kdrive/fbdev: Don't try to accelerate rendering with glamor with a sw driver

It will likely be slower that unaccelerated rendering. Command-line flags were added for overriding this. Signed-off-by: stefan11111 <stefan11111@shitposting.expert>
2026-04-05 06:53:57 +00:00 · 2026-01-27 06:11:39 +02:00
parent f3c5b41161
commit 5adae6c3b3
5 changed files with 136 additions and 96 deletions
--- a/glamor/glamor.c
+++ b/glamor/glamor.c
@@ -835,75 +835,77 @@ glamor_init(ScreenPtr screen, unsigned int flags)
    if (!glamor_font_init(screen))
        goto fail;

-    glamor_priv->saved_procs.block_handler = screen->BlockHandler;
-    screen->BlockHandler = _glamor_block_handler;
+    if (!(flags & GLAMOR_NO_RENDER_ACCEL)) {
+        glamor_priv->saved_procs.block_handler = screen->BlockHandler;
+        screen->BlockHandler = _glamor_block_handler;

-    if (!glamor_composite_glyphs_init(screen)) {
-        ErrorF("Failed to initialize composite masks\n");
-        goto fail;
+        if (!glamor_composite_glyphs_init(screen)) {
+            ErrorF("Failed to initialize composite masks\n");
+            goto fail;
+        }
+
+        glamor_priv->saved_procs.create_gc = screen->CreateGC;
+        screen->CreateGC = glamor_create_gc;
+
+        glamor_priv->saved_procs.create_pixmap = screen->CreatePixmap;
+        screen->CreatePixmap = glamor_create_pixmap;
+
+        glamor_priv->saved_procs.get_spans = screen->GetSpans;
+        screen->GetSpans = glamor_get_spans;
+
+        glamor_priv->saved_procs.get_image = screen->GetImage;
+        screen->GetImage = glamor_get_image;
+
+        glamor_priv->saved_procs.change_window_attributes =
+            screen->ChangeWindowAttributes;
+        screen->ChangeWindowAttributes = glamor_change_window_attributes;
+
+        glamor_priv->saved_procs.copy_window = screen->CopyWindow;
+        screen->CopyWindow = glamor_copy_window;
+
+        glamor_priv->saved_procs.bitmap_to_region = screen->BitmapToRegion;
+        screen->BitmapToRegion = glamor_bitmap_to_region;
+
+        if (ps) {
+            glamor_priv->saved_procs.composite = ps->Composite;
+            ps->Composite = glamor_composite;
+
+            glamor_priv->saved_procs.trapezoids = ps->Trapezoids;
+            ps->Trapezoids = glamor_trapezoids;
+
+            glamor_priv->saved_procs.triangles = ps->Triangles;
+            ps->Triangles = glamor_triangles;
+
+            glamor_priv->saved_procs.addtraps = ps->AddTraps;
+            ps->AddTraps = glamor_add_traps;
+
+            glamor_priv->saved_procs.composite_rects = ps->CompositeRects;
+            ps->CompositeRects = glamor_composite_rectangles;
+
+            glamor_priv->saved_procs.glyphs = ps->Glyphs;
+            ps->Glyphs = glamor_composite_glyphs;
+        }
+
+        glamor_init_vbo(screen);
+
+        glamor_priv->enable_gradient_shader = TRUE;
+
+        if (!glamor_init_gradient_shader(screen)) {
+            LogMessage(X_WARNING,
+                       "glamor%d: Cannot initialize gradient shader, falling back to software rendering for gradients\n",
+                       screen->myNum);
+            glamor_priv->enable_gradient_shader = FALSE;
+        }
+
+        glamor_pixmap_init(screen);
+        glamor_sync_init(screen);
+
+        glamor_priv->screen = screen;
+
+        dixScreenHookClose(screen, glamor_close_screen);
+        dixScreenHookPixmapDestroy(screen, glamor_pixmap_destroy);
    }

