fix conditional glXSwapInterval usage

and cleanup profiling relics

REVIEW: 105632
BUG: 303397
(cherry picked from commit 0babc455aea4f5099a4f829668160bda3ef68a28)

composite.cpp

@@ -392,8 +392,8 @@ void Workspace::timerEvent(QTimerEvent *te)
     } else
         QObject::timerEvent(te);
 }
+
 static bool s_pending = false;
-QElapsedTimer profiler;
 void Workspace::performCompositing()
 {
     if (!scene->overlayWindow()->isVisible())
@@ -408,7 +408,6 @@ void Workspace::performCompositing()
         // Otherwise the window would not be painted normally anyway.
         return;
     }
-    profiler.start();
     s_pending = pending;
     // create a list of all windows in the stacking order
     ToplevelList windows = xStackingOrder();

scene_opengl_glx.cpp

@@ -514,18 +514,19 @@ void SceneOpenGL::waitSync()
         // but this only leads to waiting for two frames??!?
         glXGetVideoSync(&sync);
         glXWaitVideoSync(2, (sync + 1) % 2, &sync);
-#endif
+#else
         glXWaitVideoSync(1, 0, &sync);
+#endif
 #if VSYNC_DEBUG
-        static int waitTime = 0, waitCounter = 0, crapCounter = 0;
+        static int waitTime = 0, waitCounter = 0, doubleSyncCounter = 0;
         if (m_renderTimer.elapsed() > 11)
-            ++crapCounter;
+            ++doubleSyncCounter;
         waitTime += m_renderTimer.elapsed();
         ++waitCounter;
         if (waitCounter > 99)
         {
-            qDebug() << "mean vsync wait time:" << float((float)waitTime / (float)waitCounter) << crapCounter << "/100";
-            crapCounter = waitTime = waitCounter = 0;
+            qDebug() << "mean vsync wait time:" << float((float)waitTime / (float)waitCounter) << doubleSyncCounter << "/100";
+            doubleSyncCounter = waitTime = waitCounter = 0;
         }
 #endif
     }
@@ -590,7 +591,7 @@ void SceneOpenGL::flushBuffer(int mask, QRegion damage)
             }
         } else {
             if (glXSwapInterval) {
-                glXSwapInterval(1);
+                glXSwapInterval(options->isGlVSync() ? 1 : 0);
                 glXSwapBuffers(display(), glxbuffer);
                 glXSwapInterval(0);
                 m_renderTimer.start(); // this is important so we don't assume to be loosing frames in the compositor timing calculation