Fixed events benchmark postEvent function

The postEvent function was causing problems in Symbian because it
couldn't handle multiple iterations of the benchmark.

- Moved event allocation inside QBENCHMARK so that each iteration will
  have a fresh event object.
- Added resetting of the PingPong counters inside QBENCHMARK.
- Used QTestEventLoop::instance().exitLoop() instead of
  QCoreApplication::quit() to make the cases beyond first
  to actually test something meaningful.
- Added a "first time" case to postEvent_data, as the first time the
  event loop is used it takes much longer that the subsequent times,
  at least in Symbian, so that skewed the results.

Task-number: QTBUG-6688
Reviewed-by: axis

1 files changed, 13 insertions, 2 deletions

diff --git a/tests/benchmarks/events/main.cpp b/tests/benchmarks/events/main.cpp
index 7c9de8f..09d6c53 100644
--- a/tests/benchmarks/events/main.cpp
+++ b/tests/benchmarks/events/main.cpp
@@ -47,6 +47,7 @@ class PingPong : public QObject
 {
 public:
     void setPeer(QObject *peer);
+    void resetCounter() {m_counter = 100;}
 
 protected:
     bool event(QEvent *e);
@@ -69,7 +70,7 @@ bool PingPong::event(QEvent *)
         QEvent *e = new QEvent(QEvent::User);
         QCoreApplication::postEvent(m_peer, e);
     } else {
-        QCoreApplication::quit();
+        QTestEventLoop::instance().exitLoop();
     }
     return true;
 }
@@ -149,6 +150,10 @@ void EventsBench::sendEvent()
 void EventsBench::postEvent_data()
 {
     QTest::addColumn<bool>("filterEvents");
+    // The first time an eventloop is executed, the case runs radically slower at least
+    // on some platforms, so test the "no eventfilter" case to get a comparable results
+    // with the "eventfilter" case.
+    QTest::newRow("first time, no eventfilter") << false;
     QTest::newRow("no eventfilter") << false;
     QTest::newRow("eventfilter") << true;
 }
@@ -164,8 +169,14 @@ void EventsBench::postEvent()
         ping.installEventFilter(this);
         pong.installEventFilter(this);
     }
-    QEvent *e = new QEvent(QEvent::User);
+
     QBENCHMARK {
+        // In case multiple iterations are done, event needs to be created inside the QBENCHMARK,
+        // or it gets deleted once first iteration exits and can cause a crash. Similarly,
+        // ping and pong need their counters reset.
+        QEvent *e = new QEvent(QEvent::User);
+        ping.resetCounter();
+        pong.resetCounter();
         QCoreApplication::postEvent(&ping, e);
         QTestEventLoop::instance().enterLoop( 61 );
     }