Re: [PATCH v3 09/15] drm/gem: Add LRU/shrinker helper

[Dmitry Osipenko]

On 7/26/22 20:50, Rob Clark wrote:
> +/**
> + * drm_gem_lru_move_tail_locked - move the object to the tail of the LRU
> + *
> + * If the object is already in this LRU it will be moved to the
> + * tail.  Otherwise it will be removed from whichever other LRU
> + * it is in (if any) and moved into this LRU.
> + *
> + * Call with LRU lock held.
> + *
> + * @lru: The LRU to move the object into.
> + * @obj: The GEM object to move into this LRU
> + */
> +void
> +drm_gem_lru_move_tail_locked(struct drm_gem_lru *lru, struct drm_gem_object *obj)
> +{
> +	lockdep_assert_held_once(lru->lock);
> +
> +	if (obj->lru)
> +		lru_remove(obj);

The obj->lru also needs to be locked if lru != obj->lru, isn't it? And
then we should add lockdep_assert_held_once(obj->lru->lock).

-- 
Best regards,
Dmitry