Changeset 216069 in webkit

Timestamp:

May 2, 2017, 7:30:30 AM (8 years ago)

Author:

Antti Koivisto

Message:

Document style resolvers should share user rulesets
​https://bugs.webkit.org/show_bug.cgi?id=171549

Reviewed by Andreas Kling.

Large user stylesheets (like those used by ad blockers) can end up using lots of memory if
a document uses large number of shadow trees. User style is inherently per-document and
the resulting rulesets can be shared between the document and the shadow trees.

• css/DocumentRuleSets.cpp:

(WebCore::DocumentRuleSets::DocumentRuleSets):
(WebCore::DocumentRuleSets::userStyle):

Return per-document user style for shadow trees.

(WebCore::DocumentRuleSets::collectFeatures):

• css/DocumentRuleSets.h:

(WebCore::DocumentRuleSets::setUsesSharedUserStyle):
(WebCore::DocumentRuleSets::userStyle): Deleted.

• css/StyleResolver.cpp:

(WebCore::StyleResolver::StyleResolver):
(WebCore::StyleResolver::initializeUserStyle):

Separate user style initialization from construction.

• css/StyleResolver.h:
• style/StyleScope.cpp:

(WebCore::Style::Scope::resolver):

Don't initialize user style for user agents shadow trees.

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• css/DocumentRuleSets.cpp (modified) (3 diffs)
• css/DocumentRuleSets.h (modified) (3 diffs)
• css/StyleResolver.cpp (modified) (3 diffs)
• css/StyleResolver.h (modified) (1 diff)
• style/StyleScope.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2017-05-02  Antti Koivisto  <antti@apple.com>
+
+        Document style resolvers should share user rulesets
+        https://bugs.webkit.org/show_bug.cgi?id=171549
+
+        Reviewed by Andreas Kling.
+
+        Large user stylesheets (like those used by ad blockers) can end up using lots of memory if
+        a document uses large number of shadow trees. User style is inherently per-document and
+        the resulting rulesets can be shared between the document and the shadow trees.
+
+        * css/DocumentRuleSets.cpp:
+        (WebCore::DocumentRuleSets::DocumentRuleSets):
+        (WebCore::DocumentRuleSets::userStyle):
+
+            Return per-document user style for shadow trees.
+
+        (WebCore::DocumentRuleSets::collectFeatures):
+        * css/DocumentRuleSets.h:
+        (WebCore::DocumentRuleSets::setUsesSharedUserStyle):
+        (WebCore::DocumentRuleSets::userStyle): Deleted.
+        * css/StyleResolver.cpp:
+        (WebCore::StyleResolver::StyleResolver):
+        (WebCore::StyleResolver::initializeUserStyle):
+
+            Separate user style initialization from construction.
+
+        * css/StyleResolver.h:
+        * style/StyleScope.cpp:
+        (WebCore::Style::Scope::resolver):
+
+            Don't initialize user style for user agents shadow trees.
+
 2017-05-02  Gwang Yoon Hwang  <yoon@igalia.com>
 

trunk/Source/WebCore/css/DocumentRuleSets.cpp

@@ -38 +38 @@
 namespace WebCore {
 
-DocumentRuleSets::DocumentRuleSets()
+DocumentRuleSets::DocumentRuleSets(StyleResolver& styleResolver)
+    : m_styleResolver(styleResolver)
 {
     m_authorStyle = std::make_unique<RuleSet>();
@@ -46 +47 @@
 DocumentRuleSets::~DocumentRuleSets()
 {
+}
+
+RuleSet* DocumentRuleSets::userStyle() const
+{
+    if (m_usesSharedUserStyle)
+        return m_styleResolver.document().styleScope().resolver().ruleSets().userStyle();
+    return m_userStyle.get();
 }
 
@@ -113 +121 @@
     if (m_authorStyle)
         m_features.add(m_authorStyle->features());
-    if (m_userStyle)
-        m_features.add(m_userStyle->features());
+    if (auto* userStyle = this->userStyle())
+        m_features.add(userStyle->features());
 
     m_siblingRuleSet = makeRuleSet(m_features.siblingRules);

trunk/Source/WebCore/css/DocumentRuleSets.h

@@ -41 +41 @@
 class DocumentRuleSets {
 public:
-    DocumentRuleSets();
+    DocumentRuleSets(StyleResolver&);
     ~DocumentRuleSets();
-    
+
     bool isAuthorStyleDefined() const { return m_isAuthorStyleDefined; }
     RuleSet& authorStyle() const { return *m_authorStyle.get(); }
-    RuleSet* userStyle() const { return m_userStyle.get(); }
+    RuleSet* userStyle() const;
     const RuleFeatureSet& features() const;
     RuleSet* sibling() const { return m_siblingRuleSet.get(); }
@@ -60 +60 @@
     const AttributeRules* ancestorAttributeRulesForHTML(const AtomicString&) const;
 
+    void setUsesSharedUserStyle(bool b) { m_usesSharedUserStyle = true; }
     void initUserStyle(ExtensionStyleSheets&, const MediaQueryEvaluator&, StyleResolver&);
+
     void resetAuthorStyle();
     void appendAuthorStyleSheets(const Vector<RefPtr<CSSStyleSheet>>&, MediaQueryEvaluator*, InspectorCSSOMWrappers&, StyleResolver*);
@@ -73 +75 @@
     std::unique_ptr<RuleSet> m_authorStyle;
     std::unique_ptr<RuleSet> m_userStyle;
+    bool m_usesSharedUserStyle { false };
 
+    StyleResolver& m_styleResolver;
     mutable RuleFeatureSet m_features;
     mutable unsigned m_defaultStyleVersionOnFeatureCollection { 0 };

trunk/Source/WebCore/css/StyleResolver.cpp

@@ -229 +229 @@
 
 StyleResolver::StyleResolver(Document& document)
-    : m_matchedPropertiesCacheAdditionsSinceLastSweep(0)
+    : m_ruleSets(*this)
+    , m_matchedPropertiesCacheAdditionsSinceLastSweep(0)
     , m_matchedPropertiesCacheSweepTimer(*this, &StyleResolver::sweepMatchedPropertiesCache)
     , m_document(document)
@@ -268 +269 @@
     m_ruleSets.resetAuthorStyle();
 
-    m_ruleSets.initUserStyle(m_document.extensionStyleSheets(), m_mediaQueryEvaluator, *this);
-
 #if ENABLE(SVG_FONTS)
     if (m_document.svgExtensions()) {
@@ -277 +276 @@
     }
 #endif
+}
+
+void StyleResolver::initializeUserStyle()
+{
+    m_ruleSets.initUserStyle(m_document.extensionStyleSheets(), m_mediaQueryEvaluator, *this);
 }
 

trunk/Source/WebCore/css/StyleResolver.h

@@ -153 +153 @@
     const Settings& settings() const { return m_document.settings(); }
 
+    void initializeUserStyle();
     void appendAuthorStyleSheets(const Vector<RefPtr<CSSStyleSheet>>&);
 

trunk/Source/WebCore/style/StyleScope.cpp

@@ -97 +97 @@
         SetForScope<bool> isUpdatingStyleResolver { m_isUpdatingStyleResolver, true };
         m_resolver = std::make_unique<StyleResolver>(m_document);
+
+        if (!m_shadowRoot)
+            m_resolver->initializeUserStyle();
+        else if (m_shadowRoot->mode() != ShadowRootMode::UserAgent)
+            m_resolver->ruleSets().setUsesSharedUserStyle();
+
         m_resolver->appendAuthorStyleSheets(m_activeStyleSheets);
     }