Assertion failure in LayerFlushScheduler::resume() when running some …

…layout tests in WebKitTestRunner https://bugs.webkit.org/show_bug.cgi?id=72535 Reviewed by Anders Carlsson. LayerFlushScheduler attempted to use a counter strategy for calls to suspend() and resume(), which allowed us to assert that these calls were balanced. Unfortunately it is hard to guarantee this in WebKit2, where we sometimes try to call suspend() before we've entered compositing mode (hence before we have a LayerTreeHost and a LayerFlushScheduler). When we later call resume(), this call ends up being unbalanced and asserts. For now, remove the assertions and allow unbalanced calls to suspend() and resume(). * platform/graphics/ca/LayerFlushScheduler.cpp: (WebCore::LayerFlushScheduler::suspend): (WebCore::LayerFlushScheduler::resume): * platform/graphics/ca/LayerFlushScheduler.h: * platform/graphics/ca/mac/LayerFlushSchedulerMac.cpp: (WebCore::LayerFlushScheduler::LayerFlushScheduler): (WebCore::LayerFlushScheduler::runLoopObserverCallback): (WebCore::LayerFlushScheduler::schedule): Canonical link: https://commits.webkit.org/89018@main git-svn-id: https://svn.webkit.org/repository/webkit/trunk@100492 268f45cc-cd09-0410-ab3c-d52691b4dbfc
WebKit · Nov 16, 2011 · 649cb39 · 649cb39
1 parent 514f746
commit 649cb39
Show file tree

Hide file tree

Showing 4 changed files with 39 additions and 11 deletions.
diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
@@ -1,3 +1,30 @@
+2011-11-16  Andy Estes  <aestes@apple.com>
+
+        Assertion failure in LayerFlushScheduler::resume() when running some layout tests in WebKitTestRunner
+        https://bugs.webkit.org/show_bug.cgi?id=72535
+
+        Reviewed by Anders Carlsson.
+
+        LayerFlushScheduler attempted to use a counter strategy for calls to
+        suspend() and resume(), which allowed us to assert that these calls
+        were balanced. Unfortunately it is hard to guarantee this in WebKit2,
+        where we sometimes try to call suspend() before we've entered
+        compositing mode (hence before we have a LayerTreeHost and a
+        LayerFlushScheduler). When we later call resume(), this call ends up
+        being unbalanced and asserts.
+
+        For now, remove the assertions and allow unbalanced calls to suspend()
+        and resume().
+
+        * platform/graphics/ca/LayerFlushScheduler.cpp:
+        (WebCore::LayerFlushScheduler::suspend):
+        (WebCore::LayerFlushScheduler::resume):
+        * platform/graphics/ca/LayerFlushScheduler.h:
+        * platform/graphics/ca/mac/LayerFlushSchedulerMac.cpp:
+        (WebCore::LayerFlushScheduler::LayerFlushScheduler):
+        (WebCore::LayerFlushScheduler::runLoopObserverCallback):
+        (WebCore::LayerFlushScheduler::schedule):
+
 2011-11-16  Sheriff Bot  <webkit.review.bot@gmail.com>
 
         Unreviewed, rolling out r100473.

diff --git a/Source/WebCore/platform/graphics/ca/LayerFlushScheduler.cpp b/Source/WebCore/platform/graphics/ca/LayerFlushScheduler.cpp
@@ -33,19 +33,20 @@ namespace WebCore {
 
 void LayerFlushScheduler::suspend()
 {
-    if (!m_suspendCount)
-        invalidate();
+    if (m_isSuspended)
+        return;
 
-    ++m_suspendCount;
+    m_isSuspended = true;
+    invalidate();
 }
 
 void LayerFlushScheduler::resume()
 {
-    ASSERT(m_suspendCount);
-    --m_suspendCount;
+    if (!m_isSuspended)
+        return;
 
-    if (!m_suspendCount)
-        schedule();
+    m_isSuspended = false;
+    schedule();
 }
 
 } // namespace WebCore

diff --git a/Source/WebCore/platform/graphics/ca/LayerFlushScheduler.h b/Source/WebCore/platform/graphics/ca/LayerFlushScheduler.h
@@ -47,7 +47,7 @@ class LayerFlushScheduler {
     void resume();
 
 private:
-    unsigned int m_suspendCount;
+    bool m_isSuspended;
     LayerFlushSchedulerClient* m_client;
 
 #if PLATFORM(MAC)

diff --git a/Source/WebCore/platform/graphics/ca/mac/LayerFlushSchedulerMac.cpp b/Source/WebCore/platform/graphics/ca/mac/LayerFlushSchedulerMac.cpp
@@ -35,7 +35,7 @@ static const CFIndex CoreAnimationRunLoopOrder = 2000000;
 static const CFIndex LayerFlushRunLoopOrder = CoreAnimationRunLoopOrder - 1;
 
 LayerFlushScheduler::LayerFlushScheduler(LayerFlushSchedulerClient* client)
-    : m_suspendCount(0)
+    : m_isSuspended(false)
     , m_client(client)
 {
     ASSERT_ARG(client, client);
@@ -50,13 +50,13 @@ void LayerFlushScheduler::runLoopObserverCallback(CFRunLoopObserverRef, CFRunLoo
 {
     LayerFlushScheduler* layerFlushScheduler = static_cast<LayerFlushScheduler*>(context);
     ASSERT(layerFlushScheduler->m_runLoopObserver);
-    ASSERT(!layerFlushScheduler->m_suspendCount);
+    ASSERT(!layerFlushScheduler->m_isSuspended);
     layerFlushScheduler->m_client->flushLayers();
 }
 
 void LayerFlushScheduler::schedule()
 {
-    if (m_suspendCount)
+    if (m_isSuspended)
         return;
 
     CFRunLoopRef currentRunLoop = CFRunLoopGetCurrent();