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
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
content / browser / devtools / protocol / tracing_handler.cc [blame]
// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/342213636): Remove this and spanify to fix the errors.
#pragma allow_unsafe_buffers
#endif
#include "content/browser/devtools/protocol/tracing_handler.h"
#include <algorithm>
#include <cmath>
#include <memory>
#include <optional>
#include <set>
#include <string>
#include <utility>
#include <vector>
#include "base/format_macros.h"
#include "base/functional/bind.h"
#include "base/json/json_writer.h"
#include "base/memory/ref_counted_memory.h"
#include "base/numerics/safe_conversions.h"
#include "base/strings/strcat.h"
#include "base/strings/string_split.h"
#include "base/strings/stringprintf.h"
#include "base/time/time.h"
#include "base/timer/timer.h"
#include "base/trace_event/memory_dump_manager.h"
#include "base/trace_event/trace_event_impl.h"
#include "base/trace_event/traced_value.h"
#include "base/trace_event/tracing_agent.h"
#include "base/values.h"
#include "build/build_config.h"
#include "content/browser/devtools/devtools_agent_host_impl.h"
#include "content/browser/devtools/devtools_io_context.h"
#include "content/browser/devtools/devtools_stream_file.h"
#include "content/browser/devtools/devtools_traceable_screenshot.h"
#include "content/browser/devtools/devtools_video_consumer.h"
#include "content/browser/devtools/tracing_process_set_monitor.h"
#include "content/browser/gpu/gpu_process_host.h"
#include "content/browser/renderer_host/frame_tree.h"
#include "content/browser/renderer_host/frame_tree_node.h"
#include "content/browser/renderer_host/navigation_request.h"
#include "content/browser/renderer_host/render_frame_host_impl.h"
#include "content/browser/renderer_host/render_widget_host_impl.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_service.h"
#include "content/public/browser/web_contents.h"
#include "services/resource_coordinator/public/cpp/memory_instrumentation/memory_instrumentation.h"
#include "services/tracing/public/cpp/perfetto/perfetto_config.h"
#include "services/tracing/public/cpp/perfetto/perfetto_session.h"
#include "services/tracing/public/cpp/perfetto/trace_packet_tokenizer.h"
#include "services/tracing/public/cpp/trace_startup_config.h"
#include "services/tracing/public/cpp/tracing_features.h"
#include "services/tracing/public/mojom/constants.mojom-forward.h"
#include "third_party/abseil-cpp/absl/strings/ascii.h"
#include "third_party/inspector_protocol/crdtp/json.h"
#if BUILDFLAG(IS_ANDROID)
#include "content/browser/renderer_host/compositor_impl_android.h"
#endif
namespace content::protocol {
namespace {
const double kMinimumReportingInterval = 250.0;
const char kRecordModeParam[] = "record_mode";
const char kTraceBufferSizeInKb[] = "trace_buffer_size_in_kb";
const char kTrackEventDataSourceName[] = "track_event";
// Frames need to be at least 1x1, otherwise nothing would be captured.
constexpr gfx::Size kMinFrameSize = gfx::Size(1, 1);
// Frames do not need to be greater than 500x500 for tracing.
constexpr gfx::Size kMaxFrameSize = gfx::Size(500, 500);
// Convert from camel case to separator + lowercase.
std::string ConvertFromCamelCase(const std::string& in_str, char separator) {
std::string out_str;
out_str.reserve(in_str.size());
for (char c : in_str) {
if (absl::ascii_isupper(static_cast<unsigned char>(c))) {
out_str.push_back(separator);
out_str.push_back(absl::ascii_tolower(static_cast<unsigned char>(c)));
} else {
out_str.push_back(c);
}
}
return out_str;
}
base::Value ConvertDictKeyStyle(const base::Value& value) {
const base::Value::Dict* dict = value.GetIfDict();
if (dict) {
base::Value::Dict out;
for (auto kv : *dict) {
out.Set(ConvertFromCamelCase(kv.first, '_'),
ConvertDictKeyStyle(kv.second));
}
return base::Value(std::move(out));
}
const base::Value::List* list = value.GetIfList();
if (list) {
base::Value::List out;
for (const auto& v : *list) {
out.Append(ConvertDictKeyStyle(v));
}
return base::Value(std::move(out));
}
return value.Clone();
}
class DevToolsTraceEndpointProxy : public TracingController::TraceDataEndpoint {
public:
explicit DevToolsTraceEndpointProxy(base::WeakPtr<TracingHandler> handler)
: tracing_handler_(handler) {}
void ReceiveTraceChunk(std::unique_ptr<std::string> chunk) override {
if (TracingHandler* h = tracing_handler_.get())
h->OnTraceDataCollected(std::move(chunk));
}
void ReceivedTraceFinalContents() override {
if (TracingHandler* h = tracing_handler_.get())
h->OnTraceComplete();
}
private:
~DevToolsTraceEndpointProxy() override = default;
base::WeakPtr<TracingHandler> tracing_handler_;
};
class DevToolsStreamEndpoint : public TracingController::TraceDataEndpoint {
public:
explicit DevToolsStreamEndpoint(
base::WeakPtr<TracingHandler> handler,
const scoped_refptr<DevToolsStreamFile>& stream)
: stream_(stream), tracing_handler_(handler) {}
// CompressedStringEndpoint calls these methods on a background thread.
