metatrace::RingBuffer::GetReadIterator(); it; ++it) {
71     auto type_and_id = it->type_and_id.load(std::memory_order_acquire);
72     if (type_and_id == 0)
73       break;  // Stop at the first incomplete event.
74 
75     auto packet = trace_writer_->NewTracePacket();
76     packet->set_timestamp(it->timestamp_ns());
77     auto* evt = packet->set_perfetto_metatrace();
78     uint16_t type = type_and_id & metatrace::Record::kTypeMask;
79     uint16_t id = type_and_id & ~metatrace::Record::kTypeMask;
80     if (type == metatrace::Record::kTypeCounter) {
81       evt->set_counter_id(id);
82       evt->set_counter_value(it->counter_value);
83     } else {
84       evt->set_event_id(id);
85       evt->set_event_duration_ns(it->duration_ns);
86     }
87 
88     evt->set_thread_id(static_cast<uint32_t>(it->thread_id));
89 
90     if (metatrace::RingBuffer::has_overruns())
91       evt->set_has_overruns(true);
92   }
93   // The |it| destructor will automatically update the read index position in
94   // the meta-trace ring buffer.
95 }
96 
WriteAllAndFlushTraceWriter(std::function<void ()> callback)97 void MetatraceWriter::WriteAllAndFlushTraceWriter(
98     std::function<void()> callback) {
99   PERFETTO_DCHECK_THREAD(thread_checker_);
100   if (!started_)
101     return;
102   WriteAllAvailableEvents();
103   trace_writer_->Flush(std::move(callback));
104 }
105 
106 }  // namespace perfetto
107