[Intel-gfx] [RFCv2 06/14] drm/i915: let __i915_gem_context_create() takes context creation params

[Zhi Wang]

Let the core logic of context creation service creats the GEM context by
context creation params.

Now it provides following options for context creation:
- Need to create legacy context for this GEM context?
- Need to create PPGTT instance for this GEM context?
- Need to treat this context as the global default context?

And for all the assumptions in the original implementation, we keep them
in the upper-level wrapper.

Signed-off-by: Zhi Wang <zhi.a.wang at intel.com>
---
 drivers/gpu/drm/i915/i915_gem_context.c | 71 ++++++++++++++++++++-------------
 1 file changed, 43 insertions(+), 28 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 5516346..cda09f7 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -223,6 +223,13 @@ static int __create_legacy_hw_context(struct drm_device *dev,
 	return 0;
 }
 
+struct i915_gem_context_create_params {
+	struct drm_i915_file_private *file_priv;
+	bool has_legacy_ctx;
+	bool has_ppgtt;
+	bool is_default_ctx;
+};
+
 static struct intel_context *
 __create_hw_context(struct drm_device *dev,
 		    struct drm_i915_file_private *file_priv)
@@ -249,44 +256,43 @@ __create_hw_context(struct drm_device *dev,
 
 static struct intel_context *
 __i915_gem_create_context(struct drm_device *dev,
-			struct drm_i915_file_private *file_priv)
+			struct i915_gem_context_create_params *params)
 {
-	struct drm_i915_private *dev_priv = to_i915(dev);
-	const bool is_global_default_ctx = file_priv == NULL;
-	const bool is_legacy_ctx = !!dev_priv->hw_context_size;
 	struct intel_context *ctx;
 	int ret = 0;
 
 	BUG_ON(!mutex_is_locked(&dev->struct_mutex));
 
-	ctx = __create_hw_context(dev, file_priv);
+	ctx = __create_hw_context(dev, params->file_priv);
 	if (IS_ERR(ctx))
 		return ctx;
 
-	if (is_legacy_ctx) {
+	if (params->has_legacy_ctx) {
 		ret = __create_legacy_hw_context(dev, ctx);
 		if (ret)
 			goto err_destroy;
-	}
 
-	if (is_global_default_ctx && is_legacy_ctx) {
-		/* We may need to do things with the shrinker which
-		 * require us to immediately switch back to the default
-		 * context. This can cause a problem as pinning the
-		 * default context also requires GTT space which may not
-		 * be available. To avoid this we always pin the default
-		 * context.
-		 */
-		ret = i915_gem_obj_ggtt_pin(ctx->legacy_hw_ctx.rcs_state,
-					    get_context_alignment(dev), 0);
-		if (ret) {
-			DRM_DEBUG_DRIVER("Couldn't pin %d\n", ret);
-			goto err_destroy;
+		if (params->is_default_ctx) {
+			/* We may need to do things with the shrinker
+			 * which require us to immediately switch back to
+			 * the default context. This can cause a problem as
+			 * pinning the default context also requires GTT
+			 * space which may not be available. To avoid this
+			 * we always pin the default context.
+			 */
+			ret = i915_gem_obj_ggtt_pin(
+					ctx->legacy_hw_ctx.rcs_state,
+					get_context_alignment(dev), 0);
+			if (ret) {
+				DRM_DEBUG_DRIVER("Couldn't pin %d\n", ret);
+				goto err_destroy;
+			}
 		}
 	}
 
-	if (USES_FULL_PPGTT(dev)) {
-		struct i915_hw_ppgtt *ppgtt = i915_ppgtt_create(dev, file_priv);
+	if (params->has_ppgtt) {
+		struct i915_hw_ppgtt *ppgtt = i915_ppgtt_create(dev,
+			params->file_priv);
 
 		if (IS_ERR_OR_NULL(ppgtt)) {
 			DRM_DEBUG_DRIVER("PPGTT setup failed (%ld)\n",
@@ -303,7 +309,7 @@ __i915_gem_create_context(struct drm_device *dev,
 	return ctx;
 
 err_unpin:
-	if (is_global_default_ctx && is_legacy_ctx)
+	if (params->is_default_ctx && params->has_legacy_ctx)
 		i915_gem_object_ggtt_unpin(ctx->legacy_hw_ctx.rcs_state);
 err_destroy:
 	i915_gem_context_unreference(ctx);
@@ -311,12 +317,12 @@ err_destroy:
 }
 
 static inline int alloc_context_idr(struct drm_device *dev,
-	struct intel_context *ctx)
+	struct intel_context *ctx,
+	struct i915_gem_context_create_params *params)
 {
 	int ret;
 
-	/* Default context will never have a file_priv */
-	if (ctx->file_priv != NULL) {
+	if (params->is_default_ctx) {
 		ret = idr_alloc(&ctx->file_priv->context_idr, ctx,
 				DEFAULT_CONTEXT_HANDLE, 0, GFP_KERNEL);
 		if (ret < 0)
@@ -338,14 +344,23 @@ static struct intel_context *
 i915_gem_create_context(struct drm_device *dev,
 		struct drm_i915_file_private *file_priv)
 {
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_gem_context_create_params params;
 	struct intel_context *ctx;
 	int ret;
 
-	ctx = __i915_gem_create_context(dev, file_priv);
+	memset(&params, 0, sizeof(params));
+
+	params.file_priv = file_priv;
+	params.has_legacy_ctx = !!dev_priv->hw_context_size;
+	params.has_ppgtt = USES_FULL_PPGTT(dev);
+	params.is_default_ctx = (file_priv == NULL);
+
+	ctx = __i915_gem_create_context(dev, &params);
 	if (IS_ERR(ctx))
 		return ctx;
 
-	ret = alloc_context_idr(dev, ctx);
+	ret = alloc_context_idr(dev, ctx, &params);
 	if (ret < 0) {
 		i915_gem_context_unreference(ctx);
 		return ERR_PTR(ret);
-- 
1.9.1