[Intel-gfx] [PATCH v2 1/2] drm/i915/scheduler: add gvt force-single-submission for guc

[Chuanxiao Dong]

GVT needs single submission and cannot allow merge. So when GuC submitting
a GVT request, the next one should be submitted to guc later until the
previous one is completed. This is following the usage when using execlist
mode submission.

v2: make force-single-submission specific to gvt (Chris)

Cc: chris at chris-wilson.co.uk
Signed-off-by: Chuanxiao Dong <chuanxiao.dong at intel.com>
---
 drivers/gpu/drm/i915/i915_guc_submission.c |  7 ++++++-
 drivers/gpu/drm/i915/intel_gvt.h           | 11 +++++++++++
 drivers/gpu/drm/i915/intel_lrc.c           | 25 ++++---------------------
 3 files changed, 21 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
index 991e76e..58087630 100644
--- a/drivers/gpu/drm/i915/i915_guc_submission.c
+++ b/drivers/gpu/drm/i915/i915_guc_submission.c
@@ -680,10 +680,15 @@ static bool i915_guc_dequeue(struct intel_engine_cs *engine)
 		struct drm_i915_gem_request *rq =
 			rb_entry(rb, typeof(*rq), priotree.node);
 
-		if (last && rq->ctx != last->ctx) {
+		if (last && ((last->ctx != rq->ctx) ||
+			intel_gvt_context_single_port_submit(last->ctx))) {
 			if (port != engine->execlist_port)
 				break;
 
+			if (intel_gvt_context_single_port_submit(last->ctx) ||
+				intel_gvt_context_single_port_submit(rq->ctx))
+				break;
+
 			i915_gem_request_assign(&port->request, last);
 			nested_enable_signaling(last);
 			port++;
diff --git a/drivers/gpu/drm/i915/intel_gvt.h b/drivers/gpu/drm/i915/intel_gvt.h
index 25df2d6..c0dcd66 100644
--- a/drivers/gpu/drm/i915/intel_gvt.h
+++ b/drivers/gpu/drm/i915/intel_gvt.h
@@ -32,6 +32,12 @@ void intel_gvt_cleanup(struct drm_i915_private *dev_priv);
 int intel_gvt_init_device(struct drm_i915_private *dev_priv);
 void intel_gvt_clean_device(struct drm_i915_private *dev_priv);
 int intel_gvt_init_host(void);
+
+static inline bool
+intel_gvt_context_single_port_submit(const struct i915_gem_context *ctx)
+{
+	return i915_gem_context_force_single_submission(ctx);
+}
 #else
 static inline int intel_gvt_init(struct drm_i915_private *dev_priv)
 {
@@ -40,6 +46,11 @@ static inline int intel_gvt_init(struct drm_i915_private *dev_priv)
 static inline void intel_gvt_cleanup(struct drm_i915_private *dev_priv)
 {
 }
+static inline bool
+intel_gvt_context_single_port_submit(const struct i915_gem_context *ctx)
+{
+	return false;
+}
 #endif
 
 #endif /* _INTEL_GVT_H_ */
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index dd0e9d587..951540f 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -377,24 +377,6 @@ static void execlists_submit_ports(struct intel_engine_cs *engine)
 	writel(lower_32_bits(desc[0]), elsp);
 }
 
-static bool ctx_single_port_submission(const struct i915_gem_context *ctx)
-{
-	return (IS_ENABLED(CONFIG_DRM_I915_GVT) &&
-		i915_gem_context_force_single_submission(ctx));
-}
-
-static bool can_merge_ctx(const struct i915_gem_context *prev,
-			  const struct i915_gem_context *next)
-{
-	if (prev != next)
-		return false;
-
-	if (ctx_single_port_submission(prev))
-		return false;
-
-	return true;
-}
-
 static void execlists_dequeue(struct intel_engine_cs *engine)
 {
 	struct drm_i915_gem_request *last;
@@ -462,7 +444,8 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
 		 * request, and so we never need to tell the hardware about
 		 * the first.
 		 */
-		if (last && !can_merge_ctx(cursor->ctx, last->ctx)) {
+		if (last && ((last->ctx != cursor->ctx) ||
+			intel_gvt_context_single_port_submit(last->ctx))) {
 			/* If we are on the second port and cannot combine
 			 * this request with the last, then we are done.
 			 */
@@ -475,8 +458,8 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
 			 * context (even though a different request) to
 			 * the second port.
 			 */
-			if (ctx_single_port_submission(last->ctx) ||
-			    ctx_single_port_submission(cursor->ctx))
+			if (intel_gvt_context_single_port_submit(last->ctx) ||
+			    intel_gvt_context_single_port_submit(cursor->ctx))
 				break;
 
 			GEM_BUG_ON(last->ctx == cursor->ctx);
-- 
2.7.4