Re: [PATCH v2 16/18] ui: introduce egl_init()

["Daniel P. Berrangé" <berrange@redhat.com>]

On Tue, Mar 07, 2023 at 03:56:35PM +0400, marcandre.lureau@redhat.com wrote:
> From: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> Future patches will introduce EGL support on win32 (too late for 8.0
> though). Having a common place for EGL initialization and error handling
> will make it simpler.
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  include/ui/egl-helpers.h |  2 ++
>  ui/dbus.c                |  7 +------
>  ui/egl-headless.c        | 16 ++++++++--------
>  ui/egl-helpers.c         | 25 +++++++++++++++++++++++++
>  ui/spice-core.c          |  7 +------
>  5 files changed, 37 insertions(+), 20 deletions(-)
> 
> diff --git a/include/ui/egl-helpers.h b/include/ui/egl-helpers.h
> index c92dd90e33..53d953ddf4 100644
> --- a/include/ui/egl-helpers.h
> +++ b/include/ui/egl-helpers.h
> @@ -65,4 +65,6 @@ int qemu_egl_init_dpy_mesa(EGLNativeDisplayType dpy, DisplayGLMode mode);
>  EGLContext qemu_egl_init_ctx(void);
>  bool qemu_egl_has_dmabuf(void);
>  
> +bool egl_init(const char *rendernode, DisplayGLMode mode, Error **errp);
> +
>  #endif /* EGL_HELPERS_H */
> diff --git a/ui/dbus.c b/ui/dbus.c
> index f529928f0b..ebf03bd84d 100644
> --- a/ui/dbus.c
> +++ b/ui/dbus.c
> @@ -451,12 +451,7 @@ early_dbus_init(DisplayOptions *opts)
>      DisplayGLMode mode = opts->has_gl ? opts->gl : DISPLAYGL_MODE_OFF;
>  
>      if (mode != DISPLAYGL_MODE_OFF) {
> -        if (egl_rendernode_init(opts->u.dbus.rendernode, mode) < 0) {
> -            error_report("dbus: render node init failed");
> -            exit(1);
> -        }
> -
> -        display_opengl = 1;
> +        egl_init(opts->u.dbus.rendernode, mode, &error_fatal);
>      }
>  
>      type_register(&dbus_vc_type_info);
> diff --git a/ui/egl-headless.c b/ui/egl-headless.c
> index ae07e91302..ef70e6a18e 100644
> --- a/ui/egl-headless.c
> +++ b/ui/egl-headless.c
> @@ -1,7 +1,7 @@
>  #include "qemu/osdep.h"
>  #include "qemu/error-report.h"
>  #include "qemu/module.h"
> -#include "sysemu/sysemu.h"
> +#include "qapi/error.h"
>  #include "ui/console.h"
>  #include "ui/egl-helpers.h"
>  #include "ui/egl-context.h"
> @@ -191,21 +191,21 @@ static const DisplayGLCtxOps eglctx_ops = {
>  
>  static void early_egl_headless_init(DisplayOptions *opts)
>  {
> -    display_opengl = 1;
> +    DisplayGLMode mode = DISPLAYGL_MODE_ON;
> +
> +    if (opts->has_gl) {
> +        mode = opts->gl;
> +    }
> +
> +    egl_init(opts->u.egl_headless.rendernode, mode, &error_fatal);
>  }
>  
>  static void egl_headless_init(DisplayState *ds, DisplayOptions *opts)
>  {
> -    DisplayGLMode mode = opts->has_gl ? opts->gl : DISPLAYGL_MODE_ON;
>      QemuConsole *con;
>      egl_dpy *edpy;
>      int idx;
>  
> -    if (egl_rendernode_init(opts->u.egl_headless.rendernode, mode) < 0) {
> -        error_report("egl: render node init failed");
> -        exit(1);
> -    }
> -
>      for (idx = 0;; idx++) {
>          DisplayGLCtx *ctx;

Why isn't the egl_init() call being made from this egl_headless_init
method, so egl_rendernode_init() is called at the same logical point
as before this change ?


> diff --git a/ui/egl-helpers.c b/ui/egl-helpers.c
> index 10772b6471..36b4fc51d9 100644
> --- a/ui/egl-helpers.c
> +++ b/ui/egl-helpers.c
> @@ -19,6 +19,8 @@
>  #include "qemu/error-report.h"
>  #include "ui/console.h"
>  #include "ui/egl-helpers.h"
> +#include "sysemu/sysemu.h"
> +#include "qapi/error.h"
>  
>  EGLDisplay *qemu_egl_display;
>  EGLConfig qemu_egl_config;
> @@ -569,3 +571,26 @@ EGLContext qemu_egl_init_ctx(void)
>  
>      return ectx;
>  }
> +
> +bool egl_init(const char *rendernode, DisplayGLMode mode, Error **errp)
> +{
> +    ERRP_GUARD();
> +
> +    if (mode == DISPLAYGL_MODE_OFF) {
> +        error_setg(errp, "egl: turning off GL doesn't make sense");
> +        return false;
> +    }
> +
> +#ifdef CONFIG_GBM
> +    if (egl_rendernode_init(rendernode, mode) < 0) {
> +        error_setg(errp, "egl: render node init failed");
> +        return false;
> +    }
> +#else
> +    error_setg(errp, "egl: not available on this platform");
> +    return false;
> +#endif
> +
> +    display_opengl = 1;
> +    return true;
> +}

Surely this is going to result in compile errors when !CONFIG_GBM
because these two lines are going to be flagged as unreachable
code, due to the 'return false' in the #else branch.

> diff --git a/ui/spice-core.c b/ui/spice-core.c
> index 76f7c2bc3d..b05c830086 100644
> --- a/ui/spice-core.c
> +++ b/ui/spice-core.c
> @@ -820,12 +820,7 @@ static void qemu_spice_init(void)
>                           "incompatible with -spice port/tls-port");
>              exit(1);
>          }
> -        if (egl_rendernode_init(qemu_opt_get(opts, "rendernode"),
> -                                DISPLAYGL_MODE_ON) != 0) {
> -            error_report("Failed to initialize EGL render node for SPICE GL");
> -            exit(1);
> -        }
> -        display_opengl = 1;
> +        egl_init(qemu_opt_get(opts, "rendernode"), DISPLAYGL_MODE_ON, &error_fatal);
>          spice_opengl = 1;
>      }
>  #endif
> -- 
> 2.39.2
> 

With regards,
Daniel
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