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Message-ID: <7956e695-3eac-25ef-4412-3a0ff33e3574@fujitsu.com>
Date:   Thu, 6 Jul 2023 19:58:01 +0800
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Subject: Re: [PATCH] memory tier: rename destroy_memory_type() to
 put_memory_type()
To:     Miaohe Lin <linmiaohe@huawei.com>, akpm@linux-foundation.org,
        dan.j.williams@intel.com, vishal.l.verma@intel.com,
        dave.jiang@intel.com
Cc:     ying.huang@intel.com, nvdimm@lists.linux.dev,
        linux-cxl@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
References: <20230706063905.543800-1-linmiaohe@huawei.com>
From:   Xiao Yang <yangx.jy@fujitsu.com>
In-Reply-To: <20230706063905.543800-1-linmiaohe@huawei.com>
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On 2023/7/6 14:39, Miaohe Lin wrote:
> It appears that destroy_memory_type() isn't a very good name because
> we usually will not free the memory_type here. So rename it to a more
> appropriate name i.e. put_memory_type().
> 
> Suggested-by: Huang, Ying <ying.huang@intel.com>
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
>   drivers/dax/kmem.c           | 4 ++--
>   include/linux/memory-tiers.h | 4 ++--
>   mm/memory-tiers.c            | 6 +++---
>   3 files changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c
> index 898ca9505754..c57acb73e3db 100644
> --- a/drivers/dax/kmem.c
> +++ b/drivers/dax/kmem.c
> @@ -264,7 +264,7 @@ static int __init dax_kmem_init(void)
>   	return rc;
>   
>   error_dax_driver:
> -	destroy_memory_type(dax_slowmem_type);
> +	put_memory_type(dax_slowmem_type);
>   err_dax_slowmem_type:
>   	kfree_const(kmem_name);
>   	return rc;
> @@ -275,7 +275,7 @@ static void __exit dax_kmem_exit(void)
>   	dax_driver_unregister(&device_dax_kmem_driver);
>   	if (!any_hotremove_failed)
>   		kfree_const(kmem_name);
> -	destroy_memory_type(dax_slowmem_type);
> +	put_memory_type(dax_slowmem_type);
>   }
>   
>   MODULE_AUTHOR("Intel Corporation");
> diff --git a/include/linux/memory-tiers.h b/include/linux/memory-tiers.h
> index fc9647b1b4f9..437441cdf78f 100644
> --- a/include/linux/memory-tiers.h
> +++ b/include/linux/memory-tiers.h
> @@ -33,7 +33,7 @@ struct memory_dev_type {
>   #ifdef CONFIG_NUMA
>   extern bool numa_demotion_enabled;
>   struct memory_dev_type *alloc_memory_type(int adistance);
> -void destroy_memory_type(struct memory_dev_type *memtype);
> +void put_memory_type(struct memory_dev_type *memtype);
>   void init_node_memory_type(int node, struct memory_dev_type *default_type);
>   void clear_node_memory_type(int node, struct memory_dev_type *memtype);
>   #ifdef CONFIG_MIGRATION
> @@ -68,7 +68,7 @@ static inline struct memory_dev_type *alloc_memory_type(int adistance)
>   	return NULL;
>   }
>   
> -static inline void destroy_memory_type(struct memory_dev_type *memtype)
> +static inline void put_memory_type(struct memory_dev_type *memtype)
>   {
>   
>   }
> diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c
> index 1719fa3bcf02..c49ab03f49b1 100644
> --- a/mm/memory-tiers.c
> +++ b/mm/memory-tiers.c
> @@ -560,11 +560,11 @@ struct memory_dev_type *alloc_memory_type(int adistance)
>   }
>   EXPORT_SYMBOL_GPL(alloc_memory_type);
>   
> -void destroy_memory_type(struct memory_dev_type *memtype)
> +void put_memory_type(struct memory_dev_type *memtype)
>   {
>   	kref_put(&memtype->kref, release_memtype);
>   }
> -EXPORT_SYMBOL_GPL(destroy_memory_type);
> +EXPORT_SYMBOL_GPL(put_memory_type);
>   
>   void init_node_memory_type(int node, struct memory_dev_type *memtype)
>   {
> @@ -586,7 +586,7 @@ void clear_node_memory_type(int node, struct memory_dev_type *memtype)
>   	 */
>   	if (!node_memory_types[node].map_count) {
>   		node_memory_types[node].memtype = NULL;
> -		destroy_memory_type(memtype);
> +		put_memory_type(memtype);
Hi Maohe,

I didn't find that destroy_memory_type(memtype) is called here on 
mainline kernel. Did I miss something?

Other than that, it looks good to me.
Reviewed-by: Xiao Yang <yangx.jy@fujitsu.com>

Best Regards,
Xiao Yang

>   	}
>   	mutex_unlock(&memory_tier_lock);
>   }