Miklós Máté <mtmkls@gmail.com> writes:

On 04/04/17 16:06, Alexandre Julliard wrote:

Miklós Máté <mtmkls@gmail.com> writes:

On 04/04/17 12:11, Alexandre Julliard wrote:

Miklós Máté <mtmkls@gmail.com> writes:

@@ -1334,21 +1334,21 @@ static void free_gl_drawable( struct gl_drawable *gl )
   /***********************************************************************
    *              create_gl_drawable
    */
-static BOOL create_gl_drawable( HWND hwnd, struct gl_drawable *gl )
+static BOOL create_gl_drawable( HWND hwnd, struct gl_drawable *gl, struct x11drv_win_data *data )
   {
       gl->drawable = 0;
         if (GetAncestor( hwnd, GA_PARENT ) == GetDesktopWindow())
/* top-level window */
       {
-        struct x11drv_win_data *data = get_win_data( hwnd );
-
           if (data)
           {
               gl->type = DC_GL_WINDOW;
               gl->window = create_client_window( data, gl->visual );
               if (gl->window)
+            {
                   gl->drawable = pglXCreateWindow( gdi_display, gl->format->fbconfig, gl->window, NULL );
-            release_win_data( data );
+                XSync( gdi_display, False );

Do you really need all the extra XSync calls?  We try to avoid server
round-trips as much as possible.

Yes. We must ensure that glXCreateWindow() and glXDestroyWindow()
refer to a valid X window, so the command queue of data->display and
gdi_display have to be in sync around those calls.

If the goal is that the X window is valid, I'd have expected an XSync on
the thread display. Why is the XSync on gdi_display needed here? What is
the scenario that fails?

I'm not questioning that some XSyncs are necessary (and we already have
a few), but I want to make sure we don't add more than needed.

This one prevents crash in the following scenario:

1. create_gl_drawable()

2. X11DRV_ThreadDetach() calls XCloseDisplay( data->display );

3. the Xserver processes the glXCreateWindow in the command queue of
gdi_display -> X window is not valid

This happens sometimes during the ddraw and d3d9 tests.

Shouldn't this be happening even without your other changes then?

Well, according to my notes from half a year ago the ddraw test of wine-csmt definitely crashes without this, but now I can't reproduce it. I don't know how likely the above scenario is in the real world.

MM