[Intel-gfx] [PATCH] drm/i915: Retire an active batch pool object rather than allocate new

[Mika Kuoppala]

Chris Wilson <chris at chris-wilson.co.uk> writes:

> Since obj->active_count is only updated upon retirement, if we see an
> active object in the batch pool, double check that is still active
> before deciding to allocate a new object.
>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>  drivers/gpu/drm/i915/i915_gem_batch_pool.c | 29 ++++++++++++++---------------
>  1 file changed, 14 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_gem_batch_pool.c b/drivers/gpu/drm/i915/i915_gem_batch_pool.c
> index 853b615fa574..22b7ee2c9ef6 100644
> --- a/drivers/gpu/drm/i915/i915_gem_batch_pool.c
> +++ b/drivers/gpu/drm/i915/i915_gem_batch_pool.c
> @@ -96,8 +96,7 @@ struct drm_i915_gem_object *
>  i915_gem_batch_pool_get(struct i915_gem_batch_pool *pool,
>  			size_t size)
>  {
> -	struct drm_i915_gem_object *obj = NULL;
> -	struct drm_i915_gem_object *tmp;
> +	struct drm_i915_gem_object *obj;
>  	struct list_head *list;
>  	int n, ret;
>  
> @@ -112,26 +111,26 @@ i915_gem_batch_pool_get(struct i915_gem_batch_pool *pool,
>  		n = ARRAY_SIZE(pool->cache_list) - 1;
>  	list = &pool->cache_list[n];
>  
> -	list_for_each_entry(tmp, list, batch_pool_link) {
> +	list_for_each_entry(obj, list, batch_pool_link) {
>  		/* The batches are strictly LRU ordered */
> -		if (i915_gem_object_is_active(tmp))
> -			break;
> +		if (i915_gem_object_is_active(obj)) {
> +			i915_gem_retire_requests(pool->engine->i915);
> +			if (i915_gem_object_is_active(obj))
> +				break;
> +		}
>  
> -		GEM_BUG_ON(!reservation_object_test_signaled_rcu(tmp->resv,
> +		GEM_BUG_ON(!reservation_object_test_signaled_rcu(obj->resv,
>  								 true));
>  
> -		if (tmp->base.size >= size) {
> -			obj = tmp;

This chunk here collides with the
d07f0e59b ("drm/i915: Move GEM activity tracking..")

Please rebase.

-Mika


> -			break;
> -		}
> +		if (obj->base.size >= size)
> +			goto found;
>  	}
>  
> -	if (obj == NULL) {
> -		obj = i915_gem_object_create_internal(pool->engine->i915, size);
> -		if (IS_ERR(obj))
> -			return obj;
> -	}
> +	obj = i915_gem_object_create_internal(pool->engine->i915, size);
> +	if (IS_ERR(obj))
> +		return obj;
>  
> +found:
>  	ret = i915_gem_object_pin_pages(obj);
>  	if (ret)
>  		return ERR_PTR(ret);
> -- 
> 2.11.0
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx