[PATCH v2 4/4] ui/console: Remove dpy_cursor_define_supported()

Akihiko Odaki posted 4 patches 5 months ago
Maintainers: "Michael S. Tsirkin" <mst@redhat.com>, Dmitry Fleytman <dmitry.fleytman@gmail.com>, "Marc-André Lureau" <marcandre.lureau@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, "Daniel P. Berrangé" <berrange@redhat.com>, Thomas Huth <thuth@redhat.com>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Peter Maydell <peter.maydell@linaro.org>, Akihiko Odaki <akihiko.odaki@daynix.com>
[PATCH v2 4/4] ui/console: Remove dpy_cursor_define_supported()
Posted by Akihiko Odaki 5 months ago
Remove dpy_cursor_define_supported() as it brings no benefit today and
it has a few inherent problems.

All graphical displays except egl-headless support cursor composition
without DMA-BUF, and egl-headless is meant to be used in conjunction
with another graphical display, so dpy_cursor_define_supported()
always returns true and meaningless.

Even if we add a new display without cursor composition in the future,
dpy_cursor_define_supported() will be problematic as a cursor display
fix for it because some display devices like virtio-gpu cannot tell the
lack of cursor composition capability to the guest and are unable to
utilize the value the function returns. Therefore, all non-headless
graphical displays must actually implement cursor composition for
correct cursor display.

Another problem with dpy_cursor_define_supported() is that it returns
true even if only some of the display listeners support cursor
composition, which is wrong unless all display listeners that lack
cursor composition is headless.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
---
 include/ui/console.h    |  1 -
 hw/display/qxl-render.c |  4 ----
 hw/display/vmware_vga.c |  6 ++----
 ui/console.c            | 13 -------------
 4 files changed, 2 insertions(+), 22 deletions(-)

diff --git a/include/ui/console.h b/include/ui/console.h
index 82b573e68082..fa986ab97e3b 100644
--- a/include/ui/console.h
+++ b/include/ui/console.h
@@ -324,7 +324,6 @@ void dpy_text_update(QemuConsole *con, int x, int y, int w, int h);
 void dpy_text_resize(QemuConsole *con, int w, int h);
 void dpy_mouse_set(QemuConsole *con, int x, int y, bool on);
 void dpy_cursor_define(QemuConsole *con, QEMUCursor *cursor);
-bool dpy_cursor_define_supported(QemuConsole *con);
 bool dpy_gfx_check_format(QemuConsole *con,
                           pixman_format_code_t format);
 
diff --git a/hw/display/qxl-render.c b/hw/display/qxl-render.c
index ec99ec887a6e..837d2446cd52 100644
--- a/hw/display/qxl-render.c
+++ b/hw/display/qxl-render.c
@@ -307,10 +307,6 @@ int qxl_render_cursor(PCIQXLDevice *qxl, QXLCommandExt *ext)
         return 1;
     }
 
-    if (!dpy_cursor_define_supported(qxl->vga.con)) {
-        return 0;
-    }
-
     if (qxl->debug > 1 && cmd->type != QXL_CURSOR_MOVE) {
         fprintf(stderr, "%s", __func__);
         qxl_log_cmd_cursor(qxl, cmd, ext->group_id);
diff --git a/hw/display/vmware_vga.c b/hw/display/vmware_vga.c
index 512f224b9f58..3db3ff98f763 100644
--- a/hw/display/vmware_vga.c
+++ b/hw/display/vmware_vga.c
@@ -904,10 +904,8 @@ static uint32_t vmsvga_value_read(void *opaque, uint32_t address)
         caps |= SVGA_CAP_RECT_FILL;
 #endif
 #ifdef HW_MOUSE_ACCEL
-        if (dpy_cursor_define_supported(s->vga.con)) {
-            caps |= SVGA_CAP_CURSOR | SVGA_CAP_CURSOR_BYPASS_2 |
-                    SVGA_CAP_CURSOR_BYPASS;
-        }
+        caps |= SVGA_CAP_CURSOR | SVGA_CAP_CURSOR_BYPASS_2 |
+                SVGA_CAP_CURSOR_BYPASS;
 #endif
         ret = caps;
         break;
diff --git a/ui/console.c b/ui/console.c
index 0ec70cb50ce6..33976446425e 100644
--- a/ui/console.c
+++ b/ui/console.c
@@ -1001,19 +1001,6 @@ void dpy_cursor_define(QemuConsole *c, QEMUCursor *cursor)
     }
 }
 
-bool dpy_cursor_define_supported(QemuConsole *con)
-{
-    DisplayState *s = con->ds;
-    DisplayChangeListener *dcl;
-
-    QLIST_FOREACH(dcl, &s->listeners, next) {
-        if (dcl->ops->dpy_cursor_define) {
-            return true;
-        }
-    }
-    return false;
-}
-
 QEMUGLContext dpy_gl_ctx_create(QemuConsole *con,
                                 struct QEMUGLParams *qparams)
 {

-- 
2.45.2
Re: [PATCH v2 4/4] ui/console: Remove dpy_cursor_define_supported()
Posted by Marc-André Lureau 4 months, 4 weeks ago
On Thu, Jun 27, 2024 at 3:19 PM Akihiko Odaki <akihiko.odaki@daynix.com>
wrote:

