[PATCH 4/7] drm/i915: A bit better messaging for contexts

[ben at bwidawsk.net (Ben Widawsky)]

Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_gem_context.c | 24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 8e218ad..5ac93f4 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -97,6 +97,11 @@
 
 static int do_switch(struct i915_hw_context *to);
 
+static inline bool is_default_context(struct i915_hw_context *ctx)
+{
+	return (ctx == ctx->ring->default_context);
+}
+
 static int get_context_size(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -124,8 +129,10 @@ static int get_context_size(struct drm_device *dev)
 
 static void do_destroy(struct i915_hw_context *ctx)
 {
-	if (ctx->file_priv)
+	if (ctx->file_priv) {
+		WARN_ON(!is_default_context(ctx));
 		idr_remove(&ctx->file_priv->context_idr, ctx->id);
+	}
 
 	drm_gem_object_unreference(&ctx->obj->base);
 	kfree(ctx);
@@ -177,11 +184,6 @@ err_out:
 	return ERR_PTR(ret);
 }
 
-static inline bool is_default_context(struct i915_hw_context *ctx)
-{
-	return (ctx == ctx->ring->default_context);
-}
-
 /**
  * The default context needs to exist per ring that uses contexts. It stores the
  * context state of the GPU for applications that don't utilize HW contexts, as
@@ -213,7 +215,7 @@ static int create_default_context(struct drm_i915_private *dev_priv)
 	if (ret)
 		goto err_unpin;
 
-	DRM_DEBUG_DRIVER("Default HW context loaded\n");
+	DRM_DEBUG_DRIVER("Default HW context loaded (%p)\n", ctx);
 	return 0;
 
 err_unpin:
@@ -275,6 +277,7 @@ static int context_idr_cleanup(int id, void *p, void *data)
 
 	BUG_ON(id == DEFAULT_CONTEXT_ID);
 
+	DRM_DEBUG_DRIVER("Context %d closed before destroy.\n", ctx->id);
 	do_destroy(ctx);
 
 	return 0;
@@ -453,8 +456,11 @@ int i915_switch_context(struct intel_ring_buffer *ring,
 		return -EINVAL;
 
 	to = i915_gem_context_get(ring, file->driver_priv, to_id);
-	if (to == NULL)
+	if (unlikely(!to)) {
+		BUG_ON(to_id == DEFAULT_CONTEXT_ID);
+		DRM_DEBUG_DRIVER("Couldn't find context %d\n", to_id);
 		return -ENOENT;
+	}
 
 	return do_switch(to);
 }
@@ -517,6 +523,6 @@ int i915_gem_context_destroy_ioctl(struct drm_device *dev, void *data,
 
 	mutex_unlock(&dev->struct_mutex);
 
-	DRM_DEBUG_DRIVER("HW context %d destroyed\n", args->ctx_id);
+	DRM_DEBUG_DRIVER("User destroyed context %d\n", args->ctx_id);
 	return 0;
 }
-- 
1.8.2