From: Rik van Riel <riel@redhat.com>
To: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>, Michal Hocko <mhocko@suse.cz>,
Linux-MM <linux-mm@kvack.org>,
David Gibson <david@gibson.dropbear.id.au>,
Ken Chen <kenchen@google.com>,
Cong Wang <xiyou.wangcong@gmail.com>,
LKML <linux-kernel@vger.kernel.org>,
Larry Woodman <lwoodman@redhat.com>
Subject: Re: [PATCH -alternative] mm: hugetlbfs: Close race during teardown of hugetlbfs shared page tables V2 (resend)
Date: Thu, 26 Jul 2012 13:42:26 -0400 [thread overview]
Message-ID: <50118182.8030308@redhat.com> (raw)
In-Reply-To: <alpine.LSU.2.00.1207222033030.6810@eggly.anvils>
On 07/23/2012 12:04 AM, Hugh Dickins wrote:
> Please don't be upset if I say that I don't like either of your patches.
> Mainly for obvious reasons - I don't like Mel's because anything with
> trylock retries and nested spinlocks worries me before I can even start
> to think about it; and I don't like Michal's for the same reason as Mel,
> that it spreads more change around in common paths than we would like.
I have a naive question.
In huge_pmd_share, we protect ourselves by taking
the mapping->i_mmap_mutex.
Is there any reason we could not take the i_mmap_mutex
in the huge_pmd_unshare path?
I see that hugetlb_change_protection already takes that
lock. Is there something preventing __unmap_hugepage_range
from also taking mapping->i_mmap_mutex?
That way the sharing and the unsharing code are
protected by the same, per shm segment, lock.
--
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>
WARNING: multiple messages have this Message-ID (diff)
From: Rik van Riel <riel@redhat.com>
To: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>, Michal Hocko <mhocko@suse.cz>,
Linux-MM <linux-mm@kvack.org>,
David Gibson <david@gibson.dropbear.id.au>,
Ken Chen <kenchen@google.com>,
Cong Wang <xiyou.wangcong@gmail.com>,
LKML <linux-kernel@vger.kernel.org>,
Larry Woodman <lwoodman@redhat.com>
Subject: Re: [PATCH -alternative] mm: hugetlbfs: Close race during teardown of hugetlbfs shared page tables V2 (resend)
Date: Thu, 26 Jul 2012 13:42:26 -0400 [thread overview]
Message-ID: <50118182.8030308@redhat.com> (raw)
In-Reply-To: <alpine.LSU.2.00.1207222033030.6810@eggly.anvils>
On 07/23/2012 12:04 AM, Hugh Dickins wrote:
> Please don't be upset if I say that I don't like either of your patches.
> Mainly for obvious reasons - I don't like Mel's because anything with
> trylock retries and nested spinlocks worries me before I can even start
> to think about it; and I don't like Michal's for the same reason as Mel,
> that it spreads more change around in common paths than we would like.
I have a naive question.
In huge_pmd_share, we protect ourselves by taking
the mapping->i_mmap_mutex.
Is there any reason we could not take the i_mmap_mutex
in the huge_pmd_unshare path?
I see that hugetlb_change_protection already takes that
lock. Is there something preventing __unmap_hugepage_range
from also taking mapping->i_mmap_mutex?
That way the sharing and the unsharing code are
protected by the same, per shm segment, lock.