void ReceiveTraceChunk(std::unique_ptr<std::string> chunk) override {
if (!BrowserThread::CurrentlyOn(BrowserThread::UI)) {
GetUIThreadTaskRunner({})->PostTask(
FROM_HERE, base::BindOnce(&DevToolsStreamEndpoint::ReceiveTraceChunk,
this, std::move(chunk)));
return;
}
stream_->Append(std::move(chunk));
}
void ReceivedTraceFinalContents() override {
if (!BrowserThread::CurrentlyOn(BrowserThread::UI)) {
GetUIThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce(&DevToolsStreamEndpoint::ReceivedTraceFinalContents,
this));
return;
}
if (TracingHandler* h = tracing_handler_.get())
h->OnTraceToStreamComplete(stream_->handle());
}
private:
~DevToolsStreamEndpoint() override = default;
scoped_refptr<DevToolsStreamFile> stream_;
base::WeakPtr<TracingHandler> tracing_handler_;
};
std::string GetProcessHostHex(RenderProcessHost* host) {
return base::StringPrintf("0x%" PRIxPTR, reinterpret_cast<uintptr_t>(host));
}
void SendProcessReadyInBrowserEvent(const base::UnguessableToken& frame_token,
RenderProcessHost* host) {
auto data = std::make_unique<base::trace_event::TracedValue>();
data->SetString("frame", frame_token.ToString());
data->SetString("processPseudoId", GetProcessHostHex(host));
data->SetInteger("processId", static_cast<int>(host->GetProcess().Pid()));
TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"),
"ProcessReadyInBrowser", TRACE_EVENT_SCOPE_THREAD,
"data", std::move(data));
}
void FillFrameData(base::trace_event::TracedValue* data,
RenderFrameHostImpl* frame_host,
const GURL& url) {
CHECK(frame_host);
GURL::Replacements strip_fragment;
strip_fragment.ClearRef();
std::string trimmed_url = url.ReplaceComponents(strip_fragment).spec();
data->SetString("frame", frame_host->devtools_frame_token().ToString());
data->SetString("url", std::move(trimmed_url));
data->SetString("name", frame_host->GetFrameName());
data->SetBoolean("isOutermostMainFrame", frame_host->IsOutermostMainFrame());
// Use FrameTree's primary status since the `frame_host` itself might not be
// the primary main RenderFrameHost yet, if this function is called when
// `frame_host` is still speculative / pending commit.
data->SetBoolean("isInPrimaryMainFrame",
frame_host->IsOutermostMainFrame() &&
frame_host->frame_tree()->is_primary());
if (frame_host->GetParent()) {
data->SetString(
"parent", frame_host->GetParent()->GetDevToolsFrameToken().ToString());
}
RenderProcessHost* process_host = frame_host->GetProcess();
const base::Process& process_handle = process_host->GetProcess();
if (!process_handle.IsValid()) {
data->SetString("processPseudoId", GetProcessHostHex(process_host));
frame_host->GetProcess()->PostTaskWhenProcessIsReady(
base::BindOnce(&SendProcessReadyInBrowserEvent,
frame_host->devtools_frame_token(), process_host));
} else {
// Cast process id to int to be compatible with tracing.
data->SetInteger("processId", static_cast<int>(process_handle.Pid()));
}
}
std::optional<base::trace_event::MemoryDumpLevelOfDetail>
StringToMemoryDumpLevelOfDetail(const std::string& str) {
if (str == Tracing::MemoryDumpLevelOfDetailEnum::Detailed)
return {base::trace_event::MemoryDumpLevelOfDetail::kDetailed};
if (str == Tracing::MemoryDumpLevelOfDetailEnum::Background)
return {base::trace_event::MemoryDumpLevelOfDetail::kBackground};
if (str == Tracing::MemoryDumpLevelOfDetailEnum::Light)
return {base::trace_event::MemoryDumpLevelOfDetail::kLight};
return {};
}
void AddPidsToProcessFilter(
const std::unordered_set<base::ProcessId>& included_process_ids,
perfetto::TraceConfig& trace_config) {
const std::string kDataSourceName = kTrackEventDataSourceName;
for (auto& data_source : *(trace_config.mutable_data_sources())) {
auto* source_config = data_source.mutable_config();
if (source_config->name() == kDataSourceName) {
for (auto& enabled_pid : included_process_ids) {
*data_source.add_producer_name_filter() = base::StrCat(
{tracing::mojom::kPerfettoProducerNamePrefix,
base::NumberToString(static_cast<uint32_t>(enabled_pid))});
}
break;
}
}
}
bool IsChromeDataSource(const std::string& data_source_name) {
return base::StartsWith(data_source_name, "org.chromium.") ||
data_source_name == "track_event";
}
std::optional<perfetto::BackendType> GetBackendTypeFromParameters(
const std::string& tracing_backend,
perfetto::TraceConfig& perfetto_config) {
if (tracing_backend == Tracing::TracingBackendEnum::Chrome)
return perfetto::BackendType::kCustomBackend;
if (tracing_backend == Tracing::TracingBackendEnum::System)
return perfetto::BackendType::kSystemBackend;
if (tracing_backend == Tracing::TracingBackendEnum::Auto) {
// Use the Chrome backend by default, unless there are non-Chrome data
// sources specified in the config.
for (auto& data_source : *(perfetto_config.mutable_data_sources())) {
auto* source_config = data_source.mutable_config();
if (!IsChromeDataSource(source_config->name()))
return perfetto::BackendType::kSystemBackend;
}
return perfetto::BackendType::kCustomBackend;
}
return std::nullopt;
}
// Perfetto SDK build expects track_event data source to be configured via
// track_event_config. But some devtools users (e.g. Perfetto UI) send
// a chrome_config instead. We build a track_event_config based on the
// chrome_config if no other track_event data sources have been configured.
