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Date:   Sun, 24 May 2020 20:49:22 +0300
From:   Mike Rapoport <rppt@linux.ibm.com>
To:     daeroro <skseofh@gmail.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/memblock:Do not retry a range that has already been
 checked
Message-ID: <20200524174922.GB1515425@linux.ibm.com>
References: <20200524141640.GA10017@roro-Lenovo-Y520-15IKBN>
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On Sun, May 24, 2020 at 11:16:40PM +0900, daeroro wrote:
> The range that has already been checked
> don't have to be checked in a second attempt.

The first attempts tries to find free memory in the interval [min_addr,
max_addr) and the second attempt does not care about min_addr and looks
for free memory in the interval [0, max_addr).

Is there a problem you see with this algorthim?

> Signed-off-by: daeroro <skseofh@naver.com>
> ---
>  mm/memblock.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/memblock.c b/mm/memblock.c
> index 39aceafc57f6..6f72fae415ee 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1489,7 +1489,7 @@ static void * __init memblock_alloc_internal(
>  
>  	/* retry allocation without lower limit */
>  	if (!alloc && min_addr)
> -		alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid,
> +		alloc = memblock_alloc_range_nid(size, align, 0, min_addr, nid,
>  						exact_nid);
>  
>  	if (!alloc)
> -- 
> 2.17.1
> 

-- 
Sincerely yours,
Mike.