egl: refactor EGL extensions initialization

Store the looked up functions pointers with the struct virgl_egl, to
avoid extra lookups later on. Extensions are checked iteratively (before
and after the EGL display is created). The associated functions pointers
are loaded according to the extension presence implicitly in
virgl_egl_add_extensions().

The required extensions check is moved from virgl_egl_init_extensions()
to virgl_egl_check_extensions().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gert Wollny <gert.wollny@collabora.com>
Part-of: <https://gitlab.freedesktop.org/virgl/virglrenderer/-/merge_requests/1103>

1 files changed, 80 insertions, 64 deletions

diff --git a/src/vrend_winsys_egl.c b/src/vrend_winsys_egl.c
index ce68f36..0a9271f 100644
--- a/src/vrend_winsys_egl.c
+++ b/src/vrend_winsys_egl.c
@@ -63,6 +63,9 @@
 #define EGL_EXT_IMAGE_DMA_BUF_IMPORT           BIT(6)
 #define EGL_EXT_IMAGE_DMA_BUF_IMPORT_MODIFIERS BIT(7)
 #define EGL_KHR_FENCE_SYNC_ANDROID             BIT(8)
+#define EGL_EXT_PLATFORM_BASE                  BIT(9)
+#define EGL_EXT_DEVICE_ENUMERATION             BIT(10)
+#define EGL_EXT_DEVICE_QUERY                   BIT(11)
 
 static const struct {
    uint32_t bit;
@@ -75,7 +78,16 @@ static const struct {
    { EGL_KHR_GL_COLORSPACE, "EGL_KHR_gl_colorspace" },
    { EGL_EXT_IMAGE_DMA_BUF_IMPORT, "EGL_EXT_image_dma_buf_import" },
    { EGL_EXT_IMAGE_DMA_BUF_IMPORT_MODIFIERS, "EGL_EXT_image_dma_buf_import_modifiers" },
-   { EGL_KHR_FENCE_SYNC_ANDROID, "EGL_ANDROID_native_fence_sync"}
+   { EGL_KHR_FENCE_SYNC_ANDROID, "EGL_ANDROID_native_fence_sync"},
+   { EGL_EXT_PLATFORM_BASE, "EGL_EXT_platform_base" },
+   { EGL_EXT_DEVICE_ENUMERATION, "EGL_EXT_device_enumeration" },
+   { EGL_EXT_DEVICE_QUERY, "EGL_EXT_device_query" },
+};
+
+struct egl_funcs {
+   PFNEGLGETPLATFORMDISPLAYEXTPROC eglGetPlatformDisplay;
+   PFNEGLQUERYDEVICESEXTPROC eglQueryDevices;
+   PFNEGLQUERYDEVICESTRINGEXTPROC eglQueryDeviceString;
 };
 
 struct virgl_egl {
@@ -88,6 +100,7 @@ struct virgl_egl {
    uint32_t extension_bits;
    EGLSyncKHR signaled_fence;
    bool different_gpu;
+   struct egl_funcs funcs;
 };
 
 static bool virgl_egl_has_extension_in_string(const char *haystack, const char *needle)
@@ -122,63 +135,54 @@ static bool virgl_egl_has_extension_in_string(const char *haystack, const char *
    return false;
 }
 
-static int virgl_egl_init_extensions(struct virgl_egl *egl, const char *extensions)
+static bool virgl_egl_get_funcs(struct virgl_egl *egl)
 {
-   for (uint32_t i = 0; i < ARRAY_SIZE(extensions_list); i++) {
-      if (virgl_egl_has_extension_in_string(extensions, extensions_list[i].string))
-         egl->extension_bits |= extensions_list[i].bit;
-   }
+   assert(egl);
 
-   if (!has_bits(egl->extension_bits, EGL_KHR_SURFACELESS_CONTEXT | EGL_KHR_CREATE_CONTEXT)) {
-      vrend_printf( "Missing EGL_KHR_surfaceless_context or EGL_KHR_create_context\n");
-      return -1;
+   if (has_bit(egl->extension_bits, EGL_EXT_PLATFORM_BASE)) {
+      egl->funcs.eglGetPlatformDisplay =
+         (PFNEGLGETPLATFORMDISPLAYEXTPROC) eglGetProcAddress("eglGetPlatformDisplayEXT");
+      if (!egl->funcs.eglGetPlatformDisplay)
+         return false;
    }
 
-   return 0;
-}
+   if (has_bit(egl->extension_bits, EGL_EXT_DEVICE_QUERY)) {
+      egl->funcs.eglQueryDeviceString = (PFNEGLQUERYDEVICESTRINGEXTPROC)eglGetProcAddress("eglQueryDeviceStringEXT");
+      if (!egl->funcs.eglQueryDeviceString)
+         return false;
+   }
 
