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Message-ID: <4128bc10-5110-983c-192f-afe8b856b329@huawei.com>
Date:   Mon, 3 Jul 2023 17:29:54 +0800
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Subject: Re: [PATCH 4/4] mm/memory: convert do_read_fault() to use folios
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To:     Sidhartha Kumar <sidhartha.kumar@oracle.com>,
        <linux-kernel@vger.kernel.org>, <linux-mm@kvack.org>
CC:     <akpm@linux-foundation.org>, <willy@infradead.org>
References: <20230703055850.227169-1-sidhartha.kumar@oracle.com>
 <20230703055850.227169-4-sidhartha.kumar@oracle.com>
From:   "zhangpeng (AS)" <zhangpeng362@huawei.com>
In-Reply-To: <20230703055850.227169-4-sidhartha.kumar@oracle.com>
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On 2023/7/3 13:58, Sidhartha Kumar wrote:

> Saves one implicit call to compound_head()
>
> Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>

Reviewed-by: ZhangPeng <zhangpeng362@huawei.com>

> ---
>   mm/memory.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/mm/memory.c b/mm/memory.c
> index 33bf13431974c..b97c66df4adac 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -4528,6 +4528,7 @@ static inline bool should_fault_around(struct vm_fault *vmf)
>   static vm_fault_t do_read_fault(struct vm_fault *vmf)
>   {
>   	vm_fault_t ret = 0;
> +	struct folio *folio = page_folio(vmf->page);
>   
>   	/*
>   	 * Let's call ->map_pages() first and use ->fault() as fallback
> @@ -4545,9 +4546,9 @@ static vm_fault_t do_read_fault(struct vm_fault *vmf)
>   		return ret;
>   
>   	ret |= finish_fault(vmf);
> -	unlock_page(vmf->page);
> +	folio_unlock(folio);
>   	if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))
> -		put_page(vmf->page);
> +		folio_put(folio);
>   	return ret;
>   }
>