void ConvertToTrackEventConfigIfNeeded(perfetto::TraceConfig& trace_config) {
for (const auto& data_source : trace_config.data_sources()) {
if (!data_source.config().track_event_config_raw().empty()) {
return;
}
}
for (auto& data_source : *trace_config.mutable_data_sources()) {
if (data_source.config().name() ==
tracing::mojom::kTraceEventDataSourceName &&
data_source.config().has_chrome_config()) {
data_source.mutable_config()->set_name(kTrackEventDataSourceName);
base::trace_event::TraceConfig base_config(
data_source.config().chrome_config().trace_config());
bool privacy_filtering_enabled =
data_source.config().chrome_config().privacy_filtering_enabled();
data_source.mutable_config()->set_track_event_config_raw(
base_config.ToPerfettoTrackEventConfigRaw(privacy_filtering_enabled));
return;
}
}
}
// We currently don't support concurrent tracing sessions, but are planning to.
// For the time being, we're using this flag as a workaround to prevent devtools
// users from accidentally starting two concurrent sessions.
// TODO(eseckler): Remove once we add support for concurrent sessions to the
// perfetto backend.
static bool g_any_agent_tracing = false;
} // namespace
class TracingHandler::PerfettoTracingSession {
public:
PerfettoTracingSession(bool use_proto, perfetto::BackendType backend_type)
: use_proto_format_(use_proto), backend_type_(backend_type) {}
~PerfettoTracingSession() { g_any_agent_tracing = false; }
void EnableTracing(const perfetto::TraceConfig& perfetto_config,
base::OnceCallback<void(const std::string& /*error_msg*/)>
start_callback) {
DCHECK(!tracing_session_);
DCHECK(!tracing_active_);
g_any_agent_tracing = true;
tracing_active_ = true;
start_callback_ = std::move(start_callback);
#if DCHECK_IS_ON()
last_perfetto_config_ = perfetto_config;
for (auto& data_source : *(last_perfetto_config_.mutable_data_sources())) {
data_source.clear_producer_name_filter();
}
#endif
tracing_session_ = perfetto::Tracing::NewTrace(backend_type_);
tracing_session_->Setup(perfetto_config);
auto weak_ptr = weak_factory_.GetWeakPtr();
tracing_session_->SetOnStartCallback([weak_ptr] {
GetUIThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce(&PerfettoTracingSession::OnTracingSessionStarted,
weak_ptr));
});
tracing_session_->SetOnErrorCallback(
[weak_ptr](perfetto::TracingError error) {
GetUIThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce(&PerfettoTracingSession::OnTracingSessionFailed,
weak_ptr, error.message));
});
tracing_session_->Start();
}
void AdoptStartupTracingSession(
const perfetto::TraceConfig& perfetto_config) {
// Start a perfetto tracing session, which will claim startup tracing data.
DCHECK(!TracingController::GetInstance()->IsTracing());
waiting_for_startup_tracing_enabled_ = true;
EnableTracing(
perfetto_config,
base::BindOnce(&PerfettoTracingSession::OnStartupTracingEnabled,
base::Unretained(this)));
}
void ChangeTraceConfig(const perfetto::TraceConfig& perfetto_config) {
if (!tracing_session_)
return;
#if DCHECK_IS_ON()
// Ensure that the process filter is the only thing that gets changed
// in a configuration during a tracing session.
perfetto::TraceConfig config_without_filters = perfetto_config;
for (auto& data_source : *(config_without_filters.mutable_data_sources())) {
data_source.clear_producer_name_filter();
}
DCHECK(config_without_filters == last_perfetto_config_);
last_perfetto_config_ = std::move(config_without_filters);
#endif
tracing_session_->ChangeTraceConfig(perfetto_config);
}
void DisableTracing(
scoped_refptr<TracingController::TraceDataEndpoint> endpoint) {
DCHECK(endpoint);
if (waiting_for_startup_tracing_enabled_) {
pending_disable_tracing_task_ =
base::BindOnce(&PerfettoTracingSession::DisableTracing,
base::Unretained(this), std::move(endpoint));
return;
}
endpoint_ = endpoint;
tracing_active_ = false;
if (!tracing_session_) {
endpoint_->ReceivedTraceFinalContents();
return;
}
auto weak_ptr = weak_factory_.GetWeakPtr();
tracing_session_->SetOnStopCallback([weak_ptr] {
GetUIThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce(&PerfettoTracingSession::OnTracingSessionStopped,
weak_ptr));
});
tracing_session_->Stop();
}
void GetBufferUsage(base::OnceCallback<void(bool success,
float percent_full,
size_t approximate_event_count)>
on_buffer_usage_callback) {
DCHECK(on_buffer_usage_callback);
if (!tracing_session_) {
std::move(on_buffer_usage_callback).Run(false, 0.0f, 0);
return;
}
if (on_buffer_usage_callback_) {
// We only support one concurrent buffer usage request.