-#ifdef ENABLE_MINIGBM_ALLOCATION
+   if (has_bit(egl->extension_bits, EGL_EXT_DEVICE_ENUMERATION)) {
+      egl->funcs.eglQueryDevices = (PFNEGLQUERYDEVICESEXTPROC)eglGetProcAddress ("eglQueryDevicesEXT");
+      if (!egl->funcs.eglQueryDevices)
+         return false;
+   }
 
-struct egl_funcs {
-   PFNEGLGETPLATFORMDISPLAYEXTPROC eglGetPlatformDisplay;
-   PFNEGLQUERYDEVICESEXTPROC eglQueryDevices;
-   PFNEGLQUERYDEVICESTRINGEXTPROC eglQueryDeviceString;
-};
+   return true;
+}
 
-static bool virgl_egl_get_interface(struct egl_funcs *funcs)
+static bool virgl_egl_add_extensions(struct virgl_egl *egl, const char *extensions)
 {
-   const char *client_extensions = eglQueryString (NULL, EGL_EXTENSIONS);
-
-   assert(funcs);
-
-   if (virgl_egl_has_extension_in_string(client_extensions, "EGL_EXT_platform_base")) {
-      funcs->eglGetPlatformDisplay =
-         (PFNEGLGETPLATFORMDISPLAYEXTPROC) eglGetProcAddress ("eglGetPlatformDisplayEXT");
+   for (uint32_t i = 0; i < ARRAY_SIZE(extensions_list); i++) {
+      if (virgl_egl_has_extension_in_string(extensions, extensions_list[i].string))
+         egl->extension_bits |= extensions_list[i].bit;
    }
 
-   if (!funcs->eglGetPlatformDisplay)
-      return false;
-
-   if (!virgl_egl_has_extension_in_string(client_extensions, "EGL_EXT_platform_device"))
-      return false;
-
-   if (!virgl_egl_has_extension_in_string(client_extensions, "EGL_EXT_device_enumeration"))
-      return false;
-
-   funcs->eglQueryDevices = (PFNEGLQUERYDEVICESEXTPROC)eglGetProcAddress ("eglQueryDevicesEXT");
-   if (!funcs->eglQueryDevices)
-      return false;
-
-   if (!virgl_egl_has_extension_in_string(client_extensions, "EGL_EXT_device_query"))
-      return false;
+   return virgl_egl_get_funcs(egl);
+}
 
-   funcs->eglQueryDeviceString = (PFNEGLQUERYDEVICESTRINGEXTPROC)eglGetProcAddress("eglQueryDeviceStringEXT");
-   if (!funcs->eglQueryDeviceString)
+static bool virgl_egl_check_extensions(struct virgl_egl *egl)
+{
+   if (!has_bits(egl->extension_bits, EGL_KHR_SURFACELESS_CONTEXT | EGL_KHR_CREATE_CONTEXT)) {
+      vrend_printf( "Missing EGL_KHR_surfaceless_context or EGL_KHR_create_context\n");
       return false;
+   }
 
-  return true;
+   return true;
 }
 
+#ifdef ENABLE_MINIGBM_ALLOCATION
+
 static EGLint virgl_egl_find_3d_device(struct gbm_device_info *dev_infos, EGLint num_devices, uint32_t flags)
 {
    EGLint d;
@@ -216,7 +220,7 @@ static EGLDeviceEXT virgl_egl_get_device(struct virgl_egl *egl, struct egl_funcs
    if (gbm_detect_device_info(0, gbm_device_get_fd(egl->gbm->device), &gbm_dev_info) < 0)
       return EGL_NO_DEVICE_EXT;
 
-   if (!funcs->eglQueryDevices(max_devices, devices, &num_devices))
+   if (!egl->funcs.eglQueryDevices(max_devices, devices, &num_devices))
       return EGL_NO_DEVICE_EXT;
 
    /* We query EGL_DRM_DEVICE_FILE_EXT without checking EGL_EXT_device_drm extension,
@@ -224,7 +228,7 @@ static EGLDeviceEXT virgl_egl_get_device(struct virgl_egl *egl, struct egl_funcs
     * after initializing display for every device.
     */
    for (d = 0; d < num_devices; d++) {
-       const char *dev_node = funcs->eglQueryDeviceString(devices[d], EGL_DRM_DEVICE_FILE_EXT);
+       const char *dev_node = egl->funcs.eglQueryDeviceString(devices[d], EGL_DRM_DEVICE_FILE_EXT);
        memset(&dev_infos[d], 0, sizeof(dev_infos[d]));
        if (dev_node) {
           if (gbm_detect_device_info_path(0, dev_node, dev_infos+d) < 0)
@@ -257,21 +261,24 @@ static EGLDeviceEXT virgl_egl_get_device(struct virgl_egl *egl, struct egl_funcs
 
 static bool virgl_egl_get_display(struct virgl_egl *egl)
 {
-   struct egl_funcs funcs = { 0 };
    EGLDeviceEXT device;
 
    if (!egl->gbm)
       return false;
 
