[Intel-gfx] [PATCH] drm/i915: Remove context pointer from ppgtt struct

[Daniel Vetter]

On Wed, Jul 30, 2014 at 03:21:54PM +0100, Michel Thierry wrote:
> After new vma/ppgtt lifetime rules, the ppgtt can outlive the context
> it was created for.
> 
> - Renamed create_vm_for_ctx to i915_ppgtt_create as ctx/ppgtt are no
> longer referenced.
> - Updated per_file_stats to cope with this change.
> 
> v2: Get the right context for this ppgtt.
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Signed-off-by: Michel Thierry <michel.thierry at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_debugfs.c     | 25 ++++++++++++++++++++++++-
>  drivers/gpu/drm/i915/i915_gem_context.c |  5 ++---
>  drivers/gpu/drm/i915/i915_gem_gtt.h     |  2 --
>  3 files changed, 26 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
> index 9e737b7..0f34d6a 100644
> --- a/drivers/gpu/drm/i915/i915_debugfs.c
> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> @@ -308,6 +308,27 @@ struct file_stats {
>  	size_t active, inactive;
>  };
>  
> +static struct intel_context *
> +i915_get_ppgtt_context(struct drm_i915_file_private *file_priv,
> +		struct i915_hw_ppgtt *ppgtt)
> +{
> +	struct drm_i915_private *dev_priv = file_priv->dev_priv;
> +	struct intel_context *ctx;
> +	struct i915_hw_ppgtt *ctx_ppgtt;
> +
> +	list_for_each_entry(ctx, &dev_priv->context_list, link) {
> +			if (ctx->legacy_hw_ctx.rcs_state == NULL)
> +				continue;
> +			else {
> +				ctx_ppgtt = ctx_to_ppgtt(ctx);

More cans of worms: You can't actually do that because we don't actually
store a ppgtt in ctx->vm, at least not always. That should be replaceable
with a ctx->ppgtt pointer, but there's more.

I think I'll take a look at this myself and do some untangling ...
-Daniel

> +				if (ppgtt == ctx_ppgtt)
> +					return ctx;
> +			}
> +	}
> +
> +	return NULL;
> +}
> +
>  static int per_file_stats(int id, void *ptr, void *data)
>  {
>  	struct drm_i915_gem_object *obj = ptr;
> @@ -322,6 +343,7 @@ static int per_file_stats(int id, void *ptr, void *data)
>  
>  	if (USES_FULL_PPGTT(obj->base.dev)) {
>  		list_for_each_entry(vma, &obj->vma_list, vma_link) {
> +			struct intel_context *ctx;
>  			struct i915_hw_ppgtt *ppgtt;
>  
>  			if (!drm_mm_node_allocated(&vma->node))
> @@ -333,7 +355,8 @@ static int per_file_stats(int id, void *ptr, void *data)
>  			}
>  
>  			ppgtt = container_of(vma->vm, struct i915_hw_ppgtt, base);
> -			if (ppgtt->ctx && ppgtt->ctx->file_priv != stats->file_priv)
> +			ctx = i915_get_ppgtt_context(stats->file_priv, ppgtt);
> +			if (ctx && ctx->file_priv != stats->file_priv)
>  				continue;
>  
>  			if (obj->ring) /* XXX per-vma statistic */
> diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
> index 4cfb03a..0d741f2 100644
> --- a/drivers/gpu/drm/i915/i915_gem_context.c
> +++ b/drivers/gpu/drm/i915/i915_gem_context.c
> @@ -182,7 +182,7 @@ i915_gem_alloc_context_obj(struct drm_device *dev, size_t size)
>  }
>  
>  static struct i915_hw_ppgtt *
> -create_vm_for_ctx(struct drm_device *dev, struct intel_context *ctx)
> +i915_ppgtt_create(struct drm_device *dev)
>  {
>  	struct i915_hw_ppgtt *ppgtt;
>  	int ret;
> @@ -197,7 +197,6 @@ create_vm_for_ctx(struct drm_device *dev, struct intel_context *ctx)
>  		return ERR_PTR(ret);
>  	}
>  
> -	ppgtt->ctx = ctx;
>  	return ppgtt;
>  }
>  
> @@ -287,7 +286,7 @@ i915_gem_create_context(struct drm_device *dev,
>  	}
>  
>  	if (create_vm) {
> -		struct i915_hw_ppgtt *ppgtt = create_vm_for_ctx(dev, ctx);
> +		struct i915_hw_ppgtt *ppgtt = i915_ppgtt_create(dev);
>  
>  		if (IS_ERR_OR_NULL(ppgtt)) {
>  			DRM_DEBUG_DRIVER("PPGTT setup failed (%ld)\n",
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
> index 57d4013..b8806e9 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.h
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
> @@ -258,8 +258,6 @@ struct i915_hw_ppgtt {
>  		dma_addr_t *gen8_pt_dma_addr[4];
>  	};
>  
> -	struct intel_context *ctx;
> -
>  	int (*enable)(struct i915_hw_ppgtt *ppgtt);
>  	int (*switch_mm)(struct i915_hw_ppgtt *ppgtt,
>  			 struct intel_engine_cs *ring,
> -- 
> 2.0.3
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch