[Intel-gfx] [PATCH 145/190] drm/i915: Stop discarding GTT cache-domain on unbind vma

[Joonas Lahtinen]

On ma, 2016-01-11 at 11:00 +0000, Chris Wilson wrote:
> Since
> 
> commit 43566dedde54f9729113f5f9fde77d53e75e61e9
> Author: Chris Wilson <chris at chris-wilson.co.uk>
> Date:   Fri Jan 2 16:29:29 2015 +0530
> 
>     drm/i915: Broaden application of set-domain(GTT)
> 
> we allowed objects to be in the GTT domain, but unbound. Therefore
> removing the GTT cache domain when removing the GGTT vma is no longer
> semantically correct.
> 
> An unfortunate side-effect is we lose the wondrously named
> i915_gem_object_finish_gtt(), not to be confused with
> i915_gem_gtt_finish_object()!
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Akash Goel <akash.goel at intel.com>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>

I'm fairly sure I did this already in the past, but here goes again...

Reviewed-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>

> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_gem.c | 26 +++-----------------------
>  1 file changed, 3 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem.c
> b/drivers/gpu/drm/i915/i915_gem.c
> index 6ceed074f738..08287d8857c9 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -2618,27 +2618,6 @@ i915_gem_object_sync(struct
> drm_i915_gem_object *obj,
>  	return 0;
>  }
>  
> -static void i915_gem_object_finish_gtt(struct drm_i915_gem_object
> *obj)
> -{
> -	u32 old_write_domain, old_read_domains;
> -
> -	/* Force a pagefault for domain tracking on next user access
> */
> -	i915_gem_release_mmap(obj);
> -
> -	if ((obj->base.read_domains & I915_GEM_DOMAIN_GTT) == 0)
> -		return;
> -
> -	old_read_domains = obj->base.read_domains;
> -	old_write_domain = obj->base.write_domain;
> -
> -	obj->base.read_domains &= ~I915_GEM_DOMAIN_GTT;
> -	obj->base.write_domain &= ~I915_GEM_DOMAIN_GTT;
> -
> -	trace_i915_gem_object_change_domain(obj,
> -					    old_read_domains,
> -					    old_write_domain);
> -}
> -
>  static void i915_vma_destroy(struct i915_vma *vma)
>  {
>  	GEM_BUG_ON(vma->node.allocated);
> @@ -2691,13 +2670,14 @@ int i915_vma_unbind(struct i915_vma *vma)
>  	GEM_BUG_ON(obj->pages == NULL);
>  
>  	if (vma->map_and_fenceable) {
> -		i915_gem_object_finish_gtt(obj);
> -
>  		/* release the fence reg _after_ flushing */
>  		ret = i915_vma_put_fence(vma);
>  		if (ret)
>  			return ret;
>  
> +		/* Force a pagefault for domain tracking on next
> user access */
> +		i915_gem_release_mmap(obj);
> +
>  		if (vma->iomap) {
>  			iounmap(vma->iomap);
>  			vma->iomap = NULL;
-- 
Joonas Lahtinen
Open Source Technology Center
Intel Corporation