[Intel-gfx] [PATCH v2 2/4] drm/i915: Update domain tracking for GEM objects on hibernation

[Joonas Lahtinen]

On to, 2016-05-12 at 15:28 +0100, Chris Wilson wrote:
> When creating the hibernation image, the CPU will read the pages of all
> objects and thus conflict with our domain tracking. We need to update
> our domain tracking to accurately reflect the state on restoration.
> 
> v2: Perform the domain tracking inside freeze, before the image is
> written, rather than upon restoration.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Imre Deak <imre.deak at intel.com>
> Cc: David Weinehall <david.weinehall at intel.com>

Reviewed-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>

> ---
>  drivers/gpu/drm/i915/i915_drv.c | 12 +++++++++++-
>  drivers/gpu/drm/i915/i915_drv.h |  2 ++
>  drivers/gpu/drm/i915/i915_gem.c | 28 ++++++++++++++++++++++++++++
>  3 files changed, 41 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 6a2e7f84276b..dba03c026151 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -1123,7 +1123,17 @@ static int i915_pm_freeze(struct device *dev)
>  
>  static int i915_pm_freeze_late(struct device *dev)
>  {
> -	return i915_pm_suspend_late(dev);
> +	int ret;
> +
> +	ret = i915_pm_suspend_late(dev);
> +	if (ret)
> +		return ret;
> +
> +	ret = i915_gem_freeze_late(dev_to_i915(dev));
> +	if (ret)
> +		return ret;
> +
> +	return 0;
>  }
>  
>  /* thaw: called after creating the hibernation image, but before turning off. */
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 7a0b51301337..0a4255fa8895 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -2961,6 +2961,8 @@ int i915_gem_wait_ioctl(struct drm_device *dev, void *data,
>  void i915_gem_load_init(struct drm_device *dev);
>  void i915_gem_load_cleanup(struct drm_device *dev);
>  void i915_gem_load_init_fences(struct drm_i915_private *dev_priv);
> +int i915_gem_freeze_late(struct drm_i915_private *dev_priv);
> +
>  void *i915_gem_object_alloc(struct drm_device *dev);
>  void i915_gem_object_free(struct drm_i915_gem_object *obj);
>  void i915_gem_object_init(struct drm_i915_gem_object *obj,
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index be75689455b2..7bd670e34ee5 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -5053,6 +5053,34 @@ void i915_gem_load_cleanup(struct drm_device *dev)
>  	kmem_cache_destroy(dev_priv->objects);
>  }
>  
> +int i915_gem_freeze_late(struct drm_i915_private *dev_priv)
> +{
> +	struct drm_i915_gem_object *obj;
> +
> +	/* Called just before we write the hibernation image.
> +	 *
> +	 * We need to update the domain tracking to reflect that the CPU
> +	 * will be accessing all the pages to create and restore from the
> +	 * hibernation, and so upon restoration those pages will be in the
> +	 * CPU domain.
> +	 *
> +	 * To make sure the hibernation image contains the latest state,
> +	 * we update that state just before writing out the image.
> +	 */
> +
> +	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list) {
> +		obj->base.read_domains = I915_GEM_DOMAIN_CPU;
> +		obj->base.write_domain = I915_GEM_DOMAIN_CPU;
> +	}
> +
> +	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
> +		obj->base.read_domains = I915_GEM_DOMAIN_CPU;
> +		obj->base.write_domain = I915_GEM_DOMAIN_CPU;
> +	}
> +
> +	return 0;
> +}
> +
>  void i915_gem_release(struct drm_device *dev, struct drm_file *file)
>  {
>  	struct drm_i915_file_private *file_priv = file->driver_priv;
-- 
Joonas Lahtinen
Open Source Technology Center
Intel Corporation