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content / browser / tracing / background_tracing_active_scenario.cc [blame]
// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/tracing/background_tracing_active_scenario.h"
#include <set>
#include <utility>
#include "base/functional/callback_helpers.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/ref_counted_memory.h"
#include "base/metrics/histogram_macros.h"
#include "base/rand_util.h"
#include "base/strings/string_tokenizer.h"
#include "base/timer/timer.h"
#include "build/build_config.h"
#include "components/variations/hashing.h"
#include "content/browser/tracing/background_tracing_config_impl.h"
#include "content/browser/tracing/background_tracing_manager_impl.h"
#include "content/browser/tracing/background_tracing_rule.h"
#include "content/browser/tracing/tracing_controller_impl.h"
#include "content/public/browser/browser_task_traits.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/tracing_delegate.h"
#include "services/tracing/public/cpp/perfetto/perfetto_config.h"
#include "services/tracing/public/cpp/perfetto/perfetto_traced_process.h"
#include "services/tracing/public/cpp/perfetto/trace_event_data_source.h"
#include "services/tracing/public/cpp/perfetto/trace_packet_tokenizer.h"
#include "services/tracing/public/cpp/trace_startup.h"
#include "services/tracing/public/cpp/tracing_features.h"
#include "third_party/perfetto/include/perfetto/ext/tracing/core/trace_packet.h"
#include "third_party/perfetto/include/perfetto/tracing/tracing.h"
using base::trace_event::TraceConfig;
using Metrics = content::BackgroundTracingManagerImpl::Metrics;
namespace content {
class BackgroundTracingActiveScenario::TracingTimer {
public:
explicit TracingTimer(BackgroundTracingActiveScenario* scenario)
: scenario_(scenario) {
DCHECK_NE(scenario->GetConfig()->tracing_mode(),
BackgroundTracingConfigImpl::SYSTEM);
}
~TracingTimer() = default;
void StartTimer(base::TimeDelta delay) {
tracing_timer_.Start(FROM_HERE, delay, this,
&TracingTimer::TracingTimerFired);
}
void CancelTimer() { tracing_timer_.Stop(); }
void FireTimerForTesting() {
CancelTimer();
TracingTimerFired();
}
private:
void TracingTimerFired() { scenario_->BeginFinalizing(); }
raw_ptr<BackgroundTracingActiveScenario> scenario_;
base::OneShotTimer tracing_timer_;
};
class BackgroundTracingActiveScenario::TracingSession {
public:
TracingSession(BackgroundTracingActiveScenario* parent_scenario,
const TraceConfig& chrome_config,
const BackgroundTracingConfigImpl* config)
: parent_scenario_(parent_scenario) {
// TODO(khokhlov): Re-enable startup tracing in SDK build. Make sure that
// startup tracing config exactly matches non-startup tracing config.
perfetto::TraceConfig perfetto_config;
perfetto_config.mutable_incremental_state_config()->set_clear_period_ms(
config->interning_reset_interval_ms());
base::StringTokenizer data_sources(config->enabled_data_sources(), ",");
std::set<std::string> data_source_filter;
while (data_sources.GetNext()) {
data_source_filter.insert(data_sources.token());
}
perfetto_config = tracing::GetPerfettoConfigWithDataSources(
chrome_config, data_source_filter, config->requires_anonymized_data(),
/*convert_to_legacy_json=*/false,
perfetto::protos::gen::ChromeConfig::BACKGROUND);
tracing_session_ =
perfetto::Tracing::NewTrace(perfetto::BackendType::kCustomBackend);
tracing_session_->Setup(perfetto_config);
tracing_session_->SetOnStartCallback([] {
GetUIThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce(
&BackgroundTracingManagerImpl::OnStartTracingDone,
base::Unretained(&BackgroundTracingManagerImpl::GetInstance())));
});
tracing_session_->Start();
// We check IsEnabled() before creating the LegacyTracingSession,
// so any failures to start tracing at this point would be due to invalid
// configs which we treat as a failure scenario.
