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Date:   Fri, 7 Aug 2020 20:47:01 +0800
From:   Baoquan He <bhe@redhat.com>
To:     Wei Yang <richard.weiyang@linux.alibaba.com>
Cc:     mike.kravetz@oracle.com, akpm@linux-foundation.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 01/10] mm/hugetlb: not necessary to coalesce regions
 recursively
Message-ID: <20200807124701.GL14854@MiWiFi-R3L-srv>
References: <20200807091251.12129-1-richard.weiyang@linux.alibaba.com>
 <20200807091251.12129-2-richard.weiyang@linux.alibaba.com>
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On 08/07/20 at 05:12pm, Wei Yang wrote:
> Per my understanding, we keep the regions ordered and would always
> coalesce regions properly. So the task to keep this property is just
> to coalesce its neighbour.
> 
> Let's simplify this.
> 
> Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
> ---
>  mm/hugetlb.c | 6 +-----
>  1 file changed, 1 insertion(+), 5 deletions(-)
> 
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 590111ea6975..62ec74f6d03f 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -307,8 +307,7 @@ static void coalesce_file_region(struct resv_map *resv, struct file_region *rg)
>  		list_del(&rg->link);
>  		kfree(rg);
>  
> -		coalesce_file_region(resv, prg);
> -		return;
> +		rg = prg;
>  	}
>  
>  	nrg = list_next_entry(rg, link);
> @@ -318,9 +317,6 @@ static void coalesce_file_region(struct resv_map *resv, struct file_region *rg)
>  
>  		list_del(&rg->link);
>  		kfree(rg);
> -
> -		coalesce_file_region(resv, nrg);

I agree with the change. But this change the original behaviour of
coalesce_file_region, not sure if there's any reason we need to do that,
maybe Mike can give a judgement. Personally,

Reviewed-by: Baoquan He <bhe@redhat.com>

> -		return;
>  	}
>  }
>  
> -- 
> 2.20.1 (Apple Git-117)
> 
>