next prev parent reply other threads:[~2012-07-26 18:21 UTC|newest]
Thread overview: 100+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-20 13:49 [PATCH] mm: hugetlbfs: Close race during teardown of hugetlbfs shared page tables v2 Mel Gorman
2012-07-20 13:49 ` Mel Gorman
2012-07-20 14:11 ` [PATCH] mm: hugetlbfs: Close race during teardown of hugetlbfs shared page tables V2 (resend) Mel Gorman
2012-07-20 14:11 ` Mel Gorman
2012-07-20 14:29 ` Michal Hocko
2012-07-20 14:29 ` Michal Hocko
2012-07-20 14:37 ` Mel Gorman
2012-07-20 14:37 ` Mel Gorman
2012-07-20 14:40 ` Michal Hocko
2012-07-20 14:40 ` Michal Hocko
2012-07-20 14:36 ` [PATCH -alternative] " Michal Hocko
2012-07-20 14:36 ` Michal Hocko
2012-07-20 14:51 ` Mel Gorman
2012-07-20 14:51 ` Mel Gorman
2012-07-23 4:04 ` Hugh Dickins
2012-07-23 4:04 ` Hugh Dickins
2012-07-23 11:40 ` Mel Gorman
2012-07-23 11:40 ` Mel Gorman
2012-07-24 1:08 ` Hugh Dickins
2012-07-24 1:08 ` Hugh Dickins
2012-07-24 8:32 ` Michal Hocko
2012-07-24 8:32 ` Michal Hocko
2012-07-24 9:34 ` Mel Gorman
2012-07-24 9:34 ` Mel Gorman
2012-07-24 10:04 ` Michal Hocko
2012-07-24 10:04 ` Michal Hocko
2012-07-24 19:23 ` Hugh Dickins
2012-07-24 19:23 ` Hugh Dickins
2012-07-25 8:36 ` Mel Gorman
2012-07-25 8:36 ` Mel Gorman
2012-07-26 17:42 ` Rik van Riel [this message]
2012-07-26 17:42 ` Rik van Riel
2012-07-26 18:04 ` Larry Woodman
2012-07-26 18:04 ` Larry Woodman
2012-07-27 8:42 ` Mel Gorman
2012-07-27 8:42 ` Mel Gorman
2012-07-26 18:37 ` Rik van Riel
2012-07-26 18:37 ` Rik van Riel
2012-07-26 21:03 ` Larry Woodman
2012-07-26 21:03 ` Larry Woodman
2012-07-27 3:48 ` Larry Woodman
2012-07-27 3:48 ` Larry Woodman
2012-07-27 10:10 ` Larry Woodman
2012-07-27 10:10 ` Larry Woodman
2012-07-27 10:23 ` Mel Gorman
2012-07-27 10:23 ` Mel Gorman
2012-07-27 10:36 ` Larry Woodman
2012-07-27 10:36 ` Larry Woodman
2012-07-30 19:11 ` Larry Woodman
2012-07-30 19:11 ` Larry Woodman
2012-07-31 12:16 ` Hillf Danton
2012-07-31 12:16 ` Hillf Danton
2012-07-31 12:46 ` Mel Gorman
2012-07-31 12:46 ` Mel Gorman
2012-07-31 13:07 ` Larry Woodman
2012-07-31 13:07 ` Larry Woodman
2012-07-31 13:29 ` Mel Gorman
2012-07-31 13:29 ` Mel Gorman
2012-07-31 13:21 ` Michal Hocko
2012-07-31 13:21 ` Michal Hocko
2012-07-31 17:49 ` Larry Woodman
2012-07-31 17:49 ` Larry Woodman
2012-07-31 20:06 ` Michal Hocko
2012-07-31 20:06 ` Michal Hocko
2012-07-31 20:57 ` Larry Woodman
2012-07-31 20:57 ` Larry Woodman
2012-08-01 2:45 ` Larry Woodman
2012-08-01 2:45 ` Larry Woodman
2012-08-01 8:20 ` Michal Hocko
2012-08-01 8:20 ` Michal Hocko
2012-08-01 12:32 ` Michal Hocko
2012-08-01 12:32 ` Michal Hocko
2012-08-01 15:06 ` Larry Woodman
2012-08-01 15:06 ` Larry Woodman
2012-08-02 7:19 ` Michal Hocko
2012-08-02 7:19 ` Michal Hocko
2012-08-02 7:37 ` Mel Gorman
2012-08-02 7:37 ` Mel Gorman
2012-08-02 12:36 ` Michal Hocko
2012-08-02 12:36 ` Michal Hocko
2012-08-02 13:33 ` Mel Gorman
2012-08-02 13:33 ` Mel Gorman
2012-08-02 13:53 ` Michal Hocko
2012-08-02 13:53 ` Michal Hocko
2012-07-31 18:03 ` Rik van Riel
2012-07-31 18:03 ` Rik van Riel
2012-07-26 18:31 ` Rik van Riel
2012-07-26 18:31 ` Rik van Riel
2012-07-27 9:02 ` Michal Hocko
2012-07-27 9:02 ` Michal Hocko
2012-07-26 16:01 ` [PATCH] mm: hugetlbfs: Close race during teardown of hugetlbfs shared page tables v2 Larry Woodman
2012-07-26 16:01 ` Larry Woodman
2012-07-27 8:47 ` Mel Gorman
2012-07-27 8:47 ` Mel Gorman
2012-07-26 21:00 ` Rik van Riel
2012-07-26 21:00 ` Rik van Riel
2012-07-26 21:54 ` Hugh Dickins
2012-07-26 21:54 ` Hugh Dickins
2012-07-27 8:52 ` Mel Gorman
2012-07-27 8:52 ` Mel Gorman
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=50118182.8030308@redhat.com \
--to=riel@redhat.com \
--cc=david@gibson.dropbear.id.au \
--cc=hughd@google.com \
--cc=kenchen@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=lwoodman@redhat.com \
--cc=mgorman@suse.de \
--cc=mhocko@suse.cz \
--cc=xiyou.wangcong@gmail.com \
/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.