[Intel-gfx] [PATCH 3/4] drm/i915: Skip adding the request to the signal tree is complete

[Joonas Lahtinen]

On ma, 2017-06-05 at 11:26 +0100, Chris Wilson wrote:
> Enabling the interrupt for the signaler takes a finite amount of time (a
> few microseconds) during which it is possible for the request to
> complete. Check afterwards and skip adding the request to the signal
> rbtree if it complete.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

<SNIP>

> +++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c
> @@ -714,27 +714,33 @@ void intel_engine_enable_signaling(struct drm_i915_gem_request *request,
> +	if (!__i915_gem_request_completed(request, seqno)) {
> +		/* Now insert ourselves into the retirement ordered list of
> +		 * signals on this engine. We track the oldest seqno as that
> +		 * will be the first signal to complete.
> +		 */
> +		parent = NULL;
> +		first = true;
> +		p = &b->signals.rb_node;

These variables could be more tightly scoped now.

> +		while (*p) {
> +			parent = *p;
> +			if (i915_seqno_passed(seqno,
> +						to_signaler(parent)->signaling.wait.seqno)) {

Alignment incorrect.

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

Regards, Joonas
-- 
Joonas Lahtinen
Open Source Technology Center
Intel Corporation