std::move(on_buffer_usage_callback).Run(false, 0.0f, 0);
return;
}
on_buffer_usage_callback_ = std::move(on_buffer_usage_callback);
auto weak_ptr = weak_factory_.GetWeakPtr();
tracing_session_->GetTraceStats(
[weak_ptr](perfetto::TracingSession::GetTraceStatsCallbackArgs args) {
tracing::ReadTraceStats(
args,
base::BindOnce(&PerfettoTracingSession::OnBufferUsage, weak_ptr),
GetUIThreadTaskRunner({}));
});
}
bool HasTracingFailed() { return tracing_active_ && !tracing_session_; }
bool HasDataLossOccurred() { return data_loss_; }
private:
void OnStartupTracingEnabled(const std::string& error_msg) {
DCHECK(error_msg.empty());
waiting_for_startup_tracing_enabled_ = false;
if (pending_disable_tracing_task_)
std::move(pending_disable_tracing_task_).Run();
}
void OnTracingSessionStarted() {
if (start_callback_)
std::move(start_callback_).Run(/*error_msg=*/std::string());
}
void OnTracingSessionFailed(std::string error_msg) {
tracing_session_.reset();
if (start_callback_)
std::move(start_callback_).Run(error_msg);
if (pending_disable_tracing_task_) {
// Will call endpoint_->ReceivedTraceFinalContents() and delete |this|.
std::move(pending_disable_tracing_task_).Run();
} else if (endpoint_) {
// Will delete |this|.
endpoint_->ReceivedTraceFinalContents();
}
}
void OnTracingSessionStopped() {
DCHECK(tracing_session_);
auto weak_ptr = weak_factory_.GetWeakPtr();
if (use_proto_format_) {
tracing_session_->ReadTrace(
[weak_ptr](perfetto::TracingSession::ReadTraceCallbackArgs args) {
tracing::ReadTraceAsProtobuf(
args,
base::BindOnce(&PerfettoTracingSession::OnTraceData, weak_ptr),
base::BindOnce(&PerfettoTracingSession::OnTraceDataComplete,
weak_ptr),
GetUIThreadTaskRunner({}));
});
} else {
// Ref-counted because it is used within the lambda running on the
// perfetto SDK's thread.
auto tokenizer = base::MakeRefCounted<
base::RefCountedData<std::unique_ptr<tracing::TracePacketTokenizer>>>(
std::make_unique<tracing::TracePacketTokenizer>());
tracing_session_->ReadTrace(
[weak_ptr,
tokenizer](perfetto::TracingSession::ReadTraceCallbackArgs args) {
tracing::ReadTraceAsJson(
args, tokenizer,
base::BindOnce(&PerfettoTracingSession::OnTraceData, weak_ptr),
base::BindOnce(&PerfettoTracingSession::OnTraceDataComplete,
weak_ptr),
GetUIThreadTaskRunner({}));
});
}
}
void OnBufferUsage(bool success, float percent_full, bool data_loss) {
data_loss_ |= data_loss;
if (on_buffer_usage_callback_) {
std::move(on_buffer_usage_callback_).Run(success, percent_full, 0);
}
}
void OnTraceData(std::unique_ptr<std::string> data) {
endpoint_->ReceiveTraceChunk(std::move(data));
}
void OnTraceDataComplete() {
// Request stats to check if data loss occurred.
GetBufferUsage(base::BindOnce(&PerfettoTracingSession::OnFinalBufferUsage,
weak_factory_.GetWeakPtr()));
}
void OnFinalBufferUsage(bool success,
float percent_full,
size_t approximate_event_count) {
// Will delete |this|.
endpoint_->ReceivedTraceFinalContents();
}
std::unique_ptr<perfetto::TracingSession> tracing_session_;
const bool use_proto_format_;
perfetto::BackendType backend_type_ =
perfetto::BackendType::kUnspecifiedBackend;
base::OnceCallback<void(const std::string&)> start_callback_;
base::OnceCallback<
void(bool success, float percent_full, size_t approximate_event_count)>
on_buffer_usage_callback_;
base::OnceClosure pending_disable_tracing_task_;
bool waiting_for_startup_tracing_enabled_ = false;
scoped_refptr<TracingController::TraceDataEndpoint> endpoint_;
bool tracing_active_ = false;
bool data_loss_ = false;
#if DCHECK_IS_ON()
perfetto::TraceConfig last_perfetto_config_;
#endif
base::WeakPtrFactory<PerfettoTracingSession> weak_factory_{this};
};
TracingHandler::TracingHandler(DevToolsAgentHostImpl* host,
DevToolsIOContext* io_context,
DevToolsSession* root_session)
: DevToolsDomainHandler(Tracing::Metainfo::domainName),
io_context_(io_context),
host_(host),
session_for_process_filter_(root_session),
did_initiate_recording_(false),
return_as_stream_(false),
gzip_compression_(false),
buffer_usage_reporting_interval_(0) {
video_consumer_ = std::make_unique<DevToolsVideoConsumer>(base::BindRepeating(
&TracingHandler::OnFrameFromVideoConsumer, base::Unretained(this)));
}
TracingHandler::~TracingHandler() = default;
// static
std::vector<TracingHandler*> TracingHandler::ForAgentHost(
DevToolsAgentHostImpl* host) {
return host->HandlersByName<TracingHandler>(Tracing::Metainfo::domainName);
}
void TracingHandler::Wire(UberDispatcher* dispatcher) {
frontend_ = std::make_unique<Tracing::Frontend>(dispatcher->channel());
Tracing::Dispatcher::wire(dispatcher, this);
}
Response TracingHandler::Disable() {
if (session_)
StopTracing(nullptr);
return Response::Success();
}
namespace {
class TracingNotification : public crdtp::Serializable {
public:
explicit TracingNotification(std::string json) : json_(std::move(json)) {}
void AppendSerialized(std::vector<uint8_t>* out) const override {
crdtp::Status status =
crdtp::json::ConvertJSONToCBOR(crdtp::SpanFrom(json_), out);
DCHECK(status.ok()) << status.ToASCIIString();
}
private:
std::string json_;
};
} // namespace
void TracingHandler::OnTraceDataCollected(
std::unique_ptr<std::string> trace_fragment) {
const std::string valid_trace_fragment =
UpdateTraceDataBuffer(*trace_fragment);
if (valid_trace_fragment.empty())
return;
// Hand-craft protocol notification message so we can substitute JSON
// that we already got as string as a bare object, not a quoted string.
