[52/55] drm/i915: Remove 'faked' request from LRC submission

Commit Message

John Harrison May 29, 2015, 4:44 p.m. UTC

From: John Harrison <[e-mail]>

The LRC submission code requires a request for tracking purposes. It does not
actually require that request to 'complete' it simply uses it for keeping hold
of reference counts on contexts and such like.

Previously, the fall back path of polling for space in the ring would start by
submitting any outstanding work that was sat in the buffer. This submission was
not done as part of the request that that work was owned by because that would
lead to complications with the request being submitted twice. Instead, a null
request structure was passed in to the submit call and a fake one was created.

That fall back path has long since been obsoleted and has now been removed. Thus
there is never any need to fake up a request structure. This patch removes that
code. A couple of sanity check warnings are added as well, just in case.

For: VIZ-5115
Signed-off-by: John Harrison <[e-mail]>
Reviewed-by: Thomas Daniel <[e-mail]>
Reviewed-by: Tomas Elf <[e-mail]>
---
 drivers/gpu/drm/i915/intel_lrc.c |   23 +++++------------------
 1 file changed, 5 insertions(+), 18 deletions(-)

Patch

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 0421480..323a4a1 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -549,29 +549,16 @@  static int execlists_context_queue(struct intel_engine_cs *ring,
 				   struct drm_i915_gem_request *request)
 {
 	struct drm_i915_gem_request *cursor;
-	struct drm_i915_private *dev_priv = ring->dev->dev_private;
 	int num_elements = 0;
 
 	if (to != ring->default_context)
 		intel_lr_context_pin(ring, to);
 
-	if (!request) {
-		/*
-		 * If there isn't a request associated with this submission,
-		 * create one as a temporary holder.
-		 */
-		request = kzalloc(sizeof(*request), GFP_KERNEL);
-		if (request == NULL)
-			return -ENOMEM;
-		request->ring = ring;
-		request->ctx = to;
-		kref_init(&request->ref);
-		request->uniq = dev_priv->request_uniq++;
-		i915_gem_context_reference(request->ctx);
-	} else {
-		i915_gem_request_reference(request);
-		WARN_ON(to != request->ctx);
-	}
+	WARN_ON(!request);
+	WARN_ON(to != request->ctx);
+
+	i915_gem_request_reference(request);
+
 	request->tail = tail;
 
 	spin_lock_irq(&ring->execlist_lock);