[Mesa-dev] [PATCH v3 05/14] i965/screen: Allocate ZEROED BOs for images

[Chad Versace]

On Wed 12 Jul 2017, Jason Ekstrand wrote:
> ---
>  src/mesa/drivers/dri/i965/intel_screen.c | 11 ++++++++++-
>  1 file changed, 10 insertions(+), 1 deletion(-)

> +   /* We request that the bufmgr zero the buffer for us for two reasons:
> +    *
> +    *  1) If a buffer gets re-used from the pool, we don't want to leak random
> +    *     garbage from our process to some other.
> +    *
> +    *  2) For images with CCS_E, we want to ensure that the CCS starts off in
> +    *     a valid state.  A CCS value of 0 indicates that the given block is
> +    *     in the pass-through state which is what we want.
> +    */

Bullet #2 should be postponed to a later patch, as the bo here does not
contain an aux surface until later in the series.

But that's a small nit. This is
Reviewed-by: Chad Versace <chadversary at chromium.org>

>     image->bo = brw_bo_alloc_tiled(screen->bufmgr, "image", surf.size,
>                                    isl_tiling_to_i915_tiling(mod_info->tiling),
> -                                  surf.row_pitch, 0);
> +                                  surf.row_pitch, BO_ALLOC_ZEROED);