std::string message(
"{ \"method\": \"Tracing.dataCollected\", \"params\": { \"value\": [");
const size_t messageSuffixSize = 10;
message.reserve(message.size() + valid_trace_fragment.size() +
messageSuffixSize - trace_data_buffer_state_.offset);
message.append(valid_trace_fragment.c_str() +
trace_data_buffer_state_.offset);
message += "] } }";
frontend_->sendRawNotification(
std::make_unique<TracingNotification>(std::move(message)));
}
void TracingHandler::OnTraceComplete() {
if (!trace_data_buffer_state_.data.empty())
OnTraceDataCollected(std::make_unique<std::string>(""));
DCHECK(trace_data_buffer_state_.data.empty());
DCHECK_EQ(0u, trace_data_buffer_state_.pos);
DCHECK_EQ(0, trace_data_buffer_state_.open_braces);
DCHECK(!trace_data_buffer_state_.in_string);
DCHECK(!trace_data_buffer_state_.slashed);
bool data_loss = session_->HasDataLossOccurred();
process_set_monitor_.reset();
session_.reset();
frontend_->TracingComplete(data_loss);
}
std::string TracingHandler::UpdateTraceDataBuffer(
const std::string& trace_fragment) {
size_t end = 0;
size_t last_open = 0;
TraceDataBufferState& state = trace_data_buffer_state_;
state.offset = 0;
bool update_offset = state.open_braces == 0;
for (; state.pos < trace_fragment.size(); ++state.pos) {
char c = trace_fragment[state.pos];
switch (c) {
case '{':
if (!state.in_string && !state.slashed) {
state.open_braces++;
if (state.open_braces == 1) {
last_open = state.data.size() + state.pos;
if (update_offset) {
state.offset = last_open;
update_offset = false;
}
}
}
break;
case '}':
if (!state.in_string && !state.slashed) {
DCHECK_GT(state.open_braces, 0);
state.open_braces--;
if (state.open_braces == 0)
end = state.data.size() + state.pos + 1;
}
break;
case '"':
if (!state.slashed)
state.in_string = !state.in_string;
break;
case 'u':
if (state.slashed)
state.pos += 4;
break;
}
if (state.in_string && c == '\\') {
state.slashed = !state.slashed;
} else {
state.slashed = false;
}
}
// Next starting position is usually 0 except when we are in the middle of
// processing a unicode character, i.e. \uxxxx.
state.pos -= trace_fragment.size();
std::string complete_str = state.data + trace_fragment;
state.data = complete_str.substr(std::max(end, last_open));
complete_str.resize(end);
return complete_str;
}
void TracingHandler::OnTraceToStreamComplete(const std::string& stream_handle) {
bool data_loss = session_->HasDataLossOccurred();
process_set_monitor_.reset();
session_.reset();
std::string stream_format = (proto_format_ ? Tracing::StreamFormatEnum::Proto
: Tracing::StreamFormatEnum::Json);
std::string stream_compression =
(gzip_compression_ ? Tracing::StreamCompressionEnum::Gzip
: Tracing::StreamCompressionEnum::None);
frontend_->TracingComplete(data_loss, stream_handle, stream_format,
stream_compression);
}
void TracingHandler::Start(Maybe<std::string> categories,
Maybe<std::string> options,
Maybe<double> buffer_usage_reporting_interval,
Maybe<std::string> transfer_mode,
Maybe<std::string> transfer_format,
Maybe<std::string> transfer_compression,
Maybe<Tracing::TraceConfig> config,
Maybe<Binary> perfetto_config,
Maybe<std::string> tracing_backend,
std::unique_ptr<StartCallback> callback) {
bool return_as_stream = transfer_mode.value_or("") ==
Tracing::Start::TransferModeEnum::ReturnAsStream;
bool gzip_compression =
transfer_compression.value_or("") == Tracing::StreamCompressionEnum::Gzip;
bool proto_format =
transfer_format.value_or("") == Tracing::StreamFormatEnum::Proto;
perfetto::TraceConfig trace_config;
if (perfetto_config.has_value()) {
bool parsed = trace_config.ParseFromArray(perfetto_config.value().data(),
perfetto_config.value().size());
if (!parsed) {
callback->sendFailure(Response::InvalidParams(
"Couldn't parse the supplied perfettoConfig."));
return;
}
if (!trace_config.data_sources_size()) {
callback->sendFailure(Response::InvalidParams(
"Supplied perfettoConfig doesn't have any data sources specified"));
return;
}
// Default to proto format for perfettoConfig, except if it specifies
// convert_to_legacy_json in the data source config.
