[Intel-gfx] [PATCH 08/10] drm/i915: Prelude to splitting i915_gem_do_execbuffer in two

[John.C.Harrison at Intel.com]

From: John Harrison <John.C.Harrison at Intel.com>

The scheduler decouples the submission of batch buffers to the driver with their
submission to the hardware. This basically means splitting the execbuffer()
function in half. This change rearranges some code ready for the split to occur.

Change-Id: Icc9c8afaac18821f3eb8a151a49f918f90c068a3
For: VIZ-1587
Signed-off-by: John Harrison <John.C.Harrison at Intel.com>
---
 drivers/gpu/drm/i915/i915_gem_execbuffer.c |   47 +++++++++++++++++-----------
 drivers/gpu/drm/i915/intel_lrc.c           |   17 +++++++---
 2 files changed, 40 insertions(+), 24 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index f09501c..a339556 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -848,10 +848,7 @@ i915_gem_execbuffer_move_to_gpu(struct intel_engine_cs *ring,
 	if (flush_domains & I915_GEM_DOMAIN_GTT)
 		wmb();
 
-	/* Unconditionally invalidate gpu caches and ensure that we do flush
-	 * any residual writes from the previous batch.
-	 */
-	return intel_ring_invalidate_all_caches(ring);
+	return 0;
 }
 
 static bool
@@ -1123,14 +1120,6 @@ i915_gem_ringbuffer_submission(struct drm_device *dev, struct drm_file *file,
 		}
 	}
 
-	ret = i915_gem_execbuffer_move_to_gpu(ring, vmas);
-	if (ret)
-		goto error;
-
-	ret = i915_switch_context(ring, ctx);
-	if (ret)
-		goto error;
-
 	instp_mode = args->flags & I915_EXEC_CONSTANTS_MASK;
 	instp_mask = I915_EXEC_CONSTANTS_MASK;
 	switch (instp_mode) {
@@ -1168,6 +1157,28 @@ i915_gem_ringbuffer_submission(struct drm_device *dev, struct drm_file *file,
 		goto error;
 	}
 
+	ret = i915_gem_execbuffer_move_to_gpu(ring, vmas);
+	if (ret)
+		goto error;
+
+	i915_gem_execbuffer_move_to_active(vmas, ring);
+
+	/* To be split into two functions here... */
+
+	intel_runtime_pm_get(dev_priv);
+
+	/* Unconditionally invalidate gpu caches and ensure that we do flush
+	 * any residual writes from the previous batch.
+	 */
+	ret = intel_ring_invalidate_all_caches(ring);
+	if (ret)
+		goto error;
+
+	/* Switch to the correct context for the batch */
+	ret = i915_switch_context(ring, ctx);
+	if (ret)
+		goto error;
+
 	if (ring == &dev_priv->ring[RCS] &&
 			instp_mode != dev_priv->relative_constants_mode) {
 		ret = intel_ring_begin(ring, 4);
@@ -1208,15 +1219,18 @@ i915_gem_ringbuffer_submission(struct drm_device *dev, struct drm_file *file,
 						exec_start, exec_len,
 						dispatch_flags);
 		if (ret)
-			return ret;
+			goto error;
 	}
 
 	trace_i915_gem_ring_dispatch(intel_ring_get_request(ring), dispatch_flags);
 
-	i915_gem_execbuffer_move_to_active(vmas, ring);
 	i915_gem_execbuffer_retire_commands(dev, file, ring, batch_obj);
 
 error:
+	/* intel_gpu_busy should also get a ref, so it will free when the device
+	 * is really idle. */
+	intel_runtime_pm_put(dev_priv);
+
 	kfree(cliprects);
 	return ret;
 }
@@ -1335,8 +1349,6 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
 		return -EINVAL;
 	}
 
-	intel_runtime_pm_get(dev_priv);
-
 	ret = i915_mutex_lock_interruptible(dev);
 	if (ret)
 		goto pre_mutex_err;
@@ -1467,9 +1479,6 @@ err:
 	mutex_unlock(&dev->struct_mutex);
 
 pre_mutex_err:
-	/* intel_gpu_busy should also get a ref, so it will free when the device
-	 * is really idle. */
-	intel_runtime_pm_put(dev_priv);
 	return ret;
 }
 
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 037cbd5..f16b15d 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -630,10 +630,7 @@ static int execlists_move_to_gpu(struct intel_ringbuffer *ringbuf,
 	if (flush_domains & I915_GEM_DOMAIN_GTT)
 		wmb();
 
-	/* Unconditionally invalidate gpu caches and ensure that we do flush
-	 * any residual writes from the previous batch.
-	 */
-	return logical_ring_invalidate_all_caches(ringbuf);
+	return 0;
 }
 
 /**
@@ -717,6 +714,17 @@ int intel_execlists_submission(struct drm_device *dev, struct drm_file *file,
 	if (ret)
 		return ret;
 
+	i915_gem_execbuffer_move_to_active(vmas, ring);
+
+	/* To be split into two functions here... */
+
+	/* Unconditionally invalidate gpu caches and ensure that we do flush
+	 * any residual writes from the previous batch.
+	 */
+	ret = logical_ring_invalidate_all_caches(ringbuf);
+	if (ret)
+		return ret;
+
 	if (ring == &dev_priv->ring[RCS] &&
 	    instp_mode != dev_priv->relative_constants_mode) {
 		ret = intel_logical_ring_begin(ringbuf, 4);
@@ -738,7 +746,6 @@ int intel_execlists_submission(struct drm_device *dev, struct drm_file *file,
 
 	trace_i915_gem_ring_dispatch(intel_ring_get_request(ring), dispatch_flags);
 
-	i915_gem_execbuffer_move_to_active(vmas, ring);
 	i915_gem_execbuffer_retire_commands(dev, file, ring, batch_obj);
 
 	return 0;
-- 
1.7.9.5