drm/i915: Move priolist to new i915_sched_engine object

Introduce i915_sched_engine object which is lower level data structure
that i915_scheduler / generic code can operate on without touching
execlist specific structures. This allows additional submission backends
to be added without breaking the layering. Currently the execlists
backend uses 1 of these object per each engine (physical or virtual) but
future backends like the GuC will point to less instances utilizing the
reference counting.

This is a bit of detour to integrating the i915 with the DRM scheduler
but this object will still exist when the DRM scheduler lands in the
i915. It will however look a bit different. It will encapsulate the
drm_gpu_scheduler object plus and common variables (to the backends)
related to scheduling. Regardless this is a step in the right direction.

This patch starts the aforementioned transition by moving the priolist
into the i915_sched_engine object.

v3:
 (Jason Ekstrand)
  Update comment next to intel_engine_cs.virtual
  Add kernel doc
 (Checkpatch)
  Fix double the in commit message
v4:
 (Daniele)
  Update comment message.
  Add comment about subclass field

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210618010638.98941-2-matthew.brost@intel.com

1 files changed, 8 insertions, 1 deletions

diff --git a/drivers/gpu/drm/i915/gt/mock_engine.c b/drivers/gpu/drm/i915/gt/mock_engine.c
index 32589c6625e1..b1fdba13e900 100644
--- a/drivers/gpu/drm/i915/gt/mock_engine.c
+++ b/drivers/gpu/drm/i915/gt/mock_engine.c
@@ -283,6 +283,7 @@ static void mock_engine_release(struct intel_engine_cs *engine)
 
 	GEM_BUG_ON(timer_pending(&mock->hw_delay));
 
+	i915_sched_engine_put(engine->sched_engine);
 	intel_breadcrumbs_free(engine->breadcrumbs);
 
 	intel_context_unpin(engine->kernel_context);
@@ -345,6 +346,10 @@ int mock_engine_init(struct intel_engine_cs *engine)
 {
 	struct intel_context *ce;
 
+	engine->sched_engine = i915_sched_engine_create(ENGINE_MOCK);
+	if (!engine->sched_engine)
+		return -ENOMEM;
+
 	intel_engine_init_active(engine, ENGINE_MOCK);
 	intel_engine_init_execlists(engine);
 	intel_engine_init__pm(engine);
@@ -352,7 +357,7 @@ int mock_engine_init(struct intel_engine_cs *engine)
 
 	engine->breadcrumbs = intel_breadcrumbs_create(NULL);
 	if (!engine->breadcrumbs)
-		return -ENOMEM;
+		goto err_schedule;
 
 	ce = create_kernel_context(engine);
 	if (IS_ERR(ce))
@@ -366,6 +371,8 @@ int mock_engine_init(struct intel_engine_cs *engine)
 
 err_breadcrumbs:
 	intel_breadcrumbs_free(engine->breadcrumbs);
+err_schedule:
+	i915_sched_engine_put(engine->sched_engine);
 	return -ENOMEM;
 }