proto_format = true;
for (const auto& data_source : trace_config.data_sources()) {
if (data_source.config().has_chrome_config() &&
data_source.config().chrome_config().convert_to_legacy_json()) {
proto_format = false;
break;
}
}
ConvertToTrackEventConfigIfNeeded(trace_config);
} else {
base::trace_event::TraceConfig browser_config =
base::trace_event::TraceConfig();
if (config.has_value()) {
base::Value::Dict dict;
CHECK(crdtp::ConvertProtocolValue(config.value(), &dict));
browser_config =
GetTraceConfigFromDevToolsConfig(base::Value(std::move(dict)));
} else if (categories.has_value() || options.has_value()) {
browser_config = base::trace_event::TraceConfig(categories.value_or(""),
options.value_or(""));
}
trace_config = CreatePerfettoConfiguration(browser_config, return_as_stream,
proto_format);
}
std::optional<perfetto::BackendType> backend = GetBackendTypeFromParameters(
tracing_backend.value_or(Tracing::TracingBackendEnum::Auto),
trace_config);
if (!backend) {
callback->sendFailure(Response::InvalidParams(
"Unsupported value for tracing_backend parameter."));
return;
}
// Check if we should adopt the startup tracing session. Only the first
// Tracing.start() sent to the browser endpoint can adopt it.
// TODO(crbug.com/40171330): Add tests for system-controlled startup traces.
AttemptAdoptStartupSession(return_as_stream, gzip_compression, proto_format,
*backend);
if (IsTracing()) {
callback->sendFailure(Response::ServerError(
"Tracing has already been started (possibly in another tab)."));
return;
}
if (did_initiate_recording_) {
callback->sendFailure(Response::ServerError(
"Starting trace recording is already in progress"));
return;
}
if (config.has_value() && (categories.has_value() || options.has_value())) {
callback->sendFailure(Response::InvalidParams(
"Either trace config (preferred), or categories+options should be "
"specified, but not both."));
return;
}
if (proto_format && !return_as_stream) {
callback->sendFailure(Response::InvalidParams(
"Proto format is only supported when using stream transfer mode."));
return;
}
return_as_stream_ = return_as_stream;
gzip_compression_ = gzip_compression;
proto_format_ = proto_format;
buffer_usage_reporting_interval_ =
buffer_usage_reporting_interval.value_or(0);
did_initiate_recording_ = true;
trace_config_ = std::move(trace_config);
if (session_for_process_filter_) {
process_set_monitor_ = TracingProcessSetMonitor::Start(
*session_for_process_filter_,
base::BindRepeating(&TracingHandler::AddProcessToFilter,
base::Unretained(this)));
std::unordered_set<base::ProcessId> pids = process_set_monitor_->GetPids();
base::ProcessId browser_pid = base::Process::Current().Pid();
pids.insert(browser_pid);
if (auto* gpu_process_host =
GpuProcessHost::Get(GPU_PROCESS_KIND_SANDBOXED,
/* force_create */ false)) {
base::ProcessId gpu_pid = gpu_process_host->process_id();
if (gpu_pid != base::kNullProcessId) {
pids.insert(gpu_pid);
}
}
AddPidsToProcessFilter(pids, trace_config_);
}
session_ = std::make_unique<PerfettoTracingSession>(proto_format_, *backend);
session_->EnableTracing(
trace_config_,
base::BindOnce(&TracingHandler::OnRecordingEnabled,
weak_factory_.GetWeakPtr(), std::move(callback)));
}
perfetto::TraceConfig TracingHandler::CreatePerfettoConfiguration(
const base::trace_event::TraceConfig& browser_config,
bool return_as_stream,
bool proto_format) {
return tracing::GetDefaultPerfettoConfig(
browser_config,
/*privacy_filtering_enabled=*/false,
/*convert_to_legacy_json=*/!proto_format,
perfetto::protos::gen::ChromeConfig::USER_INITIATED,
/*json_agent_label_filter*/
(proto_format || return_as_stream)
? ""
: tracing::mojom::kChromeTraceEventLabel);
}
void TracingHandler::AddProcessToFilter(base::ProcessId pid) {
CHECK(did_initiate_recording_);
CHECK(session_);
AddPidsToProcessFilter({pid}, trace_config_);
session_->ChangeTraceConfig(trace_config_);
}
void TracingHandler::AttemptAdoptStartupSession(
bool return_as_stream,
bool gzip_compression,
bool proto_format,
perfetto::BackendType tracing_backend) {
// Only adopt startup session for browser-level sessions.
if (session_for_process_filter_) {
return;
}
auto& startup_config = tracing::TraceStartupConfig::GetInstance();
if (!startup_config.AttemptAdoptBySessionOwner(
tracing::TraceStartupConfig::SessionOwner::kDevToolsTracingHandler)) {
return;
}
return_as_stream_ = return_as_stream;
gzip_compression_ = gzip_compression;
proto_format_ = proto_format;
perfetto::TraceConfig perfetto_config =
tracing::TraceStartupConfig::GetInstance().GetPerfettoConfig();
session_ =
std::make_unique<PerfettoTracingSession>(proto_format_, tracing_backend);
session_->AdoptStartupTracingSession(perfetto_config);
}
Response TracingHandler::End() {
if (!session_) {
did_initiate_recording_ = false;
return Response::ServerError("Tracing is not started");
}
if (session_->HasTracingFailed())
return Response::ServerError("Tracing failed");
scoped_refptr<TracingController::TraceDataEndpoint> endpoint;
if (return_as_stream_) {
endpoint = new DevToolsStreamEndpoint(
weak_factory_.GetWeakPtr(),
DevToolsStreamFile::Create(
io_context_, gzip_compression_ || proto_format_ /* binary */));
if (gzip_compression_) {
endpoint = TracingControllerImpl::CreateCompressedStringEndpoint(
endpoint, true /* compress_with_background_priority */);
}
} else {
// Reset the trace data buffer state.
trace_data_buffer_state_ = TracingHandler::TraceDataBufferState();
endpoint = new DevToolsTraceEndpointProxy(weak_factory_.GetWeakPtr());
}
StopTracing(endpoint);
return Response::Success();
}
void TracingHandler::GetCategories(
std::unique_ptr<GetCategoriesCallback> callback) {
// TODO(eseckler): Support this via the perfetto service too.
