Re: [PATCH 08/29] drm/i915: Introduce drm_i915_gem_object_ops

[Daniel Vetter <daniel@ffwll.ch>]

On Sat, Aug 11, 2012 at 03:41:07PM +0100, Chris Wilson wrote:
> In order to specialise functions depending upon the type of object, we
> can attach vfuncs to each object via their obj->driver_private pointer,
> bringing it back to life!
> 
> For instance, this will be used in future patches to only bind pages from
> a dma-buf for the duration that the object is used by the GPU - and so
> prevent them from pinning those pages for the entire of the object.

Tbh I'd prefer adding a pointer with the right type over not wasting that
untyped pointer ... Otherwise I like this, and I'll follow up with
suggestions for other functions we could add when reviewing the other
patches ;-)
-Daniel

> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>  drivers/gpu/drm/i915/i915_drv.h        |   10 ++++-
>  drivers/gpu/drm/i915/i915_gem.c        |   65 ++++++++++++++++++++++----------
>  drivers/gpu/drm/i915/i915_gem_dmabuf.c |    4 +-
>  3 files changed, 56 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index bbc51ef..c42190b 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -895,6 +895,11 @@ enum i915_cache_level {
>  	I915_CACHE_LLC_MLC, /* gen6+, in docs at least! */
>  };
>  
> +struct drm_i915_gem_object_ops {
> +	int (*get_pages)(struct drm_i915_gem_object *);
> +	void (*put_pages)(struct drm_i915_gem_object *);
> +};
> +
>  struct drm_i915_gem_object {
>  	struct drm_gem_object base;
>  
> @@ -1302,7 +1307,8 @@ int i915_gem_wait_ioctl(struct drm_device *dev, void *data,
>  			struct drm_file *file_priv);
>  void i915_gem_load(struct drm_device *dev);
>  int i915_gem_init_object(struct drm_gem_object *obj);
> -void i915_gem_object_init(struct drm_i915_gem_object *obj);
> +void i915_gem_object_init(struct drm_i915_gem_object *obj,
> +			 const struct drm_i915_gem_object_ops *ops);
>  struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev,
>  						  size_t size);
>  void i915_gem_free_object(struct drm_gem_object *obj);
> @@ -1315,7 +1321,7 @@ int __must_check i915_gem_object_unbind(struct drm_i915_gem_object *obj);
>  void i915_gem_release_mmap(struct drm_i915_gem_object *obj);
>  void i915_gem_lastclose(struct drm_device *dev);
>  
> -int __must_check i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj);
> +int __must_check i915_gem_object_get_pages(struct drm_i915_gem_object *obj);
>  int __must_check i915_mutex_lock_interruptible(struct drm_device *dev);
>  int i915_gem_object_sync(struct drm_i915_gem_object *obj,
>  			 struct intel_ring_buffer *to);
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 9c8787e..ed6a1ec 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -1407,15 +1407,12 @@ i915_gem_object_is_purgeable(struct drm_i915_gem_object *obj)
>  	return obj->madv == I915_MADV_DONTNEED;
>  }
>  
> -static int
> +static void
>  i915_gem_object_put_pages_gtt(struct drm_i915_gem_object *obj)
>  {
>  	int page_count = obj->base.size / PAGE_SIZE;
>  	int ret, i;
>  
> -	if (obj->pages == NULL)
> -		return 0;
> -
>  	BUG_ON(obj->gtt_space);
>  	BUG_ON(obj->madv == __I915_MADV_PURGED);
>  
> @@ -1448,9 +1445,19 @@ i915_gem_object_put_pages_gtt(struct drm_i915_gem_object *obj)
>  
>  	drm_free_large(obj->pages);
>  	obj->pages = NULL;
> +}
>  
> -	list_del(&obj->gtt_list);
> +static int
> +i915_gem_object_put_pages(struct drm_i915_gem_object *obj)
> +{
> +	const struct drm_i915_gem_object_ops *ops = obj->base.driver_private;
>  
> +	if (obj->sg_table || obj->pages == NULL)
> +		return 0;
> +
> +	ops->put_pages(obj);
> +
> +	list_del(&obj->gtt_list);
>  	if (i915_gem_object_is_purgeable(obj))
>  		i915_gem_object_truncate(obj);
>  
> @@ -1467,7 +1474,7 @@ i915_gem_purge(struct drm_i915_private *dev_priv, long target)
>  				 &dev_priv->mm.unbound_list,
>  				 gtt_list) {
>  		if (i915_gem_object_is_purgeable(obj) &&
> -		    i915_gem_object_put_pages_gtt(obj) == 0) {
> +		    i915_gem_object_put_pages(obj) == 0) {
>  			count += obj->base.size >> PAGE_SHIFT;
>  			if (count >= target)
>  				return count;
> @@ -1479,7 +1486,7 @@ i915_gem_purge(struct drm_i915_private *dev_priv, long target)
>  				 mm_list) {
>  		if (i915_gem_object_is_purgeable(obj) &&
>  		    i915_gem_object_unbind(obj) == 0 &&
> -		    i915_gem_object_put_pages_gtt(obj) == 0) {
> +		    i915_gem_object_put_pages(obj) == 0) {
>  			count += obj->base.size >> PAGE_SHIFT;
>  			if (count >= target)
>  				return count;
> @@ -1497,10 +1504,10 @@ i915_gem_shrink_all(struct drm_i915_private *dev_priv)