}
~TracingSession() {
DCHECK(!tracing_session_);
DCHECK(!TracingControllerImpl::GetInstance()->IsTracing());
}
void BeginFinalizing(base::OnceClosure on_success,
base::OnceClosure on_failure,
bool is_crash_scenario) {
// If the finalization was already in progress, ignore this call.
if (!tracing_session_) {
return;
}
if (parent_scenario_->delegate_ &&
(!parent_scenario_->delegate_->OnBackgroundTracingIdle(
parent_scenario_->GetConfig()->requires_anonymized_data()))) {
auto on_failure_cb =
base::MakeRefCounted<base::RefCountedData<base::OnceClosure>>(
std::move(on_failure));
auto tracing_session = TakeTracingSession();
tracing_session->data->SetOnStopCallback(
[tracing_session, on_failure_cb] {
GetUIThreadTaskRunner({})->PostTask(FROM_HERE,
std::move(on_failure_cb->data));
});
tracing_session->data->Stop();
return;
}
FinalizeTraceAsProtobuf(std::move(on_success));
DCHECK(!tracing_session_);
}
void AbortScenario(const base::RepeatingClosure& on_abort_callback) {
if (tracing_session_) {
auto tracing_session = TakeTracingSession();
auto on_abort_cb =
base::MakeRefCounted<base::RefCountedData<base::OnceClosure>>(
std::move(on_abort_callback));
tracing_session->data->SetOnStopCallback([on_abort_cb, tracing_session] {
GetUIThreadTaskRunner({})->PostTask(FROM_HERE,
std::move(on_abort_cb->data));
});
tracing_session->data->Stop();
} else {
on_abort_callback.Run();
}
}
private:
// Wraps the tracing session in a refcounted handle that can be passed through
// callbacks.
scoped_refptr<base::RefCountedData<std::unique_ptr<perfetto::TracingSession>>>
TakeTracingSession() {
return base::MakeRefCounted<
base::RefCountedData<std::unique_ptr<perfetto::TracingSession>>>(
std::move(tracing_session_));
}
void FinalizeTraceAsProtobuf(base::OnceClosure on_success) {
auto tracing_session = TakeTracingSession();
auto raw_data =
base::MakeRefCounted<base::RefCountedData<std::string>>(std::string());
auto parent_scenario = parent_scenario_->GetWeakPtr();
tracing_session->data->SetOnStopCallback(
[parent_scenario, tracing_session, raw_data] {
tracing_session->data->ReadTrace(
[parent_scenario, tracing_session,
raw_data](perfetto::TracingSession::ReadTraceCallbackArgs args) {
if (args.size) {
raw_data->data.append(args.data, args.size);
}
if (!args.has_more) {
GetUIThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce(
&BackgroundTracingActiveScenario::OnProtoDataComplete,
parent_scenario, std::move(raw_data->data)));
}
});
});
tracing_session->data->Stop();
if (on_success) {
std::move(on_success).Run();
}
}
const raw_ptr<BackgroundTracingActiveScenario> parent_scenario_;
std::unique_ptr<perfetto::TracingSession> tracing_session_;
};
BackgroundTracingActiveScenario::BackgroundTracingActiveScenario(
std::unique_ptr<BackgroundTracingConfigImpl> config,
TracingDelegate* delegate,
base::OnceClosure on_aborted_callback)
: config_(std::move(config)),
delegate_(delegate),
on_aborted_callback_(std::move(on_aborted_callback)) {
DCHECK(config_ && !config_->rules().empty());
for (const auto& rule : config_->rules()) {
rule->Install(
base::BindRepeating(&BackgroundTracingActiveScenario::OnRuleTriggered,
base::Unretained(this)));
}
}
BackgroundTracingActiveScenario::~BackgroundTracingActiveScenario() {
for (const auto& rule : config_->rules()) {
rule->Uninstall();
}
}
const BackgroundTracingConfigImpl* BackgroundTracingActiveScenario::GetConfig()
const {
return config_.get();
}
void BackgroundTracingActiveScenario::SetState(State new_state) {
auto old_state = scenario_state_;
scenario_state_ = new_state;
if ((old_state == State::kTracing) &&
base::trace_event::TraceLog::GetInstance()->IsEnabled()) {
// Leaving the kTracing state means we're supposed to have fully
// shut down tracing at this point. Since StartTracing directly enables
// tracing in TraceLog, in addition to going through Mojo, there's an
// edge-case where tracing is rapidly stopped after starting, too quickly
// for the TraceEventAgent of the browser process to register itself,
// which means that we're left in a state where the Mojo interface doesn't
// think we're tracing but TraceLog is still enabled. If that's the case,
// we abort tracing here.
DCHECK_NE(config_->tracing_mode(), BackgroundTracingConfigImpl::SYSTEM);
base::trace_event::TraceLog::GetInstance()->SetDisabled(
base::trace_event::TraceLog::RECORDING_MODE);
}
if (scenario_state_ == State::kAborted) {
DCHECK_NE(config_->tracing_mode(), BackgroundTracingConfigImpl::SYSTEM);
tracing_session_.reset();
tracing_timer_.reset();
std::move(on_aborted_callback_).Run();
}
}
void BackgroundTracingActiveScenario::FireTimerForTesting() {
DCHECK(tracing_timer_);
tracing_timer_->FireTimerForTesting();
}
void BackgroundTracingActiveScenario::SetRuleTriggeredCallbackForTesting(
const base::RepeatingClosure& callback) {
rule_triggered_callback_for_testing_ = callback;
}
base::WeakPtr<BackgroundTracingActiveScenario>
BackgroundTracingActiveScenario::GetWeakPtr() {
return weak_ptr_factory_.GetWeakPtr();
}
void BackgroundTracingActiveScenario::StartTracingIfConfigNeedsIt() {
DCHECK(config_);
if (config_->tracing_mode() == BackgroundTracingConfigImpl::PREEMPTIVE) {
StartTracing();
}
// There is nothing to do in case of reactive tracing.
}
bool BackgroundTracingActiveScenario::StartTracing() {
DCHECK_NE(config_->tracing_mode(), BackgroundTracingConfigImpl::SYSTEM);
TraceConfig chrome_config = config_->GetTraceConfig();
// Activate the categories immediately. StartTracing eventually does this
// itself, but asynchronously via Mojo, and in the meantime events will be
// dropped. This ensures that we start recording events for those categories
// immediately.
DCHECK(!tracing_session_);
tracing_session_ =
std::make_unique<TracingSession>(this, chrome_config, config_.get());
SetState(State::kTracing);
BackgroundTracingManagerImpl::RecordMetric(Metrics::RECORDING_ENABLED);
return true;
}
void BackgroundTracingActiveScenario::BeginFinalizing() {
DCHECK_NE(config_->tracing_mode(), BackgroundTracingConfigImpl::SYSTEM);
tracing_timer_.reset();
base::OnceClosure on_begin_finalization_success = base::BindOnce(
[](base::WeakPtr<BackgroundTracingActiveScenario> weak_this) {
if (!weak_this) {
return;
}
weak_this->SetState(State::kFinalizing);
BackgroundTracingManagerImpl::RecordMetric(
Metrics::FINALIZATION_ALLOWED);
},
weak_ptr_factory_.GetWeakPtr());
base::OnceClosure on_begin_finalization_failure = base::BindOnce(
[](base::WeakPtr<BackgroundTracingActiveScenario> weak_this) {
if (!weak_this) {
return;
}
BackgroundTracingManagerImpl::RecordMetric(
Metrics::FINALIZATION_DISALLOWED);
weak_this->SetState(State::kAborted);
},
weak_ptr_factory_.GetWeakPtr());
tracing_session_->BeginFinalizing(std::move(on_begin_finalization_success),
std::move(on_begin_finalization_failure),
last_triggered_rule_->is_crash());
}
void BackgroundTracingActiveScenario::OnProtoDataComplete(
std::string&& serialized_trace) {
BackgroundTracingManagerImpl::GetInstance().OnProtoDataComplete(
std::move(serialized_trace), config_->scenario_name(),
last_triggered_rule_->rule_id(), config_->requires_anonymized_data(),
last_triggered_rule_->is_crash(), base::Token::CreateRandom());
tracing_session_.reset();
SetState(State::kIdle);
// Now that a trace has completed, we may need to enable recording again.
