Date: Wed, 11 Jan 2006 14:42:55 -0800
From: William Lee Irwin III <wli@holomorphy.com>
To: Adam Litke <agl@us.ibm.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH 1/2] hugetlb: Delay page zeroing for faulted pages
Message-ID: <20060111224255.GD9091@holomorphy.com>
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On Wed, Jan 11, 2006 at 04:02:40PM -0600, Adam Litke wrote:
> I've come up with a much better idea to resolve the issue I mention
> below.  The attached patch changes hugetlb_no_page to allocate unzeroed
> huge pages initially.  For shared mappings, we wait until after
> inserting the page into the page_cache succeeds before we zero it.  This
> has a side benefit of preventing the wasted zeroing that happened often
> in the original code.  The page_lock should guard against someone else
> using the page before it has been zeroed (but correct me if I am wrong
> here).  The patch doesn't completely close the race (there is a much
> smaller window without the zeroing though).  The next patch should close
> the race window completely.

Looks better to me.

Signed-off-by: William Irwin <wli@holomorphy.com>


-- wli
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