DevTools: Move worker reporting out of InspectorTraceAgent

The agent is going to be removed soon.

The ExecutionContextWorkerRegistry is made responsible for reporting workers.
Each worker is reported as a trace event when a worker starts.
Also all previously registred workers are reported on trace start.

Change-Id: I3cde31ae74e991ad522c476b606bee3c0a5f8587
Reviewed-on: https://chromium-review.googlesource.com/1038684Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#555294}

third_party/blink/renderer/core/inspector/inspector_tracing_agent.cc

@@ -8,8 +8,6 @@
 #include "third_party/blink/renderer/core/inspector/identifiers_factory.h"
 #include "third_party/blink/renderer/core/inspector/inspected_frames.h"
 #include "third_party/blink/renderer/core/inspector/inspector_trace_events.h"
-#include "third_party/blink/renderer/core/workers/execution_context_worker_registry.h"
-#include "third_party/blink/renderer/core/workers/worker_inspector_proxy.h"
 #include "third_party/blink/renderer/platform/instrumentation/tracing/trace_event.h"
 
 namespace blink {
@@ -38,23 +36,8 @@ void InspectorTracingAgent::Trace(blink::Visitor* visitor) {
 
 void InspectorTracingAgent::Restore() {
   state_->getString(TracingAgentState::kSessionId, &session_id_);
-  if (IsStarted()) {
-    instrumenting_agents_->addInspectorTracingAgent(this);
+  if (IsStarted())
     EmitMetadataEvents();
-  }
-}
-
-void InspectorTracingAgent::DidStartWorker(WorkerInspectorProxy* proxy, bool) {
-  // For now we assume this is document. TODO(kinuko): Fix this.
-  DCHECK(proxy->GetExecutionContext()->IsDocument());
-  LocalFrame* frame = ToDocument(proxy->GetExecutionContext())->GetFrame();
-  if (proxy->GetWorkerThread() && frame && inspected_frames_->Contains(frame)) {
-    TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"),
-                         "TracingSessionIdForWorker", TRACE_EVENT_SCOPE_THREAD,
-                         "data",
-                         InspectorTracingSessionIdForWorkerEvent::Data(
-                             frame, proxy->Url(), proxy->GetWorkerThread()));
-  }
 }
 
 void InspectorTracingAgent::start(Maybe<String> categories,
@@ -71,7 +54,6 @@ void InspectorTracingAgent::start(Maybe<String> categories,
     return;
   }
 
-  instrumenting_agents_->addInspectorTracingAgent(this);
   session_id_ = IdentifiersFactory::CreateIdentifier();
   state_->setString(TracingAgentState::kSessionId, session_id_);
 
@@ -101,14 +83,6 @@ void InspectorTracingAgent::EmitMetadataEvents() {
                        TRACE_EVENT_SCOPE_THREAD, "data",
                        InspectorTracingStartedInFrame::Data(
                            session_id_, inspected_frames_->Root()));
-
-  for (LocalFrame* frame : *inspected_frames_) {
-    for (WorkerInspectorProxy* proxy :
-         ExecutionContextWorkerRegistry::From(*frame->GetDocument())
-             ->GetWorkerInspectorProxies()) {
-      DidStartWorker(proxy, false);
-    }
-  }
 }
 
 Response InspectorTracingAgent::disable() {
@@ -117,7 +91,6 @@ Response InspectorTracingAgent::disable() {
 }
 
 void InspectorTracingAgent::InnerDisable() {
-  instrumenting_agents_->removeInspectorTracingAgent(this);
   state_->remove(TracingAgentState::kSessionId);
   session_id_ = String();
 }

third_party/blink/renderer/core/inspector/inspector_tracing_agent.h

@@ -11,13 +11,11 @@
 #include "third_party/blink/renderer/core/core_export.h"
 #include "third_party/blink/renderer/core/inspector/inspector_base_agent.h"
 #include "third_party/blink/renderer/core/inspector/protocol/Tracing.h"
-#include "third_party/blink/renderer/core/loader/frame_loader_types.h"
 #include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"
 
 namespace blink {
 
 class InspectedFrames;
-class WorkerInspectorProxy;
 
 class CORE_EXPORT InspectorTracingAgent final
     : public InspectorBaseAgent<protocol::Tracing::Metainfo> {
@@ -31,9 +29,6 @@ class CORE_EXPORT InspectorTracingAgent final
   void Restore() override;
   protocol::Response disable() override;
 