TracingController::GetInstance()->GetCategories(
base::BindOnce(&TracingHandler::OnCategoriesReceived,
weak_factory_.GetWeakPtr(), std::move(callback)));
}
void TracingHandler::OnRecordingEnabled(std::unique_ptr<StartCallback> callback,
const std::string& error_msg) {
if (!error_msg.empty()) {
callback->sendFailure(Response::ServerError(error_msg));
return;
}
if (!did_initiate_recording_) {
callback->sendFailure(Response::ServerError(
"Tracing was stopped before start has been completed."));
return;
}
EmitFrameTree();
callback->sendSuccess();
SetupTimer(buffer_usage_reporting_interval_);
bool screenshot_enabled;
TRACE_EVENT_CATEGORY_GROUP_ENABLED(
TRACE_DISABLED_BY_DEFAULT("devtools.screenshot"), &screenshot_enabled);
if (screenshot_enabled) {
// Reset number of screenshots received, each time tracing begins.
number_of_screenshots_from_video_consumer_ = 0;
if (WebContents* wc = host_ ? host_->GetWebContents() : nullptr) {
auto* frame_host =
static_cast<RenderFrameHostImpl*>(wc->GetPrimaryMainFrame());
video_consumer_->SetFrameSinkId(
frame_host->GetRenderWidgetHost()->GetFrameSinkId());
}
video_consumer_->SetMinAndMaxFrameSize(kMinFrameSize, kMaxFrameSize);
video_consumer_->StartCapture();
}
}
void TracingHandler::OnBufferUsage(bool success,
float percent_full,
size_t approximate_event_count) {
if (!did_initiate_recording_)
return;
if (!success)
return;
// TODO(crbug426117): remove set_value once all clients have switched to
// the new interface of the event.
frontend_->BufferUsage(percent_full, approximate_event_count, percent_full);
}
void TracingHandler::OnCategoriesReceived(
std::unique_ptr<GetCategoriesCallback> callback,
const std::set<std::string>& category_set) {
auto categories = std::make_unique<protocol::Array<std::string>>(
category_set.begin(), category_set.end());
callback->sendSuccess(std::move(categories));
}
void TracingHandler::RequestMemoryDump(
Maybe<bool> deterministic,
Maybe<std::string> level_of_detail,
std::unique_ptr<RequestMemoryDumpCallback> callback) {
if (!IsTracing()) {
callback->sendFailure(Response::ServerError("Tracing is not started"));
return;
}
std::optional<base::trace_event::MemoryDumpLevelOfDetail> memory_detail =
StringToMemoryDumpLevelOfDetail(level_of_detail.value_or(
Tracing::MemoryDumpLevelOfDetailEnum::Detailed));
if (!memory_detail) {
callback->sendFailure(
Response::ServerError("Invalid levelOfDetail specified."));
return;
}
auto determinism = deterministic.value_or(false)
? base::trace_event::MemoryDumpDeterminism::kForceGc
: base::trace_event::MemoryDumpDeterminism::kNone;
auto on_memory_dump_finished =
base::BindOnce(&TracingHandler::OnMemoryDumpFinished,
weak_factory_.GetWeakPtr(), std::move(callback));
memory_instrumentation::MemoryInstrumentation::GetInstance()
->RequestGlobalDumpAndAppendToTrace(
base::trace_event::MemoryDumpType::kExplicitlyTriggered,
*memory_detail, determinism, std::move(on_memory_dump_finished));
}
void TracingHandler::OnMemoryDumpFinished(
std::unique_ptr<RequestMemoryDumpCallback> callback,
bool success,
uint64_t dump_id) {
callback->sendSuccess(base::StringPrintf("0x%" PRIx64, dump_id), success);
}
void TracingHandler::OnFrameFromVideoConsumer(
scoped_refptr<media::VideoFrame> frame) {
if (!IsTracing()) {
return;
}
const SkBitmap skbitmap = DevToolsVideoConsumer::GetSkBitmapFromFrame(frame);
uint64_t frame_sequence = *frame->metadata().frame_sequence;
// This reference_time is an ESTIMATE. It is set by the compositor frame sink
// from the `expected_display_time`, which is based on a previously known
// frame start PLUS the vsync interval (eg 16.6ms)
base::TimeTicks expected_display_time = *frame->metadata().reference_time;
TRACE_EVENT_OBJECT_SNAPSHOT_WITH_ID_AND_TIMESTAMP(
TRACE_DISABLED_BY_DEFAULT("devtools.screenshot"), "Screenshot",
frame_sequence, expected_display_time,
std::make_unique<DevToolsTraceableScreenshot>(skbitmap));
++number_of_screenshots_from_video_consumer_;
DCHECK(video_consumer_);
if (number_of_screenshots_from_video_consumer_ >=
DevToolsTraceableScreenshot::kMaximumNumberOfScreenshots) {
video_consumer_->StopCapture();
}
}
Response TracingHandler::RecordClockSyncMarker(const std::string& sync_id) {
if (!IsTracing())
return Response::ServerError("Tracing is not started");
TRACE_EVENT_CLOCK_SYNC_RECEIVER(sync_id);
return Response::Success();
}
void TracingHandler::SetupTimer(double usage_reporting_interval) {
if (usage_reporting_interval == 0)
return;
if (usage_reporting_interval < kMinimumReportingInterval)
usage_reporting_interval = kMinimumReportingInterval;
base::TimeDelta interval =
base::Milliseconds(std::ceil(usage_reporting_interval));
buffer_usage_poll_timer_ = std::make_unique<base::RepeatingTimer>();
buffer_usage_poll_timer_->Start(
FROM_HERE, interval,
base::BindRepeating(&TracingHandler::UpdateBufferUsage,
weak_factory_.GetWeakPtr()));
}
void TracingHandler::UpdateBufferUsage() {
session_->GetBufferUsage(base::BindOnce(&TracingHandler::OnBufferUsage,
weak_factory_.GetWeakPtr()));
}
void TracingHandler::StopTracing(
const scoped_refptr<TracingController::TraceDataEndpoint>& endpoint) {
DCHECK(session_);
buffer_usage_poll_timer_.reset();
process_set_monitor_.reset();
if (endpoint) {
// Will delete |session_|.
