Changeset 139781 in webkit

Timestamp:

Jan 15, 2013, 1:40:29 PM (12 years ago)

Author:

dominik.rottsches@intel.com

Message:

[CoordinatedGraphics] Deadlock when running abspos-child-container-changes-from-relative-to-static.html
​https://bugs.webkit.org/show_bug.cgi?id=106884

Reviewed by Benjamin Poulain.

We need to return false if m_waitingForUIProcess is true since otherwise
we'll not really repaint in performScheduledLayerFlush() and the
UI process will wait forever. Returning false leads to executing the layer flush
synchronously and immediately, then acknowledging the
callback to the WebProcess - which resolves the deadlock.

• WebProcess/WebPage/CoordinatedGraphics/CoordinatedLayerTreeHost.cpp:

(WebKit::CoordinatedLayerTreeHost::forceRepaintAsync): Return false in order to trigger a synchronous repaint if m_waitingForUIProcess is true.

Location:

trunk/Source/WebKit2

Files:

• ChangeLog (modified) (1 diff)
• WebProcess/WebPage/CoordinatedGraphics/CoordinatedLayerTreeHost.cpp (modified) (1 diff)

trunk/Source/WebKit2/ChangeLog

@@ +1 @@
+2013-01-15  Dominik Röttsches  <dominik.rottsches@intel.com>
+
+        [CoordinatedGraphics] Deadlock when running abspos-child-container-changes-from-relative-to-static.html
+        https://bugs.webkit.org/show_bug.cgi?id=106884
+
+        Reviewed by Benjamin Poulain.
+
+        We need to return false if m_waitingForUIProcess is true since otherwise
+        we'll not really repaint in performScheduledLayerFlush() and the
+        UI process will wait forever. Returning false leads to executing the layer flush
+        synchronously and immediately, then acknowledging the
+        callback to the WebProcess - which resolves the deadlock.
+
+        * WebProcess/WebPage/CoordinatedGraphics/CoordinatedLayerTreeHost.cpp:
+        (WebKit::CoordinatedLayerTreeHost::forceRepaintAsync): Return false in order to trigger a synchronous repaint if m_waitingForUIProcess is true.
+
 2013-01-15  Simon Fraser  <simon.fraser@apple.com>
 

trunk/Source/WebKit2/WebProcess/WebPage/CoordinatedGraphics/CoordinatedLayerTreeHost.cpp

@@ -205 +205 @@
 bool CoordinatedLayerTreeHost::forceRepaintAsync(uint64_t callbackID)
 {
+    // Avoid deadlocks when the UI process has requested a forceRepaint by falling back to a synchronous repaint, see caller WebPage::forceRepaint.
+    if (m_waitingForUIProcess)
+        return false;
+
     // We expect the UI process to not require a new repaint until the previous one has finished.
     ASSERT(!m_forceRepaintAsyncCallbackID);