[Intel-gfx] [PATCH v2] drm/i915: Push the ring creation flags to the backend

[Chris Wilson]

Push the ring creation flags from the outer GEM context to the inner
intel_cotnext to avoid an unsightly back-reference from inside the
backend.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/gem/i915_gem_context.c   | 16 +++++++++----
 .../gpu/drm/i915/gem/i915_gem_context_types.h |  3 ---
 drivers/gpu/drm/i915/gt/intel_lrc.c           |  5 ++--
 drivers/gpu/drm/i915/i915_debugfs.c           | 23 ++++++++++++-------
 4 files changed, 28 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index 1b3dc7258ef2..809400897322 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -296,6 +296,8 @@ static struct i915_gem_engines *default_engines(struct i915_gem_context *ctx)
 			return ERR_CAST(ce);
 		}
 
+		ce->ring = (void *)SZ_16K;
+
 		e->engines[id] = ce;
 	}
 	e->num_engines = id;
@@ -434,8 +436,6 @@ __create_context(struct drm_i915_private *i915)
 	i915_gem_context_set_bannable(ctx);
 	i915_gem_context_set_recoverable(ctx);
 
-	ctx->ring_size = 4 * PAGE_SIZE;
-
 	for (i = 0; i < ARRAY_SIZE(ctx->hang_timestamp); i++)
 		ctx->hang_timestamp[i] = jiffies - CONTEXT_FAST_HANG_JIFFIES;
 
@@ -565,8 +565,15 @@ i915_gem_context_create_gvt(struct drm_device *dev)
 	i915_gem_context_set_closed(ctx); /* not user accessible */
 	i915_gem_context_clear_bannable(ctx);
 	i915_gem_context_set_force_single_submission(ctx);
-	if (!USES_GUC_SUBMISSION(to_i915(dev)))
-		ctx->ring_size = 512 * PAGE_SIZE; /* Max ring buffer size */
+	if (!USES_GUC_SUBMISSION(to_i915(dev))) {
+		const unsigned long ring_size = 512 * SZ_4K; /* max */
+		struct i915_gem_engines_iter it;
+		struct intel_context *ce;
+
+		for_each_gem_engine(ce, i915_gem_context_lock_engines(ctx), it)
+			ce->ring = (void *)ring_size;
+		i915_gem_context_unlock_engines(ctx);
+	}
 
 	GEM_BUG_ON(i915_gem_context_is_kernel(ctx));
 out:
@@ -605,7 +612,6 @@ i915_gem_context_create_kernel(struct drm_i915_private *i915, int prio)
 
 	i915_gem_context_clear_bannable(ctx);
 	ctx->sched.priority = I915_USER_PRIORITY(prio);
-	ctx->ring_size = PAGE_SIZE;
 
 	GEM_BUG_ON(!i915_gem_context_is_kernel(ctx));
 
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
index a02d98494078..260d59cc3de8 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
@@ -169,9 +169,6 @@ struct i915_gem_context {
 
 	struct i915_sched_attr sched;
 
-	/** ring_size: size for allocating the per-engine ring buffer */
-	u32 ring_size;
-
 	/** guilty_count: How many times this context has caused a GPU hang. */
 	atomic_t guilty_count;
 	/**
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index 5fdac40015cf..3f1b20cc50c2 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -3140,9 +3140,8 @@ static int execlists_context_deferred_alloc(struct intel_context *ce,
 		goto error_deref_obj;
 	}
 
-	ring = intel_engine_create_ring(engine,
-					timeline,
-					ce->gem_context->ring_size);
+	ring = intel_engine_create_ring(engine, timeline,
+					(unsigned long)ce->ring);
 	intel_timeline_put(timeline);
 	if (IS_ERR(ring)) {
 		ret = PTR_ERR(ring);
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 6d3911469801..e237bcecfa1f 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -328,10 +328,14 @@ static void print_context_stats(struct seq_file *m,
 
 		for_each_gem_engine(ce,
 				    i915_gem_context_lock_engines(ctx), it) {
-			if (ce->state)
-				per_file_stats(0, ce->state->obj, &kstats);
-			if (ce->ring)
+			intel_context_lock_pinned(ce);
+			if (intel_context_is_pinned(ce)) {
+				if (ce->state)
+					per_file_stats(0,
+						       ce->state->obj, &kstats);
 				per_file_stats(0, ce->ring->vma->obj, &kstats);
+			}
+			intel_context_unlock_pinned(ce);
 		}
 		i915_gem_context_unlock_engines(ctx);
 
@@ -1677,12 +1681,15 @@ static int i915_context_status(struct seq_file *m, void *unused)
 
 		for_each_gem_engine(ce,
 				    i915_gem_context_lock_engines(ctx), it) {
-			seq_printf(m, "%s: ", ce->engine->name);
-			if (ce->state)
-				describe_obj(m, ce->state->obj);
-			if (ce->ring)
+			intel_context_lock_pinned(ce);
+			if (intel_context_is_pinned(ce)) {
+				seq_printf(m, "%s: ", ce->engine->name);
+				if (ce->state)
+					describe_obj(m, ce->state->obj);
 				describe_ctx_ring(m, ce->ring);
-			seq_putc(m, '\n');
+				seq_putc(m, '\n');
+			}
+			intel_context_unlock_pinned(ce);
 		}
 		i915_gem_context_unlock_engines(ctx);
 
-- 
2.22.0