>  	i915_gem_evict_everything(dev_priv->dev);
>  
>  	list_for_each_entry_safe(obj, next, &dev_priv->mm.unbound_list, gtt_list)
> -		i915_gem_object_put_pages_gtt(obj);
> +		i915_gem_object_put_pages(obj);
>  }
>  
> -int
> +static int
>  i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj)
>  {
>  	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
> @@ -1509,9 +1516,6 @@ i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj)
>  	struct page *page;
>  	gfp_t gfp;
>  
> -	if (obj->pages || obj->sg_table)
> -		return 0;
> -
>  	/* Assert that the object is not currently in any GPU domain. As it
>  	 * wasn't in the GTT, there shouldn't be any way it could have been in
>  	 * a GPU cache
> @@ -1561,7 +1565,6 @@ i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj)
>  	if (i915_gem_object_needs_bit17_swizzle(obj))
>  		i915_gem_object_do_bit_17_swizzle(obj);
>  
> -	list_add_tail(&obj->gtt_list, &dev_priv->mm.unbound_list);
>  	return 0;
>  
>  err_pages:
> @@ -1573,6 +1576,24 @@ err_pages:
>  	return PTR_ERR(page);
>  }
>  
> +int
> +i915_gem_object_get_pages(struct drm_i915_gem_object *obj)
> +{
> +	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
> +	const struct drm_i915_gem_object_ops *ops = obj->base.driver_private;
> +	int ret;
> +
> +	if (obj->sg_table || obj->pages)
> +		return 0;
> +
> +	ret = ops->get_pages(obj);
> +	if (ret)
> +		return ret;
> +
> +	list_add_tail(&obj->gtt_list, &dev_priv->mm.unbound_list);
> +	return 0;
> +}
> +
>  void
>  i915_gem_object_move_to_active(struct drm_i915_gem_object *obj,
>  			       struct intel_ring_buffer *ring,
> @@ -1828,7 +1849,7 @@ void i915_gem_reset(struct drm_device *dev)
>  
>  
>  	list_for_each_entry_safe(obj, next, &dev_priv->mm.unbound_list, gtt_list)
> -		i915_gem_object_put_pages_gtt(obj);
> +		i915_gem_object_put_pages(obj);
>  
>  	/* The fence registers are invalidated so clear them out */
>  	i915_gem_reset_fences(dev);
> @@ -2818,7 +2839,7 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
>  		return -E2BIG;
>  	}
>  
> -	ret = i915_gem_object_get_pages_gtt(obj);
> +	ret = i915_gem_object_get_pages(obj);
>  	if (ret)
>  		return ret;
>  
> @@ -3557,9 +3578,10 @@ unlock:
>  	return ret;
>  }
>  
> -void i915_gem_object_init(struct drm_i915_gem_object *obj)
> +void i915_gem_object_init(struct drm_i915_gem_object *obj,
> +			  const struct drm_i915_gem_object_ops *ops)
>  {
> -	obj->base.driver_private = NULL;
> +	obj->base.driver_private = (void *)ops;
>  
>  	INIT_LIST_HEAD(&obj->mm_list);
>  	INIT_LIST_HEAD(&obj->gtt_list);
> @@ -3574,6 +3596,11 @@ void i915_gem_object_init(struct drm_i915_gem_object *obj)
>  	i915_gem_info_add_obj(obj->base.dev->dev_private, obj->base.size);
>  }
>  
> +static const struct drm_i915_gem_object_ops i915_gem_object_ops = {
> +	.get_pages = i915_gem_object_get_pages_gtt,
> +	.put_pages = i915_gem_object_put_pages_gtt,
> +};
> +
>  struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev,
>  						  size_t size)
>  {
> @@ -3600,7 +3627,7 @@ struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev,
>  	mapping = obj->base.filp->f_path.dentry->d_inode->i_mapping;
>  	mapping_set_gfp_mask(mapping, mask);
>  
> -	i915_gem_object_init(obj);
> +	i915_gem_object_init(obj, &i915_gem_object_ops);
>  
>  	obj->base.write_domain = I915_GEM_DOMAIN_CPU;
>  	obj->base.read_domains = I915_GEM_DOMAIN_CPU;
> @@ -3658,7 +3685,7 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
>  		dev_priv->mm.interruptible = was_interruptible;
>  	}
>  
> -	i915_gem_object_put_pages_gtt(obj);
> +	i915_gem_object_put_pages(obj);
>  	i915_gem_object_free_mmap_offset(obj);
>  
>  	drm_gem_object_release(&obj->base);
> diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> index e5f0375..1203460 100644
> --- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> +++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> @@ -41,7 +41,7 @@ static struct sg_table *i915_gem_map_dma_buf(struct dma_buf_attachment *attachme
>  	if (ret)
>  		return ERR_PTR(ret);
>  
> -	ret = i915_gem_object_get_pages_gtt(obj);
> +	ret = i915_gem_object_get_pages(obj);
>  	if (ret) {
>  		sg = ERR_PTR(ret);
>  		goto out;
> @@ -89,7 +89,7 @@ static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
>  		goto out_unlock;
>  	}
>  
> -	ret = i915_gem_object_get_pages_gtt(obj);
> +	ret = i915_gem_object_get_pages(obj);
>  	if (ret) {
>  		mutex_unlock(&dev->struct_mutex);
>  		return ERR_PTR(ret);
> -- 
> 1.7.10.4
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Daniel Vetter
Mail: daniel@ffwll.ch
Mobile: +41 (0)79 365 57 48