-   if (!virgl_egl_get_interface(&funcs))
+   if (!has_bits(egl->extension_bits,
+                 EGL_EXT_PLATFORM_BASE |
+                 EGL_EXT_PLATFORM_DEVICE |
+                 EGL_EXT_DEVICE_ENUMERATION |
+                 EGL_EXT_DEVICE_QUERY))
       return false;
 
-   device = virgl_egl_get_device(egl, &funcs);
+   device = virgl_egl_get_device(egl);
 
    if (device == EGL_NO_DEVICE_EXT)
       return false;
 
-   egl->egl_display = funcs.eglGetPlatformDisplay(EGL_PLATFORM_DEVICE_EXT, device, NULL);
+   egl->egl_display = egl->funcs.eglGetPlatformDisplay(EGL_PLATFORM_DEVICE_EXT, device, NULL);
    return true;
 }
 #endif /* ENABLE_MINIGBM_ALLOCATION */
@@ -320,6 +327,9 @@ struct virgl_egl *virgl_egl_init(EGLNativeDisplayType display_id, bool surfacele
 #endif
 
    egl->different_gpu = false;
+   extensions = eglQueryString(NULL, EGL_EXTENSIONS);
+   if (!virgl_egl_add_extensions(egl, extensions))
+      goto fail;
 
 #ifdef ENABLE_MINIGBM_ALLOCATION
    if (virgl_egl_get_display(egl)) {
@@ -327,20 +337,16 @@ struct virgl_egl *virgl_egl_init(EGLNativeDisplayType display_id, bool surfacele
    } else /* Fallback to surfaceless. */
 #endif
    if (has_egl_base) {
-      PFNEGLGETPLATFORMDISPLAYEXTPROC get_platform_display =
-         (PFNEGLGETPLATFORMDISPLAYEXTPROC) eglGetProcAddress ("eglGetPlatformDisplayEXT");
-
-      if (!get_platform_display)
-        goto fail;
-
+      if (!has_bit(egl->extension_bits, EGL_EXT_PLATFORM_BASE))
+         goto fail;
       if (surfaceless) {
-         egl->egl_display = get_platform_display (EGL_PLATFORM_SURFACELESS_MESA,
-                                                  EGL_DEFAULT_DISPLAY, NULL);
+         egl->egl_display = egl->funcs.eglGetPlatformDisplay(EGL_PLATFORM_SURFACELESS_MESA,
+                                                             EGL_DEFAULT_DISPLAY, NULL);
       }
 #ifdef ENABLE_GBM
       else
-         egl->egl_display = get_platform_display (EGL_PLATFORM_GBM_KHR,
-                                                 (EGLNativeDisplayType)egl->gbm->device, NULL);
+         egl->egl_display = egl->funcs.eglGetPlatformDisplay(EGL_PLATFORM_GBM_KHR,
+                                                             (EGLNativeDisplayType)egl->gbm->device, NULL);
 #endif
    } else {
 #ifdef ENABLE_GBM
@@ -379,7 +385,10 @@ struct virgl_egl *virgl_egl_init(EGLNativeDisplayType display_id, bool surfacele
    vrend_printf( "EGL extensions: %s\n", extensions);
 #endif
 
-   if (virgl_egl_init_extensions(egl, extensions))
+   if (!virgl_egl_add_extensions(egl, extensions))
+      goto fail;
+
+   if (!virgl_egl_check_extensions(egl))
       goto fail;
 
    if (gles)
@@ -442,6 +451,10 @@ struct virgl_egl *virgl_egl_init_external(EGLDisplay egl_display)
 
    egl->egl_display = egl_display;
 
+   extensions = eglQueryString(NULL, EGL_EXTENSIONS);
+   if (!virgl_egl_add_extensions(egl, extensions))
+      goto fail;
+
    extensions = eglQueryString(egl->egl_display, EGL_EXTENSIONS);
 #ifdef VIRGL_EGL_DEBUG
    vrend_printf( "EGL version: %s\n",
@@ -450,11 +463,11 @@ struct virgl_egl *virgl_egl_init_external(EGLDisplay egl_display)
            eglQueryString(egl->egl_display, EGL_VENDOR));
    vrend_printf( "EGL extensions: %s\n", extensions);
 #endif
+   if (!virgl_egl_add_extensions(egl, extensions))
+      goto fail;
 
-   if (virgl_egl_init_extensions(egl, extensions)) {
-      free(egl);
-      return NULL;
-   }
+   if (!virgl_egl_check_extensions(egl))
+      goto fail;
 
 #ifdef ENABLE_GBM
    gbm = virgl_gbm_init(-1);
@@ -462,6 +475,9 @@ struct virgl_egl *virgl_egl_init_external(EGLDisplay egl_display)
 #endif
 
    return egl;
+fail:
+   free(egl);
+   return NULL;
 }
 
 virgl_renderer_gl_context virgl_egl_create_context(struct virgl_egl *egl, struct virgl_gl_ctx_param *vparams)