[PATCH xserver 3/4] glamor: Drop glamor_set_screen_pixmap().

[Keith Packard]

Eric Anholt <eric at anholt.net> writes:

> All that was left here was updating the FBO's size.  However, the FBO
> size was always set correctly already through
> glamor_set_pixmap_texture() from whoever had attached a new BO to the
> pixmap.

I remember desperately needing this code at some point; do you have any
idea what has changed which makes that no longer true?

The key path to understand is when the screen is resized; I think
server start up is at least easier to validate. My brain is starting to
hurt from tracing this by hand

xf86RandR12ScreenSetSize
        drmmode_xf86crtc_resize
		drmmode_create_bo
			gbm_bo_create
		screen->ModifyPixmapHeader (miModifyPixmapHeader)
                        pPixmap->drawable.width = width;
                        pPixmap->drawable.height = height;
		drmmode_glamor_handle_new_screen_pixmap
                        drmmode_set_pixmap_bo
                                glamor_egl_create_textured_pixmap_from_gbm_bo
                                        glamor_set_pixmap_texture
                                                glamor_create_fbo_from_tex
                                                        fbo->width = w;
                                                        fbo->height = h;
                        glamor_set_screen_pixmap
                                pixmap_priv->fbo->width = screen_pixmap->drawable.width;
                                pixmap_priv->fbo->height = screen_pixmap->drawable.height;

	pScreen->width = pScrnPix->drawable.width = width;
	pScreen->height = pScrnPix->drawable.height = height;

I don't see any conditionals in this call graph that could avoid setting
the screen pixmap size in miModifyPixmapHeader and the fbo size in
glamor_create_fbo_from_tex, whicm means the extra call to
glamor_set_screen_pixmap is not necessary.

Note that xf86RandR12ScreenSetSize also sets the pixmap size again,
which was probably necessary before drivers regularly supported
reallocating the screen pixmap.

(the other three patches were trivial)

For the series:

Reviewed-by: Keith Packard <keithp at keithp.com>

-- 
-keith
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