Changeset 66552 in webkit

Timestamp:

Aug 31, 2010 4:21:57 PM (14 years ago)

Author:

Beth Dakin

Message:

Fix for ​https://bugs.webkit.org/show_bug.cgi?id=44828 FrameView
should make more calls to postLayoutTasks() using the timer
-and corresponding-
<rdar://problem/8064938>

Reviewed by Dave Hyatt.

WebCore:

This change only allows synchronous calls to postLayoutTasks() if
we are not already in a synchronous call to postLayoutTasks().
Furthermore, it de-couples the notion of "the post layout timer
should fire" from m_postLayoutTasksTimer.isActive(), instead using
a boolean to track the need to use the timer.

• page/FrameView.cpp:

(WebCore::FrameView::FrameView):
(WebCore::FrameView::~FrameView):
(WebCore::FrameView::reset):
(WebCore::FrameView::layout):
(WebCore::FrameView::unscheduleRelayout):
(WebCore::FrameView::performPostLayoutTasks):

• page/FrameView.h:

LayoutTests:

• fast/events/change-overflow-on-overflow-change-expected.txt: Added.
• fast/events/change-overflow-on-overflow-change.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/fast/events/change-overflow-on-overflow-change-expected.txt (added)
• LayoutTests/fast/events/change-overflow-on-overflow-change.html (added)
• WebCore/ChangeLog (modified) (1 diff)
• WebCore/page/FrameView.cpp (modified) (7 diffs)
• WebCore/page/FrameView.h (modified) (1 diff)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2010-08-31  Beth Dakin  <bdakin@apple.com>
+
+        Reviewed by Dave Hyatt.
+
+        Fix for https://bugs.webkit.org/show_bug.cgi?id=44828 FrameView 
+        should make more calls to postLayoutTasks() using the timer
+        -and corresponding-
+        <rdar://problem/8064938>
+
+        * fast/events/change-overflow-on-overflow-change-expected.txt: Added.
+        * fast/events/change-overflow-on-overflow-change.html: Added.
+
 2010-08-31  Alexey Proskuryakov  <ap@apple.com>
 

trunk/WebCore/ChangeLog

@@ +1 @@
+2010-08-31  Beth Dakin  <bdakin@apple.com>
+
+        Reviewed by Dave Hyatt.
+
+        Fix for https://bugs.webkit.org/show_bug.cgi?id=44828 FrameView 
+        should make more calls to postLayoutTasks() using the timer
+        -and corresponding-
+        <rdar://problem/8064938>
+
+        This change only allows synchronous calls to postLayoutTasks() if 
+        we are not already in a synchronous call to postLayoutTasks(). 
+        Furthermore, it de-couples the notion of "the post layout timer 
+        should fire" from m_postLayoutTasksTimer.isActive(), instead using 
+        a boolean to track the need to use the timer.
+
+        * page/FrameView.cpp:
+        (WebCore::FrameView::FrameView):
+        (WebCore::FrameView::~FrameView):
+        (WebCore::FrameView::reset):
+        (WebCore::FrameView::layout):
+        (WebCore::FrameView::unscheduleRelayout):
+        (WebCore::FrameView::performPostLayoutTasks):
+        * page/FrameView.h:
+
 2010-08-30  Anders Carlsson  <andersca@apple.com>
 

trunk/WebCore/page/FrameView.cpp

@@ -129 +129 @@
     , m_layoutTimer(this, &FrameView::layoutTimerFired)
     , m_layoutRoot(0)
+    , m_shouldFirePostLayoutTimer(false)
+    , m_inSynchronousPostLayout(false)
     , m_postLayoutTasksTimer(this, &FrameView::postLayoutTimerFired)
     , m_isTransparent(false)
@@ -165 +167 @@
 FrameView::~FrameView()
 {
-    if (m_postLayoutTasksTimer.isActive()) {
+    if (m_shouldFirePostLayoutTimer) {
         m_postLayoutTasksTimer.stop();
         m_scheduledEvents.clear();
@@ -205 +207 @@
     m_layoutSchedulingEnabled = true;
     m_inLayout = false;
+    m_inSynchronousPostLayout = false;
+    m_shouldFirePostLayoutTimer = false;
     m_layoutCount = 0;
     m_nestedLayoutCount = 0;
@@ -639 +643 @@
     m_layoutSchedulingEnabled = false;
 
-    if (!m_nestedLayoutCount && m_postLayoutTasksTimer.isActive()) {
+    if (!m_nestedLayoutCount && !m_inSynchronousPostLayout && m_shouldFirePostLayoutTimer) {
         // This is a new top-level layout. If there are any remaining tasks from the previous
         // layout, finish them now.
+        m_inSynchronousPostLayout = true;
         m_postLayoutTasksTimer.stop();
         performPostLayoutTasks();
+        m_inSynchronousPostLayout = false;
     }
 
@@ -822 +828 @@
                              layoutHeight() < contentsHeight());
 
-    if (!m_postLayoutTasksTimer.isActive()) {
-        // Calls resumeScheduledEvents()
-        performPostLayoutTasks();
-
-        if (!m_postLayoutTasksTimer.isActive() && needsLayout()) {
-            // Post-layout widget updates or an event handler made us need layout again.
-            // Lay out again, but this time defer widget updates and event dispatch until after
-            // we return.
+    if (!m_shouldFirePostLayoutTimer) {
+        if (!m_inSynchronousPostLayout) {
+            m_inSynchronousPostLayout = true;
+            // Calls resumeScheduledEvents()
+            performPostLayoutTasks();
+            m_inSynchronousPostLayout = false;
+        }
+
+        if (!m_shouldFirePostLayoutTimer && (needsLayout() || m_inSynchronousPostLayout)) {
+            // If we need layout or are already in a synchronous call to postLayoutTasks(), 
+            // defer widget updates and event dispatch until after we return. postLayoutTasks()
+            // can make us need to update again, and we can get stuck in a nasty cycle unless
+            // we call it through the timer here.
+            m_shouldFirePostLayoutTimer = true;
             m_postLayoutTasksTimer.startOneShot(0);
-            pauseScheduledEvents();
-            layout();
+            if (needsLayout()) {
+                pauseScheduledEvents();
+                layout();
+            }
         }
     } else {
@@ -1453 +1467 @@
 void FrameView::unscheduleRelayout()
 {
+    m_postLayoutTasksTimer.stop();
+
     if (!m_layoutTimer.isActive())
         return;
@@ -1596 +1612 @@
 void FrameView::performPostLayoutTasks()
 {
+    m_shouldFirePostLayoutTimer = false;
+
     if (m_firstLayoutCallbackPending) {
         m_firstLayoutCallbackPending = false;

trunk/WebCore/page/FrameView.h

@@ -320 +320 @@
     bool m_layoutSchedulingEnabled;
     bool m_inLayout;
+    bool m_shouldFirePostLayoutTimer;
+    bool m_inSynchronousPostLayout;
     int m_layoutCount;
     unsigned m_nestedLayoutCount;