1 // Copyright 2016 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "base/trace_event/blame_context.h"
6
7 #include "base/strings/stringprintf.h"
8 #include "base/trace_event/trace_event.h"
9 #include "base/trace_event/trace_event_argument.h"
10
11 namespace base {
12 namespace trace_event {
13
BlameContext(const char * category,const char * name,const char * type,const char * scope,int64_t id,const BlameContext * parent_context)14 BlameContext::BlameContext(const char* category,
15 const char* name,
16 const char* type,
17 const char* scope,
18 int64_t id,
19 const BlameContext* parent_context)
20 : category_(category),
21 name_(name),
22 type_(type),
23 scope_(scope),
24 id_(id),
25 parent_scope_(parent_context ? parent_context->scope() : nullptr),
26 parent_id_(parent_context ? parent_context->id() : 0),
27 category_group_enabled_(nullptr),
28 weak_factory_(this) {
29 DCHECK(!parent_context || !std::strcmp(name_, parent_context->name()))
30 << "Parent blame context must have the same name";
31 }
32
~BlameContext()33 BlameContext::~BlameContext() {
34 DCHECK(thread_checker_.CalledOnValidThread());
35 DCHECK(WasInitialized());
36 TRACE_EVENT_API_ADD_TRACE_EVENT(
37 TRACE_EVENT_PHASE_DELETE_OBJECT, category_group_enabled_, type_, scope_,
38 id_, 0, nullptr, nullptr, nullptr, nullptr, TRACE_EVENT_FLAG_HAS_ID);
39 trace_event::TraceLog::GetInstance()->RemoveAsyncEnabledStateObserver(this);
40 }
41
Enter()42 void BlameContext::Enter() {
43 DCHECK(WasInitialized());
44 TRACE_EVENT_API_ADD_TRACE_EVENT(TRACE_EVENT_PHASE_ENTER_CONTEXT,
45 category_group_enabled_, name_, scope_, id_,
46 0 /* num_args */, nullptr, nullptr, nullptr,
47 nullptr, TRACE_EVENT_FLAG_HAS_ID);
48 }
49
Leave()50 void BlameContext::Leave() {
51 DCHECK(WasInitialized());
52 TRACE_EVENT_API_ADD_TRACE_EVENT(TRACE_EVENT_PHASE_LEAVE_CONTEXT,
53 category_group_enabled_, name_, scope_, id_,
54 0 /* num_args */, nullptr, nullptr, nullptr,
55 nullptr, TRACE_EVENT_FLAG_HAS_ID);
56 }
57
TakeSnapshot()58 void BlameContext::TakeSnapshot() {
59 DCHECK(thread_checker_.CalledOnValidThread());
60 DCHECK(WasInitialized());
61 if (!*category_group_enabled_)
62 return;
63 std::unique_ptr<trace_event::TracedValue> snapshot(
64 new trace_event::TracedValue);
65 AsValueInto(snapshot.get());
66 static const char* const kArgName = "snapshot";
67 const int kNumArgs = 1;
68 unsigned char arg_types[1] = {TRACE_VALUE_TYPE_CONVERTABLE};
69 std::unique_ptr<trace_event::ConvertableToTraceFormat> arg_values[1] = {
70 std::move(snapshot)};
71 TRACE_EVENT_API_ADD_TRACE_EVENT(TRACE_EVENT_PHASE_SNAPSHOT_OBJECT,
72 category_group_enabled_, type_, scope_, id_,
73 kNumArgs, &kArgName, arg_types, nullptr,
74 arg_values, TRACE_EVENT_FLAG_HAS_ID);
75 }
76
OnTraceLogEnabled()77 void BlameContext::OnTraceLogEnabled() {
78 DCHECK(WasInitialized());
79 TakeSnapshot();
80 }
81
OnTraceLogDisabled()82 void BlameContext::OnTraceLogDisabled() {}
83
AsValueInto(trace_event::TracedValue * state)84 void BlameContext::AsValueInto(trace_event::TracedValue* state) {
85 DCHECK(WasInitialized());
86 if (!parent_id_)
87 return;
88 state->BeginDictionary("parent");
89 state->SetString("id_ref", StringPrintf("0x%" PRIx64, parent_id_));
90 state->SetString("scope", parent_scope_);
91 state->EndDictionary();
92 }
93
Initialize()94 void BlameContext::Initialize() {
95 DCHECK(thread_checker_.CalledOnValidThread());
96 category_group_enabled_ =
97 TRACE_EVENT_API_GET_CATEGORY_GROUP_ENABLED(category_);
98 TRACE_EVENT_API_ADD_TRACE_EVENT(
99 TRACE_EVENT_PHASE_CREATE_OBJECT, category_group_enabled_, type_, scope_,
100 id_, 0, nullptr, nullptr, nullptr, nullptr, TRACE_EVENT_FLAG_HAS_ID);
101 trace_event::TraceLog::GetInstance()->AddAsyncEnabledStateObserver(
102 weak_factory_.GetWeakPtr());
103 TakeSnapshot();
104 }
105
WasInitialized() const106 bool BlameContext::WasInitialized() const {
107 return category_group_enabled_ != nullptr;
108 }
109
110 } // namespace trace_event
111 } // namespace base
112