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
Date: Wed, 11 Jan 2006 14:42:55 -0800 [thread overview]
Message-ID: <20060111224255.GD9091@holomorphy.com> (raw)
In-Reply-To: <1137016960.9672.5.camel@localhost.localdomain>
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
WARNING: multiple messages have this Message-ID (diff)
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
Date: Wed, 11 Jan 2006 14:42:55 -0800 [thread overview]
Message-ID: <20060111224255.GD9091@holomorphy.com> (raw)
In-Reply-To: <1137016960.9672.5.camel@localhost.localdomain>
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
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2006-01-11 22:43 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-01-10 19:22 Hugetlb: Shared memory race Adam Litke
2006-01-10 19:22 ` Adam Litke
2006-01-10 19:44 ` William Lee Irwin III
2006-01-10 19:44 ` William Lee Irwin III
2006-01-11 22:02 ` [PATCH 1/2] hugetlb: Delay page zeroing for faulted pages Adam Litke
2006-01-11 22:02 ` Adam Litke
2006-01-11 22:24 ` [PATCH 2/2] hugetlb: synchronize alloc with page cache insert Adam Litke
2006-01-11 22:24 ` Adam Litke
2006-01-11 22:52 ` William Lee Irwin III
2006-01-11 22:52 ` William Lee Irwin III
2006-01-11 23:03 ` Adam Litke
2006-01-11 23:03 ` Adam Litke
2006-01-11 23:24 ` William Lee Irwin III
2006-01-11 23:24 ` William Lee Irwin III
2006-01-11 23:46 ` Chen, Kenneth W
2006-01-11 23:46 ` Chen, Kenneth W
2006-01-12 0:40 ` Chen, Kenneth W
2006-01-12 0:40 ` Chen, Kenneth W
2006-01-12 1:05 ` William Lee Irwin III
2006-01-12 1:05 ` William Lee Irwin III
2006-01-12 17:26 ` Adam Litke
2006-01-12 17:26 ` Adam Litke
2006-01-12 19:07 ` Chen, Kenneth W
2006-01-12 19:07 ` Chen, Kenneth W
2006-01-12 19:48 ` Adam Litke
2006-01-12 19:48 ` Adam Litke
2006-01-12 20:06 ` Chen, Kenneth W
2006-01-12 20:06 ` Chen, Kenneth W
2006-01-11 22:42 ` William Lee Irwin III [this message]
2006-01-11 22:42 ` [PATCH 1/2] hugetlb: Delay page zeroing for faulted pages William Lee Irwin III
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20060111224255.GD9091@holomorphy.com \
--to=wli@holomorphy.com \
--cc=agl@us.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.