Re: [PATCH 01/13] drm/i915: Flush the context object from the CPU caches upon creation

[Daniel Vetter <daniel@ffwll.ch>]

On Fri, Jul 13, 2012 at 02:14:04PM +0100, Chris Wilson wrote:
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Ben Widawsky <ben@bwidawsk.net>
> ---
>  drivers/gpu/drm/i915/i915_gem_context.c |   12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
> index 9ae3f2c..90857f8 100644
> --- a/drivers/gpu/drm/i915/i915_gem_context.c
> +++ b/drivers/gpu/drm/i915/i915_gem_context.c
> @@ -225,6 +225,13 @@ static int create_default_context(struct drm_i915_private *dev_priv)
>  		return ret;
>  	}
>  
> +	ret = i915_gem_object_set_to_gtt_domain(ctx->obj, true);
> +	if (ret) {
> +		i915_gem_object_unpin(ctx->obj);
> +		do_destroy(ctx);
> +		return ret;
> +	}
> +
>  	ret = do_switch(NULL, ctx, 0);
>  	if (ret) {
>  		i915_gem_object_unpin(ctx->obj);
> @@ -396,8 +403,6 @@ static int do_switch(struct drm_i915_gem_object *from_obj,
>  	 * MI_SET_CONTEXT instead of when the next seqno has completed.
>  	 */
>  	if (from_obj != NULL) {
> -		from_obj->base.read_domains = I915_GEM_DOMAIN_INSTRUCTION;
> -		i915_gem_object_move_to_active(from_obj, ring, seqno);
>  		/* As long as MI_SET_CONTEXT is serializing, ie. it flushes the
>  		 * whole damn pipeline, we don't need to explicitly mark the
>  		 * object dirty. The only exception is that the context must be
> @@ -405,6 +410,9 @@ static int do_switch(struct drm_i915_gem_object *from_obj,
>  		 * able to defer doing this until we know the object would be
>  		 * swapped, but there is no way to do that yet.
>  		 */
> +		from_obj->base.write_domain = I915_GEM_DOMAIN_INSTRUCTION;
> +		from_obj->base.read_domains = I915_GEM_DOMAIN_INSTRUCTION;
> +		i915_gem_object_move_to_active(from_obj, ring, seqno);
>  		from_obj->dirty = 1;
>  		BUG_ON(from_obj->ring != to->ring);
>  		i915_gem_object_unpin(from_obj);

I think only the first hunk should be part of this patch - the later two
hunks make more sense squashed together with the last patch. At least that
would avoid me going a bit wtf here and then again on the last patch where
the from_obj->dirty=1 gets removed and smashed into move_to_active. Until
I've realized what's going on here ;-)
-Daniel
-- 
Daniel Vetter
Mail: daniel@ffwll.ch
Mobile: +41 (0)79 365 57 48