Dmitry Osipenko <[email protected]> writes:
> On 3/4/26 11:49, Alex Bennée wrote:
>> Dmitry Osipenko <[email protected]> writes:
>>
>>> From: Pierre-Eric Pelloux-Prayer <[email protected]>
>>>
>>> If EGL is used, we can rely on dmabuf to import textures without
>>> doing copies.
>>>
>>> To get this working on X11, we use the existing SDL hint:
>>> SDL_HINT_VIDEO_X11_FORCE_EGL (because dmabuf can't be used with GLX).
>>>
>>> Reviewed-by: Akihiko Odaki <[email protected]>
>>> Acked-by: Michael S. Tsirkin <[email protected]>
>>> Tested-by: Alex Bennée <[email protected]>
>>> Signed-off-by: Pierre-Eric Pelloux-Prayer
>>> <[email protected]>
>>> Reviewed-by: Yiwei Zhang <[email protected]>
>>> Signed-off-by: Dmitry Osipenko <[email protected]>
>>> ---
>>> include/ui/sdl2.h | 7 +++++
>>> meson.build | 6 ++---
>>> ui/sdl2-gl.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++
>>> ui/sdl2.c | 42 ++++++++++++++++++++++++++++++
>>> 4 files changed, 117 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/include/ui/sdl2.h b/include/ui/sdl2.h
>>> index dbe6e3d9739b..9daf5ecffae7 100644
>>> --- a/include/ui/sdl2.h
>>> +++ b/include/ui/sdl2.h
>>> @@ -45,6 +45,7 @@ struct sdl2_console {
>>> bool gui_keysym;
>>> SDL_GLContext winctx;
>>> QKbdState *kbd;
>>> + bool has_dmabuf;
>>> #ifdef CONFIG_OPENGL
>>> QemuGLShader *gls;
>>> egl_fb guest_fb;
>>> @@ -96,5 +97,11 @@ void sdl2_gl_scanout_texture(DisplayChangeListener *dcl,
>>> void *d3d_tex2d);
>>> void sdl2_gl_scanout_flush(DisplayChangeListener *dcl,
>>> uint32_t x, uint32_t y, uint32_t w, uint32_t h);
>>> +void sdl2_gl_scanout_dmabuf(DisplayChangeListener *dcl,
>>> + QemuDmaBuf *dmabuf);
>>> +void sdl2_gl_release_dmabuf(DisplayChangeListener *dcl,
>>> + QemuDmaBuf *dmabuf);
>>> +bool sdl2_gl_has_dmabuf(DisplayChangeListener *dcl);
>>> +void sdl2_gl_console_init(struct sdl2_console *scon);
>>>
>>> #endif /* SDL2_H */
>>> diff --git a/meson.build b/meson.build
>>> index 3cd1d8dbc669..0ce84d45e6f3 100644
>>> --- a/meson.build
>>> +++ b/meson.build
>>> @@ -1937,10 +1937,8 @@ if get_option('gtk') \
>>> endif
>>> endif
>>>
>>> -x11 = not_found
>>> -if gtkx11.found()
>>> - x11 = dependency('x11', method: 'pkg-config', required: gtkx11.found())
>>> -endif
>>> +x11 = dependency('x11', method: 'pkg-config', required: gtkx11.found())
>>> +
>>> png = not_found
>>> if get_option('png').allowed() and have_system
>>> png = dependency('libpng', version: '>=1.6.34', required:
>>> get_option('png'),
>>> diff --git a/ui/sdl2-gl.c b/ui/sdl2-gl.c
>>> index fbac3edbc09d..697ba2169c34 100644
>>> --- a/ui/sdl2-gl.c
>>> +++ b/ui/sdl2-gl.c
>>> @@ -26,6 +26,8 @@
>>> */
>>>
>>> #include "qemu/osdep.h"
>>> +#include "qemu/main-loop.h"
>>> +#include "qemu/error-report.h"
>>> #include "ui/console.h"
>>> #include "ui/input.h"
>>> #include "ui/sdl2.h"
>>> @@ -250,3 +252,67 @@ void sdl2_gl_scanout_flush(DisplayChangeListener *dcl,
>>>
>>> SDL_GL_SwapWindow(scon->real_window);
>>> }
>>> +
>>> +void sdl2_gl_scanout_dmabuf(DisplayChangeListener *dcl,
>>> + QemuDmaBuf *dmabuf)
>>> +{
>>> + struct sdl2_console *scon = container_of(dcl, struct sdl2_console,
>>> dcl);
>>> + const int *fds;
>>> +
>>> + assert(scon->opengl);
>>> + SDL_GL_MakeCurrent(scon->real_window, scon->winctx);
>>> +
>>> + egl_dmabuf_import_texture(dmabuf);
>>> + if (!qemu_dmabuf_get_texture(dmabuf)) {
>>> + fds = qemu_dmabuf_get_fds(dmabuf, NULL);
>>> + error_report("%s: failed fd=%d", __func__, fds ? fds[0] : -1);
>>> + return;
>>> + }
>>> +
>>> + sdl2_gl_scanout_texture(dcl, qemu_dmabuf_get_texture(dmabuf), false,
>>> + qemu_dmabuf_get_width(dmabuf),
>>> + qemu_dmabuf_get_height(dmabuf),
>>> + 0, 0,
>>> + qemu_dmabuf_get_width(dmabuf),
>>> + qemu_dmabuf_get_height(dmabuf),
>>> + NULL);
>>> +
>>> + if (qemu_dmabuf_get_allow_fences(dmabuf)) {
>>> + scon->guest_fb.dmabuf = dmabuf;
>>> + }
>>> +}
>>> +
>>> +void sdl2_gl_release_dmabuf(DisplayChangeListener *dcl,
>>> + QemuDmaBuf *dmabuf)
>>> +{
>>> + egl_dmabuf_release_texture(dmabuf);
>>> +}
>>> +
>>> +bool sdl2_gl_has_dmabuf(DisplayChangeListener *dcl)
>>> +{
>>> + struct sdl2_console *scon = container_of(dcl, struct sdl2_console,
>>> dcl);
>>> +
>>> + return scon->has_dmabuf;
>>> +}
>>> +
>>> +void sdl2_gl_console_init(struct sdl2_console *scon)
>>> +{
>>> + bool hidden = scon->hidden;
>>> +
>>> + scon->hidden = true;
>>> + scon->surface = qemu_create_displaysurface(1, 1);
>>> + sdl2_window_create(scon);
>>> +
>>> + /*
>>> + * QEMU checks whether console supports dma-buf before switching
>>> + * to the console. To break this chicken-egg problem we pre-check
>>> + * dma-buf availability beforehand using a dummy SDL window.
