Track parse time blocked on script in xml documents.

third_party/WebKit/Source/core/xml/parser/XMLDocumentParser.cpp

 /*
  * Copyright (C) 2000 Peter Kelly (pmk@post.com)
  * Copyright (C) 2005, 2006, 2008, 2014 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2007 Samuel Weinig (sam@webkit.org)
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008 Holger Hans Peter Freyther
  * Copyright (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 18 matching lines @@
 #include "bindings/core/v8/ExceptionStatePlaceholder.h"
 #include "bindings/core/v8/ScriptController.h"
 #include "bindings/core/v8/ScriptSourceCode.h"
 #include "bindings/core/v8/V8Document.h"
 #include "core/HTMLNames.h"
 #include "core/XMLNSNames.h"
 #include "core/dom/CDATASection.h"
 #include "core/dom/Comment.h"
 #include "core/dom/Document.h"
 #include "core/dom/DocumentFragment.h"
+#include "core/dom/DocumentParserTiming.h"
 #include "core/dom/DocumentType.h"
 #include "core/dom/ProcessingInstruction.h"
 #include "core/dom/ScriptLoader.h"
 #include "core/dom/StyleEngine.h"
 #include "core/dom/TransformSource.h"
 #include "core/fetch/FetchInitiatorTypeNames.h"
 #include "core/fetch/RawResource.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/fetch/ScriptResource.h"
 #include "core/frame/LocalFrame.h"
@@ skipping 343 matching lines @@
 
     // Mutation event handlers executed by appendData() might detach this parser.
     return !isStopped();
 }
 
 void XMLDocumentParser::detach()
 {
     if (m_pendingScript) {
         m_pendingScript->removeClient(this);
         m_pendingScript = nullptr;
+        m_parserBlockingPendingScriptLoadStartTime = 0.0;
     }
     clearCurrentNodeStack();
     ScriptableDocumentParser::detach();
 }
 
 void XMLDocumentParser::end()
 {
     TRACE_EVENT0("blink", "XMLDocumentParser::end");
     // XMLDocumentParserLibxml2 will do bad things to the document if doEnd() is called.
     // I don't believe XMLDocumentParserQt needs doEnd called in the fragment case.
@@ skipping 43 matching lines @@
     m_xmlErrors.insertErrorMessageBlock();
 }
 
 void XMLDocumentParser::notifyFinished(Resource* unusedResource)
 {
     ASSERT_UNUSED(unusedResource, unusedResource == m_pendingScript);
 
     ScriptSourceCode sourceCode(m_pendingScript.get());
     bool errorOccurred = m_pendingScript->errorOccurred();
     bool wasCanceled = m_pendingScript->wasCanceled();
+    double scriptParserBlockingTime = m_parserBlockingPendingScriptLoadStartTime;
+    m_parserBlockingPendingScriptLoadStartTime = 0.0;
 
     m_pendingScript->removeClient(this);
     m_pendingScript = nullptr;
 
     Element* e = m_scriptElement;
     m_scriptElement = nullptr;
 
     ScriptLoader* scriptLoader = toScriptLoaderIfPossible(e);
     ASSERT(scriptLoader);
 
     if (errorOccurred) {
         scriptLoader->dispatchErrorEvent();
     } else if (!wasCanceled) {
+        if (scriptParserBlockingTime > 0.0) {
+            DocumentParserTiming::from(*document()).recordParserBlockedOnScriptLoadDuration(monotonicallyIncreasingTime() - scriptParserBlockingTime, scriptLoader->wasCreatedDuringDocumentWrite());

[kouhei (in TOK), 2016/08/12 01:13:29]

Can we record this to separate UMA?
XMLDocumentParser script loader code is quite different from HTMLDocumentParser.

+        }
+
         if (!scriptLoader->executeScript(sourceCode))
             scriptLoader->dispatchErrorEvent();
         else
             scriptLoader->dispatchLoadEvent();
     }
 
     m_scriptElement = nullptr;
 
     if (!isDetached() && !m_requestingScript)
         resumeParsing();
@@ skipping 282 matching lines @@
     , m_sawError(false)
     , m_sawCSS(false)
     , m_sawXSLTransform(false)
     , m_sawFirstElement(false)
     , m_isXHTMLDocument(false)
     , m_parserPaused(false)
     , m_requestingScript(false)
     , m_finishCalled(false)
     , m_xmlErrors(&document)
     , m_scriptStartPosition(TextPosition::belowRangePosition())
+    , m_parserBlockingPendingScriptLoadStartTime(0.0)
     , m_parsingFragment(false)
 {
     // This is XML being used as a document resource.
     if (frameView && document.isXMLDocument())
         UseCounter::count(document, UseCounter::XMLDocument);
 }
 
 XMLDocumentParser::XMLDocumentParser(DocumentFragment* fragment, Element* parentElement, ParserContentPolicy parserContentPolicy)
     : ScriptableDocumentParser(fragment->document(), parserContentPolicy)
     , m_hasView(false)
@@ skipping 296 matching lines @@
         // the libxml2 and Qt XMLDocumentParser implementations.
 
 
         if (scriptLoader->readyToBeParserExecuted()) {
             if (!scriptLoader->executeScript(ScriptSourceCode(scriptLoader->scriptContent(), document()->url(), m_scriptStartPosition))) {
                 scriptLoader->dispatchErrorEvent();
                 return;
             }
         } else if (scriptLoader->willBeParserExecuted()) {
             m_pendingScript = scriptLoader->resource();
+            DCHECK_EQ(m_parserBlockingPendingScriptLoadStartTime, 0.0);
+            m_parserBlockingPendingScriptLoadStartTime = monotonicallyIncreasingTime();
             m_scriptElement = element;
             m_pendingScript->addClient(this);
             // m_pendingScript will be 0 if script was already loaded and
             // addClient() executed it.
             if (m_pendingScript)
                 pauseParsing();
         } else {
             m_scriptElement = nullptr;
         }
 
@@ skipping 534 matching lines @@
     sax.initialized = XML_SAX2_MAGIC;
     RefPtr<XMLParserContext> parser = XMLParserContext::createStringParser(&sax, &state);
     String parseString = "<?xml version=\"1.0\"?><attrs " + string + " />";
     parseChunk(parser->context(), parseString);
     finishParsing(parser->context());
     attrsOK = state.gotAttributes;
     return state.attributes;
 }
 
 } // namespace blink