[Intel-gfx] [PATCH] drm/i915: Store preemption capability in engine->flags

[Chris Wilson]

Let's avoid having to delve down the pointer chain to see if the i915
device has support for preemption and store that on the engine, which
made the decision in the first place!

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Tomasz Lis <tomasz.lis at intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
Cc: Michał Winiarski <michal.winiarski at intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
---
 drivers/gpu/drm/i915/intel_lrc.c        |  7 +++++--
 drivers/gpu/drm/i915/intel_ringbuffer.h | 13 +++++++++++--
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index f60b61bf8b3b..48073987214f 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -183,7 +183,8 @@ static inline bool need_preempt(const struct intel_engine_cs *engine,
 				const struct i915_request *last,
 				int prio)
 {
-	return engine->i915->preempt_context && prio > max(rq_prio(last), 0);
+	return (intel_engine_has_preemption(engine) &&
+		prio > max(rq_prio(last), 0));
 }
 
 /**
@@ -2089,11 +2090,13 @@ static void execlists_set_default_submission(struct intel_engine_cs *engine)
 	engine->unpark = NULL;
 
 	engine->flags |= I915_ENGINE_SUPPORTS_STATS;
+	if (engine->i915->preempt_context)
+		engine->flags |= I915_ENGINE_HAS_PREEMPTION;
 
 	engine->i915->caps.scheduler =
 		I915_SCHEDULER_CAP_ENABLED |
 		I915_SCHEDULER_CAP_PRIORITY;
-	if (engine->i915->preempt_context)
+	if (intel_engine_has_preemption(engine))
 		engine->i915->caps.scheduler |= I915_SCHEDULER_CAP_PREEMPTION;
 }
 
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index a02c7b3b9d55..1079254e6b89 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -562,6 +562,7 @@ struct intel_engine_cs {
 
 #define I915_ENGINE_NEEDS_CMD_PARSER BIT(0)
 #define I915_ENGINE_SUPPORTS_STATS   BIT(1)
+#define I915_ENGINE_HAS_PREEMPTION   BIT(2)
 	unsigned int flags;
 
 	/*
@@ -621,16 +622,24 @@ struct intel_engine_cs {
 	} stats;
 };
 
-static inline bool intel_engine_needs_cmd_parser(struct intel_engine_cs *engine)
+static inline bool
+intel_engine_needs_cmd_parser(const struct intel_engine_cs *engine)
 {
 	return engine->flags & I915_ENGINE_NEEDS_CMD_PARSER;
 }
 
-static inline bool intel_engine_supports_stats(struct intel_engine_cs *engine)
+static inline bool
+intel_engine_supports_stats(const struct intel_engine_cs *engine)
 {
 	return engine->flags & I915_ENGINE_SUPPORTS_STATS;
 }
 
+static inline bool
+intel_engine_has_preemption(const struct intel_engine_cs *engine)
+{
+	return engine->flags & I915_ENGINE_HAS_PREEMPTION;
+}
+
 static inline void
 execlists_set_active(struct intel_engine_execlists *execlists,
 		     unsigned int bit)
-- 
2.16.3