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Message-ID: <3c899066-d85d-3bd7-5b13-d5228b7aeb93@suse.cz>
Date:   Wed, 15 Jun 2022 09:26:13 +0200
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Subject: Re: [PATCH] mm/slub: Simplify __kmem_cache_alias()
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To:     sxwjean@me.com, cl@linux.com, penberg@kernel.org,
        rientjes@google.com, iamjoonsoo.kim@lge.com,
        akpm@linux-foundation.org, roman.gushchin@linux.dev,
        42.hyeyoo@gmail.com
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Xiongwei Song <xiongwei.song@windriver.com>
References: <20220531005550.10613-1-sxwjean@me.com>
From:   Vlastimil Babka <vbabka@suse.cz>
In-Reply-To: <20220531005550.10613-1-sxwjean@me.com>
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On 5/31/22 02:55, sxwjean@me.com wrote:
> From: Xiongwei Song <xiongwei.song@windriver.com>
> 
> There is no need to do anything if sysfs_slab_alias() return nonzero
> value after getting a mergeable cache.
> 
> Signed-off-by: Xiongwei Song <xiongwei.song@windriver.com>

Thanks, added to slab/for-5.20/cleanup

> ---
>  mm/slub.c | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/mm/slub.c b/mm/slub.c
> index d8d5abf49f5f..9444277d669a 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -4861,6 +4861,9 @@ __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
>  
>  	s = find_mergeable(size, align, flags, name, ctor);
>  	if (s) {
> +		if (sysfs_slab_alias(s, name))
> +			return NULL;
> +
>  		s->refcount++;
>  
>  		/*
> @@ -4869,11 +4872,6 @@ __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
>  		 */
>  		s->object_size = max(s->object_size, size);
>  		s->inuse = max(s->inuse, ALIGN(size, sizeof(void *)));
> -
> -		if (sysfs_slab_alias(s, name)) {
> -			s->refcount--;
> -			s = NULL;
> -		}
>  	}
>  
>  	return s;