-    glamor_priv->saved_procs.create_gc = screen->CreateGC;
-    screen->CreateGC = glamor_create_gc;
-
-    glamor_priv->saved_procs.create_pixmap = screen->CreatePixmap;
-    screen->CreatePixmap = glamor_create_pixmap;
-
-    glamor_priv->saved_procs.get_spans = screen->GetSpans;
-    screen->GetSpans = glamor_get_spans;
-
-    glamor_priv->saved_procs.get_image = screen->GetImage;
-    screen->GetImage = glamor_get_image;
-
-    glamor_priv->saved_procs.change_window_attributes =
-        screen->ChangeWindowAttributes;
-    screen->ChangeWindowAttributes = glamor_change_window_attributes;
-
-    glamor_priv->saved_procs.copy_window = screen->CopyWindow;
-    screen->CopyWindow = glamor_copy_window;
-
-    glamor_priv->saved_procs.bitmap_to_region = screen->BitmapToRegion;
-    screen->BitmapToRegion = glamor_bitmap_to_region;
-
-    if (ps) {
-        glamor_priv->saved_procs.composite = ps->Composite;
-        ps->Composite = glamor_composite;
-
-        glamor_priv->saved_procs.trapezoids = ps->Trapezoids;
-        ps->Trapezoids = glamor_trapezoids;
-
-        glamor_priv->saved_procs.triangles = ps->Triangles;
-        ps->Triangles = glamor_triangles;
-
-        glamor_priv->saved_procs.addtraps = ps->AddTraps;
-        ps->AddTraps = glamor_add_traps;
-
-        glamor_priv->saved_procs.composite_rects = ps->CompositeRects;
-        ps->CompositeRects = glamor_composite_rectangles;
-
-        glamor_priv->saved_procs.glyphs = ps->Glyphs;
-        ps->Glyphs = glamor_composite_glyphs;
-    }
-
-    glamor_init_vbo(screen);
-
-    glamor_priv->enable_gradient_shader = TRUE;
-
-    if (!glamor_init_gradient_shader(screen)) {
-        LogMessage(X_WARNING,
-                   "glamor%d: Cannot initialize gradient shader, falling back to software rendering for gradients\n",
-                   screen->myNum);
-        glamor_priv->enable_gradient_shader = FALSE;
-    }
-
-    glamor_pixmap_init(screen);
-    glamor_sync_init(screen);
-
-    glamor_priv->screen = screen;
-
-    dixScreenHookClose(screen, glamor_close_screen);
-    dixScreenHookPixmapDestroy(screen, glamor_pixmap_destroy);
-
    return TRUE;

 fail:
@@ -931,33 +933,38 @@ static void glamor_close_screen(CallbackListPtr *pcbl, ScreenPtr screen, void *u
    PixmapPtr screen_pixmap;

    glamor_priv = glamor_get_screen_private(screen);
-    glamor_sync_close(screen);
-    glamor_composite_glyphs_fini(screen);
-    glamor_set_glvnd_vendor(screen, NULL);
-
-    dixScreenUnhookClose(screen, glamor_close_screen);
-    dixScreenUnhookPixmapDestroy(screen, glamor_pixmap_destroy);
-
-    screen->CreateGC = glamor_priv->saved_procs.create_gc;
-    screen->CreatePixmap = glamor_priv->saved_procs.create_pixmap;
-    screen->GetSpans = glamor_priv->saved_procs.get_spans;
-    screen->ChangeWindowAttributes =
-        glamor_priv->saved_procs.change_window_attributes;
-    screen->CopyWindow = glamor_priv->saved_procs.copy_window;
-    screen->BitmapToRegion = glamor_priv->saved_procs.bitmap_to_region;
-    screen->BlockHandler = glamor_priv->saved_procs.block_handler;
-
-    PictureScreenPtr ps = GetPictureScreenIfSet(screen);
-    if (ps) {
-        ps->Composite = glamor_priv->saved_procs.composite;
-        ps->Trapezoids = glamor_priv->saved_procs.trapezoids;
-        ps->Triangles = glamor_priv->saved_procs.triangles;
-        ps->CompositeRects = glamor_priv->saved_procs.composite_rects;
-        ps->Glyphs = glamor_priv->saved_procs.glyphs;
+    if (!(glamor_priv->flags & GLAMOR_NO_RENDER_ACCEL)) {
+        glamor_sync_close(screen);
+        glamor_composite_glyphs_fini(screen);
    }

-    screen_pixmap = screen->GetScreenPixmap(screen);
-    glamor_pixmap_destroy_fbo(screen_pixmap);
+    glamor_set_glvnd_vendor(screen, NULL);
+
+    if (!(glamor_priv->flags & GLAMOR_NO_RENDER_ACCEL)) {
+        dixScreenUnhookClose(screen, glamor_close_screen);
+        dixScreenUnhookPixmapDestroy(screen, glamor_pixmap_destroy);
+
+        screen->CreateGC = glamor_priv->saved_procs.create_gc;
+        screen->CreatePixmap = glamor_priv->saved_procs.create_pixmap;
+        screen->GetSpans = glamor_priv->saved_procs.get_spans;
+        screen->ChangeWindowAttributes =
+            glamor_priv->saved_procs.change_window_attributes;
+        screen->CopyWindow = glamor_priv->saved_procs.copy_window;
+        screen->BitmapToRegion = glamor_priv->saved_procs.bitmap_to_region;
+        screen->BlockHandler = glamor_priv->saved_procs.block_handler;
+
+        PictureScreenPtr ps = GetPictureScreenIfSet(screen);
+        if (ps) {
+            ps->Composite = glamor_priv->saved_procs.composite;
+            ps->Trapezoids = glamor_priv->saved_procs.trapezoids;
+            ps->Triangles = glamor_priv->saved_procs.triangles;
+            ps->CompositeRects = glamor_priv->saved_procs.composite_rects;
+            ps->Glyphs = glamor_priv->saved_procs.glyphs;
+        }
+
+        screen_pixmap = screen->GetScreenPixmap(screen);
+        glamor_pixmap_destroy_fbo(screen_pixmap);
+    }

    glamor_release_screen_priv(screen);
 }
--- a/glamor/glamor.h
+++ b/glamor/glamor.h
@@ -65,10 +65,12 @@ typedef Bool (*GetDrawableModifiersFuncPtr) (DrawablePtr draw,
                                             uint64_t **modifiers);