session_->DisableTracing(std::move(endpoint));
} else {
session_.reset();
}
did_initiate_recording_ = false;
video_consumer_->StopCapture();
}
bool TracingHandler::IsTracing() const {
return TracingController::GetInstance()->IsTracing() || g_any_agent_tracing;
}
void TracingHandler::EmitFrameTree() {
auto data = std::make_unique<base::trace_event::TracedValue>();
if (WebContents* wc = host_ ? host_->GetWebContents() : nullptr) {
auto* frame_host =
static_cast<RenderFrameHostImpl*>(wc->GetPrimaryMainFrame());
CHECK(frame_host);
data->SetInteger(
"frameTreeNodeId",
frame_host->frame_tree_node()->frame_tree_node_id().value());
data->SetBoolean("persistentIds", true);
data->BeginArray("frames");
wc->ForEachRenderFrameHost([&data](RenderFrameHost* rfh) {
data->BeginDictionary();
FillFrameData(data.get(), static_cast<RenderFrameHostImpl*>(rfh),
rfh->GetLastCommittedURL());
data->EndDictionary();
});
data->EndArray();
}
TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"),
"TracingStartedInBrowser", TRACE_EVENT_SCOPE_THREAD,
"data", std::move(data));
}
void TracingHandler::WillInitiatePrerender(FrameTreeNode* frame_tree_node) {
if (!did_initiate_recording_) {
return;
}
auto data = std::make_unique<base::trace_event::TracedValue>();
FillFrameData(data.get(), frame_tree_node->current_frame_host(),
frame_tree_node->current_url());
TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"),
"FrameCommittedInBrowser", TRACE_EVENT_SCOPE_THREAD,
"data", std::move(data));
}
void TracingHandler::ReadyToCommitNavigation(
NavigationRequest* navigation_request) {
if (!did_initiate_recording_)
return;
auto data = std::make_unique<base::trace_event::TracedValue>();
RenderFrameHostImpl* frame_host = navigation_request->GetRenderFrameHost();
FillFrameData(data.get(), frame_host, navigation_request->GetURL());
TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"),
"FrameCommittedInBrowser", TRACE_EVENT_SCOPE_THREAD,
"data", std::move(data));
if (frame_host->IsOutermostMainFrame()) {
video_consumer_->SetFrameSinkId(navigation_request->GetRenderFrameHost()
->GetRenderWidgetHost()
->GetFrameSinkId());
}
}
void TracingHandler::FrameDeleted(FrameTreeNodeId frame_tree_node_id) {
if (!did_initiate_recording_)
return;
FrameTreeNode* node = FrameTreeNode::GloballyFindByID(frame_tree_node_id);
if (!node->current_frame_host()) {
// This might happen on prerendering activation when the prerender tree is
// shutting how and the RFH is migrated to a different frame tree.
return;
}
auto data = std::make_unique<base::trace_event::TracedValue>();
data->SetString(
"frame", node->current_frame_host()->devtools_frame_token().ToString());
TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"),
"FrameDeletedInBrowser", TRACE_EVENT_SCOPE_THREAD,
"data", std::move(data));
}
// static
bool TracingHandler::IsStartupTracingActive() {
return ::tracing::TraceStartupConfig::GetInstance().IsEnabled();
}
// static
base::trace_event::TraceConfig TracingHandler::GetTraceConfigFromDevToolsConfig(
const base::Value& devtools_config) {
base::Value config = ConvertDictKeyStyle(devtools_config);
base::Value::Dict& config_dict = config.GetDict();
if (std::string* mode = config_dict.FindString(kRecordModeParam)) {
config_dict.Set(kRecordModeParam, ConvertFromCamelCase(*mode, '-'));
}
if (std::optional<double> buffer_size =
config_dict.FindDouble(kTraceBufferSizeInKb)) {
config_dict.Set(
kTraceBufferSizeInKb,
static_cast<int>(base::saturated_cast<size_t>(buffer_size.value())));
}
return base::trace_event::TraceConfig(config_dict);
}
} // namespace content::protocol