Changeset 286634 in webkit

Timestamp:

Dec 7, 2021, 5:35:15 PM (5 years ago)

Author:

Cameron McCormack

Message:

Move shouldAutoActivateFontIfNeeded knownFamilies cache to FontCache
​https://bugs.webkit.org/show_bug.cgi?id=233749

Reviewed by Myles Maxfield.

With OffscreenCanvas, we can call shouldAutoActivateFontIfNeeded on a
worker thread, and the knownFamilies HashSet is not thread safe. Also,
the AtomStrings it stores are thread-specific. Move it to FontCache, so
each thread has its own set.

• platform/graphics/FontCache.h:
• platform/graphics/cocoa/FontCacheCoreText.cpp:

(WebCore::FontCache::shouldAutoActivateFontIfNeeded):
(WebCore::shouldAutoActivateFontIfNeeded): Deleted.

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/FontCache.h (modified) (2 diffs)
• platform/graphics/cocoa/FontCacheCoreText.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2021-12-07  Cameron McCormack  <heycam@apple.com>
+
+        Move shouldAutoActivateFontIfNeeded knownFamilies cache to FontCache
+        https://bugs.webkit.org/show_bug.cgi?id=233749
+
+        Reviewed by Myles Maxfield.
+
+        With OffscreenCanvas, we can call shouldAutoActivateFontIfNeeded on a
+        worker thread, and the knownFamilies HashSet is not thread safe. Also,
+        the AtomStrings it stores are thread-specific. Move it to FontCache, so
+        each thread has its own set.
+
+        * platform/graphics/FontCache.h:
+        * platform/graphics/cocoa/FontCacheCoreText.cpp:
+        (WebCore::FontCache::shouldAutoActivateFontIfNeeded):
+        (WebCore::shouldAutoActivateFontIfNeeded): Deleted.
+
 2021-12-07  Devin Rousso  <drousso@apple.com>
 

trunk/Source/WebCore/platform/graphics/FontCache.h

@@ -375 +375 @@
     static std::optional<ASCIILiteral> platformAlternateFamilyName(const String&);
 
+#if PLATFORM(MAC)
+    bool shouldAutoActivateFontIfNeeded(const AtomString& family);
+#endif
+
     Timer m_purgeTimer;
     
@@ -388 +392 @@
 #if PLATFORM(IOS_FAMILY)
     RecursiveLock m_fontLock;
+#endif
+
+#if PLATFORM(MAC)
+    HashSet<AtomString> m_knownFamilies;
 #endif
 

trunk/Source/WebCore/platform/graphics/cocoa/FontCacheCoreText.cpp

@@ -1339 +1339 @@
 
 #if PLATFORM(MAC)
-static bool shouldAutoActivateFontIfNeeded(const AtomString& family)
-{
-#ifndef NDEBUG
-    // This cache is not thread safe so the following assertion is there to
-    // make sure this function is always called from the same thread.
-    static Thread* initThread = &Thread::current();
-    ASSERT(initThread == &Thread::current());
-#endif
-
-    static NeverDestroyed<HashSet<AtomString>> knownFamilies;
+bool FontCache::shouldAutoActivateFontIfNeeded(const AtomString& family)
+{
     static const unsigned maxCacheSize = 128;
-    ASSERT(knownFamilies.get().size() <= maxCacheSize);
-    if (knownFamilies.get().size() == maxCacheSize)
-        knownFamilies.get().remove(knownFamilies.get().random());
+    ASSERT(m_knownFamilies.size() <= maxCacheSize);
+    if (m_knownFamilies.size() == maxCacheSize)
+        m_knownFamilies.remove(m_knownFamilies.random());
 
     // Only attempt to auto-activate fonts once for performance reasons.
-    return knownFamilies.get().add(family).isNewEntry;
+    return m_knownFamilies.add(family).isNewEntry;
 }