Changeset 116226 in webkit

Timestamp:

May 5, 2012 12:38:46 PM (12 years ago)

Author:

jonlee@apple.com

Message:

[WK2] Incoming events may be processed out-of-order
​https://bugs.webkit.org/show_bug.cgi?id=85696
<rdar://problem/11386129>

Reviewed by Maciej Stachowiak.

All messages go to a single queue that gets iterated over by dispatchMessages(). If an input
event arrives in the middle of a flood of messages, all of them will be dispatched before the
input event is dispatched.

In other words, the first dispatchMessages() call will process all of the messages in the queue,
and all subsequent dispatchMessages() calls will act as no-ops, since there is nothing in the queue.

To fix this, we rename dispatchMessages to dispatchOneMessage, and only process one message at a
time.

• Platform/CoreIPC/Connection.h: Rename dispatchMessages() to dispatchOneMessage().
• Platform/CoreIPC/Connection.cpp:

(CoreIPC::Connection::enqueueIncomingMessage): Dispatch a call to dispatchOneMessage() on the
run loop.
(CoreIPC::Connection::dispatchOneMessage): Remove the while(true) loop.

Location:

trunk/Source/WebKit2

Files:

• ChangeLog (modified) (1 diff)
• Platform/CoreIPC/Connection.cpp (modified) (2 diffs)
• Platform/CoreIPC/Connection.h (modified) (1 diff)

trunk/Source/WebKit2/ChangeLog

@@ +1 @@
+2012-05-04  Jon Lee  <jonlee@apple.com>
+
+        [WK2] Incoming events may be processed out-of-order
+        https://bugs.webkit.org/show_bug.cgi?id=85696
+        <rdar://problem/11386129>
+
+        Reviewed by Maciej Stachowiak.
+
+        All messages go to a single queue that gets iterated over by dispatchMessages(). If an input
+        event arrives in the middle of a flood of messages, all of them will be dispatched before the
+        input event is dispatched.
+
+        In other words, the first dispatchMessages() call will process all of the messages in the queue,
+        and all subsequent dispatchMessages() calls will act as no-ops, since there is nothing in the queue.
+
+        To fix this, we rename dispatchMessages to dispatchOneMessage, and only process one message at a
+        time.
+
+        * Platform/CoreIPC/Connection.h: Rename dispatchMessages() to dispatchOneMessage().
+        * Platform/CoreIPC/Connection.cpp:
+        (CoreIPC::Connection::enqueueIncomingMessage): Dispatch a call to dispatchOneMessage() on the
+        run loop.
+        (CoreIPC::Connection::dispatchOneMessage): Remove the while(true) loop.
+
 2012-05-04  Gustavo Noronha Silva  <gns@gnome.org>
 

trunk/Source/WebKit2/Platform/CoreIPC/Connection.cpp

@@ -667 +667 @@
     m_incomingMessages.append(incomingMessage);
 
-    m_clientRunLoop->dispatch(bind(&Connection::dispatchMessages, this));
+    m_clientRunLoop->dispatch(bind(&Connection::dispatchOneMessage, this));
 }
 
@@ -704 +704 @@
 }
 
-void Connection::dispatchMessages()
-{
-    while (true) {
-        IncomingMessage incomingMessage;
-
-        {
-            MutexLocker locker(m_incomingMessagesLock);
-            if (m_incomingMessages.isEmpty())
-                break;
-
-            incomingMessage = m_incomingMessages.takeFirst();
-        }
-
-        dispatchMessage(incomingMessage);
-    }
+void Connection::dispatchOneMessage()
+{
+    IncomingMessage incomingMessage;
+
+    {
+        MutexLocker locker(m_incomingMessagesLock);
+        if (m_incomingMessages.isEmpty())
+            return;
+
+        incomingMessage = m_incomingMessages.takeFirst();
+    }
+
+    dispatchMessage(incomingMessage);
 }
 

trunk/Source/WebKit2/Platform/CoreIPC/Connection.h

@@ -239 +239 @@
     void dispatchConnectionDidClose();
     void dispatchMessage(IncomingMessage&);
-    void dispatchMessages();
+    void dispatchOneMessage();
     void dispatchSyncMessage(MessageID, ArgumentDecoder*);
     void didFailToSendSyncMessage();