[Intel-gfx] [RFC 04/21] drm/i915: Add reference count to request structure

[John.C.Harrison at Intel.com]

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

For: VIZ-4377
Signed-off-by: John.C.Harrison at Intel.com
---
 drivers/gpu/drm/i915/i915_drv.h         |   16 ++++++++++++++++
 drivers/gpu/drm/i915/i915_gem.c         |   20 ++++++++++++++++----
 drivers/gpu/drm/i915/intel_lrc.c        |    2 ++
 drivers/gpu/drm/i915/intel_ringbuffer.c |    2 ++
 4 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index e3ca8df..e1858e7 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1913,6 +1913,8 @@ void i915_gem_track_fb(struct drm_i915_gem_object *old,
  * an emission time with seqnos for tracking how far ahead of the GPU we are.
  */
 struct drm_i915_gem_request {
+	struct kref ref;
+
 	/** On Which ring this request was generated */
 	struct intel_engine_cs *ring;
 
@@ -1942,6 +1944,20 @@ struct drm_i915_gem_request {
 	struct list_head client_list;
 };
 
+void i915_gem_request_free(struct kref *req_ref);
+
+static inline void
+i915_gem_request_reference(struct drm_i915_gem_request *req)
+{
+	kref_get(&req->ref);
+}
+
+static inline void
+i915_gem_request_unreference(struct drm_i915_gem_request *req)
+{
+	kref_put(&req->ref, i915_gem_request_free);
+}
+
 struct drm_i915_file_private {
 	struct drm_i915_private *dev_priv;
 	struct drm_file *file;
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index aa2d882..2555cd8 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2379,6 +2379,8 @@ int __i915_add_request(struct intel_engine_cs *ring,
 			return ret;
 	}
 
+	i915_gem_request_reference(request);
+
 	request->seqno = intel_ring_get_seqno(ring);
 	request->ring = ring;
 	request->head = request_start;
@@ -2495,12 +2497,22 @@ static void i915_set_reset_status(struct drm_i915_private *dev_priv,
 static void i915_gem_free_request(struct drm_i915_gem_request *request)
 {
 	list_del(&request->list);
-	i915_gem_request_remove_from_client(request);
 
-	if (request->ctx)
-		i915_gem_context_unreference(request->ctx);
+	i915_gem_request_unreference(request);
+}
+
+void i915_gem_request_free(struct kref *req_ref)
+{
+	struct drm_i915_gem_request *req = container_of(req_ref,
+						 typeof(*req), ref);
+
+	/*list_del(&req->list);*/
+	i915_gem_request_remove_from_client(req);
+
+	if (req->ctx)
+		i915_gem_context_unreference(req->ctx);
 
-	kfree(request);
+	kfree(req);
 }
 
 struct drm_i915_gem_request *
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 3ac2622..b5b6430 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -814,6 +814,8 @@ static int logical_ring_alloc_seqno(struct intel_engine_cs *ring,
 	if (request == NULL)
 		return -ENOMEM;
 
+	kref_init(&request->ref);
+
 	ret = i915_gem_get_seqno(ring->dev, &ring->outstanding_lazy_seqno);
 	if (ret) {
 		kfree(request);
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index cceac67..7350f78 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -2019,6 +2019,8 @@ intel_ring_alloc_seqno(struct intel_engine_cs *ring)
 	if (request == NULL)
 		return -ENOMEM;
 
+	kref_init(&request->ref);
+
 	ret = i915_gem_get_seqno(ring->dev, &ring->outstanding_lazy_seqno);
 	if (ret) {
 		kfree(request);
-- 
1.7.9.5