[Intel-gfx] [RFC 21/39] drm/i915: Added scheduler flush calls to ring throttle and idle functions

[John.C.Harrison at Intel.com]

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

When requesting that all GPU work is completed, it is now necessary to get the
scheduler involved in order to flush out work that queued and not yet submitted.

Change-Id: I95dcc2a2ee5c1a844748621c333994ddd6cf6a66
For: VIZ-1587
Signed-off-by: John Harrison <John.C.Harrison at Intel.com>
---
 drivers/gpu/drm/i915/i915_gem.c       | 17 ++++++++++++-
 drivers/gpu/drm/i915/i915_scheduler.c | 45 +++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_scheduler.h |  1 +
 3 files changed, 62 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index dd9ebbe..6142e68 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3710,6 +3710,10 @@ int i915_gpu_idle(struct drm_device *dev)
 
 	/* Flush everything onto the inactive list. */
 	for_each_ring(ring, dev_priv, i) {
+		ret = i915_scheduler_flush(ring, true);
+		if (ret < 0)
+			return ret;
+
 		if (!i915.enable_execlists) {
 			struct drm_i915_gem_request *req;
 
@@ -4679,7 +4683,8 @@ i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file)
 	unsigned long recent_enough = jiffies - DRM_I915_THROTTLE_JIFFIES;
 	struct drm_i915_gem_request *request, *target = NULL;
 	unsigned reset_counter;
-	int ret;
+	int i, ret;
+	struct intel_engine_cs *ring;
 
 	ret = i915_gem_wait_for_error(&dev_priv->gpu_error);
 	if (ret)
@@ -4689,6 +4694,16 @@ i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file)
 	if (ret)
 		return ret;
 
+	for_each_ring(ring, dev_priv, i) {
+		/* Need a mechanism to flush out scheduler entries that were
+		 * submitted more than 'recent_enough' time ago as well! In the
+		 * meantime, just flush everything out to ensure that entries
+		 * can not sit around indefinitely. */
+		ret = i915_scheduler_flush(ring, false);
+		if (ret < 0)
+			return ret;
+	}
+
 	spin_lock(&file_priv->mm.lock);
 	list_for_each_entry(request, &file_priv->mm.request_list, client_list) {
 		if (time_after_eq(request->emitted_jiffies, recent_enough))
diff --git a/drivers/gpu/drm/i915/i915_scheduler.c b/drivers/gpu/drm/i915/i915_scheduler.c
index 811cbe4..73c9ba6 100644
--- a/drivers/gpu/drm/i915/i915_scheduler.c
+++ b/drivers/gpu/drm/i915/i915_scheduler.c
@@ -653,6 +653,51 @@ int i915_scheduler_flush_request(struct drm_i915_gem_request *req,
 	return flush_count;
 }
 
+int i915_scheduler_flush(struct intel_engine_cs *ring, bool is_locked)
+{
+	struct i915_scheduler_queue_entry *node;
+	struct drm_i915_private           *dev_priv;
+	struct i915_scheduler             *scheduler;
+	unsigned long       flags;
+	bool        found;
+	int         ret;
+	uint32_t    count = 0;
+
+	if (!ring)
+		return -EINVAL;
+
+	dev_priv  = ring->dev->dev_private;
+	scheduler = dev_priv->scheduler;
+
+	if (!scheduler)
+		return 0;
+
+	BUG_ON(is_locked && (scheduler->flags[ring->id] & i915_sf_submitting));
+
+	do {
+		found = false;
+		spin_lock_irqsave(&scheduler->lock, flags);
+		list_for_each_entry(node, &scheduler->node_queue[ring->id], link) {
+			if (!I915_SQS_IS_QUEUED(node))
+				continue;
+
+			found = true;
+			break;
+		}
+		spin_unlock_irqrestore(&scheduler->lock, flags);
+
+		if (found) {
+			ret = i915_scheduler_submit(ring, is_locked);
+			if (ret < 0)
+				return ret;
+
+			count += ret;
+		}
+	} while (found);
+
+	return count;
+}
+
 static void i915_scheduler_priority_bump_clear(struct i915_scheduler *scheduler)
 {
 	struct i915_scheduler_queue_entry *node;
diff --git a/drivers/gpu/drm/i915/i915_scheduler.h b/drivers/gpu/drm/i915/i915_scheduler.h
index fcf2640..5e094d5 100644
--- a/drivers/gpu/drm/i915/i915_scheduler.h
+++ b/drivers/gpu/drm/i915/i915_scheduler.h
@@ -92,6 +92,7 @@ void        i915_gem_scheduler_clean_node(struct i915_scheduler_queue_entry *nod
 int         i915_scheduler_queue_execbuffer(struct i915_scheduler_queue_entry *qe);
 int         i915_scheduler_handle_irq(struct intel_engine_cs *ring);
 void        i915_gem_scheduler_work_handler(struct work_struct *work);
+int         i915_scheduler_flush(struct intel_engine_cs *ring, bool is_locked);
 int         i915_scheduler_flush_request(struct drm_i915_gem_request *req,
 					 bool is_locked);
 bool        i915_scheduler_is_request_tracked(struct drm_i915_gem_request *req,
-- 
1.9.1