-  // InspectorInstrumentation methods
-  void DidStartWorker(WorkerInspectorProxy*, bool);
-
   // Protocol method implementations.
   void start(protocol::Maybe<String> categories,
              protocol::Maybe<String> options,

third_party/blink/renderer/core/probe/CoreProbes.json5

@@ -203,11 +203,6 @@
         "willSendRequest",
       ]
     },
-    Tracing: {
-      probes: [
-        "didStartWorker",
-      ]
-    },
     Worker: {
       probes: [
         "didStartWorker",

third_party/blink/renderer/core/workers/execution_context_worker_registry.cc

@@ -4,6 +4,8 @@
 
 #include "third_party/blink/renderer/core/workers/execution_context_worker_registry.h"
 
+#include "third_party/blink/renderer/core/inspector/inspector_trace_events.h"
+
 namespace blink {
 
 const char ExecutionContextWorkerRegistry::kSupplementName[] =
@@ -11,7 +13,13 @@ const char ExecutionContextWorkerRegistry::kSupplementName[] =
 
 ExecutionContextWorkerRegistry::ExecutionContextWorkerRegistry(
     ExecutionContext& context)
-    : Supplement<ExecutionContext>(context) {}
+    : Supplement<ExecutionContext>(context), weak_factory_(this) {
+  TraceEvent::AddAsyncEnabledStateObserver(weak_factory_.GetWeakPtr());
+}
+
+ExecutionContextWorkerRegistry::~ExecutionContextWorkerRegistry() {
+  TraceEvent::RemoveAsyncEnabledStateObserver(this);
+}
 
 ExecutionContextWorkerRegistry* ExecutionContextWorkerRegistry::From(
     ExecutionContext& context) {
@@ -29,6 +37,7 @@ ExecutionContextWorkerRegistry* ExecutionContextWorkerRegistry::From(
 void ExecutionContextWorkerRegistry::AddWorkerInspectorProxy(
     WorkerInspectorProxy* proxy) {
   proxies_.insert(proxy);
+  EmitTraceEvent(proxy);
 }
 
 void ExecutionContextWorkerRegistry::RemoveWorkerInspectorProxy(
@@ -41,6 +50,25 @@ ExecutionContextWorkerRegistry::GetWorkerInspectorProxies() {
   return proxies_;
 }
 
+void ExecutionContextWorkerRegistry::OnTraceLogEnabled() {
+  for (WorkerInspectorProxy* proxy : proxies_)
+    EmitTraceEvent(proxy);
+}
+
+void ExecutionContextWorkerRegistry::OnTraceLogDisabled() {}
+
+void ExecutionContextWorkerRegistry::EmitTraceEvent(
+    WorkerInspectorProxy* proxy) {
+  ExecutionContext* context = GetSupplementable();
+  LocalFrame* frame =
+      context->IsDocument() ? ToDocument(context)->GetFrame() : nullptr;
+  TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"),
+                       "TracingSessionIdForWorker", TRACE_EVENT_SCOPE_THREAD,
+                       "data",
+                       InspectorTracingSessionIdForWorkerEvent::Data(
+                           frame, proxy->Url(), proxy->GetWorkerThread()));
+}
+
 void ExecutionContextWorkerRegistry::Trace(Visitor* visitor) {
   visitor->Trace(proxies_);
   Supplement<ExecutionContext>::Trace(visitor);

third_party/blink/renderer/core/workers/execution_context_worker_registry.h

@@ -7,6 +7,7 @@
 
 #include "third_party/blink/renderer/core/execution_context/execution_context.h"
 #include "third_party/blink/renderer/core/workers/worker_inspector_proxy.h"
+#include "third_party/blink/renderer/platform/instrumentation/tracing/trace_event.h"
 #include "third_party/blink/renderer/platform/supplementable.h"
 #include "third_party/blink/renderer/platform/wtf/hash_set.h"
 