>>> + */
>>> + scon->has_dmabuf = qemu_egl_has_dmabuf();
>>> +
>>> + sdl2_window_destroy(scon);
>>> + qemu_free_displaysurface(scon->surface);
>>> +
>>> + scon->surface = NULL;
>>> + scon->hidden = hidden;
>>> +}
>>> diff --git a/ui/sdl2.c b/ui/sdl2.c
>>> index 032dc14bc398..3bb2676f847b 100644
>>> --- a/ui/sdl2.c
>>> +++ b/ui/sdl2.c
>>> @@ -35,6 +35,10 @@
>>> #include "qemu/log.h"
>>> #include "qemu-main.h"
>>>
>>> +#ifdef CONFIG_X11
>>> +#include <X11/Xlib.h>
>>> +#endif
>>> +
>>> static int sdl2_num_outputs;
>>> static struct sdl2_console *sdl2_console;
>>>
>>> @@ -120,6 +124,9 @@ void sdl2_window_create(struct sdl2_console *scon)
>>> /* The SDL renderer is only used by sdl2-2D, when OpenGL is
>>> disabled */
>>> scon->real_renderer = SDL_CreateRenderer(scon->real_window, -1, 0);
>>> }
>>> +
>>> + qemu_egl_display = eglGetCurrentDisplay();
>>> +
>>
>> This fails on MacOS for some reason:
>>
>> o libsystem.a.p/ui_sdl2.c.o -c ../ui/sdl2.c
>> ../ui/sdl2.c:128:5: error: use of undeclared identifier 'qemu_egl_display'
>> 128 | qemu_egl_display = eglGetCurrentDisplay();
>> | ^
>> ../ui/sdl2.c:128:24: error: call to undeclared function
>> 'eglGetCurrentDisplay'; ISO C99 and later do not support implicit
>> function declarations [-Wimplicit-function-declaration]
>> 128 | qemu_egl_display = eglGetCurrentDisplay();
>> | ^
>> 2 errors generated.
>>
>> See: https://gitlab.com/stsquad/qemu/-/jobs/13340079105
>>
>> Not sure what the include differences are because --enable-sdl builds
>> fine on Linux.
>
> Please try with this change and let me know if you could squash it or I
> need to send a patch:
>
> diff --git a/ui/sdl2.c b/ui/sdl2.c
> index 3bb2676f847b..2603b0c2bdd8 100644
> --- a/ui/sdl2.c
> +++ b/ui/sdl2.c
> @@ -125,7 +125,9 @@ void sdl2_window_create(struct sdl2_console *scon)
> scon->real_renderer = SDL_CreateRenderer(scon->real_window, -1, 0);
> }
>
> +#ifdef CONFIG_OPENGL
> qemu_egl_display = eglGetCurrentDisplay();
> +#endif
>
> sdl_update_caption(scon);
> }
There is one remaining build failure for win64:
../ui/sdl2-gl.c: In function 'sdl2_gl_scanout_dmabuf':
../ui/sdl2-gl.c:265:5: error: implicit declaration of function
'egl_dmabuf_import_texture'; did you mean 'qemu_dmabuf_set_texture'?
[-Wimplicit-function-declaration]
265 | egl_dmabuf_import_texture(dmabuf);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
| qemu_dmabuf_set_texture
../ui/sdl2-gl.c:265:5: error: nested extern declaration of
'egl_dmabuf_import_texture' [-Werror=nested-externs]
../ui/sdl2-gl.c: In function 'sdl2_gl_release_dmabuf':
../ui/sdl2-gl.c:288:5: error: implicit declaration of function
'egl_dmabuf_release_texture'; did you mean 'qemu_dmabuf_set_texture'?
[-Wimplicit-function-declaration]
288 | egl_dmabuf_release_texture(dmabuf);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
| qemu_dmabuf_set_texture
../ui/sdl2-gl.c:288:5: error: nested extern declaration of
'egl_dmabuf_release_texture' [-Werror=nested-externs]
cc1: all warnings being treated as errors
See: https://gitlab.com/stsquad/qemu/-/jobs/13340078806
--
Alex Bennée
Virtualisation Tech Lead @ Linaro
