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Subject: Re: [PATCH] mm/list_lru.c: remove kvfree_rcu_local()
To:     Shakeel Butt <shakeelb@google.com>,
        Uladzislau Rezki <urezki@gmail.com>,
        "Paul E . McKenney" <paulmck@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org
References: <20210207152148.1285842-1-shakeelb@google.com>
From:   Kirill Tkhai <ktkhai@virtuozzo.com>
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On 07.02.2021 18:21, Shakeel Butt wrote:
> The list_lru file used to have local kvfree_rcu() which was renamed by
> commit e0feed08ab41 ("mm/list_lru.c: Rename kvfree_rcu() to local
> variant") to introduce the globally visible kvfree_rcu(). Now we have
> global kvfree_rcu(), so remove the local kvfree_rcu_local() and just
> use the global one.
> 
> Signed-off-by: Shakeel Butt <shakeelb@google.com>

Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>

> ---
>  mm/list_lru.c | 12 ++----------
>  1 file changed, 2 insertions(+), 10 deletions(-)
> 
> diff --git a/mm/list_lru.c b/mm/list_lru.c
> index fe230081690b..6f067b6b935f 100644
> --- a/mm/list_lru.c
> +++ b/mm/list_lru.c
> @@ -373,21 +373,13 @@ static void memcg_destroy_list_lru_node(struct list_lru_node *nlru)
>  	struct list_lru_memcg *memcg_lrus;
>  	/*
>  	 * This is called when shrinker has already been unregistered,
> -	 * and nobody can use it. So, there is no need to use kvfree_rcu_local().
> +	 * and nobody can use it. So, there is no need to use kvfree_rcu().
>  	 */
>  	memcg_lrus = rcu_dereference_protected(nlru->memcg_lrus, true);
>  	__memcg_destroy_list_lru_node(memcg_lrus, 0, memcg_nr_cache_ids);
>  	kvfree(memcg_lrus);
>  }
>  
> -static void kvfree_rcu_local(struct rcu_head *head)
> -{
> -	struct list_lru_memcg *mlru;
> -
> -	mlru = container_of(head, struct list_lru_memcg, rcu);
> -	kvfree(mlru);
> -}
> -
>  static int memcg_update_list_lru_node(struct list_lru_node *nlru,
>  				      int old_size, int new_size)
>  {
> @@ -419,7 +411,7 @@ static int memcg_update_list_lru_node(struct list_lru_node *nlru,
>  	rcu_assign_pointer(nlru->memcg_lrus, new);
>  	spin_unlock_irq(&nlru->lock);
>  
> -	call_rcu(&old->rcu, kvfree_rcu_local);
> +	kvfree_rcu(old, rcu);
>  	return 0;
>  }
>  
>