6708580: Java applications slow when EXA enabled

Reviewed-by: prr, tdv
Contributed-by: Nceisserer <linuxhippy@gmail.com>

make/sun/awt/mapfile-mawt-vers

@@ -407,6 +407,7 @@ SUNWprivate_1.1 {
 		Java_sun_java2d_x11_X11SurfaceData_initSurface;
 		Java_sun_java2d_x11_X11SurfaceData_isDrawableValid;
 		Java_sun_java2d_x11_X11SurfaceData_isDgaAvailable;
+		Java_sun_java2d_x11_X11SurfaceData_isShmPMAvailable;
 		Java_sun_java2d_x11_X11SurfaceData_setInvalid;
 		Java_sun_java2d_x11_X11SurfaceData_flushNativeSurface;
                 Java_sun_java2d_x11_X11SurfaceData_XCreateGC;

make/sun/xawt/mapfile-vers

@@ -337,6 +337,7 @@ SUNWprivate_1.1 {
         Java_sun_java2d_x11_X11SurfaceData_initIDs;
 	Java_sun_java2d_x11_X11SurfaceData_isDrawableValid;
         Java_sun_java2d_x11_X11SurfaceData_isDgaAvailable;
+	Java_sun_java2d_x11_X11SurfaceData_isShmPMAvailable;
         Java_sun_java2d_x11_X11SurfaceData_initOps;
         Java_sun_java2d_x11_X11SurfaceData_initSurface;
         Java_sun_java2d_x11_X11SurfaceData_flushNativeSurface;

src/solaris/classes/sun/java2d/x11/X11SurfaceData.java

@@ -50,6 +50,7 @@ import sun.awt.image.PixelConverter;
 import sun.font.X11TextRenderer;
 import sun.java2d.InvalidPipeException;
 import sun.java2d.SunGraphics2D;
+import sun.java2d.SunGraphicsEnvironment;
 import sun.java2d.SurfaceData;
 import sun.java2d.SurfaceDataProxy;
 import sun.java2d.loops.SurfaceType;
@@ -240,6 +241,11 @@ public abstract class X11SurfaceData extends SurfaceData {
      */
     public static native boolean isDgaAvailable();
 
+    /**
+     * Returns true if shared memory pixmaps are available
+     */
+    private static native boolean isShmPMAvailable();
+
     public static boolean isAccelerationEnabled() {
         if (accelerationEnabled == null) {
 
@@ -253,8 +259,17 @@ public abstract class X11SurfaceData extends SurfaceData {
                     // true iff prop==true, false otherwise
                     accelerationEnabled = Boolean.valueOf(prop);
                 } else {
-                    // use pixmaps if there is no dga, no matter local or remote
-                    accelerationEnabled = Boolean.valueOf(!isDgaAvailable());
+                    boolean isDisplayLocal = false;
+                    GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
+                    if (ge instanceof SunGraphicsEnvironment) {
+                        isDisplayLocal = ((SunGraphicsEnvironment) ge).isDisplayLocal();
+                     }
+
+                    // EXA based drivers tend to place pixmaps in VRAM, slowing down readbacks.
+                    // Don't use pixmaps if dga is available,
+                    // or we are local and shared memory Pixmaps are not available.
+                    accelerationEnabled =
+                        !(isDgaAvailable() || (isDisplayLocal && !isShmPMAvailable()));
                 }
             }
         }

src/solaris/native/sun/java2d/x11/X11SurfaceData.c

@@ -208,6 +208,23 @@ Java_sun_java2d_x11_X11SurfaceData_isDgaAvailable(JNIEnv *env, jobject this)
 #endif /* HEADLESS */
 }
 
+
+/*
+ * Class:     sun_java2d_x11_X11SurfaceData
+ * Method:    isShmPMAvailable
+ * Signature: ()Z
+ */
+JNIEXPORT jboolean JNICALL
+Java_sun_java2d_x11_X11SurfaceData_isShmPMAvailable(JNIEnv *env, jobject this)
+{
+#if defined(HEADLESS) || !defined(MITSHM)
+    return JNI_FALSE;
+#else
+    return useMitShmPixmaps;
+#endif /* HEADLESS, MITSHM */
+}
+
+
 /*
  * Class:     sun_java2d_x11_X11SurfaceData
  * Method:    initOps