From: Rik van Riel <riel@redhat.com>
To: Mel Gorman <mel@csn.ul.ie>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Andrea Arcangeli <aarcange@redhat.com>,
Minchan Kim <minchan.kim@gmail.com>,
Linux-MM <linux-mm@kvack.org>,
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
LKML <linux-kernel@vger.kernel.org>,
Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 3/5] track the root (oldest) anon_vma
Date: Wed, 12 May 2010 17:01:38 -0400 [thread overview]
Message-ID: <4BEB1732.1010503@redhat.com> (raw)
In-Reply-To: <20100512205941.GO24989@csn.ul.ie>
On 05/12/2010 04:59 PM, Mel Gorman wrote:
> On Wed, May 12, 2010 at 01:39:58PM -0400, Rik van Riel wrote:
>> Subject: track the root (oldest) anon_vma
>>
>> Track the root (oldest) anon_vma in each anon_vma tree. Because we only
>> take the lock on the root anon_vma, we cannot use the lock on higher-up
>> anon_vmas to lock anything. This makes it impossible to do an indirect
>> lookup of the root anon_vma, since the data structures could go away from
>> under us.
>>
>> However, a direct pointer is safe because the root anon_vma is always the
>> last one that gets freed on munmap or exit, by virtue of the same_vma list
>> order and unlink_anon_vmas walking the list forward.
>>
>
> Shouldn't this be "usually the last one that gets freed" because of the
> ref-counting by KSM aspect? Minor nit anyway.
It needs to be the last one that gets freed. Patch 5/5 makes
sure that it is when KSM refcounting is involved.
>> Signed-off-by: Rik van Riel<riel@redhat.com>
>
> Otherwise
>
> Acked-by: Mel Gorman<mel@csn.ul.ie>
Thank you for reviewing these patches.
--
All rights reversed
WARNING: multiple messages have this Message-ID (diff)
From: Rik van Riel <riel@redhat.com>
To: Mel Gorman <mel@csn.ul.ie>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Andrea Arcangeli <aarcange@redhat.com>,
Minchan Kim <minchan.kim@gmail.com>,
Linux-MM <linux-mm@kvack.org>,
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
LKML <linux-kernel@vger.kernel.org>,
Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 3/5] track the root (oldest) anon_vma
Date: Wed, 12 May 2010 17:01:38 -0400 [thread overview]
Message-ID: <4BEB1732.1010503@redhat.com> (raw)
In-Reply-To: <20100512205941.GO24989@csn.ul.ie>
On 05/12/2010 04:59 PM, Mel Gorman wrote:
> On Wed, May 12, 2010 at 01:39:58PM -0400, Rik van Riel wrote:
>> Subject: track the root (oldest) anon_vma
>>
>> Track the root (oldest) anon_vma in each anon_vma tree. Because we only
>> take the lock on the root anon_vma, we cannot use the lock on higher-up
>> anon_vmas to lock anything. This makes it impossible to do an indirect
>> lookup of the root anon_vma, since the data structures could go away from
>> under us.
>>
>> However, a direct pointer is safe because the root anon_vma is always the
>> last one that gets freed on munmap or exit, by virtue of the same_vma list
>> order and unlink_anon_vmas walking the list forward.
>>
>
> Shouldn't this be "usually the last one that gets freed" because of the
> ref-counting by KSM aspect? Minor nit anyway.
It needs to be the last one that gets freed. Patch 5/5 makes
sure that it is when KSM refcounting is involved.
>> Signed-off-by: Rik van Riel<riel@redhat.com>
>
> Otherwise
>
> Acked-by: Mel Gorman<mel@csn.ul.ie>
Thank you for reviewing these patches.
--
All rights reversed
--
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:[~2010-05-12 21:02 UTC|newest]
Thread overview: 102+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-05-12 17:38 [PATCH 0/5] always lock the root anon_vma Rik van Riel
2010-05-12 17:38 ` Rik van Riel
2010-05-12 17:39 ` [PATCH 1/5] rename anon_vma_lock to vma_lock_anon_vma Rik van Riel
2010-05-12 17:39 ` Rik van Riel
2010-05-12 20:57 ` Mel Gorman
2010-05-12 20:57 ` Mel Gorman
2010-05-13 0:30 ` KAMEZAWA Hiroyuki
2010-05-13 0:30 ` KAMEZAWA Hiroyuki
2010-05-12 17:39 ` [PATCH 3/5] track the root (oldest) anon_vma Rik van Riel
2010-05-12 17:39 ` Rik van Riel
2010-05-12 20:59 ` Mel Gorman
2010-05-12 20:59 ` Mel Gorman