@@ -15,6 +16,7 @@ namespace blink {
 // Tracks the WorkerInspectorProxy objects created by a given ExecutionContext.
 class ExecutionContextWorkerRegistry final
     : public GarbageCollectedFinalized<ExecutionContextWorkerRegistry>,
+      public TraceEvent::AsyncEnabledStateObserver,
       public Supplement<ExecutionContext> {
   USING_GARBAGE_COLLECTED_MIXIN(ExecutionContextWorkerRegistry);
 
@@ -23,16 +25,25 @@ class ExecutionContextWorkerRegistry final
 
   static ExecutionContextWorkerRegistry* From(ExecutionContext& context);
 
+  ~ExecutionContextWorkerRegistry() override;
+
   void AddWorkerInspectorProxy(WorkerInspectorProxy* proxy);
   void RemoveWorkerInspectorProxy(WorkerInspectorProxy* proxy);
   const HeapHashSet<Member<WorkerInspectorProxy>>& GetWorkerInspectorProxies();
 
+  // blink::TraceEvent::AsyncEnabledStateObserver implementation:
+  void OnTraceLogEnabled() override;
+  void OnTraceLogDisabled() override;
+
   void Trace(Visitor* visitor) override;
 
  private:
   explicit ExecutionContextWorkerRegistry(ExecutionContext& context);
 
+  void EmitTraceEvent(WorkerInspectorProxy* proxy);
+
   HeapHashSet<Member<WorkerInspectorProxy>> proxies_;
+  base::WeakPtrFactory<ExecutionContextWorkerRegistry> weak_factory_;
 };
 
 }  // namespace blink

third_party/blink/renderer/platform/instrumentation/tracing/trace_event.cc

@@ -19,5 +19,16 @@ void DisableTracing() {
   base::trace_event::TraceLog::GetInstance()->SetDisabled();
 }
 
+void AddAsyncEnabledStateObserver(
+    base::WeakPtr<AsyncEnabledStateObserver> observer) {
+  base::trace_event::TraceLog::GetInstance()->AddAsyncEnabledStateObserver(
+      observer);
+}
+
+void RemoveAsyncEnabledStateObserver(AsyncEnabledStateObserver* observer) {
+  base::trace_event::TraceLog::GetInstance()->RemoveAsyncEnabledStateObserver(
+      observer);
+}
+
 }  // namespace TraceEvent
 }  // namespace blink

third_party/blink/renderer/platform/instrumentation/tracing/trace_event.h

@@ -29,6 +29,8 @@ namespace blink {
 namespace TraceEvent {
 
 using base::trace_event::TraceScopedTrackableObject;
+using AsyncEnabledStateObserver =
+    base::trace_event::TraceLog::AsyncEnabledStateObserver;
 
 inline base::TimeTicks ToTraceTimestamp(double seconds) {
   return base::TimeTicks() + base::TimeDelta::FromSecondsD(seconds);
@@ -40,6 +42,11 @@ void ToTraceTimestamp(int64_t);
 PLATFORM_EXPORT void EnableTracing(const String& category_filter);
 PLATFORM_EXPORT void DisableTracing();
 
+PLATFORM_EXPORT void AddAsyncEnabledStateObserver(
+    base::WeakPtr<AsyncEnabledStateObserver>);
+PLATFORM_EXPORT void RemoveAsyncEnabledStateObserver(
+    AsyncEnabledStateObserver*);
+
 }  // namespace TraceEvent
 }  // namespace blink