[PATCH 8/9] drm/i915: mark up internal objects with start_cpu_write

[Thomas Hellström]

On Mon, 2021-10-18 at 18:45 +0100, Matthew Auld wrote:
> While the pages can't be swapped out, they can be discarded by the
> shrinker.
> Normally such objects are marked with __I915_MADV_PURGED, which can't
> be
> unset, and therefore requires a new object. For kernel internal
> objects
> this is not true, since the madv hint is reset for our special
> volatile
> objects, such that we can re-acquire new pages, if so desired,
> without
> needing a new object. As a result we should probably be paranoid here
> and put the object back into the CPU domain when discarding the
> pages,
> and also correctly set cache_dirty, if required.
> 
> Signed-off-by: Matthew Auld <matthew.auld at intel.com>
> Cc: Thomas Hellström <thomas.hellstrom at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/gem/i915_gem_internal.c | 2 ++
>  1 file changed, 2 insertions(+)

Reviewed-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>