> Remove dpy_cursor_define_supported() as it brings no benefit today and
> it has a few inherent problems.
>
> All graphical displays except egl-headless support cursor composition
> without DMA-BUF, and egl-headless is meant to be used in conjunction
> with another graphical display, so dpy_cursor_define_supported()
> always returns true and meaningless.
>
> Even if we add a new display without cursor composition in the future,
> dpy_cursor_define_supported() will be problematic as a cursor display
> fix for it because some display devices like virtio-gpu cannot tell the
> lack of cursor composition capability to the guest and are unable to
> utilize the value the function returns. Therefore, all non-headless
> graphical displays must actually implement cursor composition for
> correct cursor display.
>
> Another problem with dpy_cursor_define_supported() is that it returns
> true even if only some of the display listeners support cursor
> composition, which is wrong unless all display listeners that lack
> cursor composition is headless.
>
> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
>

Agreed,
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>

> ---
>  include/ui/console.h    |  1 -
>  hw/display/qxl-render.c |  4 ----
>  hw/display/vmware_vga.c |  6 ++----
>  ui/console.c            | 13 -------------
>  4 files changed, 2 insertions(+), 22 deletions(-)
>
> diff --git a/include/ui/console.h b/include/ui/console.h
> index 82b573e68082..fa986ab97e3b 100644
> --- a/include/ui/console.h
> +++ b/include/ui/console.h
> @@ -324,7 +324,6 @@ void dpy_text_update(QemuConsole *con, int x, int y,
> int w, int h);
>  void dpy_text_resize(QemuConsole *con, int w, int h);
>  void dpy_mouse_set(QemuConsole *con, int x, int y, bool on);
>  void dpy_cursor_define(QemuConsole *con, QEMUCursor *cursor);
> -bool dpy_cursor_define_supported(QemuConsole *con);
>  bool dpy_gfx_check_format(QemuConsole *con,
>                            pixman_format_code_t format);
>
> diff --git a/hw/display/qxl-render.c b/hw/display/qxl-render.c
> index ec99ec887a6e..837d2446cd52 100644
> --- a/hw/display/qxl-render.c
> +++ b/hw/display/qxl-render.c
> @@ -307,10 +307,6 @@ int qxl_render_cursor(PCIQXLDevice *qxl,
> QXLCommandExt *ext)
>          return 1;
>      }
>
> -    if (!dpy_cursor_define_supported(qxl->vga.con)) {
> -        return 0;
> -    }
> -
>      if (qxl->debug > 1 && cmd->type != QXL_CURSOR_MOVE) {
>          fprintf(stderr, "%s", __func__);
>          qxl_log_cmd_cursor(qxl, cmd, ext->group_id);
> diff --git a/hw/display/vmware_vga.c b/hw/display/vmware_vga.c
> index 512f224b9f58..3db3ff98f763 100644
> --- a/hw/display/vmware_vga.c
> +++ b/hw/display/vmware_vga.c
> @@ -904,10 +904,8 @@ static uint32_t vmsvga_value_read(void *opaque,
> uint32_t address)
>          caps |= SVGA_CAP_RECT_FILL;
>  #endif
>  #ifdef HW_MOUSE_ACCEL
> -        if (dpy_cursor_define_supported(s->vga.con)) {
> -            caps |= SVGA_CAP_CURSOR | SVGA_CAP_CURSOR_BYPASS_2 |
> -                    SVGA_CAP_CURSOR_BYPASS;
> -        }
> +        caps |= SVGA_CAP_CURSOR | SVGA_CAP_CURSOR_BYPASS_2 |
> +                SVGA_CAP_CURSOR_BYPASS;
>  #endif
>          ret = caps;
>          break;
> diff --git a/ui/console.c b/ui/console.c
> index 0ec70cb50ce6..33976446425e 100644
> --- a/ui/console.c
> +++ b/ui/console.c
> @@ -1001,19 +1001,6 @@ void dpy_cursor_define(QemuConsole *c, QEMUCursor
> *cursor)
>      }
>  }
>
> -bool dpy_cursor_define_supported(QemuConsole *con)
> -{
> -    DisplayState *s = con->ds;
> -    DisplayChangeListener *dcl;
> -
> -    QLIST_FOREACH(dcl, &s->listeners, next) {
> -        if (dcl->ops->dpy_cursor_define) {
> -            return true;
> -        }
> -    }
> -    return false;
> -}
> -
>  QEMUGLContext dpy_gl_ctx_create(QemuConsole *con,
>                                  struct QEMUGLParams *qparams)
>  {
>
> --
> 2.45.2
>
>
>

-- 
Marc-André Lureau
Re: [PATCH v2 4/4] ui/console: Remove dpy_cursor_define_supported()
Posted by Phil Dennis-Jordan 4 months, 3 weeks ago
On Sat, 29 Jun 2024 at 14:21, Marc-André Lureau <marcandre.lureau@gmail.com>
wrote:

>
>> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
>>
>
> Agreed,
> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
>

Reviewed-by: Phil Dennis-Jordan <phil@philjordan.eu>