From: Andi Kleen <andi@firstfloor.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>,
LKML <linux-kernel@vger.kernel.org>,
Andi Kleen <andi@firstfloor.org>,
Alan Cox <alan@lxorguk.ukuu.org.uk>,
Al Viro <viro@ZenIV.linux.org.uk>,
bfields@fieldses.org, xfs-masters@oss.sgi.com
Subject: Re: RFC: Fix f_flags races without the BKL
Date: Mon, 29 Dec 2008 16:27:32 +0100 [thread overview]
Message-ID: <20081229152732.GH496@one.firstfloor.org> (raw)
In-Reply-To: <20081229124151.GA29634@redhat.com>
On Mon, Dec 29, 2008 at 01:41:51PM +0100, Oleg Nesterov wrote:
> On 12/29, Jonathan Corbet wrote:
> >
> > After pondering for a while, I couldn't come up with anything better than a
> > global file->f_flags mutex. There's no point in bloating struct file with
> > a mutex just for this purpose; it's hard to imagine that there will be any
> > real contention for this lock.
>
> Yes, this patch is simple and straightforward, but now we can't change
> ->f_flags in non-preempible context. And the global lock is not very
> nice anyway.
>
> Once again, can't we use O_LOCK_FLAGS bit? I agree, it is a bit ugly,
> and I won't insist if you don't like is.
I would prefer O_LOCK_FLAGS bit too. The global lock is not very nice
and I don't doubt someone will come up with a workload which
pounds on it.
-Andi
--
ak@linux.intel.com
next prev parent reply other threads:[~2008-12-29 15:14 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-12-29 11:13 RFC: Fix f_flags races without the BKL Jonathan Corbet
2008-12-29 11:57 ` Sam Ravnborg
2008-12-30 12:49 ` Jonathan Corbet
2008-12-29 12:41 ` Oleg Nesterov
2008-12-29 15:27 ` Andi Kleen [this message]
2008-12-30 12:59 ` Jonathan Corbet
2008-12-30 13:04 ` [xfs-masters] " Christoph Hellwig
2008-12-30 13:37 ` Andi Kleen
2008-12-30 14:48 ` Christoph Hellwig
2008-12-31 9:52 ` Jonathan Corbet
2008-12-30 14:55 ` Andi Kleen
2009-01-08 23:28 ` Jonathan Corbet
2009-01-09 10:08 ` Oleg Nesterov
2009-01-09 13:18 ` Jonathan Corbet
2009-01-09 14:03 ` Oleg Nesterov
2009-01-09 15:09 ` Andi Kleen
2008-12-29 12:50 ` [xfs-masters] " Christoph Hellwig
2008-12-29 15:15 ` Andi Kleen
2009-01-02 18:29 ` Al Viro
2009-01-02 18:27 ` Al Viro
2009-01-02 18:42 ` Al Viro
2009-01-02 19:09 ` Oleg Nesterov
2009-01-02 19:54 ` Al Viro
2009-01-03 16:45 ` Oleg Nesterov
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