[Intel-gfx] [PATCH v3 1/3] drm/i915: simplify allocation of driver-internal requests

[Chris Wilson]

On Thu, Jan 07, 2016 at 10:20:50AM +0000, Dave Gordon wrote:
> There are a number of places where the driver needs a request, but isn't
> working on behalf of any specific user or in a specific context. At
> present, we associate them with the per-engine default context. A future
> patch will abolish those per-engine context pointers; but we can already
> eliminate a lot of the references to them, just by making the allocator
> allow NULL as a shorthand for "an appropriate context for this ring",
> which will mean that the callers don't need to know anything about how
> the "appropriate context" is found (e.g. per-ring vs per-device, etc).
> 
> So this patch renames the existing i915_gem_request_alloc(), and makes
> it local (static inline), and replaces it with a wrapper that provides
> a default if the context is NULL, and also has a nicer calling
> convention (doesn't require a pointer to an output parameter). Then we
> change all callers to use the new convention:
> OLD:
> 	err = i915_gem_request_alloc(ring, user_ctx, &req);
> 	if (err) ...
> NEW:
> 	req = i915_gem_request_alloc(ring, user_ctx);
> 	if (IS_ERR(req)) ...
> OLD:
> 	err = i915_gem_request_alloc(ring, ring->default_context, &req);
> 	if (err) ...
> NEW:
> 	req = i915_gem_request_alloc(ring, NULL);
> 	if (IS_ERR(req)) ...

Nak. You haven't fixed i915_gem_request_alloc() at all.

http://cgit.freedesktop.org/~ickle/linux-2.6/commit/?h=breadcrumbs&id=82c72e1a2b4385f0ab07dccee45acef38303e96f
is the patch I have been carrying ever since.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre