[mutter] renderer-native: Don't attempt to queue mode sets on non-onscreen views

[Marge Bot <marge-bot src gnome org>]

commit 8478db96f9b8507cc025e16c52187bd86fb26b1d
Author: Jonas Ådahl <jadahl gmail com>
Date:   Wed Jun 9 18:28:46 2021 +0200

    renderer-native: Don't attempt to queue mode sets on non-onscreen views
    
    A view is only a 'CoglOnscreen' if it ends up on a CRTC, thus needs a
    mode. Other views are for virtual monitors, and require no mode setting,
    so exclude them from the pending mode set list.
    
    This avoids a dead lock when we'll be waiting indefinitely for mode
    setting on a virtual monitor.
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1891>

 src/backends/native/meta-renderer-native.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)
---
diff --git a/src/backends/native/meta-renderer-native.c b/src/backends/native/meta-renderer-native.c
index f12e2dda74..a84f3025f0 100644
--- a/src/backends/native/meta-renderer-native.c
+++ b/src/backends/native/meta-renderer-native.c
@@ -829,10 +829,22 @@ static void
 meta_renderer_native_queue_modes_reset (MetaRendererNative *renderer_native)
 {
   MetaRenderer *renderer = META_RENDERER (renderer_native);
+  GList *l;
 
   g_list_free (renderer_native->pending_mode_set_views);
-  renderer_native->pending_mode_set_views =
-    g_list_copy (meta_renderer_get_views (renderer));
+  for (l = meta_renderer_get_views (renderer); l; l = l->next)
+    {
+      ClutterStageView *stage_view = l->data;
+      CoglFramebuffer *framebuffer =
+        clutter_stage_view_get_onscreen (stage_view);
+
+      if (COGL_IS_ONSCREEN (framebuffer))
+        {
+          renderer_native->pending_mode_set_views =
+            g_list_prepend (renderer_native->pending_mode_set_views,
+                            stage_view);
+        }
+    }
   renderer_native->pending_mode_set = TRUE;
 
   meta_topic (META_DEBUG_KMS, "Queue mode set");