2010-05-12 21:01 ` Rik van Riel [this message]
2010-05-12 21:01 ` Rik van Riel
2010-05-13 0:38 ` KAMEZAWA Hiroyuki
2010-05-13 0:38 ` KAMEZAWA Hiroyuki
2010-05-13 2:25 ` Rik van Riel
2010-05-13 2:25 ` Rik van Riel
2010-05-14 0:04 ` KAMEZAWA Hiroyuki
2010-05-14 0:04 ` KAMEZAWA Hiroyuki
2010-05-12 17:40 ` [PATCH 4/5] always lock " Rik van Riel
2010-05-12 17:40 ` Rik van Riel
2010-05-12 21:02 ` Mel Gorman
2010-05-12 21:02 ` Mel Gorman
2010-05-12 21:08 ` Rik van Riel
2010-05-12 21:08 ` Rik van Riel
2010-05-13 9:54 ` Mel Gorman
2010-05-13 9:54 ` Mel Gorman
2010-05-13 14:33 ` [PATCH -v2 " Rik van Riel
2010-05-13 14:33 ` Rik van Riel
2010-05-13 21:09 ` Andrew Morton
2010-05-13 21:09 ` Andrew Morton
2010-05-13 22:50 ` Rik van Riel
2010-05-13 22:50 ` Rik van Riel
2010-05-14 9:33 ` Mel Gorman
2010-05-14 9:33 ` Mel Gorman
2010-05-26 4:00 ` Rik van Riel
2010-05-26 4:00 ` Rik van Riel
2010-05-26 4:15 ` Andrew Morton
2010-05-26 4:15 ` Andrew Morton
2010-05-26 5:46 ` james toy
2010-05-26 5:46 ` james toy
2010-06-01 0:57 ` james toy
2010-06-01 0:57 ` james toy
2010-05-26 15:24 ` [PATCH -v2 0/5] always lock the root anon_vma Rik van Riel
2010-05-26 15:24 ` Rik van Riel
2010-05-26 15:25 ` [PATCH 1/5] rename anon_vma_lock to vma_lock_anon_vma Rik van Riel
2010-05-26 15:25 ` Rik van Riel
2010-05-26 17:25 ` Linus Torvalds
2010-05-26 17:25 ` Linus Torvalds
2010-05-26 19:01 ` Rik van Riel
2010-05-26 19:01 ` Rik van Riel
2010-05-26 19:25 ` Linus Torvalds
2010-05-26 19:25 ` Linus Torvalds
2010-05-26 19:35 ` Rik van Riel
2010-05-26 19:35 ` Rik van Riel
2010-05-26 15:25 ` [PATCH 2/5] change direct call of spin_lock(anon_vma->lock) to inline function Rik van Riel
2010-05-26 15:25 ` Rik van Riel
2010-05-26 15:26 ` [PATCH 3/5] track the root (oldest) anon_vma Rik van Riel
2010-05-26 15:26 ` Rik van Riel
2010-05-26 15:27 ` [PATCH 4/5] always lock " Rik van Riel
2010-05-26 15:27 ` Rik van Riel
2010-05-26 15:27 ` [PATCH 5/5] extend KSM refcounts to the anon_vma root Rik van Riel
2010-05-26 15:27 ` Rik van Riel
2010-05-12 21:55 ` [PATCH 4/5] always lock the root (oldest) anon_vma Linus Torvalds
2010-05-12 21:55 ` Linus Torvalds
2010-05-12 22:18 ` Rik van Riel
2010-05-12 22:18 ` Rik van Riel
2010-05-12 22:26 ` Linus Torvalds
2010-05-12 22:26 ` Linus Torvalds
2010-05-12 17:41 ` [PATCH 5/5] extend KSM refcounts to the anon_vma root Rik van Riel
2010-05-12 17:41 ` Rik van Riel
2010-05-12 21:07 ` Mel Gorman
2010-05-12 21:07 ` Mel Gorman
2010-05-12 21:09 ` Rik van Riel
2010-05-12 21:09 ` Rik van Riel
2010-05-13 11:26 ` Mel Gorman
2010-05-13 11:26 ` Mel Gorman
2010-05-13 13:11 ` Rik van Riel
2010-05-13 13:11 ` Rik van Riel
2010-05-13 13:24 ` Mel Gorman
2010-05-13 13:24 ` Mel Gorman
2010-05-13 14:34 ` [PATCH -v2 " Rik van Riel
2010-05-13 14:34 ` Rik van Riel
2010-05-19 1:05 ` Andrea Arcangeli
2010-05-19 1:05 ` Andrea Arcangeli
2010-05-12 17:41 ` [PATCH 2/5] change direct call of spin_lock(anon_vma->lock) to inline function Rik van Riel
2010-05-12 17:41 ` Rik van Riel
2010-05-12 20:58 ` Mel Gorman
2010-05-12 20:58 ` Mel Gorman
2010-05-13 0:32 ` KAMEZAWA Hiroyuki
2010-05-13 0:32 ` KAMEZAWA Hiroyuki
2010-05-20 22:42 ` [PATCH 6/5] adjust mm_take_all_locks to anon-vma-root locking Andrea Arcangeli
2010-05-20 22:42 ` Andrea Arcangeli
2010-05-20 23:07 ` Rik van Riel
2010-05-20 23:07 ` Rik van Riel
-- strict thread matches above, loose matches on Subject: below --
2010-05-26 19:38 [PATCH -v3 0/5] always lock the root anon_vma Rik van Riel
2010-05-26 19:40 ` [PATCH 3/5] track the root (oldest) anon_vma Rik van Riel
2010-05-26 19:40 ` Rik van Riel
2010-05-26 20:34 ` Larry Woodman
2010-05-26 20:34 ` Larry Woodman
2010-05-27 13:48 ` Minchan Kim
2010-05-27 13:48 ` Minchan Kim
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=4BEB1732.1010503@redhat.com \
--to=riel@redhat.com \
--cc=aarcange@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=kamezawa.hiroyu@jp.fujitsu.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mel@csn.ul.ie \
--cc=minchan.kim@gmail.com \
--cc=torvalds@linux-foundation.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.