 #define GLAMOR_EGL_EXTERNAL_BUFFER 3
-#define GLAMOR_USE_EGL_SCREEN		(1 << 0)
-#define GLAMOR_NO_DRI3			(1 << 1)
+#define GLAMOR_USE_EGL_SCREEN           (1 << 0)
+#define GLAMOR_NO_DRI3                  (1 << 1)
+#define GLAMOR_NO_RENDER_ACCEL          (1 << 2)
 #define GLAMOR_VALID_FLAGS      (GLAMOR_USE_EGL_SCREEN                \
-                                 | GLAMOR_NO_DRI3)
+                                 | GLAMOR_NO_DRI3                     \
+                                 | GLAMOR_NO_RENDER_ACCEL)

 /* until we need geometry shaders GL3.1 should suffice. */
 #define GLAMOR_GL_CORE_VER_MAJOR 3
--- a/hw/kdrive/fbdev/fb_glamor.c
+++ b/hw/kdrive/fbdev/fb_glamor.c
@@ -24,6 +24,8 @@ char *fbdev_glvnd_provider = NULL;

 Bool es_allowed = TRUE;
 Bool force_es = FALSE;
+Bool fbGlamorAllowed = TRUE;
+Bool fbForceGlamor = FALSE;
 Bool fbXVAllowed = TRUE;

 static void
@@ -97,7 +99,19 @@ fbdevInitAccel(ScreenPtr pScreen)
        return FALSE;
    }

-    if (!glamor_init(pScreen, GLAMOR_USE_EGL_SCREEN | GLAMOR_NO_DRI3)) {
+    int flags = GLAMOR_USE_EGL_SCREEN | GLAMOR_NO_DRI3;
+    if (!fbGlamorAllowed) {
+        flags |= GLAMOR_NO_RENDER_ACCEL;
+    } else if (!fbForceGlamor){
+        const char *renderer = (const char*)glGetString(GL_RENDERER);
+        if (!renderer ||
+            strstr(renderer, "softpipe") ||
+            strstr(renderer, "llvmpipe")) {
+            flags |= GLAMOR_NO_RENDER_ACCEL;
+        }
+    }
+
+    if (!glamor_init(pScreen, flags)) {
        fbdev_glamor_egl_cleanup(scrpriv);
        return FALSE;
    }
@@ -112,7 +126,8 @@ fbdevInitAccel(ScreenPtr pScreen)
 #endif

 #ifdef XV
-    if (fbXVAllowed) {
+    /* X-Video needs glamor render accel */
+    if (fbXVAllowed && !(flags & GLAMOR_NO_RENDER_ACCEL)) {
        kd_glamor_xv_init(pScreen);
    }
 #endif
--- a/hw/kdrive/fbdev/fbdev.h
+++ b/hw/kdrive/fbdev/fbdev.h
@@ -66,6 +66,8 @@ extern Bool fbDisableShadow;
 extern char *fbdev_glvnd_provider;
 extern Bool es_allowed;
 extern Bool force_es;
+extern Bool fbGlamorAllowed;
+extern Bool fbForceGlamor;
 #ifdef XV
 extern Bool fbXVAllowed;
 #endif
--- a/hw/kdrive/fbdev/fbinit.c
+++ b/hw/kdrive/fbdev/fbinit.c
@@ -72,6 +72,10 @@ ddxUseMsg(void)
        ("-fb path         Framebuffer device to use. Defaults to /dev/fb0\n");
    ErrorF
        ("-noshadow        Disable the ShadowFB layer if possible\n");
+    ErrorF
+        ("-glamor          Force enable glamor render acceleration if possible\n");
+    ErrorF
+        ("-noglamor        Force disable glamor render acceleration\n");
    ErrorF
        ("-glvendor        Suggest what glvnd vendor library should be used\n");
    ErrorF
@@ -101,6 +105,16 @@ ddxProcessArgument(int argc, char **argv, int i)
    }

 #ifdef GLAMOR
+    if (!strcmp(argv[i], "-glamor")) {
+        fbForceGlamor = TRUE;
+        return 1;
+    }
+
+    if (!strcmp(argv[i], "-noglamor")) {
+        fbGlamorAllowed = FALSE;
+        return 1;
+    }
+
    if (!strcmp(argv[i], "-glvendor")) {
        if (i + 1 < argc) {
            fbdev_glvnd_provider = strdup(argv[i + 1]);