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Subject: Re: [PATCH] hugepage: support ZERO_PAGE()
From: Adam Litke <agl@us.ibm.com>
To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hugh@veritas.com>,
       Kawai Hidehiro <hidehiro.kawai.ez@hitachi.com>,
       William Irwin <wli@holomorphy.com>, LKML <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@linux-foundation.org>, Mel Gorman <mel@csn.ul.ie>
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Organization: IBM
Date: Tue, 02 Sep 2008 12:27:48 -0500
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On Tue, 2008-09-02 at 10:21 +0900, KOSAKI Motohiro wrote:
> +static int huge_zeropage_ok(pte_t *ptep, int write, int shared)
> +{
> +	if (!ptep)
> +		return 0;
> +
> +	if (write)
> +		return 0;
> +
> +	if (shared)
> +		return 0;
> +
> +	return huge_pte_none(huge_ptep_get(ptep));
> +}

In addition to the comments from Mel, I'd like to see this function
collapsed a bit...

if (!ptep || write || shared)
	return 0;
else
	return huge_pte_none(huge_ptep_get(ptep));

-- 
Adam Litke - (agl at us.ibm.com)
IBM Linux Technology Center