Re: [PATCH 1/3] ui/gtk: skip drawing guest scanout when associated VC is invisible

[Marc-André Lureau]

Hi Dongwon

On Wed, Jan 31, 2024 at 3:50 AM <dongwon.kim@intel.com> wrote:
>
> From: Dongwon Kim <dongwon.kim@intel.com>
>
> A new flag "visible" is added to show visibility status of the gfx console.
> The flag is set to 'true' when the VC is visible but set to 'false' when
> it is hidden or closed. When the VC is invisible, drawing guest frames
> should be skipped as it will never be completed and it would potentially
> lock up the guest display especially when blob scanout is used.

Can't it skip drawing when the widget is not visible instead?
https://docs.gtk.org/gtk3/method.Widget.is_visible.html

>
> Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
> Cc: Gerd Hoffmann <kraxel@redhat.com>
> Cc: Vivek Kasireddy <vivek.kasireddy@intel.com>
>
> Signed-off-by: Dongwon Kim <dongwon.kim@intel.com>
> ---
>  include/ui/gtk.h |  1 +
>  ui/gtk-egl.c     |  8 ++++++++
>  ui/gtk-gl-area.c |  8 ++++++++
>  ui/gtk.c         | 10 +++++++++-
>  4 files changed, 26 insertions(+), 1 deletion(-)
>
> diff --git a/include/ui/gtk.h b/include/ui/gtk.h
> index aa3d637029..2de38e5724 100644
> --- a/include/ui/gtk.h
> +++ b/include/ui/gtk.h
> @@ -57,6 +57,7 @@ typedef struct VirtualGfxConsole {
>      bool y0_top;
>      bool scanout_mode;
>      bool has_dmabuf;
> +    bool visible;
>  #endif
>  } VirtualGfxConsole;
>
> diff --git a/ui/gtk-egl.c b/ui/gtk-egl.c
> index 3af5ac5bcf..993c283191 100644
> --- a/ui/gtk-egl.c
> +++ b/ui/gtk-egl.c
> @@ -265,6 +265,10 @@ void gd_egl_scanout_dmabuf(DisplayChangeListener *dcl,
>  #ifdef CONFIG_GBM
>      VirtualConsole *vc = container_of(dcl, VirtualConsole, gfx.dcl);
>
> +    if (!vc->gfx.visible) {
> +        return;
> +    }
> +
>      eglMakeCurrent(qemu_egl_display, vc->gfx.esurface,
>                     vc->gfx.esurface, vc->gfx.ectx);
>
> @@ -363,6 +367,10 @@ void gd_egl_flush(DisplayChangeListener *dcl,
>      VirtualConsole *vc = container_of(dcl, VirtualConsole, gfx.dcl);
>      GtkWidget *area = vc->gfx.drawing_area;
>
> +    if (!vc->gfx.visible) {
> +        return;
> +    }
> +
>      if (vc->gfx.guest_fb.dmabuf && !vc->gfx.guest_fb.dmabuf->draw_submitted) 
> {
>          graphic_hw_gl_block(vc->gfx.dcl.con, true);
>          vc->gfx.guest_fb.dmabuf->draw_submitted = true;
> diff --git a/ui/gtk-gl-area.c b/ui/gtk-gl-area.c
> index 52dcac161e..04e07bd7ee 100644
> --- a/ui/gtk-gl-area.c
> +++ b/ui/gtk-gl-area.c
> @@ -285,6 +285,10 @@ void gd_gl_area_scanout_flush(DisplayChangeListener *dcl,
>  {
>      VirtualConsole *vc = container_of(dcl, VirtualConsole, gfx.dcl);
>
> +    if (!vc->gfx.visible) {
> +        return;
> +    }
> +
>      if (vc->gfx.guest_fb.dmabuf && !vc->gfx.guest_fb.dmabuf->draw_submitted) 
> {
>          graphic_hw_gl_block(vc->gfx.dcl.con, true);
>          vc->gfx.guest_fb.dmabuf->draw_submitted = true;
> @@ -299,6 +303,10 @@ void gd_gl_area_scanout_dmabuf(DisplayChangeListener 
> *dcl,
>  #ifdef CONFIG_GBM
>      VirtualConsole *vc = container_of(dcl, VirtualConsole, gfx.dcl);
>
> +    if (!vc->gfx.visible) {
> +        return;
> +    }
> +
>      gtk_gl_area_make_current(GTK_GL_AREA(vc->gfx.drawing_area));
>      egl_dmabuf_import_texture(dmabuf);
>      if (!dmabuf->texture) {
> diff --git a/ui/gtk.c b/ui/gtk.c
> index 810d7fc796..02eb667d8a 100644
> --- a/ui/gtk.c
> +++ b/ui/gtk.c
> @@ -1312,15 +1312,20 @@ static void gd_menu_quit(GtkMenuItem *item, void 
> *opaque)
>  static void gd_menu_switch_vc(GtkMenuItem *item, void *opaque)
>  {
>      GtkDisplayState *s = opaque;
> -    VirtualConsole *vc = gd_vc_find_by_menu(s);
> +    VirtualConsole *vc;
>      GtkNotebook *nb = GTK_NOTEBOOK(s->notebook);
>      gint page;
>
> +    vc = gd_vc_find_current(s);
> +    vc->gfx.visible = false;
> +
> +    vc = gd_vc_find_by_menu(s);
>      gtk_release_modifiers(s);
>      if (vc) {
>          page = gtk_notebook_page_num(nb, vc->tab_item);
>          gtk_notebook_set_current_page(nb, page);
>          gtk_widget_grab_focus(vc->focus);
> +        vc->gfx.visible = true;
>      }
>  }
>
> @@ -1350,6 +1355,7 @@ static gboolean gd_tab_window_close(GtkWidget *widget, 
> GdkEvent *event,
>      VirtualConsole *vc = opaque;
>      GtkDisplayState *s = vc->s;
>
> +    vc->gfx.visible = false;
>      gtk_widget_set_sensitive(vc->menu_item, true);
>      gd_widget_reparent(vc->window, s->notebook, vc->tab_item);
>      gtk_notebook_set_tab_label_text(GTK_NOTEBOOK(s->notebook),
> @@ -1423,6 +1429,7 @@ static void gd_menu_untabify(GtkMenuItem *item, void 
> *opaque)
>          gd_update_geometry_hints(vc);
>          gd_update_caption(s);
>      }
> +    vc->gfx.visible = true;
>  }
>
>  static void gd_menu_show_menubar(GtkMenuItem *item, void *opaque)
> @@ -2471,6 +2478,7 @@ static void gtk_display_init(DisplayState *ds, 
> DisplayOptions *opts)
>  #ifdef CONFIG_GTK_CLIPBOARD
>      gd_clipboard_init(s);
>  #endif /* CONFIG_GTK_CLIPBOARD */
> +    vc->gfx.visible = true;
>  }
>
>  static void early_gtk_display_init(DisplayOptions *opts)
> --
> 2.34.1
>
>


-- 
Marc-André Lureau