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Date:   Thu, 9 Nov 2023 14:05:42 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Jeff Xie <jeff.xie@linux.dev>
Cc:     akpm@linux-foundation.org, iamjoonsoo.kim@lge.com, vbabka@suse.cz,
        cl@linux.com, penberg@kernel.org, rientjes@google.com,
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        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        chensong_2000@189.cn, xiehuan09@gmail.com
Subject: Re: [RFC][PATCH 2/4] mm, slub: implement slub allocate post callback
 for page_owner
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References: <20231109032521.392217-1-jeff.xie@linux.dev>
 <20231109032521.392217-3-jeff.xie@linux.dev>
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On Thu, Nov 09, 2023 at 11:25:19AM +0800, Jeff Xie wrote:
> +#ifdef CONFIG_PAGE_OWNER
> +static int slab_alloc_post_page_owner(struct folio *folio, struct task_struct *tsk,
> +			void *data, char *kbuf, size_t count)
> +{
> +	int ret;
> +	struct kmem_cache *kmem_cache = data;
> +
> +	ret = scnprintf(kbuf, count, "SLAB_PAGE slab_name:%s\n", kmem_cache->name);
> +
> +	return ret;
> +}
> +#endif

Or we could do this typesafely ...

	struct slab *slab = folio_slab(folio);
	struct kmem_cache *kmem_cache = slab->slab_cache;

... and then there's no need to pass in a 'data' to the function.