StartTracingIfConfigNeedsIt();
}
void BackgroundTracingActiveScenario::AbortScenario() {
for (const auto& rule : config_->rules()) {
rule->Uninstall();
}
if (tracing_session_) {
tracing_session_->AbortScenario(base::BindRepeating(
[](base::WeakPtr<BackgroundTracingActiveScenario> weak_this) {
if (weak_this) {
weak_this->SetState(State::kAborted);
}
},
weak_ptr_factory_.GetWeakPtr()));
} else if (config_->tracing_mode() == BackgroundTracingConfig::SYSTEM) {
// We can't 'abort' system tracing since we aren't the consumer. Instead we
// send a trigger into the system tracing so that we can tell the time the
// scenario stopped.
perfetto::Tracing::ActivateTriggers(
{"org.chromium.background_tracing.scenario_aborted"}, /*ttl_ms=*/0);
} else {
// Setting the kAborted state will cause |this| to be destroyed.
SetState(State::kAborted);
}
}
bool BackgroundTracingActiveScenario::OnRuleTriggered(
const BackgroundTracingRule* triggered_rule) {
DCHECK_NE(state(), State::kAborted);
last_triggered_rule_ = triggered_rule;
base::TimeDelta trace_delay = triggered_rule->GetTraceDelay();
switch (config_->tracing_mode()) {
case BackgroundTracingConfigImpl::REACTIVE:
// In reactive mode, a trigger starts tracing, or finalizes tracing
// immediately if it's already running.
BackgroundTracingManagerImpl::RecordMetric(Metrics::REACTIVE_TRIGGERED);
if (state() != State::kTracing) {
// It was not already tracing, start a new trace.
if (!StartTracing()) {
return false;
}
} else {
return false;
}
break;
case BackgroundTracingConfigImpl::SYSTEM:
BackgroundTracingManagerImpl::RecordMetric(Metrics::SYSTEM_TRIGGERED);
perfetto::Tracing::ActivateTriggers({triggered_rule->rule_id()},
/*ttl_ms=*/0);
if (!rule_triggered_callback_for_testing_.is_null()) {
rule_triggered_callback_for_testing_.Run();
}
return true;
case BackgroundTracingConfigImpl::PREEMPTIVE:
// In preemptive mode, a trigger starts finalizing a trace if one is
// running and we haven't got a finalization timer running,
// otherwise we do nothing.
if ((state() != State::kTracing) || tracing_timer_) {
return false;
}
BackgroundTracingManagerImpl::RecordMetric(Metrics::PREEMPTIVE_TRIGGERED);
break;
}
if (trace_delay.is_zero()) {
BeginFinalizing();
} else {
tracing_timer_ = std::make_unique<TracingTimer>(this);
tracing_timer_->StartTimer(trace_delay);
}
if (!rule_triggered_callback_for_testing_.is_null()) {
rule_triggered_callback_for_testing_.Run();
}
return true;
}
void BackgroundTracingActiveScenario::GenerateMetadataProto(
perfetto::protos::pbzero::ChromeMetadataPacket* metadata) {
if (!last_triggered_rule_) {
return;
}
auto* background_tracing_metadata =
metadata->set_background_tracing_metadata();
uint32_t scenario_name_hash = variations::HashName(config_->scenario_name());
background_tracing_metadata->set_scenario_name_hash(scenario_name_hash);
auto* triggered_rule = background_tracing_metadata->set_triggered_rule();
last_triggered_rule_->GenerateMetadataProto(triggered_rule);
}
} // namespace content